Derivation of anthropometric cut-off levels to define CVD risk in Sri Lankan adults

Abstract

Obesity is associated with increased cardiovascular risk. Anthropometric cut-off values derived for Caucasians may not be applicable to other populations. The main objective of the present study was to derive population-specific anthropometric cut-off values to define high CVD risk for Sri Lankan adults. A nationally representative sample of 4474 non-institutionalised adults aged ≥18 years was analysed. Cut-off values to provide optimum sensitivity and specificity were derived using receiver-operating characteristic curve analysis. BMI, waist circumference (WC), waist-to-hip ratio (WHR), blood pressure and overnight fasting venous blood samples were collected to measure glucose, HDL-cholesterol and TAG. An oral glucose tolerance test was also performed. The results suggested that the age-adjusted BMI, WC and WHR were significantly associated with all cardiovascular risk factors (P<0·001). Cut-off values for BMI, WC and WHR for males were 20·7kg/m2, 76·5cm and 0·89, respectively. The respective values for females were 22·0kg/m2, 76·3cm and 0·85. The common cut-off value for BMI for males and females was 21·5kg/m2. Similarly, WC and WHR cut-off values for both males and females were 76·3cm and 0·87, respectively. The Asian and Caucasian anthropometric cut-off levels showed lower sensitivity and higher false negative percentage compared with newly derived cut-off levels. In conclusion, BMI, WC and WHR were all associated with increased CVD risk. We propose the following anthropometric cut-off points to determine high CVD risk level for Sri Lankan adults: BMI≥21·5kg/m2, WC≥76cm and WHR≥0·85 (women) and 0·90 (men).