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Background: Evidence on cognitive function in older South Africans is limited, with few population-based studies. We aimed to estimate baseline associations between cognitive function and cardiometabolic disease risk factors in rural South Africa., Methods: We use baseline data from "Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in South Africa" (HAALSI), a population-based study of adults aged 40 and above in rural South Africa in 2015. Cognitive function was measured using measures of time orientation, immediate and delayed recall, and numeracy adapted from the Health and Retirement Study cognitive battery (overall total cognitive score range 0-26). We used multiple linear regression to estimate associations between cardiometabolic risk factors (including BMI, hypertension, dyslipidemia, diabetes, history of stroke, alcohol frequency, and smoking status) and the overall cognitive function score, adjusted for potential confounders., Results: In multivariable-adjusted analyses (n = 3018; male = 1520; female = 1498; median age 59 (interquartile range 50-67)), cardiometabolic risk factors associated with lower cognitive function scores included: diabetes (b = - 1.11 [95% confidence interval: - 2.01, - 0.20] for controlled diabetes vs. no diabetes); underweight BMI (b = - 0.87 [CI: - 1.48, - 0.26] vs. normal BMI); and current and past smoking history compared to never smokers. Factors associated with higher cognitive function scores included: obese BMI (b = 0.74 [CI: 0.39, 1.10] vs. normal BMI); and controlled hypertension (b = 0.53 [CI: 0.11, 0.96] vs. normotensive)., Conclusions: We provide an important baseline from rural South Africa on the associations between cardiometabolic disease risk factors and cognitive function in an older, rural South African population using standardized clinical measurements and cut-offs and widely used cognitive assessments. Future studies are needed to clarify temporal associations as well as patterns between the onset and duration of cardiometabolic conditions and cognitive function. As the South African population ages, effective management of cardiometabolic risk factors may be key to lasting cognitive health.

Background: To report associations between different adiposity indices [anthropometric and dual-energy X-ray absorptiometry (DXA) measures] and blood pressure (BP) and hypertension in urban black South African adults., Methods: Anthropometric and DXA whole body measures were performed on 1026 men and 982 women. Participants were classified as being hypertensive if they had a systolic BP (SBP) ≥ 140 mmHg and/or diastolic (DBP) ≥ 90 mmHg. Within each gender the relationship of adiposity with BP and hypertension risk was assessed using linear and logistic regression models respectively. Bivariate models were computed for each body composition variable. Furthermore, we computed a multiple regression model to illustrates how body composition parameters are associated with the outcome variables independent of each other., Results: The males were significantly taller and had a higher fat free soft tissue mass (FFSTM), DBP and socio-economic status, and were more likely to use tobacco and be hypertensive (48.0% vs. 38.8%). The females had higher body mass index (BMI), waist circumference (WC), fat mass (FM), subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT), FM/FFSTM ratio and body fat % than males. All body composition parameters were positively associated with hypertension. In both males and females, the FM/FFSTM ratio associated the strongest with hypertension illustrating the following odds ratios [males: 70.37 (18.47, 268.16) p ≤ 0.001; females 2.48 (0.86,7.21) p = 0.09]. The multiple regression model, indicated that the VAT and WC significantly associated with both SBP and DBP in the men and women respectively, whilst WC was the only significant predictor for hypertension., Conclusions: All body composition parameters were associated with hypertension and FM/FFSTM ratio showed the strongest relationship. It was reassuring that WC remains a useful measure of central adiposity that can be used as a risk indicator for hypertension if more sophisticated measures are not available. Furthermore, our data in part, implies that reducing abdominal adiposity in aging adults could contribute to reducing the risk of elevated blood pressure and hypertension.

Background: A consequence of the widespread uptake of anti-retroviral therapy (ART) is that the older South African population will experience an increase in life expectancy, increasing their risk for cardiometabolic diseases (CMD), and its risk factors. The long-term interactions between HIV infection, treatment, and CMD remain to be elucidated in the African population. The HAALSI cohort was established to investigate the impact of these interactions on CMD morbidity and mortality among middle-aged and older adults., Methods: We recruited randomly selected adults aged 40 or older residing in the rural Agincourt sub-district in Mpumalanga Province. In-person interviews were conducted to collect baseline household and socioeconomic data, self-reported health, anthropometric measures, blood pressure, high-sensitivity C-reactive protein (hsCRP), HbA1c, HIV-status, and point-of-care glucose and lipid levels., Results: Five thousand fifty nine persons (46.4% male) were enrolled with a mean age of 61.7 ± 13.06 years. Waist-to-hip ratio was high for men and women (0.92 ± 0.08 vs. 0.89 ± 0.08), with 70% of women and 44% of men being overweight or obese. Blood pressure was similar for men and women with a combined hypertension prevalence of 58.4% and statistically significant increases were observed with increasing age. High total cholesterol prevalence in women was twice that observed for men (8.5 vs. 4.1%). The prevalence of self-reported CMD conditions was higher among women, except for myocardial infarction, and women had a statistically significantly higher prevalence of angina (10.82 vs. 6.97%) using Rose Criteria. The HIV - persons were significantly more likely to have hypertension, diabetes, or be overweight or obese than HIV + persons. Approximately 56% of the cohort had at least 2 measured or self-reported clinical co-morbidities, with HIV + persons having a consistently lower prevalence of co-morbidities compared to those without HIV. Absolute 10-year risk cardiovascular risk scores ranged from 7.7-9.7% for women and from 12.5-15.3% for men, depending on the risk score equations used., Conclusions: This cohort has high CMD risk based on both traditional risk factors and novel markers like hsCRP. Longitudinal follow-up of the cohort will allow us to determine the long-term impact of increased lifespan in a population with both high HIV infection and CMD risk.

Background: Urban black South African women have a high prevalence of non-communicable diseases such as obesity and type 2 diabetes. The aim of this study was to assess the physical activity patterns of a cohort of middle-aged urban-dwelling black African women and to determine if physical activity is associated with anthropometric measures and metabolic outcomes in this population., Methods: Physical activity and sitting time were assessed using the Global Physical Activity Questionnaire (GPAQ) in a cross-sectional study of 977 black African women (mean age 41.0 ± 7.84 years) from the Birth to Twenty study based in Soweto, Johannesburg. Anthropometric outcomes were measured and fasting blood glucose, insulin and lipid profile were analysed to determine metabolic disease risk and prevalence., Results: Sixty-seven percent of the population were classified as active according to GPAQ criteria, and the domain that contributed most to overall weekly physical activity was walking for travel. Only 45.0% of women participated in leisure time activity. The prevalence of metabolic syndrome in this sample was 40.0%, and the prevalence of overweight and obesity was 29.2% and 48.0%, respectively. Women who reported owning a motor vehicle walked for travel less, and participated in more leisure-time activity (both p < 0.01), while women who owned a television reported significantly lower moderate-vigorous physical activity (MVPA), and walking for travel (both p < 0.01). Sitting time (mins/wk) was not different between the activity groups, but was associated with triglycerides and diastolic blood pressure. Total physical activity was inversely associated with fasting insulin, and physical activity in the work domain was associated with fat free soft tissue mass., Conclusions: The findings of this study show that the majority of urban dwelling black South African women are classified as physically active despite a high prevalence of obesity and metabolic disease risk factors. Sitting time had detrimental effects on both triglyceride levels and diastolic blood pressure whilst total physical activity attenuated fasting insulin levels. As walking for travel is a major contributor to physical activity, future research should attempt to determine whether the intensity of this activity plays a role in the prevention of cardiometabolic diseases.