Dataset Information

Sociodemographic, socioeconomic, clinical and behavioural predictors of body mass index vary by sex in rural South African adults-findings from the AWI-Gen study.

ABSTRACT:

Background

Despite increasing obesity in South African adults, data on the prevalence and determinants of body mass index (BMI) from rural communities, home to a significant proportion of the population, are scarce.

Objectives

To investigate overall and sex-specific determinants of BMI in a rural adult South African population undergoing rapid social and epidemiological transitions.

Methods

Baseline cross-sectional demographic, socioeconomic, anthropometric, clinical and behavioural data were collected between 2015 and 2016 from 1388 individuals aged 40-60 years and resident in the Agincourt sub-district of Mpumalanga province, a setting typical of rural northeast South Africa. A Health and Socio-Demographic Surveillance System (HDSS) underpins the sub-district and contributes to the Africa Wits-INDEPTH partnership for Genomic Studies (AWI-Gen). Linear regression was used to investigate univariate associations between log-transformed BMI and individual variables and multiple linear regression was used to investigate independent predictors of BMI overall and in sex-stratified analyses.

Results

Median BMI was significantly higher in females (28.7 kg/m²[95% CI 24.2-33.2] vs 23.0 kg/m²[95% CI 20.3-26.8];p < 0.001) with male sex associated with 17% lower BMI. In sex-stratified multiple linear regression models, compared to those never married, BMI was 7% higher in currently married males and 6% in currently married females. Current smoking in men and former smoking in women were associated with reductions in BMI of 13% and 26% respectively, compared with non-smokers. Higher educational attainment in women and higher socioeconomic status in men were both associated with higher BMI, while being HIV-positive and alcohol consumption in women were associated lower BMI.

Conclusions

Female sex strongly predicts higher BMI in this rural African population. While some predictors of higher BMI differ by sex, married individuals in both sexes had a higher BMI, suggesting that, in addition to developing sex-specific interventions to combat overweight and obesity, targeting married couples may result in reduction in population BMI.

SUBMITTER: Wagner RG

PROVIDER: S-EPMC6282437 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Publications

Sociodemographic, socioeconomic, clinical and behavioural predictors of body mass index vary by sex in rural South African adults-findings from the AWI-Gen study.

Wagner Ryan G RG Crowther Nigel J NJ Gómez-Olivé F Xavier FX Kabudula Chodziwadziwa C Kahn Kathleen K Mhembere Memory M Myakayaka Zola Z Tollman Stephen S Wade Alisha N AN

Global health action 20180101 sup2

<h4>Background</h4>Despite increasing obesity in South African adults, data on the prevalence and determinants of body mass index (BMI) from rural communities, home to a significant proportion of the population, are scarce.<h4>Objectives</h4>To investigate overall and sex-specific determinants of BMI in a rural adult South African population undergoing rapid social and epidemiological transitions.<h4>Methods</h4>Baseline cross-sectional demographic, socioeconomic, anthropometric, clinical and be ...[more]

PMID: 30499746

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Project description:Background and objectivesUnderstanding the social determinants of health is a major goal in evolutionary biology and human health research. Low socioeconomic status (often operationalized as absolute material wealth) is consistently associated with chronic stress, poor health and premature death in high-income countries. However, the degree to which wealth gradients in health are universal-or are instead made even steeper under contemporary, post-industrial conditions-remains poorly understood.MethodologyWe quantified absolute material wealth and several health outcomes among a population of traditional pastoralists, the Turkana of northwest Kenya, who are currently transitioning toward a more urban, market-integrated lifestyle. We assessed whether wealth associations with health differed in subsistence-level versus urban contexts. We also explored the causes and consequences of wealth-health associations by measuring serum cortisol, potential sociobehavioral mediators in early life and adulthood, and adult reproductive success (number of surviving offspring).ResultsHigher socioeconomic status and greater material wealth predicts better self-reported health and more offspring in traditional pastoralist Turkana, but worse cardiometabolic health and fewer offspring in urban Turkana. We do not find robust evidence for either direct biological mediators (cortisol) or indirect sociobehavioral mediators (e.g. adult diet or health behaviors, early life experiences) of wealth-health relationships in either context.Conclusions and implicationsWhile social gradients in health are well-established in humans and animals across a variety of socioecological contexts, we show that the relationship between wealth and health can vary within a single population. Our findings emphasize that changes in economic and societal circumstances may directly alter how, why and under what conditions socioeconomic status predicts health.Lay summaryHigh socioeconomic status predicts better health and more offspring in traditional Turkana pastoralists, but worse health and fewer offspring in individuals of the same group living in urban areas. Together, our study shows that under different economic and societal circumstances, wealth effects on health may manifest in very different ways.

Project description:BACKGROUND:Rapid epidemiological health transitions occurring in vulnerable populations in Africa that have an existing burden of infectious and non-communicable diseases predict an increased risk and consequent prevalence of kidney disease. However, few studies have characterised the true burden of kidney damage and associated risk factors in Africans. We investigated the prevalence of markers for kidney damage and known risk factors in rural and urban settings in sub-Saharan Africa. METHODS:In this cross-sectional population study (Africa Wits-International Network for the Demographic Evaluation of Populations and their Health Partnership for Genomic Studies [AWI-Gen]), we recruited unrelated adult participants aged 40-60 years from four rural community research sites (Nanoro, Burkina Faso; Navrongo, Ghana; Agincourt and Dikgale, South Africa), and two urban community research sites (Nairobi, Kenya; and Soweto, South Africa). Participants were identified and selected using random sampling frames already in use at each site. Participants completed a lifestyle and medical history questionnaire, had anthropometric and blood pressure measurements taken, and blood and urine samples were collected. Markers of kidney damage were defined as low estimated glomerular filtration rate (eGFR; <60 mL/min per 1·73 m2), presence of albuminuria (urine albumin creatinine ratio >3 mg/mmol); or chronic kidney disease (low eGFR or albuminuria, or both). We calculated age-adjusted prevalence of chronic kidney disease, low eGFR, and albuminuria by site and sex and used logistic regression models to assess risk factors of kidney damage. FINDINGS:Between August, 2013, and August, 2016, we recruited 10?702 participants, of whom 8110 were analysable. 4120 (50·8%) of analysable participants were male, with a mean age of 49·9 years (SD 5·8). Age-standardised population prevalence was 2·4% (95% CI 2·1-2·8) for low eGFR, 9·2% (8·4-10·0) for albuminuria, and 10·7% (9·9-11·7) for chronic kidney disease, with higher prevalences in South African sites than in west African sites (14·0% [11·9-16·4] in Agincourt vs 6·6% [5·5-7·9] in Nanoro). Women had a higher prevalence of chronic kidney disease (12·0% [10·8-13·2] vs 9·5% [8·3-10·8]) and low eGFR (3·0% [2·6-3·6] vs 1·7% [1·3-2·3]) than did men, with no sex-specific differences for albuminuria (9·9% [8·8-11·0] vs 8·4% [7·3-9·7]). Risk factors for kidney damage were older age (relative risk 1·04, 95% CI 1·03-1·05; p<0·0001), hypertension (1·97, 1·68-2·30; p<0·0001), diabetes (2·22, 1·76-2·78; p<0·0001), and HIV (1·65, 1·36-1·99; p<0·0001); whereas male sex was protective (0·85, 0·73-0·98; p=0·02). INTERPRETATION:Regional differences in prevalence and risks of chronic kidney disease in sub-Saharan Africa relate in part to varying stages of sociodemographic and epidemiological health transitions across the area. Public health policy should focus on integrated strategies for screening, prevention, and risk factor management in the broader non-communicable disease and infectious diseases framework. FUNDING:National Human Genome Research Institute, Office of the Director, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institute of Environmental Health Sciences, the Office of AIDS Research, and National Institute of Diabetes and Digestive and Kidney Diseases, all of the National Institutes of Health, and the South African Department of Science and Technology.

Project description:Dyslipidaemia is a primary risk factor for cardiometabolic disease, causing over 17 million deaths globally in 2015. However, the burden of dyslipidaemia and factors associated with lipid levels remain unknown in many rural African populations. Therefore, this study evaluated the association of socio-demographic, anthropometric and behavioural factors with lipid levels in rural Ghana. The prevalence of hypercholesterolaemia, hypertriglyceridaemia and elevated LDL-C in the total population of 1839 (846 men and 993 women) was 4.02%, 2.12%, and 5.55% respectively and did not differ between genders. The prevalence of low HDL-C levels was 60.30% and differed (p = 0.005) between men (56.86%) and women (63.24%). Subcutaneous abdominal fat was associated with TC (? = 0.067, p = 0.015) and TG (? = 0.137, p<0.001) among women and LDL-C (? = 0.139, p = 0.006) and TC (? = 0.071, p = 0.048) among men. Body mass index was associated with TC (? = 0.010, p = 0.043) among men while waist circumference was associated with LDL-C (? = 0.116, p<0.001) and TG (? = 0.094, p<0.001) among women. Hip circumference was negatively associated (? = -0.053, p = 0.043) while visceral fat was positively associated with TG (? = 0.033, p = 0.022) among women. Socioeconomic status, education, being unmarried and employment were associated with HDL-C (? = 0.081, p = 0.004), LDL-C (? = 0.095, p = 0.004) and TG (? = 0.095, p = 0.001) all among women, and TC (? = 0.070, p = 0.010) among men, respectively. Nankana women had lower TC (? = -0.069, p = 0.001), and men lower TG levels (? = -0.084, p = 0.008) than the other ethnic groups. Tobacco smoking (? = 0.066, p = 0.024) and alcohol intake (? = 0.084, p = 0.001) were associated with HDL-C levels among men and women respectively. Further studies are required to investigate whether high prevalence of low HDL-C levels in this population presents with any adverse cardiovascular disease outcomes. Associations of education, employment and adiposity with lipid levels suggest that future societal advances and increases in the prevalence of obesity may lead to associated adverse health consequences. Monitoring and interventions are required to limit these effects.

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Dataset Information

Sociodemographic, socioeconomic, clinical and behavioural predictors of body mass index vary by sex in rural South African adults-findings from the AWI-Gen study.

Background

Objectives

Methods

Results

Conclusions

Publications

Sociodemographic, socioeconomic, clinical and behavioural predictors of body mass index vary by sex in rural South African adults-findings from the AWI-Gen study.

Similar Datasets

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