Spatial distribution and role of neighborhood characteristics in co-morbidity of HIV and chronic non-communicable disease in an informal township in South Africa

To develop context-appropriate prevention strategies, it is essential to consider neighborhood characteristics beyond the individual level. A randomized household cross-sectional survey was conducted in Diepsloot, South Africa, to examine the prevalence and spatial distribution of biologically-assessed HIV, hypertension, diabetes, and obesity at the neighborhood level. The survey involved 1231 participants, with nearly 50% (n=576) being overweight or obese, 29% (n=359) being hypertensive, 16% being HIV-positive, and 3% (n=42) being diabetic. Women were more likely than men to be overweight/obese (66% vs. 26%) or HIV-positive (21% vs 10%). People living with HIV were less likely than those not living with HIV to have a NCD (56% vs 61%, p=0.2). Geographic hotspots of hypertension, diabetes, and obesity prevalence predominantly overlapped, whereas NCD hotspots only partly overlapped with HIV prevalence hotspots. The study used log binomial regression to identify neighborhood factors associated with prevalent chronic disease, stratified by HIV status. The results showed that people living with HIV and ≥1 NCD were more likely to live far from (>300 meters) a supermarket (Prevalence Ratio(PR)=1.21, 95% CI 0.97-1.51), and less likely to be male (PR=0.65, 95%CI: 0.47-0.89) or to have migrated to South Africa (PR=0.50, 95%CI: 0.32-0.78). These findings suggest that neighborhood access to healthy foods may influence chronic disease burden and may be a feasible target for intervention in Diepsloot. The study observed a high prevalence of HIV and NCDs in a poor urban South African setting. HIV/NCD co-morbidity was associated with gender, country of origin, and distance from home to a supermarket. The results highlight the importance of considering neighborhood characteristics in the development of prevention strategies for HIV and NCDs.