The Ratio of Waist-to-Hip Circumference, Plasma Insulin Level, and Glucose Intolerance as Independent Predictors of the HDL2Cholesterol Level in Older Adults

High plasma levels of HDL2, a subfraction of high-density lipoprotein (HDL) cholesterol, are associated with a reduced risk of coronary heart disease. To investigate the characteristics related to HDL2 cholesterol levels, we measured lipoprotein levels and several metabolic and anthropometric variables in 146 healthy subjects (77 men and 69 women) in the seventh decade of life. The level of HDL2 cholesterol was inversely correlated with the ratio of the waist-to-hip circumference (r = -0.335 for men; r = -0.370 for women; P less than 0.01) and the plasma insulin level (r = -0.400 for men; r = -0.398 for women; P less than 0.001). In a multiple regression model including both sexes, 41 percent of the variance in the HDL2 level was explained by the combined effect of the waist-to-hip ratio (P less than 0.0001), the plasma insulin level (P = 0.0003), and the degree of glucose tolerance indicated by the integrated area under the plasma glucose curve after an oral glucose-tolerance test (P = 0.05). The body-mass index, total percentage of body fat, maximal oxygen uptake, diet, and sex were not significant predictors of the HDL2 level when added to this model, whereas the original variables remained significant predictors. The HDL2 cholesterol level in subjects at the 25th percentile for waist-to-hip ratio was 153 percent of that in subjects at the 75th percentile. We conclude that HDL2 levels are inversely correlated with truncal fat, plasma insulin levels, and the presence of glucose intolerance and are not independently associated with sex or total body fat.