High-density lipoprotein and glycosylated hemoglobin in nondiabetic individuals.

We investigated associations of high-density-lipoprotein (HDL) cholesterol, apolipoprotein A-I, and triglyceride levels with hemoglobin A1 (HbA1) and insulin levels in nondiabetic subjects (137 women and 111 men). In women, HDL cholesterol, apolipoprotein A-I, and log-triglyceride values were significantly correlated with those of HbA1 and log-fasting insulin. These univariate associations persisted when age and Quetelet's index were included as covariates in multiple regression analyses. Conversely, univariate associations of HDL cholesterol and log-triglyceride levels with Quetelet's index were diminished by the addition of insulin values to multivariate models. Insulin levels and Quetelet's index were highly correlated. Although there were weaker associations in men, apolipoprotein A-I and HbA1 values were inversely related. These data suggest that HDL cholesterol and apolipoprotein A-I levels are closely linked to glucose metabolism in nondiabetic individuals.