Measures of obesity and accepted cardio-metabolic disease risk factors from a peri-urban female farm working population in South Africa

Background: Cardiovascular diseases (CVD) remains a primary cause of (central) obesity-associated mortality among African populations. Measures of adiposity are reported as prevalence’s in a South African (SA) female farm working population at risk for cardio-and metabolic disease related to body mass index, (BMI), waist-to-hip ratio (W:H), waist circumference (WC) and visceral adiposity index (VAI), biochemical and metabolic blood parameters.Methods: A cross-section of female farm workers (n=120) from the Boland region in SA between the ages 20-60 years were recruited and classified according to different anthropometric indices including BMI, W:H, WC and the VAI, and subsequently divided into normal- and at risk groups for each index. Blood samples were analysed for inflammatory markers, serum insulin, glucose and a full lipid profile.Results: Prevalence’s and significant differences for the different adiposity measures between normal and overweight groups were: (BMI: 25.8% - 74.2%; p<0.0001); (W:H: 57.5% - 42.5%; p<0.0001); (WC: 42.0% vs 58.3%; p<0.0001); and (VAI: 48.3% vs 51.7%; p<0.0001). Systolic blood pressure (p<0.01) and diastolic blood pressure (p=0.03) were different within the BMI grouping, as well as VAT% (p<0.001) and SAT% (p<0.01). Differences were reported for body mass, BMI, WC and VAI within the W:H and WC groupings. Systolic (p=0.04) and diastolic blood pressure (p=0.0009) were different in the WC grouping. Metabolic healthy and unhealthy women showed differences in BMI (p<0.05); W:H (p<0.0001); WC (p<0.0001). Systolic and diastolic blood pressure were different between metabolic healthy (p<0.05) and unhealthy women (p=0.0005). The inflammatory cytokines were similarly elevated in the normal and obese groups TNFα; (p<0.0001); IL-6; (p<0.01), MCP-1; (p=0.0001), and resistin; (p<0.0001). For the W:H, IL-6 (p<0.01) and blood glucose (p=0.006) were different. The WC grouping showed differences in resistin (p<0.0001), MCP-1 (p<0.0001, blood glucose (p<0.01, and insulin (p=0.0002). For metabolic healthy vs unhealthy women, resistin (p<0.0001); MCP-1 (p=0.0007); blood glucose (p<0.01) and insulin (p<0.05) were different.Conclusion: Women suffering from obesity showed a higher pro-inflammatory profile and higher risk for cardio-metabolic disease using the BMI as a measure of adiposity compared to WC, W:H and VAI.