Impact of urbanisation and altitude on the incidence of, and risk factors for, hypertension

Hypertension subtypes at high altitude in Peru: Analysis of the Demographic and Family Health Survey 2016-2019

BACKGROUND

The prevalence of hypertension in Peru has increased over the years. Approximately one third of the Peruvian population lives at high altitudes. This population presents particular physiological, genetic and environmental characteristics that could be related to the prevalence of hypertension and its subtypes.

OBJECTIVE

To assess the association between altitude and hypertension in the Peruvian population through an analysis of a nationally representative survey.

METHODS

We conducted a cross-sectional analysis of the Demographic and Family Health Survey for the period 2016-2019. We included 122,336 individuals aged 18 years and older. Hypertension was defined according to the JNC-7 guidelines. High-altitude location was defined as a residential cluster located above 2,500 meters above sea level. We utilized generalized linear models from the Poisson family with a log-link function to assess the magnitude of the association between high altitude and hypertension. Additionally, we employed multinomial regression models to analyze the association between high altitude and subtypes of hypertension, including isolated systolic hypertension (ISH), isolated diastolic hypertension (IDH), and systolic-diastolic hypertension (SDH).

RESULTS

In the adjusted Poisson regression model, we found that the prevalence of hypertension among participants living at high altitudes was lower compared to those living at low altitudes (aPR: 0.89; 95% CI: 0.86-0.93). In the adjusted multinomial regression model, we observed a lower prevalence rate of ISH among participants residing at high altitudes (aRPR: 0.68; 95% CI: 0.61-0.73) and a higher prevalence rate of IDH among participants residing at high altitudes (aRPR: 1.60; 95% CI: 1.32-1.94).

CONCLUSIONS

Residents at high altitudes in Peru have a lower prevalence rate of ISH and a higher prevalence rate of IDH compared to those living at low altitudes. Further studies are needed to determine the influence of other biological, environmental, and healthcare access factors on this relationship.

Multimorbidity and acute infectious diseases in urban and semi-urban settings in Peru: A mixed-methods study

Background

The co-occurrence of chronic diseases and acute infectious events exacerbates disability and diminishes quality of life, yet research in Low- and Middle-Income countries is scarce. We aimed to investigate the relationship between infectious events and multimorbidity in resource-constrained settings.

Methods

We conducted a sequential mixed-method study in Lima and Tumbes, Peru, with participants having multimorbidity from the CRONICAS Cohort Study. They completed a questionnaire on the occurrence, treatment, and health-seeking behaviour related to acute infectious events. Qualitative interviews explored the perceptions and links between multimorbidity and acute infectious events for a subgroup of participants.

Findings

Among individuals with multimorbidity, low awareness of chronic conditions and poor medication adherence. The cumulative incidence for respiratory and gastrointestinal infections, the most reported acute conditions, was 2.0 [95%CI: 1.8-2.2] and 1.6 [1.2-1.9] events per person per year, respectively. Individuals with cancer (6.4 [1.6-11.2] events per person per year) or gastrointestinal reflux (7.2 [4.4-10.1] events per person per year) reported higher cumulative incidence of infectious events than others, such as those with cardiovascular and metabolic conditions (5.2 [4.6-5.8] events per person per year). Those with three or more chronic conditions had a slightly higher cumulative incidence compared with individuals with two conditions (5.7 [4.4-7.0] vs 5.0 [4.4-5.6] events per person per year). Around 40% of individuals with multimorbidity sought healthcare assistance, while others chose drugstores or didn't seek help. Our qualitative analysis showed diverse perceptions among participants regarding the connections between chronic and acute conditions. Those who recognized a connection emphasized the challenges in managing these interactions.

Interpretation

Our study advances understanding of multimorbidity challenges in resource-limited settings, highlighting the impact of acute infections on patients' existing multimorbidity burden.

Prevalence of hypertension in adults living at altitude in Latin America and the Caribbean: A systematic review and meta-analysis

OBJECTIVE

The objective of this systematic review and meta-analysis was to assess the prevalence of hypertension in populations living at altitude in Latin America and the Caribbean.

METHODS

We conducted a systematic search from January 1, 2000 to January 10, 2023 in Web of Science (WoS)/Core Collection, WoS/Medline, WoS/Scielo, Scopus, PubMed and Embase databases. We included studies that assessed the prevalence of hypertension in altitude populations (>1500 m.a.s.l.) and these were meta-analyzed using a random-effects model. To assess the sources of heterogeneity, we performed subgroup and meta-regression analyses.

RESULTS

Thirty cross-sectional studies (117 406 participants) met the inclusion criteria. Studies used different cut-off points. The prevalence of hypertension in the studies that considered the cut-off point of ≥ 140/90 mmHg in the general population was 19.1%, ≥ 130/85 mmHg was 13.1%, and ≥ 130/80 mmHg was 43.4%. There was a tendency for the prevalence of hypertension to be higher in men. In meta-regression analyses, no association was found between altitude, mean age, year of publication, risk of bias and prevalence of hypertension.

CONCLUSION

The prevalence of hypertension in the altitude population of Latin America and the Caribbean is lower than that reported in populations living at sea level and lower than other altitude populations such as Tibetans.

PROSPERO

CRD42021275229.

Implementation of a salt substitute intervention using social marketing in resourced-limited communities in Peru: a process evaluation study

Objective

This study aimed to conduct a process evaluation of a salt substitute trial conducted in Peru.

Methods

Through semi-structured interviews of intervention participants, we documented and analyzed process evaluation variables as defined by the Medical Research Council Framework. This study was a stepped wedge trial conducted in Tumbes, Peru in 2014. The intervention was a community-wide replacement of regular salt (100% sodium) with "Salt Liz" (75% sodium and 25% potassium) using social marketing strategies to promote the adoption and continued use of the salt substitute in daily life. The components of the social marketing campaign included entertainment educational activities and local product promoters ("Amigas de Liz"). Another component of the intervention was the Salt Liz spoon to help guide the amount of salt that families should consume. The process evaluation variables measured were the context, mechanism of action, and implementation outcomes (acceptability, fidelity and adoption, perceptions, and feedback).

Results

In total, 60 women were interviewed, 20 with hypertension and 40 without hypertension. Regarding context, common characteristics across the four villages included residents who primarily ate their meals at home and women who were responsible for household food preparation. As the mechanism of action, most participants did not notice a difference in the flavor between regular salt and Salt Liz; those that did notice a difference took around 2 weeks to become accustomed to the taste of the salt substitute. In terms of implementation outcomes, the Salt Liz was accepted by villagers and factors explaining this acceptability included that it was perceived as a "high quality" salt and as having a positive effect on one's health. Participants recognized that the Salt Liz is healthier than regular salt and that it can help prevent or control hypertension. However, most participants could not accurately recall how the compositions of the Salt Liz and regular salt differed and the role they play in hypertension. Although the use of the Salt Liz was far-reaching at the community level, the use of the Salt Liz spoon was poor. Educational entertainment activities were well-received, and most participants enjoyed them despite not always being active participants but rather sideline observers.

Conclusion

This process evaluation identifies key intervention components that enabled a successful trial. Seeking and incorporating feedback from the target population helps deepen the understanding of contextual factors that influence an intervention's success. Furthermore, feedback received can aid the development of the intervention product. Some factors that can be improved for future interventions are acknowledged.

Clinical trial registration

NCT01960972.

Association between multimorbidity with cognitive dysfunction in a Peruvian population

BACKGROUND

Previous studies have shown that multimorbidity is a risk factor for cognitive dysfunction (CD).Type 2 diabetes mellitus (T2DM) and hypertension (HT) are very common risk factors.The association between multimorbidity due to both diseases and CD has been understudied in low and middle-income countries, in which the strength of the association might be stronger.

AIM

To evaluate the association between multimorbidity due to T2DM and HT with CD among adults ≥50 years in Tumbes.

MATERIALS AND METHODS

A secondary analysis of a population-based cross-sectional study was conducted. The exposure variable was the presence of both T2DM and HT, split into categories: without HT or T2DM, only T2DM, only HT, and with T2DM and HT; whereas CD was the outcome variable, defined as a score ≤26 in the Leganes Cognitive Test. Crude and adjusted generalized linear models were used to estimate the association of interest, and prevalence ratio (PR) and 95% confidence interval (95%CI) were reported.

RESULTS

688 participants were analyzed. The prevalence of CD was 39.1%. There was a 56.1% of participants without TDM2 nor HT, 8.3% with T2DM, 28.9% with HT and 6.7% with both diseases. A significant association was found between multimorbidity and CD (PR = 1.43, 95%CI 1.04-1.97). Multimorbidity had a statistically significant association with CD in the group of participants with ≥7 years of education (PR = 2.56,95%CI 1.55-4.21), but no in the group with <7 years.

CONCLUSIONS

There is association between the morbidity of T2DM and HT, and CD among adults ≥50 years of age in Tumbes. Education was an effect modifier of the association between HT and T2DM on the presence of CD.

Oxidative stress and metabolic parameters in hypertensive patients with/without diabetes mellitus in cardiovascular risk evaluation

Introduction: Hypertension and diabetes mellitus affect a large number of patients and can significantly influence their life expectancy. Changes in metabolic and oxidative stress parameters are common in these pathologies, contributing to associated complications. The aim of the study was assessment of relationship between laboratory parameters and their role in evaluation of cardiovascular risk, and possible gender-related differences in the protective factors.

Material and methods: Blood samples were collected from hypertensive patients with/without diabetes mellitus admitted to the Cardiovascular Rehabilitation Clinic in Tîrgu Mureș and controls without these pathologies. Biochemical analyses were performed on Konelab analyzer (glycemia, lipid profile, kidney function tests, zinc, hsCRP). Oxidative stress markers, such as serum malondialdehyde (MDA), oxidized (GSSG) and reduced glutathione (GSH) were evaluated using an HPLC-UV/VIS technique at GEP UMPhST. Statistical analysis was performed by GraphPad InStat3.

Results: Mean age of hypertensive patients (n=131) was 69.44 ± 9.02 years, 45.8% males, 31.3% being diabetics. 74.1% of the studied patients had zinc deficiency, 19.8% presented slightly elevated hsCRP. The control group included 24 nonhypertensive/nondiabetic patients of similar age. Average GSH was significantly lower (p=0.0002) in hypertensive patients, 1.89 ± 0.82 µg/ml, compared to the control group (3.23 ± 0.49 µg/ml), and no correlation could be observed between GSH and MDA values. GSH concentration was significantly higher in males (p=0.0395) and HDL-cholesterol significantly higher in females (p=0.0132). A negative correlation was observed between serum triglyceride and HDL-cholesterol concentration.

Conclusions: Gender differences are present in the level of protective factors against cardiovascular diseases, while oxidative stress is intensified in hypertensive/diabetic patients.

Trends and geographical variation in mortality from coronary disease in Peru

Background

Coronary disease (CD) is the main cause of mortality worldwide. Data about trends and geographical variation in CD mortality is available in some American countries. This information varies among countries since CD risk factors frequencies vary.

Objective

To describe the trend and geographical variation of coronary disease (CD) mortality in Peru, 2005–2017.

Methods

Analysis of secondary data of the Peruvian Ministry of Health’s registry of deaths. We analyzed CD mortality. We described the absolute and relative frequency of deaths and age-standardized mortality rate (ASMR) by natural regions, departments, age, sex, and year. We also described the change of ASMR between two periods (2005–2010 vs. 2011–2017).

Results

There were 64,721 CD deaths between 2005 and 2017 (4.12% among all deaths). The absolute frequency of CD deaths was 5,665 and 6,565 in 2005 and 2017, respectively. CD mortality was more frequent in men and older adults. The ASMR varied among natural regions, being higher in the Coast (19.61 per 100,000 inhabitants). The change between the two periods revealed that almost all departments reduced their ASMRs, except for Callao, Lambayeque, and Madre de Dios.

Conclusion

CD mortality has increased in Peru. Mortality was higher in men and older adults, and it varied among departments. More political efforts are needed to reduce these trends.

Peru - Progress in health and sciences in 200 years of independence

Peru celebrates 200 years of independence in 2021. Over this period of independent life, and despite the turbulent socio-political scenarios, from internal armed conflict to economic crisis to political instability over the last 40 years, Peru has experienced major changes on its epidemiological and population health profile. Major advancements in maternal and child health as well as in communicable diseases have been achieved in recent decades, and today Peru faces an increasing burden of non-communicable diseases including mental health conditions. In terms of the configuration of the public health system, Peru has also strived to secure country-wide optimal health care, struggling in particular to improve primary health care and intercultural services. The science and technology infrastructure has also evolved, although the need for substantial investments remains if advancing science is to be a national priority. Climate change will also bring significant challenges to population health given Peru's geographical and microclimates diversity. Looking back over the 200-years of independence, we present a summary of key advances in selected health-related fields, thus serving as the basis for reflections on pending agendas and future challenges, in order to look forward to ensuring the future health and wellbeing of the Peruvian population.

Resumen translated abstract

El Perú cumple 200 años de independencia en 2021. Durante estos dos siglos de vida independiente, junto con periodos sociales y políticos turbulentos, incluyendo un conflicto armado interno, hiperinflación y la inestabilidad política de los últimos 40 años, el Perú ha experimentado importantes cambios en su perfil epidemiológico con repercusiones directas en la salud de la población. En las últimas décadas, los indicadores de salud materno-infantil y de las enfermedades transmisibles muestran mejoría importante, pero el país se enfrenta de manera simultánea a una carga cada vez mayor de enfermedades no transmisibles y de salud mental. En cuanto a los sistemas de salud pública, se han realizado esfuerzos por aumentar la cobertura y calidad de la atención de salud en todo el país, apostándose en particular por mejorar la atención primaria. La ciencia y tecnología relacionadas con la salud también han mejorado, aunque si se quiere que la ciencia sea una prioridad nacional, son necesarias inversiones sustanciales. El cambio climático traerá importantes desafíos para la salud de la población, dada la diversidad geográfica y de microclimas del país. Para conmemorar los 200 años de vida independiente del Perú, presentamos un resumen de avances clave en diversas áreas y temas relacionados con la salud. Este repaso sirve como base para reflexionar sobre agendas y desafíos pendientes y futuros, con el fin de asegurar la salud y el bienestar de la población peruana en las próximas décadas.

Metabolic syndrome in rural Peruvian adults living at high altitudes using different cookstoves

This study determined the prevalence of metabolic syndrome (MetS) in open fire stoves and improved cookstoves users (ICS) in the rural Peruvian Andes. Participants answered a socioeconomic questionnaire, one 24-hour food recall and underwent a physical examination. We analysed data from 385 participants, 190 (112 women and 78 men) were ICS users and 195 (123 women and 72 men) were open fire stove users. The prevalence of MetS was 21.3, 26.4% in women and 13.3% in men. We found no statistically significant association between the type of cookstove and MetS. Body mass index and altitude were important determinants of MetS. Research on cardiometabolic diseases and open fire stove use contributes to understanding the effect of household air pollution on health in high altitude populations.

Population-based stroke incidence estimates in Peru: Exploratory results from the CRONICAS cohort study

BACKGROUND

Limited information exists about the incidence of first-ever stroke at the population level, particularly in low- and middle-income countries (LMIC). Longitudinal data from the CRONICAS Cohort Study includes both altitude and urbanization and allows a detailed assessment of stroke incidence in resource constrained settings. The aim of this study was to estimate the incidence and explore risk factors of first-ever stroke at the population level in Peru.

METHODS

Stroke was defined using a standardised approach based on information from cohort participants or family members. This information was adjudicated centrally by trained physicians using common definitions. Time of follow-up was calculated as the difference between date of enrolment and the reported date of the stroke event. Unstandardised and age-standardised, first-ever stroke incidence rate and 95% confidence intervals (95% CI) were calculated. Generalized linear models, assuming Poisson distribution and link log, were utilized to determine potential factors to develop stroke.

FINDINGS

3,601 individuals were originally enrolled in the cohort and 2,471 provided data for the longitudinal analysis. The median time of follow-up was 7.0 (range: 1 - 9) years, accruing a total of 17,308 person-years. During followup, there were 25 incident cases of stroke, resulting in an age-standardised incidence of stroke of 98.8 (95% CI: 63.8 - 154.0) per 100,000 person-years. After adjustment by age and sex, stroke incidence was higher among people with hypertension (incidence risk ratio (IRR) = 5.18; 95% CI: 1.89 - 14.16), but lower among people living at high altitude (IRR = 0.09; 95% CI: 0.01 - 0.63).

INTERPRETATION

Our results indicate a high incidence of first-ever strokes in Peruvian general population. These results are consistent with the estimates found in previous LMIC reports. Our study also found a contributing role of hypertension, increasing the risk of having a first-ever stroke. This work further advances the field of stroke epidemiology by identifying high altitude as a factor related to lower incidence of stroke in a longitudinal study. However, this information needs to be considered with cautions because of the study limitations.

Residential elevation and its effects on hypertension incidence among older adults living at low altitudes: a prospective cohort study

Background

Research on the relationship between residential altitude and hypertension incidence has been inconclusive. Evidence at low altitudes (i.e., <1,500 m) is scarce, let alone in older adults, a population segment with the highest hypertension prevalence. Thus, the objective of this study is to determine whether hypertension risk may be affected by altitude in older adults living at low altitudes.

Methods

This prospective cohort study collected data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS). We selected 6,548 older adults (≥65 years) without hypertension at baseline (2008) and assessed events by the follow-up surveys done in 2011, 2014, and 2018 waves. The mean altitude of 613 residential units (county or district) in which the participants resided was extracted from the Digital Elevation Model (DEM) of the National Aeronautics and Space Administration (NASA) and was accurate to within 30 m. The Cox regression model with penalized splines examined the linear or nonlinear link between altitude and hypertension. A random-effects Cox regression model was used to explore the linear association between altitude and hypertension.

Results

The overall rate of incident hypertension was 8.6 per 100-person years. The median altitude was 130.0 m (interquartile range [IQR] = 315.5 m). We observed that the exposure–response association between altitude and hypertension incidence was not linear. The shape of the exposure–response curve showed that three change points existed. Hypertension risk increased from the lowest to the first change point (247.1 m) and slightly fluctuated until the last change point (633.9 m). The risk decreased above the last change point. According to the categories stratified by the change points, altitude was only significantly associated with hypertension risk (hazard ratio [HR] = 1.003; 95% confidence interval [CI] = 1.002–1.005) under the first change point (247.1 m) after adjusting for related covariates.

Conclusion

Our study found that the association between altitude and hypertension risk might not be linear. We hope the further study can be conducted to confirm the generality of our findings.

Supplementary information

The online version contains supplementary material available at https://doi.org/10.1265/ehpm.22-00001.

Cardiovascular Disease in the Peruvian Andes: Local Perceptions, Barriers, and Paths to Preventing Chronic Diseases in the Cajamarca Region

Objectives: Public health interventions can be improved by understanding peoples' explanatory models of disease. We explore awareness and perceptions of cardiovascular diseases (CVD) and options for preventative actions in young adults living in rural Andean communities. Methods: We used convenience sampling to select 46 men and women from communities in Cajamarca (Peru). Subjects participated in eight focus groups where they discussed their understanding and perceived causes of CVD as well as barriers and pathways to healthy lifestyles. Results: Fresh foods, physical activity, unpleasant emotions, and healthcare access were cited as important determinants of healthy lifestyles. Barriers to healthy diets included lacking nutritional knowledge, fluctuating food prices, and limited access to foodstuffs. Women felt particularly vulnerable to CVD and identified gendered barriers to manage stress and engage in sports. Low health literacy, poor doctor-patient relationships, and long distances prevented participants from fully accessing healthcare. Conclusion: CVD prevention interventions should consider local knowledge of these diseases and of healthy lifestyles, and harness ongoing programmes that have successfully promoted good nutrition in children and pregnant women. In concert with public-private parterships, governments should include disease prevention interventions for the entire family.

Association of altitude and urbanization with hypertension and obesity: analysis of the Nepal Demographic and Health Survey 2016

BACKGROUND

Nepal's Himalayan range attracts mountaineers, climbers and tourists from all across the globe. Limited recent evidence suggests that exposure to hypoxia at a higher altitude may be a risk factor for hypertension and a protective factor for obesity. The existing urban-rural disparities in Nepal in health and economic resources may be anticipated in the burden of hypertension and obesity, two rapidly growing public health issues, but they remain largely unstudied. Therefore this study aims to assess the association of altitude and urbanization with hypertension and overweight/obesity in Nepal.

METHODS

Data on 10 473 participants from a nationally representative survey, the 2016 Nepal Demographic and Health Survey (NDHS), was used. The NDHS assessed/measured blood pressure, height, weight, urbanization and the altitude of participants' households by following standard procedures. Logistic and linear regression models were used to study the association of altitude (per 100 m increases) and urbanization with hypertension and obesity, or their continuous measurements (i.e. systolic and diastolic blood pressure [SBP and DBP, respectively] and body mass index [BMI]).

RESULTS

The prevalence of hypertension, overweight and obesity was 25.6%, 19.6% and 4.8%, respectively. After controlling for covariates, residents of metropolitan cities had a 30% higher prevalence of overweight/obesity (adjusted prevalence ratio 1.30 [95% confidence interval {CI} 1.11 to 1.52]) than their rural counterparts. For altitude, there was a marginally increased odds of hypertension and overweight/obesity with elevation. Consistently, DBP (β = 0.18 [95% CI 0.09 to 0.27]) and BMI increased with altitude (β = 0.11 [95% CI 0.08 to 0.13]).

CONCLUSION

Urbanization was positively associated with BMI, while altitude showed a marginally positive association with hypertension and overweight/obesity. Given the role of obesity and hypertension in the aetiology of other chronic diseases and subsequently associated mortality and health care costs, residents in urban areas and at higher altitudes may benefit from weight control interventions and BP monitoring, respectively.

Impacts of the urinary sodium-to-potassium ratio, sleep efficiency, and conventional risk factors on home hypertension in a general Japanese population

Recently, a high urinary sodium-to-potassium (Na/K) ratio and reduced sleep efficiency, in addition to conventional risk factors (obesity and excess alcohol intake), have been identified as risk factors for hypertension. We estimated the population attributable fraction (PAF) for home hypertension due to these risk factors in a general Japanese population. We conducted a cross-sectional study including 1384 participants (393 men and 991 women) to estimate the odds ratio (OR) and 95% confidence interval (CI) for the presence of any of the conventional risk factors using multivariable logistic regression analyses. The models were adjusted for sex, age, smoking status, and log-transformed average daily steps. We also estimated the OR and 95% CI for the presence of any of the overall risk factors. Furthermore, we calculated the PAF due to these risk factors. The results showed that the prevalence of home hypertension was 39.0% (540/1384). The presence of any of the conventional risk factors, as well as any of the overall risk factors, was significantly associated with an increased prevalence of hypertension (OR 2.80, 95% CI 2.15-3.65; OR 2.50, 95% CI 1.93-3.22, respectively). The PAF for hypertension due to the presence of any of the conventional risk factors and the PAF due to the presence of any of the overall risk factors were 30.2% and 39.0%, respectively. In conclusion, the impact of the overall risk factors, including the urinary Na/K ratio and sleep efficiency, on home hypertension was higher than that of conventional risk factors alone. The management of the urinary Na/K ratio and sleep efficiency as well as conventional risk factors might be important in the management of blood pressure.

Short-term trends in the prevalence, awareness, treatment, and control of arterial hypertension in Peru

The prevalence of hypertension has been declining in low- and middle-income countries (LMIC), particularly in Latin America and the Caribbean. However, we have not identified studies that evaluate trends for awareness, treatment, and control of hypertension in LMIC. We aimed to describe the trends in the prevalence, awareness, treatment, and control of hypertension in Peru. A cross-sectional analysis was conducted using secondary data (4 years) of the Demographic and Health Survey of Peru (ENDES, Spanish acronym), which is conducted annually and is representative at the country level. The age-standardized prevalence was estimated using the World Health Organization population as the reference population. The trend over time was evaluated with the score test for trend of odds. A total of 109,401 participants were included. In Peru, from 2015 to 2018, the age-standardized prevalence of hypertension increased (p < 0.001), while the proportion of people with disease awareness (p < 0.001) and controlled hypertension decreased (p = 0.01). During that same period, the proportion of people with treatment for hypertension did not vary over time (p = 0.13). In 2018, the age-standardized prevalence of hypertension was 20.6%, and the proportion of people with disease awareness, treatment, and control of arterial hypertension was 43.5%, 20.6%, 5.3%, respectively. People with low socioeconomic status and people living in rural areas have the lowest proportion of awareness, treatment, and control of hypertension.

Screening strategies for hypertension

BACKGROUND

Hypertension is a major public health challenge affecting more than one billion people worldwide; it disproportionately affects populations in low- and middle-income countries (LMICs), where health systems are generally weak. The increasing prevalence of hypertension is associated with population growth, ageing, genetic factors, and behavioural risk factors, such as excessive salt and fat consumption, physical inactivity, being overweight and obese, harmful alcohol consumption, and poor management of stress. Over the long term, hypertension leads to risk for cardiovascular events, such as heart disease, stroke, kidney failure, disability, and premature mortality. Cardiovascular events can be preventable when high-risk populations are targeted, for example, through population-wide screening strategies. When available resources are limited, taking a total risk approach whereby several risk factors of hypertension are taken into consideration (e.g. age, gender, lifestyle factors, diabetes, blood cholesterol) can enable more accurate targeting of high-risk groups. Targeting of high-risk groups can help reduce costs in that resources are not spent on the entire population. Early detection in the form of screening for hypertension (and associated risk factors) can help identify high-risk groups, which can result in timely treatment and management of risk factors. Ultimately, early detection can help reduce morbidity and mortality linked to it and can help contain health-related costs, for example, those associated with hospitalisation due to severe illness and poorly managed risk factors and comorbidities.

OBJECTIVES

To assess the effectiveness of different screening strategies for hypertension (mass, targeted, or opportunistic) to reduce morbidity and mortality associated with hypertension.

SEARCH METHODS

An Information Specialist searched the Cochrane Register of Studies (CRS-Web), the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, Latin American Caribbean Health Sciences Literature (LILACS) Bireme, ClinicalTrials.gov, and the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) without language, publication year, or publication status restrictions. The searches were conducted from inception until 9 April 2020.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and non-RCTs (NRCTs), that is, controlled before and after (CBA), interrupted time series (ITS), and prospective analytic cohort studies of healthy adolescents, adults, and elderly people participating in mass, targeted, or opportunistic screening of hypertension.

DATA COLLECTION AND ANALYSIS

Screening of all retrieved studies was done in Covidence. A team of reviewers, in pairs, independently assessed titles and abstracts of identified studies and acquired full texts for studies that were potentially eligible. Studies were deemed to be eligible for full-text screening if two review authors agreed, or if consensus was reached through discussion with a third review author. It was planned that at least two review authors would independently extract data from included studies, assess risk of bias using pre-specified Cochrane criteria, and conduct a meta-analysis of sufficiently similar studies or present a narrative synthesis of the results.

MAIN RESULTS

We screened 9335 titles and abstracts. We identified 54 potentially eligible studies for full-text screening. However, no studies met the eligibility criteria.

AUTHORS' CONCLUSIONS

There is an implicit assumption that early detection of hypertension through screening can reduce the burden of morbidity and mortality, but this assumption has not been tested in rigorous research studies. High-quality evidence from RCTs or programmatic evidence from NRCTs on the effectiveness and costs or harms of different screening strategies for hypertension (mass, targeted, or opportunistic) to reduce hypertension-related morbidity and mortality is lacking.

Analysis of dietary patterns and cross-sectional and longitudinal associations with hypertension, high BMI and type 2 diabetes in Peru

OBJECTIVE

To determine if specific dietary patterns are associated with risk of hypertension, type 2 diabetes mellitus (T2DM) and high BMI in four sites in Peru.

DESIGN

We analysed dietary patterns from a cohort of Peruvian adults in four geographical settings using latent class analysis. Associations with prevalence and incidence of hypertension, T2DM and high BMI were assessed using Poisson regression and generalised linear models, adjusted for potential confounders.

SETTING

Four sites in Peru varying in degree of urbanisation.

PARTICIPANTS

Adults aged ≥35 years (n 3280).

RESULTS

We identified four distinct dietary patterns corresponding to different stages of the Peruvian nutrition transition, reflected by the foods frequently consumed in each pattern. Participants consuming the 'stage 3' diet, characterised by high proportional consumption of processed foods, animal products and low consumption of vegetables, mostly consumed in the semi-urban setting, showed the highest prevalence of all health outcomes (hypertension 32·1 %; T2DM 10·7 %; high BMI 75·1 %). Those with a more traditional 'stage 1' diet characterised by potato and vegetables, mostly consumed in the rural setting, had lower prevalence of hypertension (prevalence ratio; 95 CI: 0·57; 0·43, 0·75), T2DM (0·36; 0·16, 0·86) and high BMI (0·55; 0·48, 0·63) compared with the 'stage 3' diet. Incidence of hypertension was highest among individuals consuming the 'stage 3' diet (63·75 per 1000 person-years; 95 % CI 52·40, 77·55).

CONCLUSIONS

The study found more traditional diets were associated with a lower prevalence of three common chronic diseases, while prevalence of these diseases was higher with a diet high in processed foods and low in vegetables.

Cardiovascular disease risk factor prevalence and estimated 10-year cardiovascular risk scores in Indonesia: The SMARThealth Extend study

BACKGROUND

The brunt of cardiovascular disease (CVD) burden globally now resides within low- and middle-income countries, including Indonesia. However, little is known regarding cardiovascular health in Indonesia. This study aimed to estimate the prevalence of elevated CVD risk in a specific region of Indonesia.

METHODS

We conducted full household screening for cardiovascular risk factors among adults aged 40 years and older in 8 villages in Malang District, East Java Province, Indonesia, in 2016-2017. 10-year cardiovascular risk scores were calculated based on the World Health Organization/International Society of Hypertension's region-specific charts that use age, sex, blood pressure, diabetes status and smoking behaviour.

RESULTS

Among 22,093 participants, 6,455 (29.2%) had high cardiovascular risk, defined as the presence of coronary heart disease, stroke or other atherosclerotic disease; estimated 10-year CVD risk of ≥ 30%; or estimated 10-year CVD risk between 10% to 29% combined with a systolic blood pressure of > 140 mmHg. The prevalence of high CVD risk was greater in urban (31.6%, CI 30.7-32.5%) than in semi-urban (28.7%, CI 27.3-30.1%) and rural areas (26.2%, CI 25.2-27.2%). Only 11% and 1% of all the respondents with high CVD risk were on blood pressure lowering and statins treatment, respectively.

CONCLUSIONS

High cardiovascular risk is common among Indonesian adults aged ≥40 years, and rates of preventive treatment are low. Population-based and clinical approaches to preventing CVD should be a priority in both urban and rural areas.

The Effect of Hypoxia on Cardiovascular Disease: Friend or Foe?

Savla, Jainy J., Benjamin D. Levine, and Hesham A. Sadek. The effect of hypoxia on cardiovascular disease: Friend or foe? High Alt Med Biol. 19:124-130, 2018.-Over 140 million people reside at altitudes exceeding 2500 m across the world, resulting in exposure to atmospheric (hypobaric) hypoxia. Whether this chronic exposure is beneficial or detrimental to the cardiovascular system, however, is uncertain. On one hand, multiple studies have suggested a protective effect of living at moderate and high altitudes for cardiovascular risk factors and cardiovascular disease (CVD) events. Conversely, residence at high altitude comes at the tradeoff of developing diseases such as chronic mountain sickness and high-altitude pulmonary hypertension and worsens outcomes for diseases such as chronic obstructive pulmonary disease. Interestingly, recently published data show a potential role for severe hypoxia as a unique and unexpected therapy after myocardial infarction. In this review, we will discuss the current literature evaluating the effects of altitude exposure and the accompanying hypoxia on health and the potential therapeutic applications of hypoxia on CVD.

The HOMA-IR Performance to Identify New Diabetes Cases by Degree of Urbanization and Altitude in Peru: The CRONICAS Cohort Study

AIMS

Prognostic thresholds to identify new type 2 diabetes mellitus (T2DM) cases using the HOMA-IR have not been defined. We studied the HOMA-IR performance to identify incident T2DM cases and to assess if the thresholds varied according to urbanization and altitude in Peru.

METHODS

Longitudinal analysis. The outcome was incident T2DM cases: self-report diagnosis and fasting glucose. The exposure was the HOMA-IR. Receiver operating characteristic (ROC) curves were plotted, and the area under the ROC curve (AUC) was estimated with 95% confidence intervals (95% CIs). Results are presented overall and stratified by study site (Lima, Tumbes, urban Puno, and rural Puno), rurality (urban, semiurban, and rural), and altitude (low and high).

RESULTS

A total of 3120 participants (mean age: 55.6 years, 51.2% females) contributed data to this analysis. The median baseline HOMA-IR was 1.7 (IQR 1.0-2.9), with median values ranging from 1.1 in rural Puno to 2.0 in Lima and Tumbes (p < 0.001). Overall for incident T2DM, the AUC was 0.69 (95% CI: 0.64-0.74) with an empirical threshold of 2.8 yielding a positive likelihood ratio of 2.30 and a negative one of 0.61; the positive and negative predictive values were 14.6% and 95.7%, respectively. The empirical thresholds varied within the variables of interest, for example, from 0.9 in urban Puno to 2.9 in Lima.

CONCLUSIONS

Using the HOMA-IR to identify incident T2DM cases seems to yield moderate accuracy. The HOMA-IR could help improve identifying people at high risk of T2DM.

Current health status and its risk factors of the Tsarang villagers living at high altitude in the Mustang district of Nepal

Background

Epidemiology of noncommunicable diseases (NCDs) such as obesity and diabetes mellitus (DM) are influenced by multiple hosts and environmental factors. This study aims to investigate the prevalence of NCDs and determine their risk factors among the adults residing in an isolated village situated at a rural highland of Nepal.

Methods

A cross-sectional survey was conducted in a village located at 3570 m. Each 188 randomly selected participants of age ≥ 18 years old answered a questionnaire and took a full physical exam that included biomedical measurements of glycosylated hemoglobin (HbA1c).

Results

The prevalence of intermediate hyperglycemia and DM was 31.6% and 4.6% respectively, and the prevalence of hypoxemia (SpO₂ < 90%) was 27.1%. A multiple logistic regression analysis for factors for the prevalence of glucose intolerance (HbA1c ≥ 6%) revealed older age (odds ratio [OR] 1.11, 95% confidence interval [CI] 1.06–1.16, for every 1 year increase) and SpO₂ (OR for hypoxemia 3.58, 95% CI 1.20–10.68, vs SpO₂ ≥ 90%).

Conclusions

Tibetan highlanders in the remote mountainous Mustang valley of Nepal have high prevalence of impaired glucose metabolism which could be related to hypoxemia imposed by the hypoxic conditions of high altitude living.

Echoes from Gaea, Poseidon, Hephaestus, and Prometheus: environmental risk factors for high blood pressure

High blood pressure (BP) affects over one billion people and is the leading risk factor for global mortality. While many lifestyle and genetic risk factors are well-accepted to increase BP, the role of the external environment is typically overlooked. Mounting evidence now supports that numerous environmental factors can promote an elevation in BP. Broadly speaking these include aspects of the natural environment (e.g., cold temperatures, higher altitude, and winter season), natural disasters (e.g., earthquakes, volcanic eruptions), and man-made exposures (e.g., noise, air pollutants, and toxins/chemicals). This is important for health care providers to recognize as one (or several) of these environmental factors could be playing a clinically meaningful role in elevating BP or disrupting hypertension control among their patients. At the population level, certain environmental exposures may even be contributing to the growing pandemic of hypertension. Here we provide an updated review of the literature linking environment exposures with high BP and outline practical recommendations for clinicians.

Hypertension in Developing Countries: A Major Challenge for the Future

PURPOSE OF REVIEW

Outline recent epidemiologic data regarding hypertension in developing countries, distinguish differences from developed countries, and identify challenges in management and future perspectives.

RECENT FINDINGS

Increased sugar intake, air and noise pollution, and low birth weight are emerging hypertension risk factors. The major challenges in management are difficulties in accurate diagnosis of hypertension and adequate blood pressure control. In contrast to developed countries, hypertension prevalence rates are on the rise in developing countries with no improvement in awareness or control rates. The increasing burden of hypertension is largely attributable to behavioral factors, urbanization, unhealthy diet, obesity, social stress, and inactivity. Health authorities, medical societies, and drug industry can collaborate to improve hypertension control through education programs, public awareness campaigns, legislation to limit salt intake, encourage generic drugs, development and dissemination of national guidelines, and involving nurses and pharmacists in hypertension management. More epidemiologic data are needed in the future to identify reasons behind increased prevalence and poor blood pressure control and examine trends in prevalence, awareness, treatment, and control. National programs for better hypertension control based on local culture, economic characteristics, and available resources in the population are needed. The role of new tools for hypertension management should be tested in developing world.

Parental body mass index and blood pressure are associated with higher body mass index and blood pressure in their adult offspring: a cross-sectional study in a resource-limited setting in northern Peru

OBJECTIVES

High body mass index (BMI) and blood pressure (BP) are major contributors to the high burden of non-communicable diseases in adulthood. Individual high-risk and population approaches for prevention require newer strategies to target these risk factors and focusing on the family to introduce prevention initiatives appears as a promising scenario. Characterisation of the relationship between BMI and BP among the adult members of a given family merits evaluation. We conducted a secondary analysis of an implementation study in Tumbes, Peru, benefiting from data derived from families with at least one adult offspring.

METHODS

The exposures of interest were the BMI, systolic BP (SBP) and diastolic BP (DBP) of the mother and father. The outcomes were the BMI, SBP and DBP of the offspring. Mixed-effects linear regression models were conducted.

RESULTS

The mean age of the offspring, mothers and fathers was 29 (SD: 9.5), 54 (SD: 11.8) and 59 (SD: 11.6) years, respectively. Father's BMI was associated with a quarter-point increase in offspring BMI, regardless of the sex of the offspring. Mother's BMI had a similar effect on the BMI of her sons, but had no significant effect on her daughters'. Mother's SBP was associated with almost one-tenth of mmHg increase in the SBP of the adult offspring. There was no evidence of an association for DBP.

CONCLUSIONS

In families with adult members, the higher the parents' BMI and SBP, the higher their adult offspring's levels will be.

Sodium and Potassium Consumption in a Semi-Urban Area in Peru: Evaluation of a Population-Based 24-Hour Urine Collection

Despite the negative effects of high sodium and low potassium consumption on cardiovascular health, their consumption has not been quantified in sites undergoing urbanization. We aimed to determine the sodium and potassium consumption in a semi-urban area in Peru with a cross-sectional study. 24-h urine samples were collected. The outcomes were mean consumption of sodium and potassium, as well as adherence to their consumption recommendation: <2 g/day and ≥3.51 g/day, respectively. Bivariate analyses were conducted to identify socio-economic and clinical variables associated with the consumption recommendations of 602 participants, complete urine samples were found in 409: mean age of participants was 45.7 (standard deviation (SD): 16.2) years and 56% were women. The mean sodium and potassium consumption was 4.4 (SD: 2.1) and 2.0 (SD: 1.2) g/day. The sodium and potassium recommendation was met by 7.1% and 13.7% of the study sample; none of the participants met both recommendations. People not adherent to the sodium recommendation had higher diastolic (73.1 mmHg vs. 68.2 mmHg, p = 0.015) and systolic (113.1 mmHg vs. 106.3 mmHg, p = 0.047) blood pressure than those who comply with the recommendation. Public health actions ought to be implemented in areas undergoing urbanization to improve sodium and potassium consumption at the population level.

Is the Effect of Body Mass Index on Hypertension Modified by the Elevation? A Cross-Sectional Study of Rural Areas in Japan

Obesity is an established independent risk factor for developing hypertension. A recent study showed that the effect of obesity on hypertension varies by the elevation of the residence area. Thus, we hypothesized that the interaction effect of body mass index (BMI) and elevation has a significant association with hypertension. The first aim of this cross-sectional study was to examine whether BMI was associated with hypertension, after adjustment for covariates. The second aim was to examine whether the interaction term between BMI and elevation was associated with hypertension, after adjustment for covariates. Data were collected from a cross-sectional study conducted in a rural area of Japan in 2016. After excluding participants with missing data (n = 2), data from 729 participants were analyzed. We found that BMI was significantly associated with hypertension. In addition, the interaction term between BMI and elevation had a significant association with hypertension. The findings of the present study support the recent evidence that high BMI is an independent risk factor for hypertension, but its effect varies by elevation. Thus, context-specific interventions could be an effective approach to prevent hypertension in this area.

Measuring high-altitude adaptation

High altitudes (>8,000 ft or 2,500 m) provide an experiment of nature for measuring adaptation and the physiological processes involved. Studies conducted over the past ~25 years in Andeans, Tibetans, and, less often, Ethiopians show varied but distinct O₂ transport traits from those of acclimatized newcomers, providing indirect evidence for genetic adaptation to high altitude. Short-term (acclimatization, developmental) and long-term (genetic) responses to high altitude exhibit a temporal gradient such that, although all influence O₂ content, the latter also improve O₂ delivery and metabolism. Much has been learned concerning the underlying physiological processes, but additional studies are needed on the regulation of blood flow and O₂ utilization. Direct evidence of genetic adaptation comes from single-nucleotide polymorphism (SNP)-based genome scans and whole genome sequencing studies that have identified gene regions acted upon by natural selection. Efforts have begun to understand the connections between the two with Andean studies on the genetic factors raising uterine blood flow, fetal growth, and susceptibility to Chronic Mountain Sickness and Tibetan studies on genes serving to lower hemoglobin and pulmonary arterial pressure. Critical for future studies will be the selection of phenotypes with demonstrable effects on reproductive success, the calculation of actual fitness costs, and greater inclusion of women among the subjects being studied. The well-characterized nature of the O₂ transport system, the presence of multiple long-resident populations, and relevance for understanding hypoxic disorders in all persons underscore the importance of understanding how evolutionary adaptation to high altitude has occurred.NEW & NOTEWORTHY Variation in O₂ transport characteristics among Andean, Tibetan, and, when available, Ethiopian high-altitude residents supports the existence of genetic adaptations that improve the distribution of blood flow to vital organs and the efficiency of O₂ utilization. Genome scans and whole genome sequencing studies implicate a broad range of gene regions. Future studies are needed using phenotypes of clear relevance for reproductive success for determining the mechanisms by which naturally selected genes are acting.

Taste, Salt Consumption, and Local Explanations around Hypertension in a Rural Population in Northern Peru

Interventions to promote behaviors to reduce sodium intake require messages tailored to local understandings of the relationship between what we eat and our health. We studied local explanations about hypertension, the relationship between local diet, salt intake, and health status, and participants' opinions about changing food habits. This study provided inputs for a social marketing campaign in Peru promoting the use of a salt substitute containing less sodium than regular salt. Qualitative methods (focus groups and in-depth interviews) were utilized with local populations, people with hypertension, and health personnel in six rural villages. Participants were 18-65 years old, 41% men. Participants established a direct relationship between emotions and hypertension, regardless of age, gender, and hypertension status. Those without hypertension established a connection between eating too much/eating fried food and health status but not between salt consumption and hypertension. Participants rejected dietary changes. Economic barriers and high appreciation of local culinary traditions were the main reasons for this. It is the conclusion of this paper that introducing and promoting salt substitutes require creative strategies that need to acknowledge local explanatory disease models such as the strong association between emotional wellbeing and hypertension, give a positive spin to changing food habits, and resist the "common sense" strategy of information provision around the causal connection between salt consumption and hypertension.