Socio-economic status and overweight or obesity among school-age children in sub-Saharan Africa - a systematic review

Overweight and obesity among female adolescents in Nigeria; an emerging, but under-reported epidemic

BACKGROUND

Overweight and obesity are increasing at epidemic levels in all ages globally, but there is little nationally representative data on female adolescents in Nigeria. The focus on female adolescents is important because of the negative implications of overweight and obesity on their health and survival, and that of their unborn children.

AIM

To estimate the prevalence and identify the determinants of overweight and obesity among female adolescents in Nigeria.

METHODS

Cross-sectional study using data from the Nigeria demographic and health survey, 2018. A total of 2,721 female adolescents aged 15-19 years were selected using cluster sampling technique. Overweight and obesity were determined using BMI-for-age reference values of World Health Organization and different explanatory variables at the individual, household and community levels were included. Binary logistic regression analysis was used to identify the determinants of overweight/obesity using five models.

RESULTS

The mean age of the respondents was 16.8 ± 1.4 years. The prevalence rate of overweight/obesity was 10.2%, but with a large variation in the geographical and socio-economic distribution. At the crude/unadjusted rate, nearly all the explanatory variables showed a statistically significant association with overweight and obesity, but at the full model which controlled for all the explanatory variables, only the household wealth index retained its statistically significant association, such that female adolescents who were from richer and richest households had about 3 times higher odds of being obese compared to those from the poorest households. (OR: 2.7; p = 0.018; CI: 1.18-6.18), (OR: 2.8; p = 0.027; CI: 1.13-7.06) respectively.

CONCLUSION

The prevalence of overweight/obesity among female adolescents in Nigeria was 10.2%. The household wealth index remained the only factor with a statistically significant association with overweight and obesity after controlling for confounders. Efforts at addressing overweight and obesity among female adolescents in Nigeria should target those from the richer/richest households.

Overadjustment bias in systematic reviews and meta-analyses of socio-economic inequalities in health: a meta-research scoping review

BACKGROUND

Overadjustment bias occurs when researchers adjust for an explanatory variable on the causal pathway from exposure to outcome, which leads to biased estimates of the causal effect of the exposure. This meta-research review aimed to examine how previous systematic reviews and meta-analyses of socio-economic inequalities in health have managed overadjustment bias.

METHODS

We searched Medline and Embase until 16 April 2021 for systematic reviews and meta-analyses of observational studies on associations between individual-level socio-economic position and health outcomes in any population. A set of criteria were developed to examine methodological approaches to overadjustment bias adopted by included reviews (rated Yes/No/Somewhat/Unclear).

RESULTS

Eighty-four reviews were eligible (47 systematic reviews, 37 meta-analyses). Regarding approaches to overadjustment, whereas 73% of the 84 reviews were rated as Yes for clearly defining exposures and outcomes, all other approaches were rated as Yes for <55% of reviews; for instance, 5% clearly defined confounders and mediators, 2% constructed causal diagrams and 35% reported adjusted variables for included studies. Whereas only 2% included overadjustment in risk of bias assessment, 54% included confounding. Of the 37 meta-analyses, 16% conducted sensitivity analyses related to overadjustment.

CONCLUSIONS

Our findings suggest that overadjustment bias has received insufficient consideration in systematic reviews and meta-analyses of socio-economic inequalities in health. This is a critical issue given that overadjustment bias is likely to result in biased estimates of health inequalities and accurate estimates are needed to inform public health interventions. There is a need to highlight overadjustment bias in review guidelines.

Prevalence, causes and contexts of childhood overweight and obesity in the Pacific region: a scoping review

Background

Non-communicable diseases (NCDs) are a major threat to health and development and account for 75% of deaths in the Pacific Islands Countries and Territories (PICTs). Childhood obesity has been identified as a main risk factor for NCDs later in life. This review compiled overweight and obesity (OWOB) prevalence (anthropometric data) for children aged six to 12 years old living in the Pacific region and identified possible related causes.

Methods

We conducted a systematic search using PubMed, Google Scholar and ScienceDirect for articles published between January 1980 and August 2022. We also searched for technical reports from Ministries of Health. Guided by the eligibility criteria, two authors independently read the selected articles and reports to extract and summarise relevant information related to overweight and obesity.

Results

We selected 25 articles, two worldwide analyses of population-based studies and four national reports. Information revealed that childhood OWOB prevalence reached 55% in some PICTs. This review also indicated that age, gender and ethnicity were linked to children's weight status, while dietary practices, sleep time and level of physical activity played a role in OWOB development, as well as the living environment (socio-economic status and food availability), parenting practices and education level.

Conclusion

This review highlighted that anthropometric data are limited and that comparisons are difficult due to the paucity of surveys and non-standardized methodology. Main causes of overweight and obesity are attributed to individual characteristics of children and behavioural patterns, children's socio-economic environment, parenting practices and educational level. Reinforcement of surveillance with standardised tools and metrics adapted to the Pacific region is crucial and further research is warranted to better understand root causes of childhood OWOB in the Pacific islands. More robust and standardized anthropometric data would enable improvements in national strategies, multisectoral responses and innovative interventions to prevent and control NCDs.

Association between dietary Intake, eating behavior, and childhood obesity among children and adolescents in Ethiopia

Introduction

The upsurge of overweight/obesity (OW/OB) among children and adolescents is as a result of complex interactions between lifestyle behaviours and socioeconomic factors. The objective of this study was to determine socioeconomic and sociodemographic factors, dietary intake and eating behaviours of children and adolescents in Ethiopia and their association with OW/OB.

Methods

A cross-sectional study was conducted among 632 children and adolescents-parent dyads. To identify overweight/obese among children and adolescents, body mass index-for-age Z-scores by sex and age relative to WHO 2007 reference was calculated using WHO AnthroPlus software. A multivariable logistic regression model fitted to determine the adjusted associations between the outcome and the predictors selected from the bivariate analyses. Data analysis was carried out using STATA V.15.0.

Results

The proportion of participants with low, medium and high dietary diversity scores was 7.28%, 22.5%, and 70.2%, respectively. Participants aged 13-18 years were less likely to be overweight or obese [adjusted OR (aOR) = 0.40; 95%CI: 0.26, 0.64] to those aged 5-12 years. Children in a family with the richest or highest socioeconomic status (SES) were more likely to be overweight or obese than those in families with the poorest or lowest status. Children and adolescents who consumed soft drinks (sugar-sweetened beverages) four or more times per week [aOR = 3.24; 95%CI: 1.13, 7.95] were more likely to be overweight or obese to those who did not consume soft drinks.

Conclusions

The study identified factors such as younger age (<12 years), high SES and consumption of soft drinks as key contributors to overweight and obesity among children and adolescents. Therefore, interventions targeting behavioural prevention and reduction of overweight and obesity among children and adolescents should be cognizant of the above factors during implementation in order to achieve desired outcomes, further guided by exploratory qualitative studies to identify public perceptions and attitudes affecting dietary practices.

The Relationship between Certain Parental/Household Socio-Economic Characteristics and Female Adolescent Obesity in Montenegro

BACKGROUND

Considering that obesity is characterized today as a public health challenge and an epidemic in many countries in the world and that one of the main predictors for obesity is socio-economic status (SES), the aim of this paper was to assess the relationship between the SES of parents/guardians and female adolescent obesity in Montenegro.

METHODS

A stratified random probability sample method was used, and the number of participants in this study was 596, aged 15.8 ± 0.58, from all three regions in Montenegro. As SES was a factor in this research, specific SES parameters such as household wealth and parental educational level were collected for parent/guardian of each child. The following anthropometric indices were utilized to evaluate nutritional status: body mass index (BMI) and waist to height ratio (WHtR).

RESULTS

Regarding nutritional status, it can be said that no statistically significant difference between female adolescents according to the regions of Montenegro was found. Of all the adolescents in the study, 15.4% of them were above the normal nutrition level as measured by BMI, while 12.2% were classified as obese by the WHtR. Furthermore, the study found a significant negative relationship between a mother's level of education and obesity in female adolescents, with odds ratios of 0.31 (p = 0.035) and 0.19 (p = 0.009) for secondary and high level education, respectively. This suggests that daughters of mothers with higher levels of education are less likely to be obese.

CONCLUSIONS

In regard to the nutritional status of the respondents in this study, their values fell within the normal range compared to the European average. However, the results regarding the relationship between certain SES characteristics and obesity suggest a similarity to developed countries.

Trends in prevalence of overweight and obesity among South African and European adolescents: a comparative outlook

BACKGROUND

South Africa has several national surveys with body weight-related data, but they are not conducted regularly. Hence, data on longitudinal trends and the recent prevalence of adolescent obesity are not readily available for both national and international reporting and use. This study collectively analysed nationally representative surveys over nearly 2 decades to investigate trends in prevalence of adolescent obesity in South Africa. Furthermore, it compared these data with similar continental report for 45 countries across Europe and North America including United Kingdom, Norway, Netherland, Sweden, Azerbaijan, etc. to identify at-risk sub-population for overweight and obesity among adolescents.  METHODS: The study included primary data of adolescents (15 - 19 years) from South African national surveys (N = 27, 884; girls = 51.42%) conducted between 1998 and 2016. Adolescents' data extracted include measured weight, height, sex, parent employment status, monthly allowance received, and family socioeconomic-related variables. Data were statistically analysed and visualized using chi-square of trends, Wald statistics, odds ratio and trend plots, and compared to findings from European survey report (N = 71, 942; girls = 51.23%). South African adolescents' obesity and overweight data were categorized based on World Health Organization (WHO)'s growth chart and compared by sex to European cohort and by family socioeconomic status.

RESULTS

By 2016, 21.56% of South African adolescents were either obese or overweight, similar to the 21% prevalence reported in 2018 among European adolescents. Girls in South Africa showed higher trends for obesity and overweight compared to boys, different from Europe where, higher trends were reported among boys. South African Adolescents from upper socioeconomic families showed greater trends in prevalence of overweight and obesity than adolescents from medium and lower socioeconomic families. Mothers' employment status was significantly associated with adolescents' overweight and obesity.

CONCLUSIONS

Our study shows that by 2016, the prevalence of adolescent obesity was high in South Africa - more than 1 in 5 adolescents - which is nearly similar to that in Europe, yet South African girls may be at a greater odd for overweight and obesity in contrast to Europe, as well as adolescents from high earning families. South African local and contextual factors may be driving higher prevalence in specific sub-population. Our study also shows the need for frequent health-related data collection and tracking of adolescents' health in South Africa.

Dual Burden of Malnutrition Among Adolescents With Hunger Aged 12-15 Years in 41 Countries: Findings From the Global School-Based Student Health Survey

Background: Hunger is a pandemic among adolescents, resulting in both underweight and obesity, and posing a substantial health challenge.

Objective: To estimate the dual burden of malnutrition among adolescents with hunger.

Design: Data were from the Global school-based Student Health Survey (GSHS). In total, data from 26,986 adolescents with hunger across 5 regions and 41 countries between 2010 and 2015 were analyzed in this study. Weighted prevalence and mean estimates of underweight, overweight, and obesity were calculated by gender, age, and country. Prevalence and 95% confidence intervals (CI) were calculated for regional and country-level income.

Results: The total prevalence of underweight, overweight and obesity among young adolescents with hunger was 6.2% (95% CI: 4.4–8.0%), 25.1% (95% CI: 20.3–29.9%) and 8.9% (95% CI: 6.5–11.3%), respectively. Southeast Asia had the highest prevalence of underweight (17.2%; 95% CI: 7.3–27.0%). America had the highest regional prevalence of obesity (11.1%; 95% CI: 7.2–15.1%) and overweight (28.9%; 95% CI: 21.9–35.9%). Low income countries had relatively high prevalence of underweight (11.5%; 95% CI: 3.2–19.9%). High income countries had the highest prevalence of obesity (17.4%; 95% CI: 14.9–19.9%) and overweight (38.7%; 95% CI: 32.0–45.4%). The co-existence of underweight and overweight among adolescents with hunger was highest in the Eastern Mediterranean region, and in upper-middle and high-income countries.

Conclusions: There is a dual burden of underweight and obesity among adolescents with hunger aged 12–15 years, which differs between geographical regions. The integration of targeted interventions and policies is required to simultaneously address both underweight and increasing rates of obesity among adolescents with hunger in different regions.

Small area variations and factors associated with blood pressure and body-mass index in adult women in Accra, Ghana: Bayesian spatial analysis of a representative population survey and census data

BACKGROUND

Body-mass index (BMI) and blood pressure (BP) levels are rising in sub-Saharan African cities, particularly among women. However, there is very limited information on how much they vary within cities, which could inform targeted and equitable health policies. Our study aimed to analyse spatial variations in BMI and BP for adult women at the small area level in the city of Accra, Ghana.

METHODS AND FINDINGS

We combined a representative survey of adult women's health in Accra, Ghana (2008 to 2009) with a 10% random sample of the national census (2010). We applied a hierarchical model with a spatial term to estimate the associations of BMI and systolic blood pressure (SBP) and diastolic blood pressure (DBP) with demographic, socioeconomic, behavioural, and environmental factors. We then used the model to estimate BMI and BP for all women in the census in Accra and calculated mean BMI, SBP, and DBP for each enumeration area (EA). BMI and/or BP were positively associated with age, ethnicity (Ga), being currently married, and religion (Muslim) as their 95% credible intervals (95% CrIs) did not include zero, while BP was also negatively associated with literacy and physical activity. BMI and BP had opposite associations with socioeconomic status (SES) and alcohol consumption. In 2010, 26% of women aged 18 and older had obesity (BMI ≥ 30 kg/m2), and 21% had uncontrolled hypertension (SBP ≥ 140 and/or DBP ≥ 90 mm Hg). The differences in mean BMI and BP between EAs at the 10th and 90th percentiles were 2.7 kg/m2 (BMI) and in BP 7.9 mm Hg (SBP) and 4.8 mm Hg (DBP). BMI was generally higher in the more affluent eastern parts of Accra, and BP was higher in the western part of the city. A limitation of our study was that the 2010 census dataset used for predicting small area variations is potentially outdated; the results should be updated when the next census data are available, to the contemporary population, and changes over time should be evaluated.

CONCLUSIONS

We observed that variation of BMI and BP across neighbourhoods within Accra was almost as large as variation across countries among women globally. Localised measures are needed to address this unequal public health challenge in Accra.

Factors associated with childhood overweight and obesity in Uganda: a national survey

Background

Childhood obesity is an emerging public health problem globally. Although previously a problem of high-income countries, overweight and obesity is on the rise in low- and middle-income countries. This paper explores the factors associated with childhood obesity and overweight in Uganda using data from the Uganda Demographic and Health Survey (UDHS) of 2016.

Methods

We used Uganda Demographic and Health Survey (UDHS) 2016 data of 4338 children less than 5 years. Multistage stratified sampling was used to select study participants and data were collected using validated questionnaires. Overweight and obesity were combined as the primary outcome. Children whose BMI z score was over two were considered as overweight while those with a BMI z score greater than three were considered as obese. We used multivariable logistic regression to determine factors associated with obesity and overweight among children under 5 years of age in Uganda.

Results

The prevalence of overweight and obesity was 5.0% (217/4338) (95% CI: 4.3–5.6), with overweight at 3.9% (168/4338: 95% CI: 3.2–4.3) and obesity at 1.1% (49/4338: 95% CI: 0.8–1.5). Mother’s nutritional status, sex of the child, and child’s age were associated with childhood obesity and overweight. Boys were more likely to be overweight or obese (aOR = 1.81; 95% CI 1.24 to 2.64) compared to girls. Children who were younger (36 months and below) and those with mothers who were overweight or obese were more likely to have obesity or overweight compared to those aged 49–59 months and those with underweight mothers respectively. Children from the western region were more likely to be overweight or obese compared to those that were from the North.

Conclusion

The present study showed male sex, older age of the children, nutritional status of the mothers and region of residence were associated with obesity and overweight among children under 5 years of age.

Associations of Feeding Practices in Early Life and Dietary Intake at School Age with Obesity in 10- to 12-Year-Old Arab Children

Understanding the role in pediatric obesity of early life feeding practices and dietary intake at school age is essential for early prevention. The study aimed to examine associations of early life feeding practices, environmental and health-related exposures, and dietary intake at school age as determinants of obesity in children aged 10-12 years. In an earlier study of 233 healthy infants in two Arab towns in northern Israel, neonatal history, feeding practices, and health information were obtained up to age 18 months. This follow-up study assessed dietary intake and anthropometric measurements at age 10-12 years using the 24 h recall method. Overall, 174 children participated in this study. Almost all (98%) the children were breastfed. The prevalence of obesity at school age was 42%. A multivariable model adjusted for energy intake and socioeconomic status showed positive associations of total fat intake and of weight-for-height z score, but not feeding practices in infancy, with obesity. Higher gestational age at birth was associated with lower odds of obesity at age 10-12 years. In conclusion, in a population with near universal breastfeeding, gestational age at birth, weight indicators but not feeding practices in infancy, and total fat intake at school age were associated with increased likelihood of obesity.

[Socioeconomic inequalities in the prevalence of excess weight and sedentary behavior among Brazilian adolescents]

The scope of this study was to estimate the prevalence of excess weight and a sedentary lifestyle among Brazilian students between 13 and 17 years of age and investigate the magnitude of the socioeconomic inequalities related to these outcomes. A cross-sectional study was carried out based on data from the National School Health Survey (PeNSE) conducted in 2015. Inequalities were evaluated using the Absolute and Relative Index of Inequality. The prevalence of excess weight in Brazil was 24.2%, ranging from 20.7% in the Northeast Region to 27.8% in the Southern Region. The prevalence of a sedentary lifestyle in Brazil was 67.8%, ranging from 61.8 % in the North Region to 70.3% in the Southeast Region. The direct and positive association between better socioeconomic conditions and the prevalence of excess weight and a sedentary lifestyle indicate health inequities in Brazil. The results of this study point to the need to restructure and reinforce public policies directed at adolescents, which should have as guidelines the promotion of a healthy lifestyle and the reduction of health inequities.

Relationship between adiponectin, TNFα, and SHBG in prepubertal children with obesity

BACKGROUND

Sex hormone-binding globulin (SHBG) levels are low in adult subjects with obesity when compared to normal-weight individuals. Obesity is associated with higher tumor necrosis factor alpha (TNFα) plasma levels and lower adiponectin levels. Moreover, we have recently elucidated the molecular mechanisms by which TNFα and adiponectin regulate hepatic SHBG production.

AIM

The main objective of this study was to assess if the adult associations between TNFα, adiponectin, and SHBG are present in prepubertal children.

METHODS

We determined several morphometric and biochemical parameters in normal-weight (n=15) and obese prepubertal (n=51) children, as well as quantified plasma SHBG, TNFα receptor 1 (TNFα-R1), and adiponectin levels.

RESULTS

Our results showed that prepubertal children with obesity had decreased plasma SHBG levels compared to normal-weight controls (67 nmol/L vs 172 nmol/L). Importantly, SHBG plasma levels correlated significantly (P < 0.05) with TNFα (negatively, ßstd= - 0.31) and adiponectin (positively, ßstd= 0.58) suggesting an important role of these two cytokines in determining plasma SHBG levels in prepubertal children.

CONCLUSIONS

Our results suggest that plasma adiponectin levels may play a more important role than TNFα in influencing plasma SHBG levels in our prepubertal population with obesity.

Family characteristics, perceived environment for physical activity, and childhood obesity: An approach with structural equation models

OBJECTIVES

To evaluate the direct and indirect effects of family characteristics and the perceived neighborhood environment on obesity risks among schoolchildren.

METHODS

Through phone contact with the child's mothers/guardians, the perceptions about the aspects of the neighborhood that could limit or promote health. Physical activity, socioeconomic data, self-reported weight and height, and ultra-processed consumption of the respondents were evaluated, in addition to the screen time of both mothers and children. A hybrid model of structural equations was used to test the direct and indirect effects of family and environmental variables on childhood obesity.

SETTING

Belo Horizonte, Minas Gerais, Brazil.

SUBJECTS

A total of 322 children from 9 to 10 years old from municipal schools and their respective mothers/guardians.

RESULTS

Childhood obesity was positively associated with obesity among mothers/guardians and with the latent variable "socioeconomic status (SES)." It was observed that the child's guardians positively influenced childhood obesity through their own habits, such as screen time and consumption of ultra-processed products, with obesity of mothers/guardians as mediators of both associations. There were no direct and indirect effects of the latent variables of the perceived environment in childhood obesity.

CONCLUSION

Family characteristics are important determinants of childhood obesity and should be considered when designing prevention strategies. Parental perceptions of neighborhood characteristics did not have an influence on childhood obesity.

Prevalence of Obesity and Overweight among School-Aged Children in Saudi Arabia and Its Association with Vitamin D Status

BACKGROUND

Childhood obesity is a significant global public health problem. Worldwide data showed an increasing trend over the years. We aimed to explore the prevalence of obesity, and its association with vitamin D status.

METHODS

This cross-sectional study was conducted during the period from 2016 to 2017. The study included 3613 schoolchildren aged 6-19 years in the western, central, and eastern regions in Saudi Arabia. Anthropometric data including age, sex and body mass index (BMI) was collected and the serum 25OH- vitamin D (25OHD) was measured. Age-sex standardized BMI Z-scores using the 2007 World Health Organization growth standards were applied.

RESULTS

Data from 3613 school-aged children (females = 51.8%), with equal percentage of participants from each region were analyzed. Prevalence of obesity and overweight was estimated at 7.1% and 14.4% respectively. An increasing trend was detected with age (p: 0.006). Obesity started to increase at the age of 10 years and continued to increase until 19 years. Most of the obese children (64.2%) had deficient vitamin D levels, compared to 33.7% of them with suboptimal levels and only 2.0% with optimal levels (p: <0.001).

CONCLUSIONS

This large cohort study revealed a high prevalence (21.5%) of obesity and overweight in school children aged between 6-19 years with increasing trend with age.  Children with high BMI showed extremely high prevalence of VDD and VDI. These findings are alarming and point to the need for effective national interventions that include improving and encouraging access to physical activity and exposure to sunlight, educational activities for students, parents, and schoolteachers and possible enrichment of staple food with vitamin D.

Prevalence, incidence, and trends of childhood overweight/obesity in Sub-Saharan Africa: a systematic scoping review

BACKGROUND

The growing burden of non-communicable diseases (NDC), particularly in low-and middle-income countries, poses a significant threat to global health. Obesity and overweight constitute major risk factors of NCDs such as heart diseases, diabetes, and kidney disease, and as a result, contribute significantly to the development of chronic morbidities, reduced quality of life, and increased risk of premature death. This study described evidence on the prevalence, incidence, and trends of childhood overweight and obesity in sub-Sahara Africa (SSA).

METHODS

We conducted a systematic scoping review employing the Arksey and O'Malley framework, Levac et al. recommendations, and the Joanna Briggs Institute guidelines. To obtain relevant published articles for this review, we performed a comprehensive keywords search in PubMed, Google Scholar, Web of Science, and CINAHL via EBSCOhost platform for studies published between 2009 and June 2019. Guided by the eligibility criteria, title and abstracts, as well as the full-text articles were independently screened in parallel by two investigators. All relevant data were independently extracted by two investigators using a piloted form designed in Microsoft and thematic analysis conducted.

RESULTS

Of the 81 included studies obtained from 250,148 potentially eligible articles, the majority (25) conducted in South Africa followed by 18 in Nigeria. Six studies were conducted in Ethiopia (6), Tanzania (5), Kenya (4), Cameroon (4), Ghana (3), Uganda (2), Mozambique (2), and Sudan (2). One study each was conducted in Botswana, Gambia, Lesotho, Mauritius, Seychelles, Togo, and Zimbabwe. The remaining three articles were multi-country studies. Most (81.5%) of the included studies were cross-sectional surveys and the majority (79) focused on both male and female participants. The majority (80/81) of the included studies reported on the prevalence of childhood overweight/obesity, 8 on the trends of childhood overweight/obesity, and one presented evidence on the incidence of childhood overweight and obesity in SSA.

CONCLUSION

This review demonstrates limited studies on childhood overweight/obesity in most SSA countries although the included studies suggest an increasing burden. Considering the consequences of childhood obesity, there is a need for more primary researches to inform policies decision and implementation to halt the rise of childhood obesity/overweight in SSA.

Risk factors and morbidities associated with childhood obesity in sub-Saharan Africa: a systematic scoping review

BACKGROUND

The rising burden of childhood obesity is a major public health concern, particularly in sub-Saharan Africa (SSA), where most health systems are weak and least prepared for complications that may arise. While the need for preventive action is increasingly recognized, policy implementation within the sub-region has often been inadequate, non-systematic, and ad hoc. This study described evidence on the risk factors and morbidities associated with childhood obesity in SSA.

METHODS

Guided by the Arksey and O'Malley framework incorporating the Levac et al. recommendations, and the Joanna Briggs Institute guidelines, we conducted a scoping study to address the research question. Thorough keywords systematic search was conducted for potentially eligible articles in PubMed, Google Scholar, Web of Science, and CINAHL published between 2009 and June 2019. Articles obtained were screened independently by two investigators at the abstract and full text phases using the eligibility criteria. All relevant data were extracted by two investigators in parallel and thematic analysis conducted.

RESULTS

A total of 337,229 articles were obtained from the database search of which 68 satisfied the inclusion criteria and were included for data extraction. These 68 included studies were conducted in 19 countries with the majority, 27.9% (19/68) from South Africa followed by Nigeria with 20.6% (14/68). Six of the included studies were conducted in Ethiopia, 5 studies in Kenya, 4 studies each in Tanzania and Cameroon, and 2 studies each in Ghana, Uganda, and Sudan. Of the 68 included studies, one each was conducted in Botswana, Gambia, Lesotho, Mauritius, Mozambique, Seychelles, Togo, and Zimbabwe. Most (80.9%) of the included studies were cross-sectional, and only one was an intervention trial. Of the 68 included studies, 53 reported on risk factors, 12 reported on morbidities, and 3 reported both risk factors and morbidities. We found no evidence in almost 60% (28/47) of countries included in the World Health Organisation Africa region.

CONCLUSION

This review findings suggest a paucity of literature on the risk factors of childhood obesity and morbidities in most SSA countries. Hence, there is the need to intensify research efforts, especially experimental study designs using innovative strategies to promote healthy lifestyle choices that will prevent or minimize the risks and health consequences of childhood obesity in SSA.

Double Burden of Malnutrition among Female Adolescent Students in Bahir Dar City, Amhara, Ethiopia

BACKGROUND

Globally, nearly a third of the population suffers from at least one form of malnutrition. Both over- and undernutrition are a growing concern in developing countries particularly among female adolescents. This study was aimed at assessing nutritional status and associated factors among female adolescents in secondary schools of Bahir Dar City, Amhara, Ethiopia, 2019.

METHODS

A school-based cross-sectional study was conducted in secondary schools of Bahir Dar City among 682 female adolescent students in 2019. A simple random sampling technique with proportional allocation was used to select study participants. Data were collected using a self-administered questionnaire. Data were entered into Epi Info version 7.1 and analyzed by SPSS version 21. Underweight and overweight statuses of the participants were determined by using the WHO cutoff point. Bivariable and multivariable logistic regressions were used to identify the significance of association at a 95% confidence interval. P value < 0.05 was used to declare statistical significance.

RESULTS

In this study, the prevalence of underweight, overweight, and obesity was 15%, 8.4%, and 4.7%, respectively. Female adolescents found between age groups of 14-16.5 years old (AOR: 1.7, 95% CI: 1.03-2.69), family size ≥ 4 (AOR: 2.8, 95% CI: 1.05-4.99), participants who did not eat meat once per week (AOR: 1.6, 95% CI: 1.90-2.82), and no onset of menarche (AOR: 4.4, 95% CI: 1.21-15.75) were found to be more likely underweight. In addition, adolescents with family monthly income above 6500 Ethiopian birr (AOR: 12.7, 95% CI: 2.47-65.62), who ate meat two times and more per week (AOR: 2.07, 95% CI: 1.47-9.14), and who ate fruit at least once a week (AOR: 0.20, 95% CI: 0.05-0.78) were more likely to be overweight compared with counterparts. Conclusion and Recommendation. The prevalence of underweight and overweight was found to be high. Design evidence-based adolescent nutritional intervention shall be emphasized by the government and other concerned bodies to avert the dual burden of malnutrition.

Overweight/obesity and associated cardiovascular risk factors in sub-Saharan African children and adolescents: a scoping review

INTRODUCTION

Recently, childhood and adolescence overweight/obesity has increased disproportionately in developing countries, with estimates predicting a parallel increase in future cardiovascular disease (CVD) burden identifiable in childhood and adolescence. Identifying cardiovascular risk factors (CVRF) associated with childhood and adolescence overweight/obesity is pivotal in tailoring preventive interventions for CVD. Whilst this has been examined extensively in high-income countries, there is scant consistent or representative data from sub-Saharan Africa (SSA).

OBJECTIVE

This scoping review synthesises contemporary studies on CVRF associated with overweight and obesity in SSA children and adolescents to provide evidence on the current burden of overweight/obesity and CVD in this population.

METHODS

We searched MEDLINE and Google Scholar up to July 31, 2019 for observational and experimental studies and systematic reviews addressing childhood and adolescence overweight/obesity and CVRF in SSA without language restriction. Four investigators working in four pairs, independently selected and extracted the relevant data. The methodological quality of all included studies was assessed.

RESULTS

We included 88 studies with a total of 86,637children and adolescents from 20 SSA countries. The risk of bias was low in 62 (70.5%), moderate 18 (20.5%), and high in eight (9%) studies. Overweight/obesity in SSA children and adolescents is rising at an alarming rate. Its main associations include physical inactivity, unhealthy diets, high socio-economic status, gender and high maternal body mass index. Identified CVRF in overweight/obese SSA children and adolescents are mainly metabolic syndrome, hypertension, dyslipidaemia, diabetes and glucose intolerance. There is a dearth of guidelines or consensus on the management of either childhood overweight/obesity or CVRF in overweight/obese SSA children and adolescents.

CONCLUSION

The current findings suggest an urgent need to review current health policies in SSA countries. Health education and transforming the current obesogenic environment of the SSA child and adolescent into one which promotes physical activity and healthy dietary habits is required.

A 3-year longitudinal study of effects of parental perception of children's ideal body image on child weight change: The Childhood Obesity Study in China mega-cities

This study examined prevalence of childhood overweight and obesity (ov/ob) and central obesity in five mega-cities across China (Beijing, Shanghai, Xi'an, Nanjing and Chengdu); described parental perceptions of children's ideal body image (IBI); and prospectively examined associations between parental perception of child IBI and child weight changes over 3 years. In this NIH-funded, open cohort study, data were collected from students and their parents in 2015, 2016 and 2017 (n = 3298, in 3 waves). Cross-sectional analysis included all 3298 children; longitudinal data analysis used mixed effects models and included 1691 children aged 6-17 years with ≥two body mass index (BMI) measurements during 2015-2017. Ov/ob prevalence based on Chinese age-sex-specific BMI cut-points was 30.0%. Based on waist-to-height ratio (WHtR), the abdominal obesity rate was 19.8%. Parents reported different preferred IBI for boys vs girls, being about 3 times more likely to select ov/ob as ideal for boys than for girls (4.5% vs 1.5%, respectively, P < .001). In longitudinal analysis, children whose parents selected ov/ob as ideal had higher BMI Z-scores and WHtR increase over time than those whose parents selected an average body image (β [SE] = 0.042 [0.011], and β [SE] = 0.010 [0.004], respectively, all P < .05). Ov/ob rates were high among children in major cities in China. Chinese parents preferred a heavier ideal body image for their boys. Health promotion programs should help empower parents and their children to develop appropriate body images and maintain healthy body weight.

Prevalence of overweight and obesity among African primary school learners: a systematic review and meta-analysis

INTRODUCTION

The increasing trend in the global prevalence of childhood overweight and obesity presents a major public health challenge. This study reports the results of a systematic review and meta-analysis to estimate the prevalence of overweight and obesity among primary school learners residing in Africa according to the different body mass index criteria and population level characteristics.

METHODS

A search of multiple databases was conducted to identify relevant research articles published between January 1980 and February 2017. Random effects models were used to pool prevalence data within and across population level characteristics after variance stabilization through arcsine transformation (PROSPERO registration number CRD42016035248).

RESULTS

Data from 45 studies across 15 African countries, and comprising 92,379 and 89,468 participants for overweight and obesity estimates were included. Estimated overweight and obesity prevalence differed significantly across criteria: 10.5% [95% confidence interval, CI: 7.1-14.3] and 6.1% [3.4-9.7] by World Health Organization; 9.5% [6.5-13.0] and 4.0% [2.5-5.9] by International Obesity Task Force; and 11.5% [9.6-13.4] and 6.9% [5.0-9.0] by Centre for Diseases Control, respectively (p = 0.0027 for overweight; p < 0.0001 for obesity). Estimates were mostly higher in urban, and private schools, but generally similar by gender, major geographic regions, publication year and sample size. Substantial heterogeneity in the estimates across and within criteria were not always explained by major study characteristics.

CONCLUSION

Overweight and obesity are prevalent among African primary school learners, particularly those attending urban, and private schools. The results from this meta-analysis could be helpful in making informed decisions on childhood obesity prevention efforts in African countries.

Association between school-level attributes and weight status of Ghanaian primary school children

Background

Little is known about the impact of the school environmental context on the emerging trend of childhood obesity in Africa. We examined the association of the schools’ contextual factors with body mass index (BMI), abdominal obesity and overweight (including obesity) in urban Ghana.

Method

Using cross-sectional data from 543 school children aged 8–11 years attending 14 primary schools, we applied multilevel logistic regressions and linear regression models to investigate the association of child- and school level attributes with overweight, abdominal obesity, and BMI.

Results

We observed significant variance of the random effects of schools in BMI (2.65, p <  0.05), abdominal obesity (0.85, p <  0.05), and overweight (1.41, p < 0.05), with school contextual levels accounting for 19.7, 20.6, and 30.0% of the total variability observed in BMI, abdominal obesity and overweight respectively. Attending high socioeconomic (SES) level school, private school and school with increased after-school recreational facilities were associated with higher BMI. Children were more likely to be overweight if they attended a high SES level school, had access to healthful foods at school, and after-school recreational facilities. With regards to abdominal obesity, attending a school with increased physical activity facilities decreased the odds of abdominal obesity; however the odds increased if they attended a school with access to after-school recreational facilities.

Conclusion

A number of school-level factors were associated with BMI, overweight and abdominal obesity of children in the present study. Our results provide support for improved school environment to reduce overweight.

Childhood Obesity Prevention in Africa: A Systematic Review of Intervention Effectiveness and Implementation

Childhood obesity is of increasing concern in many parts of Africa. We conducted a systematic search and review of published literature on behavioural childhood obesity prevention interventions. A literature search identified peer-reviewed literature from seven databases, and unindexed African journals, including experimental studies targeting children age 2–18 years in African countries, published in any language since 1990. All experimental designs were eligible; outcomes of interest were both behavioural (physical activity, dietary behaviours) and anthropometric (weight, body mass index, body composition). We also searched for process evaluations or other implementation observations. Methodological quality was assessed; evidence was synthesised narratively as a meta-analysis was not possible. Seventeen articles describing 14 interventions in three countries (South Africa, Tunisia and Uganda) were included. Effect scores indicated no overall effect on dietary behaviours, with some beneficial effects on physical activity and anthropometric outcomes. The quality of evidence was predominantly weak. We identified barriers and facilitators to successful interventions, and these were largely resource-related. Our systematic review highlights research gaps in targeting alternative settings to schools, and younger age groups, and a need for more rigorous designs for evaluating effectiveness. We also recommend process evaluations being used more widely.

Prevalence and correlates of overweight and obesity among school children in an urban district in Ghana

Background

There is limited data on risk factors associated with childhood overweight and obesity in Ghanaian school children. Therefore, the aim of this study was to assess the prevalence of overweight and obesity and associated risk factors in Ghanaian school children.

Methods

Data for this study were obtained from a cross-sectional survey of 543 children aged 8 and 11 years, attending private and public primary schools in the Adentan Municipality of Greater Accra Region, Ghana. Anthropometric, dietary, physical activity, sedentary behaviours, sleep duration and socio-demographic data were collected. BMI-for-age Z-scores were used to classify children as overweight/obesity. Multivariable logistic regressions were used to assess the determinants of overweight and obesity.

Results

The overall prevalence of overweight/obesity was 16.4%. Children living in middle (OR = 1.88; 95% CI = 1.01–3.50) and high socioeconomic status (SES) households (2.58; 1.41–4.70) had increased odds of being overweight or obese compared to those living in low SES household. Attending private school (2.44; 1.39–4.29) and watching television for more than 2 h each day (1.72; 1.05–2.82) were significantly associated with increased likelihood of overweight and obesity. Children who slept for more than 9 h a night (0.53; 0.31–0.88) and walked or cycled to school (0.51; 0.31–0.82) had lower odds of being overweight or obese.

Conclusions

A number of modifiable risk factors were associated with overweight and obesity in this study. Public health strategies to prevent childhood obesity should target reduction in television watching time, promoting active transport to and from school, and increasing sleep duration.

Challenges and opportunities to tackle the rising prevalence of diet-related non-communicable diseases in Africa

Africa is experiencing a sharp rise in non-communicable diseases (NCD) related to rapid globalisation and urbanisation leading to shifts in dietary and lifestyle patterns characterised by increased energy intake and physical inactivity. However, unlike more resource-endowed regions, Africa has a double burden of disease: NCD co-exist with infectious diseases including lower respiratory tract infections, HIV/AIDS and diarrhoeal diseases. The African economy is also relatively weaker, making it difficult to cope with this burden. It is postulated that NCD will soon overtake infectious diseases as the number one cause of death in the African region. The recognition of NCD as diseases and obesity as a related risk factor is weak in Africa, compounded by stigma associated with wasting in HIV/AIDS and obesity being perceived as a sign of wealth, achievement and care. There is also a dearth of data on overweight and obesity in the region and little knowledge that infant feeding practices, such as breast-feeding, are linked to reduced risk of NCD in both children and mothers. While complex multi-sectoral approaches to address this NCD menace are needed, Africa may benefit from taking simple initial steps to address NCD risk factors including: (1) behaviour change communication to challenge perceptions on NCD; (2) promoting and protecting breast-feeding; (3) formulating policies and regulations limiting wide availability of unhealthy foods; (4) mainstream nutrition education in school curricula and (5) collection of accurate data based on indicators that can reflect the double burden of disease and malnutrition; and fostering multi-sectoral actions against NCD.

Overweight and Obesity Among School-aged Children and Maternal Preventive Practices against Childhood Obesity in Select Local Government Areas of Lagos, Southwest, Nigeria

BACKGROUND

Childhood obesity is an emerging epidemic in the developing countries, particularly in the urban settings. This study examines the prevalence of overweight and obesity among school-aged children and the maternal preventive practices against childhood obesity.

METHODS

This is a cross-sectional study of school-aged children aged 6-13 years and mothers from two Local Government Areas of Lagos State, Southwest Nigeria. Multi-stage sampling technique was used to select study areas and participants, while data were collected using an interviewer administered questionnaire. The Body Mass Index (BMI) of children were determined using the World Health Organisation (WHO) 2007 reference charts. Chi-square test was used to analyze categorical variables and logistic regression analyses were conducted to determine the factors associated with the nutritional status and maternal childhood obesity preventive practices. All analyses were conducted using the Statistical Package for Social Sciences (SPSS) 21.

RESULTS

In all, 440 children comprising of 232 boys (52.7%) and 208 girls (42.3%) were studied. Of these, 29 of the participants (6.6%) were overweight, while 39 of them (8.9%) were obese. Most of the children (71.2%) consumed root/tubers and processed cereals while 9 (0.02%) and (17) 0.04% consumed fruits and vegetables. BMI was only significantly related to child age and sex. In all, 243 mothers (55.2%) had good practices against childhood obesity. Levels of maternal preventive practices were not significantly associated with child BMI.

CONCLUSIONS AND GLOBAL HEALTH IMPLICATIONS

Overweight/obesity among school-aged children in Lagos is high. Only half of the mothers were involved in preventive practices against childhood obesity. There is need for continuous education and advocacy concerning healthy diet and other preventive strategies against childhood obesity in Lagos, and potentially other parts of the developing world.

Caries-related risk factors of obesity among 18-year-old adolescents in Hong Kong: a cross-sectional study nested in a cohort study

BACKGROUND

Socio-economic status, health awareness, and dietary habits have been reported as common risk factors of dental caries and obesity. The present study aimed to explore shared mediators between caries and obesity and to estimate the effects of caries-related factors on adiposity.

METHODS

This was a cross-sectional study among adolescents aged 18 years. The study was nested in a population-representative cohort of Chinese in Hong Kong. The number of decayed, missing, and filled permanent teeth (DMFT) was recorded during the oral examinations. Body Mass Index (BMI), Waist Circumference (WC), Waist-Hip-Ratio (WHR), Waist-Height-Ratio (WHtR), and Triceps Skinfold Thickness (TRSKF) were used as adiposity indices. Data on socio-economic status, oral health behavior (tooth brushing habit, use of fluoride toothpaste, dental flossing habit, and mouth rinse habit), and dietary record (frequency and amount of different food) were collected through self-completed questionnaires. Chi-square tests and binary logistic regressions were used for analysis.

RESULTS

Three hundred eighty-three participants were included. The mean (standard deviation, SD) of BMI, WC, WHR, WHtR, TRSKF, and DMFT were 21.26 (3.72), 69.11 (9.25), 0.77 (0.06), 0.42 (0.05), 15.72 (6.33), and 2.06 (2.43), respectively. Males were more likely to be overweight/obese than females. Various factors including gender, parental employment status, mouth rinse habit, frequency and amount of meat intake, frequency of oil intake, use of fluoride toothpaste, and DMFT were found significant (p < 0.05) in different final models of adiposity status.

CONCLUSIONS

More mediators should be included in future research to elucidate mechanism of the association between caries and obesity.

Inequalities in oral health among adolescents in Gangneung, South Korea

Background

This study aims to evaluate inequality in oral health among adolescents and to explain the mechanisms of such inequalities in Gangneung, South Korea.

Methods

One thousand two hundred sixty-seven students in their first year from four vocational and three general schools participated in the baseline survey of 2011, and 84.7% of them were surveyed again in 2013. Oral examinations by the same dentist and a self-administered questionnaire were repeated during both waves. Outcome measure for oral health was the existence of untreated dental caries (DT). As socioeconomic position (SEP) indicators, school type (general vs. vocational), father’s and mother’s education, perceived economic status, and Family Affluence Scale (FAS) were measured. Variables measuring oral health related behaviours included tooth brushing frequency, frequency of eating snacks and drinking sodas, smoking, and annual visits to dental clinics. Chi-square tests and panel logistic regression were adopted to examine the associations between dental caries and SEP indicators by STATA version 15.1.

Results

Having a less educated father and attending a vocational school were significant predictors for untreated caries after controlling for SEP indicators. However, students from general schools, higher SEP by father’s education, perceived economic status, or FAS, or having non-smoking experience or annual visits to dental clinics were more likely to stay caries-free.

Conclusions

There were socioeconomic inequalities in oral health on an adolescent panel. Given that oral health status during adolescents can persist throughout the course of a person’s life, intervention to tackle such inequalities and school environments are required.

Electronic supplementary material

The online version of this article (10.1186/s12903-018-0533-3) contains supplementary material, which is available to authorized users.

Prevalence and trends of obesity among adult Sudanese individuals: Population based study

AIM

The prevalence of obesity has increased across the globe in particular in Africa. The aim of this study was to determine the prevalence of obesity in Sudan.

MATERIAL AND METHODS

Descriptive, cross sectional study recruited 7239 individuals. Demographic and clinical data were collected by an interview using a pretested standardised questionnaire. Anthropometric measurements including body weight, height and waist circumference have been taken using standardized techniques and calibrated equipment. Body mass index (BMI) has been calculated.

RESULTS

Total of 7239 persons completed the questionnaires; the results showed that prevalence of obesity was found to be 21.2%, with a higher rate of obesity in females than males (26.3% versus 13.8%). The prevalence of central obesity was also higher in women (36.7%) than men (17.6%).The prevalence of overweight was 34.9%. The overall prevalence of overweight/obesity was 56.1%. Obesity determined by BMI was associated with hypertension and diabetes. While central obesity was associated with an increase in age, female, diabetes and hypertension.

CONCLUSION

The prevalence of obesity was 21.2%. Obesity and central obesity have a higher prevalence among Sudanese women. Obesity and central obesity were associated with diabetes and hypertension.

Undernutrition and obesity among elderly people living in two cities of developing countries: Prevalence and associated factors in the EDAC study

BACKGROUND

Nutritional status among elderly people living in Sub-Saharan Africa is poorly studied, even though undernutrition and obesity are known to cause many complications and are risk factors for progression and death in several diseases. The aims of this study were to assess the nutritional status of the elderly in Central Africa and to study the factors associated with nutritional disorders (undernutrition and obesity).

METHODS

Two cross-sectional population-based studies were carried out in the capitals of Central African Republic (CAR) and Republic of Congo (ROC) between 2008 and 2009. Participants were aged ≥65 years old and underwent nutritional assessment including the following measurements: weight, height, body mass index (BMI), waist circumference (WC). Diet was also investigated. Nutritional status was defined according to the WHO BMI classification (<18.5 = undernutrition; ≥30 = obesity). Multinomial regression analysis was performed in order to identify factors associated with nutritional status.

RESULTS

990 elderly people underwent nutritional assessment (482 in CAR and 508 in ROC). Mean BMI was 22.7 ± 4.8 kg/m². The prevalence of undernutrition was 19.2% and was lower in ROC than in CAR (9.5% vs. 29.5%; p < 0.0001). The prevalence of obesity was 8.8% and was higher in ROC than in CAR (14.6% vs. 2.7%; p < 0.0001). The mean WC was 85.3 ± 28.4 cm. Adjusted on study site, increasing age (OR = 1.6 [95% CI: 1.1-2.3] for 75-84 years, OR = 2.6 [95% CI: 1.4-4.8] for 85+ years), occupation as farmer/breeder (OR = 2.2 [95% CI: 1.1-4.2]), smoking (OR = 1.71 [95% CI: 1.14-2.56]) and low sugar consumption (OR = 1.7 [95% CI: 1.1-2.7]) were positively associated with undernutrition whereas only female sex was positively associated with obesity (OR = 5.0 [95% CI: 2.2-11.0]).

CONCLUSIONS

The prevalence of undernutrition is high in the elderly population of these countries, in contrast to obesity. Undernutrition and obesity are associated with different socio-economic factors and food consumption. Simple nutritional advice could contribute to improving the nutritional status of elderly people in Central Africa.