Waist circumference, waist to hip ratio, and body mass index in the diagnosis of metabolic syndrome in Nigerian subjects

Metabolic syndrome is the commonest controllable precursor of cardiovascular and end stage renal diseases. While central obesity is recognized universally as its strongest component, there is the need for an accurate and affordable tool to screen for the presence of metabolic syndrome in every community. The easiest and cheapest measures of obesity are the body mass index (BMI), waist circumference (WC) and waist to hip ratio (WHR). This study investigated the potential of BMI, WHR and WC in diagnosis of metabolic syndrome (MS) in Nigerian subjects.This cross sectional study involved three hundred and thirty eight apparently healthy adult Nigerians recruited within the University College Hospital and its environs were evaluated for the features of metabolic syndrome using the World Health Organisation and the NCEP ATP 111 criteria. BMI, WC, WHR, Blood Pressure, Fasting Lipid Profile and Fasting Plasma Glucose were measured in each participant. Correlation between BMI, WC, WHR and Blood Pressure, Fasting Lipid Profile and Fasting Plasma Glucose which are other components of MS was determined and empirical Receiver Operating Characteristics (ROC) analysis was used to evaluate each of them as predictors of MS. The prevalence of MS in the studied population was significantly higher (36.7%) using NCEP definition than (23.7%) using WHO definition (p<0.05). By both definitions, this prevalence was higher in females than in males (p<0.05). WC was positively correlated with FPG and TG (r=0.560 and 0.436 respectively; P=0.000) in the NCEP category while WC was positively correlated with FPG, SBP and DBP (r=0.254, 0.480, and 0.490 respectively; P>0.05) in the WHO category. ROC Analysis shows WC having the highest AUC (0.785) hence diagnoses MS more accurately than both BMI (0.733) and WHR (0.783) using in the NCEP ATP 111 criteria. The highest Area Under Curve (AUC) was observed in WHR (0.837) followed by WC (0.799) in the WHO category. Both WC and WHR are shown to be good predictors of the presence of MS. It will be appropriate to incorporate WC measurement into routine general physical examination in our clinics.