The waist-to-hip ratio corrected for body mass index is related to serum triglycerides and high-density lipoprotein cholesterol but not to parameters of glucose metabolism in healthy premenopausal women

Summary

Android obesity is associated with metabolic disorders, but the causality of this relationship remains unclear. We investigated the association of body mass index (BMI) and waist-to-hip ratio (WHR) with hormones, glucose tolerance, insulin sensitivity, serum lipoproteins, and the serum activity of hepatic enzymes in 40 healthy premenopausal women (BMI 19.2–46.1, mean 32.6±1.3 kg/M²; WHR 0.68-1.01, mean 0.82±0.02). BMI correlated with WHR (r=0.52, P<0.01). After correction for WHR, BMI was negatively correlated with high-density lipoprotein cholesterol and positively with total and very low density lipoprotein triglycerides, insulin sensitivity, blood glucose, serum insulin and glucagon. After adjustment for BMI, WHR was significantly associated with high-density lipoprotein cholesterol, total and very low density lipoprotein triglycerides, and the serum activities of hepatic enzymes but not with insulin sensitivity, blood glucose, serum insulin, or glucagon. According to these results, body fat distribution assessed by WHR is related to hypertriglyceridemia and alterations in hepatic function such as a fatty liver. WHR is not primarily related to glucose metabolism in healthy premenopausal women without preexisting metabolic disorders such as glucose intolerance. Therefore the observable association between android obesity and manifest impairment in glucose metabolism may develop secondarily during persisting hyperinsulinemia, which itself is primarily related to obesity. Thus an android body fat distribution may rather be an accompanying feature than a predictor of impaired glucose tolerance and insulin resistance.