Differential associations of cardiovascular disease risk factors with relative wealth in urban-dwelling South Africans

Background To examine the associations of cardiovascular disease risk factors (CVDRF) with wealth, defined by the asset index, in 25- to 74-year-old black Africans in Cape Town. Methods Assets, including consumer durable goods, and CVDRF were determined in a randomly selected cross-sectional sample. A principal component analysis of the pooled data, based on assets that defined wealth, was used to develop an asset index. Ordinal logistic regression analyses assessed the independent associations of CVDRF with wealth tertiles. Results Among the 1099 participants, the least poor compared with the poorest tertile had significantly higher prevalence of diabetes (16.3 versus 9.6%), hypercholesterolaemia (33.9 versus 21.4%), obesity (45.4 versus 26.3%) and fat intake ≥30% of diet (44.2 versus 29.3%). Daily smoking was highest in the poorest (35.8%) versus the least poor (26.4%). Psychosocial stress (low sense of coherence or locus of control) was significantly higher in poorer participants. In the regression analyses, wealth was associated with male gender [odds ratio (OR): 1.89, 95% confidence interval (CI): 1.37-2.60], urbanization (OR: 1.02, 95% CI: 1.01-1.02), high fat intake, obesity and hypercholesterolaemia. Daily smoking, problematic alcohol use (OR: 0.70, 95% CI: 0.52-0.94) and psychosocial stress were inversely related to wealth. Conclusions Differential distribution of CVDRF by wealth mandates incorporating equity components when developing tailored interventions.