Hyperinsulinemia predicts multiple atherogenic changes in lipoproteins in elderly subjects.

Several studies have shown that hyperinsulinemia and insulin resistance are associated with high triglyceride and low high-density lipoprotein (HDL) cholesterol levels. However, previous studies have been cross-sectional, and thus the presence of hyperinsulinemia or insulin resistance could be a consequence of the underlying lipid disorder instead of its cause. Therefore, we examined the relation of fasting insulin level measured in a cross-sectional study in nondiabetic subjects 65 to 74 years old (n = 881) to the risk of developing lipid disorders 3.5 years later. The incidence of the following lipid abnormalities was calculated: hypertriglyceridemia (n = 49/732, incident cases/subjects free of the particular disorder at baseline), high low-density lipoprotein (LDL) cholesterol level (n = 43/696), low HDL cholesterol level (n = 33/708), high apolipoprotein (apo) B level (n = 72/699), low apoAI level (n = 47/711), low serum LDL cholesterol/serum apoB ratio (n = 55/685), and low serum HDL cholesterol/serum apoAI ratio (n = 48/707). Baseline insulin level was not significantly associated with the development of high LDL cholesterol or low HDL cholesterol levels. Baseline insulin was associated with the development of hypertriglyceridemia (odds ratio OR, 1.64; 95% confidence interval CI, 1.12 to 2.40; P = .011), high apoB (OR, 1.54; 95% CI, 1.13 to 2.10; P = .006), low apoAI (OR, 1.72; 95% CI, 1.22 to 2.42; P = .002), low LDL cholesterol/apoB ratio (OR, 1.99; 95% CI, 1.36 to 2.90; P < .001), and low HDL cholesterol/apoAI ratio (OR, 1.93; 95% CI, 1.34 to 2.79; P < .001).(ABSTRACT TRUNCATED AT 250 WORDS)