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Gafane-Matemane LF, Craig A, Kruger R, Alaofin OS, Ware LJ, Jones ESW, Kengne AP. Hypertension in sub-Saharan Africa: the current profile, recent advances, gaps, and priorities. J Hum Hypertens 2024:10.1038/s41371-024-00913-6. [PMID: 38698111 DOI: 10.1038/s41371-024-00913-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 04/15/2024] [Accepted: 04/17/2024] [Indexed: 05/05/2024]
Abstract
Recent global and regional reports consistently confirm the high and increasing prevalence of hypertension in sub-Saharan Africa (SSA), with poor detection, treatment, and control rates. This narrative review summarises the burden of hypertension in SSA and recent findings from community-based hypertension management strategies. We further outline prominent risk factors according to recent data and associated underlying mechanisms for hypertension development. An extensive review of literature showed that most countries have reported on the prevalence of hypertension during 2017-2023, despite limitations linked to the lack of nationally representative studies, heterogeneity of sampling and data collection methods. Task-shifting approaches that assign roles to model patients and community health workers reported improved linkage to healthcare services and adherence to medication, with inconsistent findings on blood pressure (BP)-lowering effects over time. The regularly reported risk factors include unhealthy diet, sedentary lifestyle, increased adiposity and underweight, ageing, level of education, and/or income as well as psychosocial factors. Newer data on the pathophysiological mechanisms leading to hypertension and potential areas of intervention are reported from children and adults and include, among others, salt-handling and volume overload, endothelial function, BP dipping patterns and the role of human immunodeficiency virus . To conclude, significant strides have been made in data reporting from SSA on the burden of hypertension in the region as well as biomarker research to improve understanding and identification of areas of intervention. However, gaps remain on linkage between knowledge generation, translation, and implementation research. Coordinated studies addressing both discovery science and public health are crucial to curb hypertension development and improve management in SSA.
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Affiliation(s)
- Lebo F Gafane-Matemane
- Hypertension in Africa Research Team, North-West University, Potchefstroom, 2520, South Africa.
- SAMRC Research Unit for Hypertension and Cardiovascular Disease, North-West University, Potchefstroom, 2520, South Africa.
| | - Ashleigh Craig
- SAMRC/Wits Developmental Pathways for Health Research Unit (DPHRU), University of the Witwatersrand, Soweto, 1864, South Africa
| | - Ruan Kruger
- Hypertension in Africa Research Team, North-West University, Potchefstroom, 2520, South Africa
- SAMRC Research Unit for Hypertension and Cardiovascular Disease, North-West University, Potchefstroom, 2520, South Africa
| | - Omotayo S Alaofin
- Hypertension in Africa Research Team, North-West University, Potchefstroom, 2520, South Africa
| | - Lisa J Ware
- SAMRC/Wits Developmental Pathways for Health Research Unit (DPHRU), University of the Witwatersrand, Soweto, 1864, South Africa
| | - Erika S W Jones
- Division of Nephrology and Hypertension, Groote Schuur Hospital and Kidney and Hypertension Research Unit, University of Cape Town, Cape Town, South Africa
| | - Andre Pascal Kengne
- Non-Communicable Diseases Research Unit, South African Medical Research Council, Francie Van Zijl Dr, Parow Valley, Cape Town, 7501, South Africa
- Department of Biological and Environmental Sciences, Faculty of Natural Sciences, Walter Sisulu University, Mthatha, South Africa
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Nsanya MK, Abramson R, Kisigo GA, Hickner A, Nyanza EC, Peck RN, Kapiga SH. Hypertension among adolescents in sub-Saharan Africa: a systematic review. Front Cardiovasc Med 2023; 10:1251817. [PMID: 38155990 PMCID: PMC10754047 DOI: 10.3389/fcvm.2023.1251817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Accepted: 10/18/2023] [Indexed: 12/30/2023] Open
Abstract
Introduction Hypertension (HTN) among adolescents is common in high-income countries, and leads to increased premature cardiovascular diseases (CVD). In sub-Saharan Africa (SSA), the prevalence of HTN among adolescents, associated risk factors and CVD complications are not well-described. Such data is needed for planning public health programs to prevent premature CVD in SSA. Methods We systematically searched 5 databases (MEDLINE, Embase, Google Scholar, Web of Science, and African Index Medicus) from their establishment to December 2021. Key search terms were: adolescent, arterial hypertension, and names of the 48 countries in SSA. We used Covidence® to manage the search results. The review was registered in the Open Science Framework (OSF) https://osf.io/p5sbt/. Results We identified 4,008 articles out of which we screened 3,088 abstracts, and reviewed 583 full-text articles. We finally included 92 articles that were published between 1968 to December 2021. The majority were cross-sectional studies (80%) and conducted in school settings (78%). The risk of bias was low for 59 studies (64.1%), moderate for 29 studies (31.5%), and high for 4 studies (4.3%). Overall, the prevalence of HTN varied widely from 0.18% to 34.0% with a median (IQR) of 5.5% (3.1%, 11.1%). It was relatively higher in studies using automated blood pressure (BP) devices, and in studies defining HTN using thresholds based on percentile BP distribution for one's height, age, and sex. In addition, the prevalence of HTN was significantly higher in studies from Southern Africa region of SSA and positively correlated with the year of publication. Across studies, traditional risk factors such as age, sex, body mass index, and physical inactivity, were commonly found to be associated with HTN. In contrast, non-traditional risk factors related to poverty and tropical diseases were rarely assessed. Only three studies investigated the CVD complications related to HTN in the study population. Conclusion The prevalence of HTN among adolescents in SSA is high indicating that this is a major health problem. Data on non-traditional risk factors and complications are scarce. Longitudinal studies are needed to clearly define the rates, causes, and complications of HTN. Systematic Review Registration https://osf.io/p5sbt/, identifier (10.17605/OSF.IO/P5SBT).
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Affiliation(s)
- Mussa K Nsanya
- Mwanza Intervention Trials Unit/National Institute for Medical Research, Mwanza, Tanzania
| | - Rachel Abramson
- Weill Cornell Medicine - Cornell University, New York, NY, United States
| | - Godfrey A Kisigo
- Mwanza Intervention Trials Unit/National Institute for Medical Research, Mwanza, Tanzania
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Andy Hickner
- Weill Cornell Medicine - Cornell University, New York, NY, United States
| | - Elias C Nyanza
- Catholic University of Health and Allied Sciences, School of Public Health, Mwanza, Tanzania
| | - Robert N Peck
- Mwanza Intervention Trials Unit/National Institute for Medical Research, Mwanza, Tanzania
- Weill Cornell Medicine - Cornell University, New York, NY, United States
- Catholic University of Health and Allied Sciences, School of Public Health, Mwanza, Tanzania
| | - Saidi H Kapiga
- Mwanza Intervention Trials Unit/National Institute for Medical Research, Mwanza, Tanzania
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
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Craig A, Breet Y, Gafane-Matemane LF, Norris SA, Kruger R. Detecting and Managing Childhood Onset Hypertension in Africa: A Call to Action. Curr Hypertens Rep 2023; 25:211-230. [PMID: 37318686 PMCID: PMC10491553 DOI: 10.1007/s11906-023-01247-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/22/2023] [Indexed: 06/16/2023]
Abstract
PURPOSE OF REVIEW To review recent evidence on childhood hypertension across Africa, identifying knowledge gaps, challenges and priorities, and highlight clinical perspectives in managing primary hypertension. RECENT FINDINGS Only 15 of the 54 African countries reported on absolute blood pressure (BP) measures, elevated BP, pre- and/or hypertension. The reported hypertension prevalence ranged between 0.0 and 38.9%, while elevated BP and/or pre-hypertnesion ranged from 2.7 to 50.5%. Childhood BP nomograms are lacking across Africa and the rates of hypertension were based on guidelines developed in countries with the lowest to no number of children from African ancestry. The recent studies across Africa also showed little to no detail when reporting BP specific methodology. No recent data informing the use or effectiveness of antihypertensive agents in children and adolesents are available. Childhood hypertension is on the rise, while data from Africa remains vastly under-represented. Collaborative research, resources, and policies need to be strengthened in addressing the growing public health concern of childhood onset hypertension on this continent.
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Affiliation(s)
- A Craig
- SAMRC/Wits Developmental Pathways for Health Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Y Breet
- Hypertension in Africa Research Team (HART), North-West University, Private Bag X6001, Potchefstroom, 2520, South Africa
- MRC Research Unit for Hypertension and Cardiovascular Disease, North-West University, Potchefstroom, South Africa
| | - L F Gafane-Matemane
- Hypertension in Africa Research Team (HART), North-West University, Private Bag X6001, Potchefstroom, 2520, South Africa
- MRC Research Unit for Hypertension and Cardiovascular Disease, North-West University, Potchefstroom, South Africa
| | - S A Norris
- SAMRC/Wits Developmental Pathways for Health Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- School of Human Development and Health, University of Southampton, Southampton, UK
| | - R Kruger
- Hypertension in Africa Research Team (HART), North-West University, Private Bag X6001, Potchefstroom, 2520, South Africa.
- MRC Research Unit for Hypertension and Cardiovascular Disease, North-West University, Potchefstroom, South Africa.
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Craig A, Ware LJ, Mapanga W, Norris SA. A comparison of paediatric hypertension clinical practice guidelines and their ability to predict adult hypertension in an African birth cohort. J Hum Hypertens 2023; 37:455-462. [PMID: 35701669 PMCID: PMC10256606 DOI: 10.1038/s41371-022-00709-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 05/02/2022] [Accepted: 05/27/2022] [Indexed: 11/08/2022]
Abstract
It remains unclear which paediatric hypertension clinical practice guideline (CPG) should be applied in an African population. We, therefore, aimed to compare commonly used CPG (2017 AAP, 2016 ESH, 2004 Fourth Report) developed in high-income countries for use in South African children at four paediatric ages (children: 5 years, 8 years; adolescents: 13 years, 17 years) to determine which best predicts elevated blood pressure (BP) in adulthood (22 years, 28 years). Moreover, the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for each specific paediatric CPG was calculated across the age points. The 2017 AAP definition identified more children and adolescents with hypertension when compared to the 2004 Fourth Report and 2016 ESH guidelines. In computed hazards ratios, ages 8 years to 17 years, all three paediatric CPG significantly predicted the risk of elevated BP in young adulthood (p ≤ 0.032). However, sensitivity to predict elevated BP at age 22 years for all CPG was generally low (17.0%-33.0%) with higher specificity (87.4%-93.1%). Sensitivity increased at age 28 years (51.4%-70.1%), while specificity decreased (52.8%-65.1%). Both PPV and NPV at both adult age points varied widely (17.9%-79.9% and 29.3%-92.5% respectively). The performance of these paediatric CPG in terms of AUC were not optimal at both adult age points, however, the 2017 AAP definition at age 17 years met an acceptable level of performance (AUC = 0.71). Our results, therefore, highlight the need for more research to examine if an African-specific CPG would better identify high-risk children to minimise their trajectory towards adult hypertension.
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Affiliation(s)
- A Craig
- SAMRC/Wits Developmental Pathways for Health Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
- DSI-NRF Centre of Excellence in Human Development, University of the Witwatersrand, Johannesburg, South Africa.
| | - L J Ware
- SAMRC/Wits Developmental Pathways for Health Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- DSI-NRF Centre of Excellence in Human Development, University of the Witwatersrand, Johannesburg, South Africa
| | - W Mapanga
- SAMRC/Wits Developmental Pathways for Health Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- DSI-NRF Centre of Excellence in Human Development, University of the Witwatersrand, Johannesburg, South Africa
| | - S A Norris
- SAMRC/Wits Developmental Pathways for Health Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- DSI-NRF Centre of Excellence in Human Development, University of the Witwatersrand, Johannesburg, South Africa
- Global Health Research Institute, School of Health and Human Development, University of Southampton, Southampton, UK
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The impact of maternal hyperglycaemia first detected in pregnancy on offspring blood pressure in Soweto, South Africa. J Hypertens 2022; 40:969-977. [PMID: 35142740 DOI: 10.1097/hjh.0000000000003102] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND The long-term consequences for offspring born to mothers with hyperglycaemia first detected in pregnancy (HFDP) are not yet well understood and its influence on childhood blood pressure has not previously been assessed in sub-Saharan Africa. OBJECTIVE The objective of this study was to evaluate the association between maternal HFDP and offspring blood pressure in 3 to 6-year-old children in Soweto, South Africa. METHODS Oscillometric blood pressure was measured in 189 children born to mothers with and without HFDP diagnosed by 75 g 2-h oral glucose tolerance test. The 2017 AAP Guidelines for Childhood Hypertension were used as reference standard, and the term 'elevated blood pressure' referred to blood pressure readings above the 90th percentile for age, height and sex. The association between maternal HFDP and offspring blood pressure was analysed using multivariable linear regression. RESULTS Elevated blood pressure was identified in 49.7% of children. Maternal hyperglycaemia was not associated with offspring blood pressure when adjusted for offspring age, height and sex (SBP: 0.199, P = 0.888; DBP: 0.185, P = 0.837) or after multivariable adjustment (SBP: -0.286, P = 0.854; DBP: 0.215, P = 0.833). In the full model for SBP, child BMI age z-score was a significant predictor of blood pressure at 3-6 years (1.916, P = 0.008). CONCLUSION Although maternal HFDP was not associated with childhood blood pressure at 3-6 years, the prevalence of elevated blood pressure in this group of preschool-aged children is concerning. Future research is needed to further evaluate childhood obesity as a modifiable risk factor to reduce hypertension and cardiovascular risk in an African setting.
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Meer R, Boateng D, Klipstein-Grobusch K, Norris SA, Kagura J. Incidence and correlates of high blood pressure from childhood to adulthood: the Birth to Twenty study. J Hypertens 2022; 40:274-282. [PMID: 34475345 PMCID: PMC8728753 DOI: 10.1097/hjh.0000000000003004] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Revised: 08/05/2021] [Accepted: 08/08/2021] [Indexed: 11/25/2022]
Abstract
BACKGROUND There is growing evidence from high-income countries suggesting that hypertension developed in childhood and adolescence persists into adulthood. The objective of this study was to investigate the incidence and risk factors of high blood pressure (BP) in urban black children. METHODS We used data from the Birth to Twenty (BT20+) cohort in Johannesburg, South Africa constituting of children born in 1990 and who had their growth, development and blood pressure measured at six follow-up periods over the course of 13 years. High BP was classified as at least 95th percentile for age, sex and height. Incidence rate of high BP was calculated using survival analysis and risk factors were determined by use of Cox proportional hazard regression. RESULTS Over a follow-up period of 13 years, the overall incidence rate of high BP was 57 cases per 1000 person-years (95% CI 53.2-61.1). Risk for incident high BP increased with rapid relative weight gain in early childhood (hazard ratio =1.11, 95% CI 1.00-1.22), mid-childhood (hazard ratio = 1.13, 95% CI 1.03-1.24) and adolescence (hazard ratio = 1.21, 95% CI 0.99-1.47). Maternal parity significantly increased the risk for incident high BP (hazard ratio = 1.08, 95% CI 1.01-1.15). CONCLUSION Maternal parity and relative weight gain were determinants for incident high blood pressure in urban black South African children and adolescents. To reduce the high incidence and the disease burden of high BP, national programs should focus on promoting healthy lifestyle in early stages of life to prevent rapid weight gain and later cardiovascular disease risk. Further research is required to investigate whether incident high BP in childhood predict clinical outcomes in adulthood.
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Affiliation(s)
- Romain Meer
- Julius Global Health, Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands
| | - Daniel Boateng
- Julius Global Health, Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands
| | - Kerstin Klipstein-Grobusch
- Julius Global Health, Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands
- Department of Epidemiology and Biostatistics, School of Public Health, Faculty of Health Sciences
| | - Shane A. Norris
- SAMRC Developmental Pathways for Health Research Unit, Department of Paediatrics, School of Clinical Medicine, University of the Witwatersrand, Johannesburg, South Africa
- Global Health Research Institute, School of Human Development and Health, University of Southampton, UK
| | - Juliana Kagura
- Department of Epidemiology and Biostatistics, School of Public Health, Faculty of Health Sciences
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Arnaiz P, Müller I, Seelig H, Gerber M, Bosma J, Dolley D, Adams L, Degen J, Gall S, Joubert N, Nienaber M, Nqweniso S, Aerts A, Steinmann P, du Randt R, Walter C, Utzinger J, Pühse U. Practice Change Needed for the Identification of Pediatric Hypertension in Marginalized Populations: An Example From South Africa. Front Pediatr 2022; 10:877431. [PMID: 35633959 PMCID: PMC9130957 DOI: 10.3389/fped.2022.877431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 04/18/2022] [Indexed: 11/16/2022] Open
Abstract
INTRODUCTION Hypertension in children has increased globally over the past 20 years; yet, little is known about this issue among disadvantaged communities from low- and middle-income countries. Age-, sex-, and height-adjusted normative tables are the "gold" standard for the diagnosis and estimation of pediatric hypertension worldwide, but it is unclear whether the use of international standards is appropriate for all contexts. The purpose of this study was to evaluate and compare different international references to identify hypertension among South African school-aged children from disadvantaged communities. METHODS Blood pressure, weight, and height were measured in a cohort of 897 children aged 8-16 years from eight peri-urban schools in the Eastern Cape of South Africa. Cross-sectional prevalence of hypertension was calculated according to American, German, and global normative tables, as well as pseudo-normative data from the own study population. Isolated systolic hypertension and body mass index (BMI) were considered markers for cardiovascular disease. Multinomial logistic regression was used to compare the likelihood of blood pressure categorization with increasing BMI levels. RESULTS Hypertension prevalence ranged from 11.4% with the pseudo-normative study tables to 28.8% based on the German reference. Global guidelines showed the highest agreement both among international standards (92.5% with American guidelines) and with the study reference (72.5%). While the global and the American references presented higher systolic over diastolic hypertension rates (23.6 vs. 10.6% and 24.2 vs. 14.7%, respectively), the American guidelines predicted the highest increased risk for hypertension stage 2 [odds ratio, 1.72 (95% confidence interval: 1.43-2.07)] with raising levels of BMI. CONCLUSION Our results support the heterogeneity of blood pressure estimates found in the South African literature, and highlight the underrepresentation of African children in international guidelines. We call for caution in the use of international standards in different contexts and advocate for the development of normative tables that are representative of the South African pediatric population necessary to ensure an accurate identification of hypertension both from the clinical and epidemiological perspective.
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Affiliation(s)
- Patricia Arnaiz
- Department of Sport, Exercise and Health, University of Basel, Basel, Switzerland
| | - Ivan Müller
- Department of Sport, Exercise and Health, University of Basel, Basel, Switzerland
| | - Harald Seelig
- Department of Sport, Exercise and Health, University of Basel, Basel, Switzerland
| | - Markus Gerber
- Department of Sport, Exercise and Health, University of Basel, Basel, Switzerland
| | - Jacob Bosma
- Department of Human Movement Science, Nelson Mandela University, Gqeberha, South Africa
| | - Danielle Dolley
- Department of Human Movement Science, Nelson Mandela University, Gqeberha, South Africa
| | - Larissa Adams
- Department of Human Movement Science, Nelson Mandela University, Gqeberha, South Africa
| | - Jan Degen
- Department of Sport, Exercise and Health, University of Basel, Basel, Switzerland
| | - Stefanie Gall
- Department of Sport, Exercise and Health, University of Basel, Basel, Switzerland
| | - Nandi Joubert
- Department of Sport, Exercise and Health, University of Basel, Basel, Switzerland.,Swiss Tropical and Public Health Institute, Allschwil, Switzerland.,University of Basel, Basel, Switzerland
| | - Madeleine Nienaber
- Department of Human Movement Science, Nelson Mandela University, Gqeberha, South Africa
| | - Siphesihle Nqweniso
- Department of Human Movement Science, Nelson Mandela University, Gqeberha, South Africa
| | - Ann Aerts
- Novartis Foundation, Basel, Switzerland
| | - Peter Steinmann
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland.,University of Basel, Basel, Switzerland
| | - Rosa du Randt
- Department of Human Movement Science, Nelson Mandela University, Gqeberha, South Africa
| | - Cheryl Walter
- Department of Human Movement Science, Nelson Mandela University, Gqeberha, South Africa
| | - Jürg Utzinger
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland.,University of Basel, Basel, Switzerland
| | - Uwe Pühse
- Department of Sport, Exercise and Health, University of Basel, Basel, Switzerland
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Craig A, Gafane-Matemane L, Smith W, Mels C, Uys L, Breet Y, Brits S, Mokwatsi G, Hanssen H, Kruger R. Elevated blood pressure positively associates with alpha-1 microglobulin in prepubescent children: the ExAMIN Youth SA study. J Hypertens 2022; 40:136-142. [PMID: 34857706 DOI: 10.1097/hjh.0000000000002989] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
OBJECTIVES AND METHODS Hypertension is a growing health concern in childhood populations and individuals of African descent. As the kidneys play a significant role in blood pressure regulation, we compared alpha-1 microglobulin (A1M) as a marker of proximal tubular function between young healthy black and white children (n = 957; aged: 5-9 years) and explored its association with blood pressure. RESULTS The black children had higher levels of A1M (P < 0.001) and higher DBP (P < 0.001) when compared with their white counterparts. In multiple regression analysis, SBP (adj. R2 = 0.173, β = 0.151; P < 0.001) and DBP (adj. R2 = 0.110, β = 0.179; P < 0.001) associated positively with A1M in the black children. In binary logistic regression, each standard deviation increase in A1M increased the odds of having elevated blood pressure by 28% (P = 0.002) in the black group, independent of age, sex, BMI z-score and body height. No significance was reached in the white children. CONCLUSION Our findings highlight the importance of a marker of proximal tubular function, especially in children of black ethnicity, in the setting of elevated blood pressure. Early childhood screening for elevated blood pressure remains essential in order to promote primary prevention of hypertension and early onset kidney damage in children.
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Affiliation(s)
| | - Lebo Gafane-Matemane
- Hypertension in Africa Research Team (HART)
- MRC Research Unit for Hypertension and Cardiovascular Disease, North-West University, Potchefstroom, South Africa
| | - Wayne Smith
- Hypertension in Africa Research Team (HART)
- MRC Research Unit for Hypertension and Cardiovascular Disease, North-West University, Potchefstroom, South Africa
| | - Carina Mels
- Hypertension in Africa Research Team (HART)
- MRC Research Unit for Hypertension and Cardiovascular Disease, North-West University, Potchefstroom, South Africa
| | - Lisa Uys
- Hypertension in Africa Research Team (HART)
- MRC Research Unit for Hypertension and Cardiovascular Disease, North-West University, Potchefstroom, South Africa
| | - Yolandi Breet
- Hypertension in Africa Research Team (HART)
- MRC Research Unit for Hypertension and Cardiovascular Disease, North-West University, Potchefstroom, South Africa
| | | | - Gonste Mokwatsi
- Hypertension in Africa Research Team (HART)
- MRC Research Unit for Hypertension and Cardiovascular Disease, North-West University, Potchefstroom, South Africa
| | - Henner Hanssen
- Department of Sport, Exercise and Health, University of Basel, Basel, Switzerland
| | - Ruan Kruger
- Hypertension in Africa Research Team (HART)
- MRC Research Unit for Hypertension and Cardiovascular Disease, North-West University, Potchefstroom, South Africa
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Thapa J, Sundar Budhathoki S, Niraula SR, Pandey S, Thakur N, Pokharel PK. Prehypertension and its predictors among older adolescents: A cross-sectional study from eastern Nepal. PLOS GLOBAL PUBLIC HEALTH 2022; 2:e0001117. [PMID: 36962628 PMCID: PMC10021258 DOI: 10.1371/journal.pgph.0001117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 09/03/2022] [Indexed: 11/18/2022]
Abstract
Prehypertension is a state of transition between normal blood pressure and hypertension. Adolescent prehypertension is a strong predictor of hypertension in adults and is now considered for cardiovascular intervention or risk reduction. This study was conducted among adolescents to assess the burden of pre-hypertension and its predictors. A cross-sectional study was conducted among grade 11 and 12 students in three districts in eastern Nepal namely Jhapa, Morang and Sunsari. Sampling was done using a multistage stratified proportionate random method. A semi-structured questionnaire adapted from the WHO STEPwise approach to the non-communicable disease risk factor surveillance (STEPS) instrument was used as a study tool after modification and pre-testing in addition to the anthropometric and blood pressure measurements by the investigators. The prevalence of prehypertension was assessed along with the identification of its predictors through multivariable binary logistic regression modelling. A total of 806 participants aged 15 to 19 years, with 57.1% female, participated in the study. Prehypertension was found in 20.8% (24.6% in males and 18.0% in females) of the participants, while 7.1% of them were hypertensive (9.2% males and 5.4% females). Obesity and central obesity were seen among 6.3% and 17.7% of the respondents respectively. Age, sex, ethnicity and obesity were found to be significantly associated with prehypertension. A significant proportion of prehypertension was seen among the adolescent population along with a notable presence of risk factors such as smoking, alcohol consumption, obesity, and eating out. This warrants careful consideration and identification of relevant strategies to reduce the burden of prehypertension via school-based interventions to reduce the modifiable risk factors.
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Affiliation(s)
- Jeevan Thapa
- Department of Community Health Sciences, Patan Academy of Health Sciences, Lalitpur, Nepal
| | - Shyam Sundar Budhathoki
- Faculty of Medicine, Department of Primary Care and Public Health, School of Public Health, Imperial College London, London, United Kingdom
| | - Surya Raj Niraula
- School of Public Health and Community Medicine, B.P. Koirala Institute of Health Sciences, Dharan, Nepal
| | - Sagar Pandey
- B.P. Koirala Institute of Health Sciences, Dharan, Nepal
| | - Nishant Thakur
- Epidemiology and Disease Control Division, Teku, Kathmandu, Nepal
| | - Paras K Pokharel
- School of Public Health and Community Medicine, B.P. Koirala Institute of Health Sciences, Dharan, Nepal
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Firat S, Nogay NH. Association of blood pressure with dietary intake, physical activity, and anthropometric measurements in Turkish adolescents. Niger J Clin Pract 2021; 24:1616-1623. [PMID: 34782499 DOI: 10.4103/njcp.njcp_685_20] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Background Determining high blood pressure in childhood is an important step to reduce the risk of occurrence of high blood pressure-related diseases in adulthood. Aims This study aimed to assess the association of blood pressure with dietary intake, physical activity, and anthropometric measurements in Turkish adolescents. Patients and Methods This cross-sectional study included 370 students (202 females, 168 males) aged 14 to 18 years from one private and one public school in Kayseri, Turkey. Some anthropometric measurements and 24-hour dietary recall of the students were obtained. Their blood pressures were measured, and the International Physical Activity Questionnaire and the Mediterranean Diet Quality Index (KIDMED) were used. Results The body mass index (BMI) mean and waist/height ratio of the hypertensive group were significantly higher than those of the prehypertensive group, whereas their daily potassium, calcium, and magnesium intakes were significantly lower than those of the normotensive group. The percentage of individuals with very low diet quality was higher in the hypertensive group than in the normotensive group (P > 0.05). The percentage of participants with sufficient physical activity was higher in the normotensive group than in the prehypertensive and hypertensive groups. Conclusion Factors such as high BMI and waist/height rates; low calcium, magnesium, and potassium intakes with diet; insufficient physical activity; and low quality of diet might cause an increase in the blood pressure.
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Affiliation(s)
- S Firat
- Department of Nutrition and Dietetics, Kirklareli University College of Health, Kırklareli, Turkey
| | - N H Nogay
- Department of Nutrition and Dietetics, Erciyes University Faculty of Health Sciences, Kayseri, Turkey
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11
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Desai G, Niu Z, Luo W, Frndak S, Shaver AL, Kordas K. Low-level exposure to lead, mercury, arsenic, and cadmium, and blood pressure among 8-17-year-old participants of the 2009-2016 National Health and Nutrition Examination Survey. ENVIRONMENTAL RESEARCH 2021; 197:111086. [PMID: 33781774 PMCID: PMC8211235 DOI: 10.1016/j.envres.2021.111086] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 03/14/2021] [Accepted: 03/23/2021] [Indexed: 06/02/2023]
Abstract
BACKGROUND Dysregulation of systolic, diastolic blood pressure (SBP, DBP), and pulse pressure (PP) in children may predict elevated blood pressure (BP) in adulthood. Toxicant exposure is widely studied as a risk factor for high BP in adults, but not in children. We assessed the joint associations between lead (Pb), mercury (Hg), arsenic (As), and cadmium (Cd) exposure and SBP, DBP, and PP among 8-17 year-old participants (n = 1642) of the 2009-2016 National Health and Nutrition Examination Survey (NHANES). METHODS Participants with at least two BP measures were included. Urinary As and Cd were adjusted for urinary creatinine concentrations. Blood Pb, Hg, and urinary As, Cd were natural log-transformed. Bayesian Kernel Machine Regression (BKMR) analyses were conducted to assess the associations between the toxicant mixture and BP measures. Multivariable regression models assessed the associations between individual toxicants, and the four toxicants simultaneously with each of the outcomes. Interactions with sodium intake were tested. RESULTS Exposure to all toxicants was low, with median (5%, 95%) level: Pb, 0.57 (0.26, 1.60) μg/dL; Hg, 0.37 (0.19, 2.12) μg/L; As, 5.61 (1.37, 33.2) μg/g creatinine, Cd, 0.06 (0.03, 0.23) μg/g creatinine. Toxicant mixture showed a statistically significant, inverse association with DBP, but not other BP measures. Linear regressions revealed no association between toxicants, individually or together, and BP measures. No evidence of interaction of sodium intake with any of the toxicants was observed. CONCLUSIONS In a nationally representative sample of 8-17 year-olds, we found suggestive inverse association of the mixture of low-level Pb, Hg, As, and Cd, with DBP. Longitudinal studies with multiple toxicants are needed to understand the interactive effects of toxicants on children's BP.
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Affiliation(s)
- Gauri Desai
- Department of Epidemiology and Environmental Health, University at Buffalo, The State University of New York, USA.
| | - Zhongzheng Niu
- Department of Epidemiology and Environmental Health, University at Buffalo, The State University of New York, USA
| | - Wei Luo
- Department of Sociology, University at Buffalo, The State University of New York, USA
| | - Seth Frndak
- Department of Epidemiology and Environmental Health, University at Buffalo, The State University of New York, USA
| | - Amy L Shaver
- Department of Epidemiology and Environmental Health, University at Buffalo, The State University of New York, USA
| | - Katarzyna Kordas
- Department of Epidemiology and Environmental Health, University at Buffalo, The State University of New York, USA
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12
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Kruger R, Gafane-Matemane LF, Kagura J. Racial differences of early vascular aging in children and adolescents. Pediatr Nephrol 2021; 36:1087-1108. [PMID: 32444927 DOI: 10.1007/s00467-020-04593-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 04/27/2020] [Accepted: 04/28/2020] [Indexed: 12/19/2022]
Abstract
The prevalence of non-communicable disease (NCDs) is rising globally, with a large burden recorded in sub-Saharan countries and populations of black race/ethnicity. Accelerated vascular deterioration, otherwise known as early vascular aging (EVA), is the underlying factor for highly prevalent NCDs such as hypertension. The etiology of EVA is multifactorial with a central component being arterial stiffness with subsequent development of hypertension and cardiovascular complications. Although arterial stiffness develops with increasing age, many children and adolescents are subjected to the premature development of arterial stiffness, due to genetic or epigenetic predispositions, lifestyle and behavioral risk factors, and early life programming. Race/ethnic differences in pediatric populations have also been reported with higher aortic stiffness in black (African American) compared with age-matched white (European American) counterparts independent of blood pressure, body mass index, or socioeconomic status. With known evidence of race/ethnic differences in EVA, the pathophysiological mechanisms underlying graded differences in the programming of EVA are still sparse and rarely explored. This educational review aims to address the early life determinants of EVA in children and adolescents with a particular focus on racial or ethnic differences.
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Affiliation(s)
- Ruan Kruger
- Hypertension in Africa Research Team (HART), North-West University, Private Bag X6001, Potchefstroom, 2520, South Africa.
- MRC Research Unit for Hypertension and Cardiovascular Disease, North-West University, Potchefstroom, South Africa.
| | - Lebo Francina Gafane-Matemane
- Hypertension in Africa Research Team (HART), North-West University, Private Bag X6001, Potchefstroom, 2520, South Africa
- MRC Research Unit for Hypertension and Cardiovascular Disease, North-West University, Potchefstroom, South Africa
| | - Juliana Kagura
- Division of Epidemiology and Biostatistics, School of Public Health, University of the Witwatersrand, Johannesburg, South Africa
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13
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Ni Y, Szpiro A, Loftus C, Tylavsky F, Kratz M, Bush NR, LeWinn KZ, Sathyanarayana S, Enquobahrie DA, Davis R, Fitzpatrick AL, Sonney J, Zhao Q, Karr CJ. Associations Between Maternal Nutrition in Pregnancy and Child Blood Pressure at 4-6 Years: A Prospective Study in a Community-Based Pregnancy Cohort. J Nutr 2021; 151:949-961. [PMID: 33561258 PMCID: PMC8030724 DOI: 10.1093/jn/nxaa395] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 09/30/2020] [Accepted: 11/16/2020] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND The intrauterine environment may influence offspring blood pressure, with effects possibly extending into adulthood. The associations between prenatal nutrition and offspring blood pressure, alone or in combination with other sociodemographic or behavioral factors, are unclear. OBJECTIVES To investigate the associations of maternal dietary patterns and plasma folate concentrations with blood pressure in children aged 4-6 years, and assess the potential effect modifications by child sex, maternal race, pre-pregnancy overweight or obesity, maternal smoking, and breastfeeding. METHODS Participants were 846 mother-child dyads from the Conditions Affecting Neurocognitive Development and Learning in Early Childhood (CANDLE) study. Maternal nutrition was characterized by the Healthy Eating Index 2010 (HEI) scores and plasma folate concentrations in pregnancy. We calculated the systolic blood pressure (SBP) and diastolic blood pressure percentiles, incorporating sex, age, and height, and categorized children as either having high blood pressure (HBP; ≥90th percentile) or normal blood pressure. Linear regressions were performed to quantify the associations between maternal nutrition and continuous blood pressure percentiles, and Poisson regressions were used to estimate the incidence rate ratio (IRR) of binary HBP. We examined the effect modifications using interaction models. RESULTS Mean HEI scores and folate concentrations were 60.0 (SD, 11.3) and 23.1 ng/mL (SD, 11.1), respectively. Based on measurements at 1 visit, 29.6% of the children were defined as having HBP. Maternal HEI scores and plasma folate concentrations were not associated with child blood pressure percentiles or HBP in the full cohort. Among mothers self-identified as white, there was an inverse relationship between maternal HEI score and child SBP percentile (β, -0.40; 95%CI: -0.75 to -0.06). A maternal HEI score above 59 was associated with a reduced risk of HBP in girls (IRR, 0.53; 95% CI: 0.32-0.88). No modified associations by pre-pregnancy overweight or obesity, maternal smoking, or breastfeeding were indicated. CONCLUSIONS We found little evidence for effects of maternal nutrition during pregnancy on childhood blood pressure, but detected sex- and race-specific associations. The study contributes to the evolving scientific inquiry regarding developmental origins of disease.
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Affiliation(s)
- Yu Ni
- Department of Epidemiology, School of Public Health, University of Washington, Seattle, WA, USA
| | - Adam Szpiro
- Department of Biostatistics, School of Public Health, University of Washington, Seattle, WA, USA
| | - Christine Loftus
- Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, Seattle, WA, USA
| | - Frances Tylavsky
- Department of Preventive Medicine, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Mario Kratz
- Department of Epidemiology, School of Public Health, University of Washington, Seattle, WA, USA
- Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Nicole R Bush
- Department of Psychiatry and Behavioral Sciences, School of Medicine, University of California, San Francisco, San Francisco, CA, USA
- Department of Pediatrics, School of Medicine, University of California, San Francisco, San Francisco, CA, USA
| | - Kaja Z LeWinn
- Department of Psychiatry and Behavioral Sciences, School of Medicine, University of California, San Francisco, San Francisco, CA, USA
| | - Sheela Sathyanarayana
- Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, Seattle, WA, USA
- Department of Pediatrics, School of Medicine, University of Washington, Seattle, WA, USA
- Seattle Children's Research Institute, Seattle, WA, USA
| | - Daniel A Enquobahrie
- Department of Epidemiology, School of Public Health, University of Washington, Seattle, WA, USA
| | - Robert Davis
- Center for Biomedical Informatics, University of Tennessee Health Science Center, Memphis, TN, USA
- Department of Pediatrics, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Annette L Fitzpatrick
- Department of Epidemiology, School of Public Health, University of Washington, Seattle, WA, USA
- Department of Family Medicine, School of Medicine, University of Washington, Seattle, WA, USA
- Department of Global Health, School of Public Health, University of Washington, Seattle, WA, USA
| | - Jennifer Sonney
- Department of Child, Family, and Population Health Nursing, School of Nursing, University of Washington, Seattle, WA, USA
| | - Qi Zhao
- Department of Preventive Medicine, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Catherine J Karr
- Department of Epidemiology, School of Public Health, University of Washington, Seattle, WA, USA
- Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, Seattle, WA, USA
- Department of Pediatrics, School of Medicine, University of Washington, Seattle, WA, USA
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14
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Matjuda EN, Engwa GA, Anye SNC, Nkeh-Chungag BN, Goswami N. Cardiovascular Risk Factors and Their Relationship with Vascular Dysfunction in South African Children of African Ancestry. J Clin Med 2021; 10:jcm10020354. [PMID: 33477761 PMCID: PMC7832309 DOI: 10.3390/jcm10020354] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 12/31/2020] [Accepted: 01/02/2021] [Indexed: 12/31/2022] Open
Abstract
Vascular dysfunction is known to be an initiator of the development and progression of cardiovascular diseases (CVDs). However, there is paucity of information on the relationship of vascular dysfunction with cardiovascular risk factors in children of African ancestry. This study investigated the relationship between cardiovascular risk factors and vascular function in South African children of African ancestry. A cross-sectional study on 6–9-year-old children in randomly selected rural and urban schools of the Eastern Cape Province of South Africa was conducted. General anthropometric indices were measured, followed by blood pressure (BP) measurements. The pulse wave velocity (PWV) was measured using a Vicorder. Albumin to creatinine ratio (ACR), asymmetric dimethylarginine (ADMA), 8-hydroxy-2deoxyguanosine (8-OHdG) and thiobarbituric acid reactive substance (TBARS) were assayed in urine. Children from urban settings (10.8%) had a higher prevalence of overweight/obesity than their rural counterparts (8.5%) while the prevalence of elevated/high blood pressure was higher in rural (23.2%) than urban children (19.0%). Mean arterial blood pressure (MAP) and diastolic blood pressure (DBP) increased with increasing PWV (p < 0.05). Body mass index (BMI), diastolic blood pressure (DBP) and mean arterial blood pressure (MAP) positively associated (p < 0.05) with PWV. Creatinine, albumin and ACR significantly (p < 0.005) increased with increasing ADMA. ADMA associated positively (p < 0.05) with creatinine and 8-OHdG. In conclusion, vascular dysfunction was associated with obesity, high blood pressure, oxidative stress and microalbuminuria in South African children of African ancestry.
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Affiliation(s)
- Edna N. Matjuda
- Department of Human Biology, Faculty of Health Sciences, Walter Sisulu University PBX1, Mthatha 5117, South Africa;
| | - Godwill A. Engwa
- Department of Biological and Environmental Sciences, Faculty of Natural Sciences, Walter Sisulu University PBX1, Mthatha 5117, South Africa;
| | - Samuel Nkeh Chungag Anye
- MBCHB Programme, Faculty of Health Sciences, Walter Sisulu University PBX1, Mthatha 5117, South Africa;
| | - Benedicta N. Nkeh-Chungag
- Department of Biological and Environmental Sciences, Faculty of Natural Sciences, Walter Sisulu University PBX1, Mthatha 5117, South Africa;
- Correspondence:
| | - Nandu Goswami
- Physiology Division, Otto Loewi Research Center for Vascular Biology, Immunology and Inflammation, Medical University of Graz, Neue Stiftingtalstrasse 6, 8036 Graz, Austria;
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15
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Matjuda EN, Sewani-Rusike CR, Anye SNC, Engwa GA, Nkeh-Chungag BN. Relationship between High Blood Pressure and Microalbuminuria in Children Aged 6-9 Years in a South African Population. CHILDREN (BASEL, SWITZERLAND) 2020; 7:E131. [PMID: 32906740 PMCID: PMC7552714 DOI: 10.3390/children7090131] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Revised: 08/31/2020] [Accepted: 09/02/2020] [Indexed: 11/16/2022]
Abstract
Though the association between high blood pressure and microalbuminuria is well established in adults, there is a paucity of information on microalbuminuria in children. This study investigated the relationship between high blood pressure and microalbuminuria in 6-9-year-old children. A cross-sectional study, which included 306 primary school children of age 6-9 years old from urban areas (n = 154) and rural areas (n = 152) of the Eastern Cape Province of South Africa, was conducted. Participants' anthropometric data were determined and systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR) were measured and converted to BP percentiles for age, sex and height. Creatinine and albumin concentrations were assayed in early morning midstream urine and the albumin to creatinine ratio (ACR) was calculated. There was a 42.8% prevalence of elevated blood pressure/high blood pressure (E-BP/H-BP) and a 10.1% prevalence of microalbuminuria. Among the 131 children with E-BP/H-BP, 17 had elevated ACR with a prevalence of 13.95%. SBP and HR increased with increasing range of ACR and, furthermore, SBP was significantly (p < 0.05) higher in children with moderately and severely increased ACR. SBP was associated with ACR and increased SBP predicted microalbuminuria (R2 = 0.42, adj R2 = 0.039, B: 0.120, p = < 0.05). In conclusion, microalbuminuria was present in 6-9-year-old South African children of African Ancestry and a weak association was observed with SBP in children.
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Affiliation(s)
- Edna Ngoakoana Matjuda
- Department of Human Biology, Faculty of Health Sciences, Walter Sisulu University PBX1, 5117 Mthatha, South Africa; (E.N.M.); (C.R.S.-R.)
| | - Constance R. Sewani-Rusike
- Department of Human Biology, Faculty of Health Sciences, Walter Sisulu University PBX1, 5117 Mthatha, South Africa; (E.N.M.); (C.R.S.-R.)
| | - Samuel Nkeh Chungag Anye
- MBCHB Programme, Faculty of Health Sciences, Walter Sisulu University PBX1, 5117 Mthatha, South Africa;
| | - Godwill Azeh Engwa
- Department of Biological and Environmental Sciences, Faculty of Natural Sciences, Walter Sisulu University PBX1, 5117 Mthatha, South Africa;
| | - Benedicta Ngwechi Nkeh-Chungag
- Department of Biological and Environmental Sciences, Faculty of Natural Sciences, Walter Sisulu University PBX1, 5117 Mthatha, South Africa;
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16
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Masocha V, Monyeki MA, Czyż SH. Longitudinal relationships between changes in body composition and changes in selected metabolic risk factors (abdominal obesity and blood pressure) among South African adolescents. PeerJ 2020; 8:e9331. [PMID: 32612883 PMCID: PMC7319020 DOI: 10.7717/peerj.9331] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 05/19/2020] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Incidence of childhood high blood pressure (BP) is increasing worldwide. This study examined the longitudinal relationship between changes in body composition (i.e. body mass index (BMI), waist circumference (WC) and percentage body fat) and selected metabolic risk factors (abdominal obesity and BP) among adolescents from the Tlokwe municipality in the North West Province of South Africa. METHOD One hundred and eight-six adolescents (81 boys and 105 girls) aged 14 to 16 years participated in the study. Body composition was measured following the International Society of the Advancement of Kinanthropometry standard procedures. BMI, abdominal obesity using WC measurement, and resting BP were determined. Analysis of variance (ANOVA) for repeated measures was calculated to determine changes in anthropometric measures and body composition as well as changes in BP. Additionally, Univariate analysis of variance with repeated measures and participants as a random sample was applied. Diastolic BP (DBP) and systolic BP (SBP) were used as dependent variables and sex, age, BMI, WC, and waist-to-height ratio as independent variables. RESULTS Significant changes were found for stature, BMI, body mass, WC, SBP, and DBP. BMI for the total group was significant and positively related to abdominal obesity in 2012 (r = 0.55; p < 0.01) and in 2013 (r = 0.77; p < 0.01) and to SBP (r = 0.26; p < 0.05) in 2012 and (r = 0.17; p = 0.43) in 2013. BMI among the boys was significantly and positively related to abdominal obesity in 2012 (r = 0.83; p < 0.01) and 2013 (r = 0.91; p < 0.01). For the girls, BMI was significantly and positively related to abdominal obesity (r = 0.49; p < 0.01) and to SBP (r = 0.32; p = 0.05) in 2012. Boys with a higher WC in 2012 had significantly increased DBP (p < 0.05). Boys measured in 2012 with greater WC and BMI show a significant increase in SBP. CONCLUSIONS BMI was positively related to BP and abdominal obesity over time. Relatively high BMI and abdominal obesity significantly increased the likelihood of elevated BP over time, especially in boys. BMI was a predictor of abdominal obesity in boys, while in girls, BMI was a predictor of both abdominal obesity and SBP. In view of the future health implications of both abdominal obesity and elevated BP, urgent strategic interventions programs aimed at increasing physical activity and advocating for well-balanced dietary practices as well as importance of keeping normal blood pressure among South African adolescents are needed.
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Affiliation(s)
- Vincent Masocha
- Physical Activity, Sport, and Recreation Research Focus Group, North-West University, Potchefstroom, South Africa
| | - Makama Andries Monyeki
- Physical Activity, Sport, and Recreation Research Focus Group, North-West University, Potchefstroom, South Africa
| | - Stanisław H. Czyż
- Physical Activity, Sport, and Recreation Research Focus Group, North-West University, Potchefstroom, South Africa
- Faculty of Physical Education, University School of Physical Education in Wrocław, Wrocław, Poland
- Faculty of Sport Studies, Masaryk University, Brno, Czech Republic
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17
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Craig A, Mels CMC, Schutte AE, Tsikas D, Kruger R. Nitric oxide-related markers link inversely to blood pressure in black boys and men: the ASOS and African-PREDICT studies. Amino Acids 2020; 52:639-648. [PMID: 32303905 DOI: 10.1007/s00726-020-02842-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 04/09/2020] [Indexed: 12/16/2022]
Abstract
Nitric oxide plays an important role in maintaining endothelial function, while increased oxidative stress may lead to nitric oxide inactivation and cardiovascular disease. If nitric oxide biosynthesis/bioavailability is already suppressed early in life, it may potentially predispose an individual to the early development of cardiovascular disease. We therefore aimed to identify differences in nitric oxide-related markers (urinary nitrate, nitrite and the nitrate-to-nitrite ratio (UNOxR)) between young black and white individuals, and whether these markers are associated with blood pressure and carotid intima media thickness. We included black and white healthy boys (n = 80; aged 6-8 years) and men (n = 510; 20-30 years) and measured blood pressure and carotid intima media thickness, along with urinary biochemical markers including nitrate and nitrite. The black boys and men had lower nitrate and UNOxR (all p ≤ 0.003) than their white counterparts. In single and multiple regression analyses, we found an inverse association of diastolic blood pressure in the black boys (adj. R2 = 0.27; β = -0.32; p = 0.030), and systolic blood pressure in black men (adj. R2 = 0.07; β = -0.13; p = 0.036) with nitrate. Carotid intima media thickness associated inversely with UNOxR in the black men (adj. R2 = 0.02; β = -0.14; p = 0.023), but not in the boys. Lower urinary nitrate in black boys and young men was associated negatively with blood pressure, suggesting that potentially lower nitric oxide bioavailability in young black individuals may contribute to hypertension development in later life.
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Affiliation(s)
- Ashleigh Craig
- Hypertension in Africa Research Team (HART), North-West University, Potchefstroom, South Africa
| | - Catharina M C Mels
- Hypertension in Africa Research Team (HART), North-West University, Potchefstroom, South Africa.,MRC Research Unit for Hypertension and Cardiovascular Disease, North-West University, Potchefstroom, South Africa
| | - Aletta E Schutte
- Hypertension in Africa Research Team (HART), North-West University, Potchefstroom, South Africa.,MRC Research Unit for Hypertension and Cardiovascular Disease, North-West University, Potchefstroom, South Africa.,Faculty of Medicine, University of New South Wales, The George Institute for Global Health, Sydney, Australia
| | - Dimitrios Tsikas
- Institute of Toxicology, Core Unit Proteomics, Hannover Medical School, Hannover, Germany
| | - Ruan Kruger
- Hypertension in Africa Research Team (HART), North-West University, Potchefstroom, South Africa. .,MRC Research Unit for Hypertension and Cardiovascular Disease, North-West University, Potchefstroom, South Africa.
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18
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Association of Hypertension and Obesity with Risk Factors of Cardiovascular Diseases in Children Aged 6-9 Years Old in the Eastern Cape Province of South Africa. CHILDREN-BASEL 2020; 7:children7040025. [PMID: 32231008 PMCID: PMC7230217 DOI: 10.3390/children7040025] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 03/02/2020] [Accepted: 03/11/2020] [Indexed: 12/26/2022]
Abstract
Cardiovascular disease (CVD) risk factors are known to begin early in life, but limited data on the relationship of obesity and hypertension with other known CVD risk factors, such as endothelial dysfunction, oxidative stress, and chronic low-grade inflammation is available on children. In this cross-sectional study involving 6–9 years old school children aged from the Eastern Cape Province of South Africa the relationship between obesity/hypertension and other risk factors for CVDs was investigated. General anthropometric parameters were measured, followed by blood pressure (BP) measurements and pulse wave velocity (PWV). Urine samples were collected for the determination of albumin, creatinine, asymmetric dimethylarginine (ADMA), 8-hydroxy-2deoxyguanosine (8-OHdG), and thiobarbituric acid-reactive substance (TBARS). Overweight/obesity (19.28%) and pre-hypertension/hypertension (42.16%) were prevalent in children. Mid-upper arm circumference (MUAC), a marker of obesity, was positively correlated with ADMA, while ADMA and PWV were significantly different (p < 0.05) between hypertensive and normotensive children. Also, TBARS and 8-OHdG were significantly (p < 0.05) increased in hypertensive subjects. Creatinine was significantly (p < 0.05) increased in obese, as well as in hypertensive children, and positively associated with waist circumference (WC) and neck circumference (NC). In conclusion, obesity and hypertension were associated with renal-cardiovascular disease risk, while oxidative stress showed a possible association with obesity in 6 to 9 year old South African children of African descent. This suggests that South African children of African descent may be becoming more prone to developing CVDs, and therefore may require early intervention for the prevention of CVDs in the near future.
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19
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An Ethnic Comparison of Arginine Dimethylation and Cardiometabolic Factors in Healthy Black and White Youth: The ASOS and African-PREDICT Studies. J Clin Med 2020; 9:jcm9030844. [PMID: 32244968 PMCID: PMC7141317 DOI: 10.3390/jcm9030844] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 03/12/2020] [Accepted: 03/18/2020] [Indexed: 12/20/2022] Open
Abstract
Proteinic arginine dimethylation (PADiMe) is a major post-translational modification. Proteolysis of asymmetric and symmetric PADiMe products releases asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA), respectively, two endogenous atherogenic substances. SDMA, ADMA, and its major metabolite dimethylamine (DMA) are eliminated by the kidney. The urinary concentrations of DMA+ADMA, SDMA, and DMA+ADMA+SDMA are useful measures of the whole-body asymmetric and symmetric PADiMe, respectively. Urinary (DMA+ADMA)/SDMA is an index of the asymmetric to symmetric PADiMe balance. In two bi-ethnic studies, the ASOS (39 black boys, 41 white boys) and the African-PREDICT (292 black young men, 281 white young men) studies, we investigated whether ethnicity is a major determinant of PADiMe, and whether PADiMe is associated with blood pressure and ethnicity-dependent growth and inflammatory factors, including HDL. DMA, ADMA, and SDMA were measured in spot urine samples by gas chromatography-mass spectrometry, and their excretion was corrected for creatinine excretion. In black boys, creatinine-corrected DMA, DMA+ADMA, and DMA+ADMA+SDMA concentrations were lower by 11.7%, 9.5%, and 7.6% (all p < 0.05), respectively, compared to the white boys, and 3.4%, 2.0%, and 1.8% lower (all p < 0.05), respectively, in black compared to white men. (DMA+ADMA)/SDMA did not differ between black boys and black men, but was higher in white boys compared to white men. ADMA did not differ between black and white boys, or between black and white men. Creatinine-corrected SDMA excretion was lower in black boys compared to white boys (by 8%) and to white men (by 3.1%). None of the PADiMe indices were associated with blood pressure in either study. IGF-binding protein 3 correlated inversely with all PADiMe indices in the black men only. Our study showed that asymmetric proteinic arginine dimethylation is higher in white boys than in black boys, and that this difference disappears in adulthood. ADMA metabolism and SDMA excretion were lower in the black subjects compared to the white subjects, suggesting ethnicity-dependent hepatic and renal elimination of ADMA and SDMA in the childhood. The results of our study may have clinical relevance beyond atherosclerosis, such as in growth and inflammation, which have not been sufficiently addressed thus far.
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Chelo D, Mah EM, Chiabi EN, Chiabi A, Koki Ndombo PO, Kingue S, Obama MT. Prevalence and factors associated with hypertension in primary school children, in the centre region of Cameroon. Transl Pediatr 2019; 8:391-397. [PMID: 31993352 PMCID: PMC6970110 DOI: 10.21037/tp.2019.03.02] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 03/29/2019] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND There has been a progressive increase in hypertension among children and adolescents over the years. Hypertension in childhood is influenced by various risk factors including; childhood obesity, lifestyle and hereditary factors. This study is aimed at assessing the prevalence of hypertension and elevated blood pressure (BP); as well as the associated factors to hypertension among primary school children in a rural setting in the, Centre Region of Cameroon. METHODS A cross sectional study was carried out from November 2017 to May 2018 in 13 primary schools in Mbankomo subdivision. A two staged cluster sampling technique was used to select participants: the first stage we conveniently selected 13 out of 71 (18%) primary schools in the study area by probability proportionate to size since the subdivision does not have an equal number of primary schools in the rural and semi-urban areas. In the second stage, we also used probability proportional to size to randomly select participants from the 13 clusters because the classes did not have equal number of students. We randomly selected 13% pupils enrolled in each class of the 13 schools. BP and anthropometric measurements were taken, together with socio-demographic characteristics, lifestyle and past history. RESULTS The overall prevalence of hypertension among the 822 pupils sampled was 1.6% (with 1.5% in stage I and 0.1% in stage II) and that of elevated BP was 8.1%, with a systolic predominance of 1.6%. SBP and DBP had a significant positive correlation with age (r=0.17; P=0.000 and r=0.07; P=0.000 respectively) and BMI (r=0.18; P=0.000 and r=0.11; P=0.000 respectively). The associated risk factors for hypertension were: the pupil's age >10 years (95% CI: 1.2581-33.1841; P=0.0254), family history of overweight (95% CI: 1.6906-32.9401; P=0.008), and excess weight (95% CI: 2.5094-40.7063; P=0.0011), and being born at term (P=0.0004) as a protecting factor. CONCLUSIONS This study revealed a high prevalence of hypertension among primary school children in rural areas, with a number of preventable risk factors. Considering the risk factors found, children should be educated on proper nutrition, and the need for physical exercises at home and in school to avoid overweight and obesity.
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Affiliation(s)
- David Chelo
- Faculty of Medicine and Biomedical Sciences, University of Yaounde I, Yaounde, Cameroon
| | - Evelyn M Mah
- Faculty of Medicine and Biomedical Sciences, University of Yaounde I, Yaounde, Cameroon
| | - Edmond N Chiabi
- Faculty of Medicine and Biomedical Sciences, University of Yaounde I, Yaounde, Cameroon
| | - Andreas Chiabi
- Faculty of Medicine and Biomedical Sciences, University of Yaounde I, Yaounde, Cameroon
| | | | - Samuel Kingue
- Faculty of Medicine and Biomedical Sciences, University of Yaounde I, Yaounde, Cameroon
| | - Marie Therese Obama
- Faculty of Medicine and Biomedical Sciences, University of Yaounde I, Yaounde, Cameroon
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Brackmann LK, Buck C, Nyangasa MA, Kelm S, Sheikh M, Hebestreit A. Anthropometric and Biochemical Predictors for Hypertension in a Cross-Sectional Study in Zanzibar, Tanzania. Front Public Health 2019; 7:338. [PMID: 31824908 PMCID: PMC6881248 DOI: 10.3389/fpubh.2019.00338] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Accepted: 10/29/2019] [Indexed: 01/11/2023] Open
Abstract
Background: Aim of this study was to describe the proportion of hypertension among Zanzibari of different age-groups and to detect possible correlates of this non-communicable disease. Methods: In 2013 a cross-sectional survey was conducted in Unguja Island, Zanzibar. A total of 235 randomly selected households, including 1,229 (2 to 95 years) eligible study participants, were examined. Association between objectively assessed obesity markers, salt intake and hypertension were investigated. Estimates of 24 h sodium and potassium excretion from a single morning spot urine specimen were calculated and used as surrogate for salt intake. The association between overweight/obesity and hypertension in different age-groups was assessed in multilevel logistic regression models. Further associations between salt intake and hypertension were analyzed. Results: Measures of systolic and diastolic blood pressure as well as proportion of overweight/obesity and hypertension both increased with age. Overweight and obesity were significantly associated with hypertension in adults. Moreover, thinness seems to be associated with hypertension as well. We observed a significantly reduced chance of hypertension for higher urinary sodium-to-potassium compared to a lower ratio in children. Conclusion: Overweight/obesity and hypertension were highly prevalent (>47% of adults >40 years are overweight or obese and >69% are hypertensive in the same age group) in our sample. Weight status was confirmed as a correlate of high blood pressure in our sample from Zanzibar, Tanzania. To early and effectively prevent related severe cardiovascular outcomes, screening strategies but also monitoring strategies are required for this population.
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Affiliation(s)
- Lara Kim Brackmann
- Leibniz Institute for Prevention Research and Epidemiology - BIPS, Department of Epidemiological Methods and Etiological Research, Bremen, Germany
| | - Christoph Buck
- Leibniz Institute for Prevention Research and Epidemiology - BIPS, Department of Biometry and Data Mangement, Bremen, Germany
| | - Maria Adam Nyangasa
- Leibniz Institute for Prevention Research and Epidemiology - BIPS, Department of Epidemiological Methods and Etiological Research, Bremen, Germany
| | - Soerge Kelm
- Center for Biomolecular Interactions Bremen, Faculty for Biology and Chemistry, University Bremen, Bremen, Germany
| | - Mohammed Sheikh
- Environmental Analytical Chemistry and Eco-toxicology Lab, State University of Zanzibar, Zanzibar, Tanzania
| | - Antje Hebestreit
- Leibniz Institute for Prevention Research and Epidemiology - BIPS, Department of Epidemiological Methods and Etiological Research, Bremen, Germany
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Persistence of elevated blood pressure during childhood and adolescence: a school-based multiple cohorts study. J Hypertens 2019. [PMID: 29517559 DOI: 10.1097/hjh.0000000000001699] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
OBJECTIVE Blood pressure (BP) screening is advocated in children. However, identification of children with sustained elevated BP is difficult because of high BP variability. We assessed the tracking of BP and the persistence of elevated BP across childhood and adolescence. METHODS Three cohorts of children from schools in the Seychelles were examined on two occasions at 3-4-year intervals. Obesity was defined as BMI at least 95th sex-specific, and age-specific percentile. On each visit, BP was based on the average of two readings and elevated BP was defined as BP at least 95th sex-specific, age-specific, and height-specific percentile. RESULTS Data was collected in 4519 children of mean ages of 5.5 and 9.2 years, 6065 of ages of 9.2 and 12.5 years, and 5967 of ages of 12.5 and 15.6 years, respectively. Prevalence of elevated BP was 10% at age 5.5 years, 10% at 9.2 years, 7% at 12.5 years, and 9% at 15.6 years, respectively. Among children with elevated BP at the initial visit, the proportions who had elevated BP at the subsequent visit 3-4 years later was 13% between ages of 5.5 and 9.2 years, 19% between 9.2 and 12.5 years, and 27% between 12.5 and 15.6 years. These proportions were higher among obese children with elevated BP, that is, 33, 35, and 39%, in each cohort, respectively. Tracking coefficients were slightly larger for SBP (range of tracking coefficients: 0.23-0.40) than for DBP (range: 0.19-0.35), and increased with age. By comparisons, tracking coefficients for BMI were much higher (range: 0.74-0.84). CONCLUSION During childhood and adolescence, having an elevated BP on one occasion is a weak predictor of elevated BP 3-4 years later. Tracking is, however, larger in older and obese children than in younger and nonobese children.
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Is the cardiovascular health of South Africans today comparable with African Americans 45 years ago? J Hypertens 2019; 37:1606-1614. [PMID: 30950976 DOI: 10.1097/hjh.0000000000002082] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVES Hypertension occurs frequently among black populations around the world. In the United States (US) health system, interventions since the 1960s resulted in improvements in hypertension awareness, management and control among African Americans. This is in stark contrast to current health systems in African countries. To objectively assess the current situation in South Africa, we compared the cardiovascular health status of African Americans from 1960 to 1980 to black South Africans from recent years, as there is potential to implement best practices from the US. We also reviewed the recent cardiovascular health changes of a South African population over 10 years. METHODS Men and women were included from three studies performed in the United States (Evans County Heart Study; Charleston Heart Study; NHANES I and II) and one in South Africa (PURE, North West Province). We compared blood pressure (BP), BMI, cholesterol, diabetes and smoking status. RESULTS Age-adjusted SBP and DBP of South African men were lower than US studies conducted from 1960 to 1971 (Evans County; Charleston; NHANES I; all P < 0.001) but similar to NHANES II (P = 0.987) conducted in 1976. South African women had lower SBP than all four of the US studies (all P < 0.001); their DBP was lower than Evans County and Charleston studies, but similar to NHANES I and II. Reviewing South African data, BMI increased steeply over 10 years in women (P < 0.001) but not men (P = 0.451). CONCLUSION Blood pressure of South Africans is lower than African Americans from the 1960s, but comparable for 1970s to 1980s. With obesity of South African women rising sharply, escalating figures for hypertension and diabetes are anticipated.
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Nsanya MK, Kavishe BB, Katende D, Mosha N, Hansen C, Nsubuga RN, Munderi P, Grosskurth H, Kapiga S. Prevalence of high blood pressure and associated factors among adolescents and young people in Tanzania and Uganda. J Clin Hypertens (Greenwich) 2019; 21:470-478. [PMID: 30811099 PMCID: PMC8030556 DOI: 10.1111/jch.13502] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 01/09/2019] [Accepted: 01/21/2019] [Indexed: 11/30/2022]
Abstract
We conducted a cross-sectional study among school/college students in Tanzania and Uganda to determine the prevalence of high blood pressure (BP) and associated factors. Participants were classified to have high BP if they had pre-hypertension or hypertension. Interviews were done using the WHO STEPS instrument. Using data from both countries (n = 1596), the overall prevalence of high BP was 40% (95% CI: 37-42). The prevalence of pre-hypertension was 29% (95% CI: 26-31) and that of hypertension was 11% (95% CI: 10-13). High BP was independently associated with obesity (aOR = 6.7, 95% CI: 2.2-20.0), male sex (aOR = 3.2, 95% CI: 2.4-4.4), and among males aged above 20 years (aOR = 5.5, 95% CI: 2.9-10.5). Consumption of fruits/vegetables was associated with decreased odds for high BP (aOR = 0.7, 95% CI: 0.50-0.98). The increasing burden of pre-hypertension across age groups could explain the early onset of hypertension and cardiovascular diseases (CVDs) among young African adults. There is a need for longitudinal studies to explore the drivers of pre-hypertension in East African adolescents.
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Affiliation(s)
- Mussa K. Nsanya
- Mwanza Intervention Trials Unit/National Institute for Medical ResearchMwanzaTanzania
| | - Bazil B. Kavishe
- Mwanza Intervention Trials Unit/National Institute for Medical ResearchMwanzaTanzania
| | - David Katende
- Uganda Virus Research Unit/Medical Research UnitEntebbeUganda
| | - Neema Mosha
- Mwanza Intervention Trials Unit/National Institute for Medical ResearchMwanzaTanzania
| | - Christian Hansen
- Mwanza Intervention Trials Unit/National Institute for Medical ResearchMwanzaTanzania
- London School of Hygiene and Tropical MedicineLondonUK
| | | | - Paula Munderi
- Uganda Virus Research Unit/Medical Research UnitEntebbeUganda
| | - Heiner Grosskurth
- Mwanza Intervention Trials Unit/National Institute for Medical ResearchMwanzaTanzania
- London School of Hygiene and Tropical MedicineLondonUK
| | - Saidi Kapiga
- Mwanza Intervention Trials Unit/National Institute for Medical ResearchMwanzaTanzania
- London School of Hygiene and Tropical MedicineLondonUK
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Lule SA, Namara B, Akurut H, Lubyayi L, Nampijja M, Akello F, Tumusiime J, Aujo JC, Oduru G, Mentzer AJ, Smeeth L, Elliott AM, Webb EL. Blood pressure risk factors in early adolescents: results from a Ugandan birth cohort. J Hum Hypertens 2019; 33:679-692. [PMID: 30804461 PMCID: PMC6760975 DOI: 10.1038/s41371-019-0178-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 01/25/2019] [Accepted: 02/11/2019] [Indexed: 01/01/2023]
Abstract
We aimed to investigate life-course factors associated with blood pressure (BP) among Ugandan adolescents. Between 9th April 2003 and 24th November 2005, 2507 pregnant women from Entebbe municipality and Katabi sub-county were enrolled into a deworming trial. The resulting 2345 live-born offspring were followed to age 10 or 11 years, when between 20th May 2014 to 16th June 2016, BP was measured following standard protocols. Factors associated with BP were assessed using multivariable linear regression. BP was measured in 1119 adolescents with a median age of 10.2 years. Mean systolic BP and diastolic BP was 105.9 mmHg (standard deviation (SD) 8.2) and 65.2 mmHg (SD 7.3), respectively. Maternal gestational body mass index (BMI), higher maternal education status and family history of hypertension were positively associated with adolescent BP. Childhood (age ≤5 years) malaria was associated with lower adolescent systolic BP. Factors measured at time of BP measurement positively associated with systolic BP were age, BMI, waist circumference and Trichuris trichiura (whipworm) infection; higher vegetable consumption was associated with lower systolic BP. Results for diastolic BP were similar, except higher fruit, rather than higher vegetable consumption was associated with lower diastolic BP and there was no association with waist circumference or Trichuris trichiura infection. In summary, life-course exposures were associated with adolescent BP in this tropical birth cohort. Malaria early in life could impact later BP. Interventions initiated early in life targeting individuals with family history of hypertension, aiming to reduce adiposity (in pregnancy and adolescence) and promoting fruit and vegetable consumption might contribute to reducing the risk of high BP and subsequent cardiovascular diseases.
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Affiliation(s)
- Swaib A Lule
- London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK. .,MRC/UVRI & LSHTM Uganda Research Unit, P.O. Box 49, Entebbe, Uganda.
| | - Benigna Namara
- MRC/UVRI & LSHTM Uganda Research Unit, P.O. Box 49, Entebbe, Uganda
| | - Helen Akurut
- MRC/UVRI & LSHTM Uganda Research Unit, P.O. Box 49, Entebbe, Uganda
| | - Lawrence Lubyayi
- MRC/UVRI & LSHTM Uganda Research Unit, P.O. Box 49, Entebbe, Uganda
| | | | - Florence Akello
- MRC/UVRI & LSHTM Uganda Research Unit, P.O. Box 49, Entebbe, Uganda
| | | | - Judith C Aujo
- Department of Paediatrics, Mulago Hospital, P.O. Box 7051, Kampala, Uganda
| | - Gloria Oduru
- MRC/UVRI & LSHTM Uganda Research Unit, P.O. Box 49, Entebbe, Uganda
| | | | - Liam Smeeth
- London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Alison M Elliott
- London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.,MRC/UVRI & LSHTM Uganda Research Unit, P.O. Box 49, Entebbe, Uganda
| | - Emily L Webb
- London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
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Naidoo S, Kagura J, Fabian J, Norris SA. Early Life Factors and Longitudinal Blood Pressure Trajectories Are Associated With Elevated Blood Pressure in Early Adulthood. Hypertension 2019; 73:301-309. [DOI: 10.1161/hypertensionaha.118.11992] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Sanushka Naidoo
- From the MRC/Wits Developmental Pathways for Health Research Unit, Department of Paediatrics and Child Health (S.N., J.K., S.A.N.), University of the Witwatersrand, Johannesburg, South Africa
| | - Juliana Kagura
- From the MRC/Wits Developmental Pathways for Health Research Unit, Department of Paediatrics and Child Health (S.N., J.K., S.A.N.), University of the Witwatersrand, Johannesburg, South Africa
- School of Public Health (J.K.), University of the Witwatersrand, Johannesburg, South Africa
| | - June Fabian
- Wits Donald Gordon Medical Centre (J.F.), University of the Witwatersrand, Johannesburg, South Africa
- Division of Nephrology, Department of Internal Medicine, School of Clinical Medicine (J.F.), University of the Witwatersrand, Johannesburg, South Africa
| | - Shane A. Norris
- From the MRC/Wits Developmental Pathways for Health Research Unit, Department of Paediatrics and Child Health (S.N., J.K., S.A.N.), University of the Witwatersrand, Johannesburg, South Africa
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Munthali RJ, Manyema M, Said-Mohamed R, Kagura J, Tollman S, Kahn K, Gómez-Olivé FX, Micklesfield LK, Dunger D, Norris SA. Body composition and physical activity as mediators in the relationship between socioeconomic status and blood pressure in young South African women: a structural equation model analysis. BMJ Open 2018; 8:e023404. [PMID: 30573484 PMCID: PMC6303607 DOI: 10.1136/bmjopen-2018-023404] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 11/08/2018] [Accepted: 11/09/2018] [Indexed: 01/08/2023] Open
Abstract
OBJECTIVES Varying hypertension prevalence across different socioeconomic strata within a population has been well reported. However, the causal factors and pathways across different settings are less clear, especially in sub-Saharan Africa. Therefore, this study aimed to compare blood pressure (BP) levels and investigate the extent to which socioeconomic status (SES) is associated with BP, in rural and urban South Africa women. SETTING Rural and urban South Africa. DESIGN Cross-sectional. PARTICIPANTS Cross-sectional data on SES, total moderate and vigorous physical activity (MVPA), anthropometric and BP were collected on rural (n=509) and urban (n=510) young black women (18-23 years age). Pregnant and mentally or physically disabled women were excluded from the study. RESULTS The prevalence of combined overweight and obesity (46.5% vs 38.8%) and elevated BP (27.0% vs 9.3%) was higher in urban than rural women, respectively. Results from the structural equation modelling showed significant direct positive effects of body mass index (BMI) on systolic BP (SBP) in rural, urban and pooled datasets. Negative direct effects of SES on SBP and positive total effects of SES on SBP were observed in the rural and pooled datasets, respectively. In rural young women, SES had direct positive effects on BMI and was negatively associated with MVPA in urban and pooled analyses. BMI mediated the positive total effects association between SES and SBP in pooled analyses (ß 0.46; 95% CI 0.15 to 0.76). CONCLUSIONS Though South Africa is undergoing nutritional and epidemiological transitions, the prevalence of elevated BP still varies between rural and urban young women. The association between SES and SBP varies considerably in economically diverse populations with BMI being the most significant mediator. There is a need to tailor prevention strategies to take into account optimising BMI when designing strategies to reduce future risk of hypertension in young women.
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Affiliation(s)
- Richard J Munthali
- MRC/Wits Developmental Pathways for Health Research Unit, Department of Paediatrics, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Mercy Manyema
- MRC/Wits Developmental Pathways for Health Research Unit, Department of Paediatrics, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- DST-NRF Centre of Excellence in Human Development, University of the Witwatersrand, Johannesburg, South Africa
| | - Rihlat Said-Mohamed
- MRC/Wits Developmental Pathways for Health Research Unit, Department of Paediatrics, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Juliana Kagura
- MRC/Wits Developmental Pathways for Health Research Unit, Department of Paediatrics, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Division of Epidemiology and Biostatistics, School of Public Health, University of the Witwatersrand, Johannesburg, South Africa
| | - Stephen Tollman
- MRC/Wits Rural Public Health and Health Transitions Research Unit, School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- INDEPTH Network, Accra, Ghana
- Umeå Centre for Global Health Research, Umeå, Sweden
| | - Kathleen Kahn
- MRC/Wits Rural Public Health and Health Transitions Research Unit, School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- INDEPTH Network, Accra, Ghana
- Umeå Centre for Global Health Research, Umeå, Sweden
| | - F Xavier Gómez-Olivé
- MRC/Wits Rural Public Health and Health Transitions Research Unit, School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Lisa K Micklesfield
- MRC/Wits Developmental Pathways for Health Research Unit, Department of Paediatrics, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - David Dunger
- MRC/Wits Developmental Pathways for Health Research Unit, Department of Paediatrics, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Department of Paediatrics, MRL Wellcome Trust-MRC Institute of Metabolic Science, NIHR Cambridge Comprehensive Biomedical Research Centre, University of Cambridge, Cambridge, UK
| | - Shane A Norris
- MRC/Wits Developmental Pathways for Health Research Unit, Department of Paediatrics, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
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High prevalence of echocardiographic abnormalities in older HIV-infected children taking antiretroviral therapy. AIDS 2018; 32:2739-2748. [PMID: 30289814 PMCID: PMC6250247 DOI: 10.1097/qad.0000000000002031] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Background: Antiretroviral therapy (ART) has decreased mortality so that increasing numbers of children with HIV are reaching adolescence. However, longstanding HIV infection and/or its treatment in children is associated with noninfectious complications including cardiac disease. We investigated the prevalence, spectrum and risk factors for echocardiographic abnormalities among children established on ART. Methods: HIV-infected children aged 6–16 years, on ART at least 6 months were enrolled into a cross-sectional study from a public-sector paediatric HIV clinic in Harare, Zimbabwe. A standardized examination including transthoracic echocardiography was performed. Local echocardiographic reference ranges were used to define cardiac abnormalities. Logistic regression was used to examine the association between cardiac abnormalities and risk factors. Results: Of the 201participants recruited, 92 (46%) were girls and median age was 11 (IQR 9–12) years; CD4+ cell count was 727 cells/μl (IQR 473–935) and 154 (78%) had viral load less than 400 copies/ml. Echocardiographic abnormalities were found in 83 (42%); left ventricular (LV) diastolic dysfunction was the most common abnormality 45 (23%) and LV hypertrophy in 22 (11%). LV and left atrial dilatation were found in 9 (5%) and 16 (8%), respectively. Right ventricular dilatation and systolic dysfunction were found in 13 (7%) and 4 (2%), respectively, of whom 60% had concurrent left heart abnormalities. Current use of nevirapine was associated with LVH [aOR 3.14 (1.13–8.72; P = 0.03)] and hypertension was associated with LV diastolic dysfunction [aOR 3.12 (1.48–6.57; P < 0.01)]. Conclusion: HIV-infected children established on ART have a high burden of echocardiographic abnormalities. Right heart disease was predominantly associated with left heart abnormalities and may be part of a global cardiomyopathic process. Further studies are needed to investigate the natural history, aetiology, and pathogenesis of these abnormalities, so that appropriate monitoring and treatment strategies can be developed.
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Manyema M, Norris SA, Richter LM. Stress begets stress: the association of adverse childhood experiences with psychological distress in the presence of adult life stress. BMC Public Health 2018; 18:835. [PMID: 29976168 PMCID: PMC6034311 DOI: 10.1186/s12889-018-5767-0] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 06/26/2018] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Adverse childhood experiences (ACES) have been linked to poor health and well-being outcomes, including poor mental health such as psychological distress. Both ACEs and psychological distress pose a significant public health burden, particularly in low to middle income countries. Contemporaneous stress events in adulthood may also impact psychological distress. The aims of this study were to describe the prevalence of ACEs and psychological distress and to assess the separate and cumulative effect of ACEs on psychological distress, while accounting for the effect of adult stress. METHODS In this cross-sectional study, we used retrospectively measured ACEs from a sample of 1223 young adults aged between 22 and 23 years (52% female) from the Birth to Twenty Plus Study. Psychological distress and adult life stress were measured with a six-month recall period. Hierarchical logistic regression was employed to assess the associations between the exposures and outcome. RESULTS Nearly 90% of the sample reported at least one ACE and 28% reported psychological distress. The median number of ACEs reported was three (range 0-11). After accounting for demographic and socio-economic factors, all ACEs were individually associated with psychological distress except for parental divorce and unemployment. The individual ACEs increased the odds of PD by between 1.42 and 2.79 times. Compared to participants experiencing no ACEs, those experiencing one to five ACEs were three times more likely to report psychological distress (AOR 3.2 95% CI: 1.83-5.63), while participants who experienced six or more ACEs had nearly eight times greater odds of reporting psychological distress (AOR 7.98 95% CI: 4.28-14.91). Interaction analysis showed that in the absence of adult life stress, the effect of low ACEs compared to high ACEs on PD was not significantly different. DISCUSSION AND CONCLUSION The prevalence of ACEs in this young adult population is high, similar to other studies in young adult populations. A significant direct association exists between ACEs and psychological distress. Adult life stress seems to be a mediator of this relationship. Interventions targeted at psychological distress should address both early life adversity and contemporary stress.
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Affiliation(s)
- Mercy Manyema
- DST-NRF Center of Excellence in Human Development, University of the Witwatersrand, 1st Floor School of Public Health Building, Wits Education Campus, 7 York Road, Parktown, Johannesburg, 2193 South Africa
- MRC/Wits Developmental Pathways for Health Research Unit, Corner College & Clinic Road, Chris Hani Baragwanath Academic Hospital, University of the Witwatersrand, Johannesburg, South Africa
| | - Shane A. Norris
- MRC/Wits Developmental Pathways for Health Research Unit, Corner College & Clinic Road, Chris Hani Baragwanath Academic Hospital, University of the Witwatersrand, Johannesburg, South Africa
| | - Linda M. Richter
- DST-NRF Center of Excellence in Human Development, University of the Witwatersrand, 1st Floor School of Public Health Building, Wits Education Campus, 7 York Road, Parktown, Johannesburg, 2193 South Africa
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Gerber M, Müller I, Walter C, du Randt R, Adams L, Gall S, Joubert N, Nqweniso S, Smith D, Steinmann P, Probst-Hensch N, Utzinger J, Pühse U. Physical activity and dual disease burden among South African primary schoolchildren from disadvantaged neighbourhoods. Prev Med 2018; 112:104-110. [PMID: 29626554 DOI: 10.1016/j.ypmed.2018.04.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 03/02/2018] [Accepted: 04/02/2018] [Indexed: 12/21/2022]
Abstract
People from low- and middle-income countries still face challenges stemming from parasitic infections. Additionally, non-communicable diseases (NCDs) and their risk factors are rapidly increasing, which puts South African children at an elevated risk of a dual disease burden, with negative consequences for child development and wellbeing. Contrastingly, regular physical activity (PA) is associated with decreased cardiovascular disease (CVD) risk. Therefore, the objective of this study was to examine whether PA is associated with the double infection-CVD phenotype burden in South African schoolchildren. 801 children (402 boys, 399 girls; mean age 9.5 years) from eight schools from disadvantaged neighbourhoods were included. Data assessment took place between February and March 2015 in Port Elizabeth, South Africa. Children who achieved PA recommendations (physically active on 6-7 days/week for at least 60 min), who were active, but below recommended standards (2-5 physically active days/week), or who were insufficiently active on almost all days (0-1 physically active days/week) were compared with regard to systolic and diastolic blood pressure, body mass index (BMI), percent body fat, and infection with soil-transmitted helminths. Moderate and high self-reported PA levels were associated with lower BMI, lower body fat, and lower risk of being hypertensive. Conversely, children with high self-reported PA were more likely to be infected with soil-transmitted helminths than peers with low PA levels. Promoting PA in disadvantaged areas is worthwhile to prevent NCD later in life, but should be combined with regular anthelminthic treatment to comprehensively improve children's health and wellbeing.
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Affiliation(s)
- Markus Gerber
- Department of Sport, Exercise and Health, University of Basel, Basel, Switzerland; University of Basel, Basel, Switzerland.
| | - Ivan Müller
- Department of Sport, Exercise and Health, University of Basel, Basel, Switzerland; University of Basel, Basel, Switzerland; Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Cheryl Walter
- Department of Human Movement Science, Nelson Mandela University, Port Elizabeth, South Africa
| | - Rosa du Randt
- Department of Human Movement Science, Nelson Mandela University, Port Elizabeth, South Africa
| | - Larissa Adams
- Department of Human Movement Science, Nelson Mandela University, Port Elizabeth, South Africa
| | - Stefanie Gall
- Department of Sport, Exercise and Health, University of Basel, Basel, Switzerland; University of Basel, Basel, Switzerland
| | - Nandi Joubert
- Department of Human Movement Science, Nelson Mandela University, Port Elizabeth, South Africa
| | - Siphesihle Nqweniso
- Department of Human Movement Science, Nelson Mandela University, Port Elizabeth, South Africa
| | - Danielle Smith
- Department of Human Movement Science, Nelson Mandela University, Port Elizabeth, South Africa
| | - Peter Steinmann
- University of Basel, Basel, Switzerland; Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Nicole Probst-Hensch
- University of Basel, Basel, Switzerland; Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Jürg Utzinger
- University of Basel, Basel, Switzerland; Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Uwe Pühse
- Department of Sport, Exercise and Health, University of Basel, Basel, Switzerland; University of Basel, Basel, Switzerland
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Lu X, Xu X, Lin Y, Zhang Y, Huo X. Phthalate exposure as a risk factor for hypertension. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:20550-20561. [PMID: 29862479 DOI: 10.1007/s11356-018-2367-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 05/22/2018] [Indexed: 02/05/2023]
Abstract
Phthalates are ubiquitous in environment. Hypertension is a major risk factor for cardiovascular diseases. Phthalate exposure is associated with hypertension in multiple studies. This review aims to summarize the scientific literature on associations between phthalate exposure and hypertension and discuss the mechanisms in the relationship. We identified and reviewed original articles published to March 2018, using PubMed and Web of Science to search the terms "phthalate(s)," "phthalic acid," "blood pressure," "high blood pressure," "hypertension," "prehypertension," and "cardiovascular disease." Findings were summarized based on the relevance to the themes, including presentation of main phthalates and their major metabolites as well as associations of phthalate exposure with blood pressure in epidemiological and experimental studies. We identified ten population-based investigations and five toxicological experiments. Epidemiological data underscored a possible correlation between phthalate exposure and hypertension in adults, whereas individual study in children stands on the opposite. Experimental studies mainly targeted the increasing effect of phthalates on blood pressure. This review suggested some underlying mechanisms of phthalate-associated hypertension. Considering the current evidence, phthalate might be risk factors of hypertension. However, the effect of phthalate exposure in early life on blood pressure in later life or adulthood is still unclear. Well-designed longitudinal and molecular mechanism studies are indispensable.
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Affiliation(s)
- Xueling Lu
- Laboratory of Environmental Medicine and Developmental Toxicology and Guangdong Provincial Key Laboratory of Infectious Diseases, Shantou University Medical College, Shantou, 515041, Guangdong, China
| | - Xijin Xu
- Laboratory of Environmental Medicine and Developmental Toxicology and Guangdong Provincial Key Laboratory of Infectious Diseases, Shantou University Medical College, Shantou, 515041, Guangdong, China
- Department of Cell Biology and Genetics, Shantou University Medical College, Shantou, 515041, Guangdong, China
| | - Yucong Lin
- Tabor Academy, Marion, MA, USA
- Laboratory of Environmental Medicine and Developmental Toxicology, Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou, 511486, Guangdong, China
| | - Yu Zhang
- Laboratory of Environmental Medicine and Developmental Toxicology and Guangdong Provincial Key Laboratory of Infectious Diseases, Shantou University Medical College, Shantou, 515041, Guangdong, China
- Department of Pathology and Medical Biology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Xia Huo
- Laboratory of Environmental Medicine and Developmental Toxicology and Guangdong Provincial Key Laboratory of Infectious Diseases, Shantou University Medical College, Shantou, 515041, Guangdong, China.
- Laboratory of Environmental Medicine and Developmental Toxicology, Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou, 511486, Guangdong, China.
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Zhang R, Li C, Liu T, Zheng L, Li S. Handgrip Strength and Blood Pressure in Children and Adolescents: Evidence From NHANES 2011 to 2014. Am J Hypertens 2018; 31:792-796. [PMID: 29529209 PMCID: PMC5998948 DOI: 10.1093/ajh/hpy032] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 02/20/2018] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND Previous studies have reported that handgrip strength, a measure of muscular fitness, is associated with cardiovascular risk factors. However, the association of handgrip strength with blood pressure (BP) in children has been inconsistent. We tested the association of handgrip strength with systolic and diastolic BP in children and adolescents from the National Health and Nutrition Examination Survey (NHANES) 2011-2014. METHODS The study included 3,929 participants aged 8-19 years who underwent a handgrip test. The sum of the maximum handgrip strength from both hands was used. General linear models were used to examine the associations between handgrip strength and the outcome variables. RESULTS After adjustment for age, race, sex, body mass index, and physical activities, handgrip strength was significantly and positively associated with systolic (P < 0.0001) and diastolic (P = 0.01) BP. There was an increasing trend in systolic BP as handgrip strength increased from the bottom quartile to the top quartile, with 2.1 mm Hg difference between the top and the bottom quartiles (P for trend <0.0001). Similar results were observed for diastolic BP. CONCLUSIONS Muscular fitness is positively associated with BP in children and adolescents. The implications and underlying mechanisms for these results need further examinations.
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Affiliation(s)
- Rui Zhang
- Institute of Chronic Disease Surveillance, Liaoning Provincial Center for Disease Control and Prevention, Shenyang, China,Department of Epidemiology, Tulane School of Public Health and Tropical Medicine, New Orleans, Louisiana, USA
| | - Changwei Li
- Department of Epidemiology and Biostatistics, University of Georgia College of Public Health, Athens, Georgia, USA
| | - Tingting Liu
- Department of Epidemiology, Tulane School of Public Health and Tropical Medicine, New Orleans, Louisiana, USA,Eleanor Mann School of Nursing, University of Arkansas College of Education and Health Professions, Fayetteville, Arkansas, USA
| | - Liqiang Zheng
- Department of Clinical Epidemiology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Shengxu Li
- Department of Epidemiology, Tulane School of Public Health and Tropical Medicine, New Orleans, Louisiana, USA,Correspondence: Shengxu Li ()
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Is birth weight associated with blood pressure among African children and adolescents? A systematic review. J Dev Orig Health Dis 2018; 9:270-280. [PMID: 29353561 DOI: 10.1017/s2040174417001039] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
There is substantial evidence of an inverse association between birth weight and later blood pressure (BP) in populations from high-income countries, but whether this applies in low-income countries, where causes of low birth weight are different, is not certain. OBJECTIVE We conducted a review of the evidence on the relationship between birth weight and BP among African children and adolescents. Medline, EMBASE, Global Health and Web of Science databases were searched for publications to October 2016. Papers reporting the relationship between birth weight and BP among African children and adolescents were assessed. Bibliographies were searched for further relevant publications. Selected papers were summarized following the preferred reporting items for systematic review and meta-analysis (PRISMA) guidelines. In total, 16 papers from 13 studies conducted in nine African countries (Nigeria, Republic of Seychelles, Gambia, Democratic Republic of Congo, Cameroon, South Africa, Algeria, Zimbabwe and Angola) were reviewed. Eight studies were cohorts, while five were cross-sectional. The relationship between birth weight and later BP varied with age of the participants. Studies in neonates showed a consistently positive association, while predominantly inverse associations were seen among children, and studies in adolescents were inconsistent. Based on the limited number of studies identified, the relationship between birth weight and later BP may vary with age in African children and adolescents. Not all studies adequately controlled for confounding, notably gender or age. Whether the inverse relationship between birth weight and BP in later life observed in Western settings is also seen in Africa remains unclear.
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Hendry LM, Sahibdeen V, Choudhury A, Norris SA, Ramsay M, Lombard Z. Insights into the genetics of blood pressure in black South African individuals: the Birth to Twenty cohort. BMC Med Genomics 2018; 11:2. [PMID: 29343252 PMCID: PMC5773038 DOI: 10.1186/s12920-018-0321-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 01/03/2018] [Indexed: 02/08/2023] Open
Abstract
Background Cardiovascular diseases (CVDs) are the leading cause of non-communicable disease deaths globally, with hypertension being a major risk factor contributing to CVDs. Blood pressure is a heritable trait, with relatively few genetic studies having been performed in Africans. This study aimed to identify genetic variants associated with variance in systolic (SBP) and diastolic (DBP) blood pressure in black South Africans. Methods Genotyping was performed using the Metabochip in a subset of participants (mixed sex; median age 17.9) and their adult female caregivers (median age 41.0) from the Birth to Twenty cohort (n = 1947). Data were analysed as a merged dataset (all participants and caregivers together) in GEMMA (v0.94.1) using univariate linear mixed models, incorporating a centered relatedness matrix to account for the relatedness between individuals and with adjustments for age, sex, BMI and principal components of the genotype information. Results Association analysis identified regions of interest in the NOS1AP (DBP: rs112468105 - p = 7.18 × 10−5 and SBP: rs4657181 - p = 4.04 × 10−5), MYRF (SBP: rs11230796 - p = 2.16 × 10−7, rs400075 - p = 2.88 × 10−7) and POC1B (SBP: rs770373 - p = 7.05 × 10−5, rs770374 - p = 9.05 × 10−5) genes and some intergenic regions (DACH1|LOC440145 (DBP: rs17240498 - p = 4.91 × 10−6 and SBP: rs17240498 - p = 2.10 × 10−5) and INTS10|LPL (SBP: rs55830938 - p = 1.30 × 10−5, rs73599609 - p = 5.78 × 10−5, rs73667448 - p = 6.86 × 10−5)). Conclusions The study provided further insight into the contribution of genetic variants to blood pressure in black South Africans. Future functional and replication studies in larger samples are required to confirm the role of the identified loci in blood pressure regulation and whether or not these variants are African-specific. Electronic supplementary material The online version of this article (10.1186/s12920-018-0321-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Liesl M Hendry
- School of Molecular & Cell Biology, Faculty of Science, University of the Witwatersrand, Johannesburg, South Africa. .,Sydney Brenner Institute for Molecular Bioscience, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
| | - Venesa Sahibdeen
- Division of Human Genetics, School of Pathology, Faculty of Health Sciences, National Health Laboratory Service & University of the Witwatersrand, Johannesburg, South Africa
| | - Ananyo Choudhury
- Sydney Brenner Institute for Molecular Bioscience, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Shane A Norris
- MRC/Wits Developmental Pathways for Health Research Unit, Department of Paediatrics, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Michèle Ramsay
- Sydney Brenner Institute for Molecular Bioscience, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.,Division of Human Genetics, School of Pathology, Faculty of Health Sciences, National Health Laboratory Service & University of the Witwatersrand, Johannesburg, South Africa
| | - Zané Lombard
- School of Molecular & Cell Biology, Faculty of Science, University of the Witwatersrand, Johannesburg, South Africa.,Division of Human Genetics, School of Pathology, Faculty of Health Sciences, National Health Laboratory Service & University of the Witwatersrand, Johannesburg, South Africa
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Prevalence of elevated blood pressure in children and adolescents in Africa: a systematic review and meta-analysis. LANCET PUBLIC HEALTH 2017; 2:e375-e386. [PMID: 29253478 DOI: 10.1016/s2468-2667(17)30123-8] [Citation(s) in RCA: 103] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 06/04/2017] [Accepted: 06/09/2017] [Indexed: 12/15/2022]
Abstract
BACKGROUND Despite substantial attention paid to the threat of elevated blood pressure in children and adolescents in high-income countries and the epidemic of hypertension in African adult populations, data on the burden of elevated blood pressure in African children and adolescents have not yet been synthesised. We did a systematic review and meta-analysis to provide estimates of the prevalence of elevated blood pressure and assess associated factors among children and adolescents in Africa. METHODS We searched Embase, PubMed, African Journals Online, and African Index Medicus to identify articles published from Jan 1, 1996, to Feb 2, 2017, and searched the reference list of retrieved articles. Each study was independently reviewed for methodological quality. We used a random-effects model to estimate the prevalence of elevated blood pressure across studies and heterogeneity (I2) was assessed via the χ2 test on Cochran's Q statistic. This review is registered with PROSPERO, number CRD42015019029. FINDINGS We included 51 studies in qualitative synthesis and 25 in the meta-analysis reporting data of a pooled sample of 54 196 participants aged 2-19 years. Study quality was high with only four medium-quality studies and no low-quality studies. Prevalence of elevated blood pressure varied widely across studies (range 0·2-24·8%). The pooled prevalence of elevated blood pressure (systolic or diastolic blood pressure ≥95th percentile) was 5·5% (95% CI 4·2-6·9), whereas that of slightly elevated blood pressure (systolic or diastolic blood pressure ≥90th percentile and <95th percentile) was 12·7% (2·1-30·4). The prevalence of elevated blood pressure was largely associated with body-mass index (BMI), with a prevalence of elevated blood pressure six times higher in obese (30·8%, 95% CI 20·1-42·6) versus normal-weight children (5·5%, 3·1-8·4; p<0·0001). INTERPRETATION This study suggests a high prevalence of elevated blood pressure among children and adolescents in Africa, with overweight and obesity being an important risk factor. Efforts to address this burden of elevated blood pressure in children and adolescents should mainly focus on primary prevention at the community level, by promoting healthy lifestyles and avoiding other cardiovascular risk factors, especially overweight and obesity. This study also stresses the need for more elaborate studies using uniform and reliable diagnostic methods to reliably map the burden of elevated blood pressure in children and adolescents in Africa. FUNDING None.
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Martinovic M, Belojevic G, Evans GW, Kavaric N, Asanin B, Pantovic S, Jaksic M, Boljevic J. Hypertension and correlates among Montenegrin schoolchildren-a cross-sectional study. Public Health 2017; 147:15-19. [PMID: 28404491 DOI: 10.1016/j.puhe.2017.02.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2016] [Revised: 02/01/2017] [Accepted: 02/06/2017] [Indexed: 12/28/2022]
Abstract
OBJECTIVES In one of the few national studies of children in a former Eastern bloc country emerging as a Western democracy and the first such study ever in Montenegro, this study establishes the prevalence and correlates of childhood hypertension (CH). STUDY DESIGN A cross-sectional national study. METHODS The study was conducted with 3254 children aged 7-13 years (50.3% male) from 39 elementary schools. We used a structured questionnaire to gather sociodemographic information as well as data on factors potentially related to CH. Children's nutritional status was assessed using the criteria of the International Obesity Task Force. Waist circumference was also measured. Blood pressure was measured in schools using an oscillometric monitor. CH was defined as an average systolic blood pressure and/or diastolic blood pressure greater than or equal to the 95th percentile for sex, age, and height. RESULTS The prevalence of CH was 10.4% with no differences between boys and girls. Multiple regression revealed that the odds for child hypertension were lowered by 10% for each year of age. On the other hand, rural environment and child obesity raised the odds of hypertension by 38% and 68%, respectively. CONCLUSIONS We found hypertension in one out of ten Montenegrin schoolchildren, with no gender differences. Obesity and rural areas may be unfriendly to children's blood pressure.
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Affiliation(s)
- M Martinovic
- Medical Faculty, Department for Pathophysiology and Laboratory Medicine, University of Montenegro, Podgorica, Montenegro.
| | - G Belojevic
- Faculty of Medicine, Institute of Hygiene and Medical Ecology, University of Belgrade, Belgrade, Serbia.
| | - G W Evans
- Department of Design and Environmental Analysis, Bronfenbrenner Center for Translational Research, Cornell University, Ithaca, NY, USA; Department of Human Development, Bronfenbrenner Center for Translational Research, Cornell University, Ithaca, NY, USA.
| | - N Kavaric
- Public Health Center, Podgorica, Montenegro.
| | - B Asanin
- Medical Faculty, Neurosurgery Clinic, University of Montenegro, Podgorica, Montenegro.
| | - S Pantovic
- Medical Faculty, Department of Biochemistry, University of Montenegro, Podgorica, Montenegro.
| | - M Jaksic
- Clinical Centre of Montenegro, Centre for Laboratory Diagnostics, Podgorica, Montenegro.
| | - J Boljevic
- Clinical Centre of Montenegro, Centre for Laboratory Diagnostics, Podgorica, Montenegro.
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Jobe M, Agbla SC, Prentice AM, Hennig BJ. High blood pressure and associated risk factors as indicator of preclinical hypertension in rural West Africa: A focus on children and adolescents in The Gambia. Medicine (Baltimore) 2017; 96:e6170. [PMID: 28353557 PMCID: PMC5380241 DOI: 10.1097/md.0000000000006170] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Hypertension is fast becoming a major public health problem across sub-Saharan Africa. We sought to determine the prevalence of high blood pressure (BP) and associated risk factors as indicator of preclinical hypertension in a rural Gambian population.We analyzed data on 6160 healthy Gambians cross-sectionally. Attention was given to 5 to <18-year olds (N = 3637), as data from sub-Saharan Africa on this young age group are scarce. High BP was defined as systolic blood pressure (SBP) above the 95th percentile for age-sex specific height z scores in <18-year olds employing population-specific reference values. Standard high BP categories were applied to ≥18-year olds.In <18-year olds, the multivariable analysis gave an adjusted high BP prevalence ratio of 0.95 (95% confidence interval [CI] 0.92-0.98; P = 0.002) for age and 1.13 (95% CI 1.06-1.19; P < 0.0001) for weight-for-height z score (zWT-HT); sex and hemoglobin were not shown to affect high BP. In adults age 1.05 (95% CI 1.04-1.05; P < 0.0001), body mass index z score 1.28 (95% CI 1.16-1.40; P < 0.0001), hemoglobin 0.90 (95% CI 0.85-0.96; P < 0.0001) and high fasting glucose 2.60 (95% CI 2.02-3.36; P < 0.0001, though the number was very low) were confirmed as risk factors for high BP prevalence; sex was not associated.The reported high BP prevalence and associated risk factors in adults are comparable to other studies conducted in the region. The observed high BP prevalence of 8.2% (95% CI 7.4-9.2) in our generally lean young Gambians (<18 years) is alarming, given that high BP tracks from childhood to adulthood. Hence there is an urgent need for further investigation into risk factors of pediatric high BP/hypertension even in rural African settings.
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Affiliation(s)
- Modou Jobe
- Nutrition Theme, MRC Unit The Gambia, Atlantic Boulevard, Fajara, Banjul, The Gambia
| | - Schadrac C. Agbla
- Tropical Epidemiology Group, Faculty of Epidemiology and Population Health
| | - Andrew M. Prentice
- Nutrition Theme, MRC Unit The Gambia, Atlantic Boulevard, Fajara, Banjul, The Gambia
- MRC International Nutrition Group, Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, Keppel Street, London, UK.
| | - Branwen J. Hennig
- Nutrition Theme, MRC Unit The Gambia, Atlantic Boulevard, Fajara, Banjul, The Gambia
- MRC International Nutrition Group, Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, Keppel Street, London, UK.
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Kagura J, Adair LS, Munthali RJ, Pettifor JM, Norris SA. Association Between Early Life Growth and Blood Pressure Trajectories in Black South African Children. Hypertension 2016; 68:1123-1131. [PMID: 27672027 DOI: 10.1161/hypertensionaha.116.08046] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 08/23/2016] [Indexed: 11/16/2022]
Abstract
Early growth is associated with blood pressure measured on one occasion, but whether early life growth patterns are associated with longitudinal blood pressure trajectories is under-researched. Therefore, we sought to examine the association between early growth and blood pressure trajectories from childhood to adulthood. Blood pressure was measured on 7 occasions between ages 5 and 18 years in the Birth to Twenty cohort study, and conditional variables for growth in infancy and mid-childhood were computed from anthropometric measures (n=1937, 52% girls). We used a group-based trajectory modeling approach to identify distinct height-adjusted blood pressure trajectories and then tested their association with growth between birth and mid-childhood adjusting for several covariates. Three trajectory groups were identified for systolic and diastolic blood pressure: lower, middle, and upper in boys and girls, separately. In boys, predictors of the middle or upper systolic blood pressure trajectories versus the lower trajectory were in birth weight (odds ratio 0.75 [95% confidence interval 0.58-0.96] per SD) and relative weight gain in infancy (4.11 [1.25-13.51] per SD). In girls, greater relative weight gain and linear growth in both infancy and mid-childhood were consistently associated with an almost 2-fold higher likelihood of being in the upper versus lower systolic blood pressure trajectory. The associations for the diastolic blood pressure trajectories were inconsistent. These findings emphasize the importance of identifying children at risk of progression to high blood pressure. Accelerated growth in infancy and mid-childhood may be a key target for early life intervention in prevention of elevated blood pressure progression.
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Affiliation(s)
- Juliana Kagura
- From the MRC/Wits Developmental Pathways for Health Research Unit, Department of Paediatrics and Child Health, University of the Witwatersrand, Johannesburg, South Africa (J.K., L.S.A., R.J.M., J.M.P., S.A.N.); and Department of Nutrition, University of North Carolina, Chapel Hill (L.S.A.).
| | - Linda S Adair
- From the MRC/Wits Developmental Pathways for Health Research Unit, Department of Paediatrics and Child Health, University of the Witwatersrand, Johannesburg, South Africa (J.K., L.S.A., R.J.M., J.M.P., S.A.N.); and Department of Nutrition, University of North Carolina, Chapel Hill (L.S.A.)
| | - Richard J Munthali
- From the MRC/Wits Developmental Pathways for Health Research Unit, Department of Paediatrics and Child Health, University of the Witwatersrand, Johannesburg, South Africa (J.K., L.S.A., R.J.M., J.M.P., S.A.N.); and Department of Nutrition, University of North Carolina, Chapel Hill (L.S.A.)
| | - John M Pettifor
- From the MRC/Wits Developmental Pathways for Health Research Unit, Department of Paediatrics and Child Health, University of the Witwatersrand, Johannesburg, South Africa (J.K., L.S.A., R.J.M., J.M.P., S.A.N.); and Department of Nutrition, University of North Carolina, Chapel Hill (L.S.A.)
| | - Shane A Norris
- From the MRC/Wits Developmental Pathways for Health Research Unit, Department of Paediatrics and Child Health, University of the Witwatersrand, Johannesburg, South Africa (J.K., L.S.A., R.J.M., J.M.P., S.A.N.); and Department of Nutrition, University of North Carolina, Chapel Hill (L.S.A.)
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Omega-3 polyunsaturated fatty acid supplementation during the pre and post-natal period: A meta-analysis and systematic review of randomized and semi-randomized controlled trials. JOURNAL OF NUTRITION & INTERMEDIARY METABOLISM 2016. [DOI: 10.1016/j.jnim.2016.04.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Munthali RJ, Kagura J, Lombard Z, Norris SA. Childhood adiposity trajectories are associated with late adolescent blood pressure: birth to twenty cohort. BMC Public Health 2016; 16:665. [PMID: 27473865 PMCID: PMC4966706 DOI: 10.1186/s12889-016-3337-x] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Accepted: 07/21/2016] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Elevated blood pressure in childhood is a risk factor for adult hypertension which is a global health problem. Excess adiposity in childhood creates a predisposition to develop adult hypertension. Our aim was to explore distinct sex-specific adiposity trajectories from childhood to late adolescence and examined their association with blood pressure. METHODS Latent Class Growth Mixture Modeling (LCGMM) on longitudinal data was used to derive sex-specific and distinct body mass index (BMI: kg/m(2)) trajectories. We studied 1824 black children (boys = 877, girls = 947) from the Birth to Twenty (Bt20) cohort from Soweto, South Africa, and obtained BMI measures at ages 5 through 18 years. Participants with at least two age-point BMI measures, were included in the analysis. Analysis of variance (ANOVA), chi-square test, multivariate linear and standard logistic regressions were used to test study characteristics and different associations. RESULTS We identified three (3) and four (4) distinct BMI trajectories in boys and girls, respectively. The overall prevalence of elevated blood pressure (BP) was 34.9 % (39.4 % in boys and 30.38 % in girls). Boys and girls in the early onset obesity or overweight BMI trajectories were more likely to have higher BP values in late adolescence. Compared to those in the normal weight BMI trajectory, girls in early onset obesity trajectories had an increased risk of elevated BP with odds ratio (OR) of 2.18 (95 % confidence interval 1.31 to 4.20) and 1.95 (1.01 to 3.77). We also observed the weak association for boys in early onset overweight trajectory, (p-value = 0.18 and odds ratio of 2.39 (0.67 to 8.57)) CONCLUSIONS: Distinct weight trajectories are observed in black South African children from as early as 5 years. Early onset adiposity trajectories are associated with elevated BP in both boys and girls. It is important to consider individual patterns of early-life BMI development, so that intervention strategies can be targeted to at-risk individuals.
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Affiliation(s)
- Richard J. Munthali
- School of Molecular and Cell Biology, Faculty of Science, University of the Witwatersrand, The Mount, 9 Jubilee Road, Parktown, Johannesburg, 2193 South Africa
- Sydney Brenner Institute for Molecular Biosciences (SBIMB), University of the Witwatersrand, Johannesburg, South Africa
- MRC/Wits Developmental Pathways for Health Research Unit (DPHRU), University of the Witwatersrand, Johannesburg, South Africa
- Division of Human Genetics, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand and National Health Laboratory Service, Johannesburg, South Africa
| | - Juliana Kagura
- MRC/Wits Developmental Pathways for Health Research Unit (DPHRU), University of the Witwatersrand, Johannesburg, South Africa
| | - Zané Lombard
- School of Molecular and Cell Biology, Faculty of Science, University of the Witwatersrand, The Mount, 9 Jubilee Road, Parktown, Johannesburg, 2193 South Africa
- Division of Human Genetics, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand and National Health Laboratory Service, Johannesburg, South Africa
| | - Shane A. Norris
- MRC/Wits Developmental Pathways for Health Research Unit (DPHRU), University of the Witwatersrand, Johannesburg, South Africa
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