Hypercholesterolemia in non-insulin-dependent diabetes mellitus: different effect of simvastatin on VLDL and LDL cholesterol levels.

Non-insulin-dependent diabetes mellitus (NIDDM) is often characterized by an increase in VLDL-triglyceride, VLDL-cholesterol, LDL-cholesterol and a reduction in HDL-cholesterol. HMG-CoA reductase inhibitors significantly lower cholesterol rates and have an indirect effect on the LDL receptor. We measured the effect of simvastatin in 28 hypercholesterolemic subjects, including 14 with NIDDM in good metabolic control (HbAIc 7.8% +/- 1.3%). A 24-week treatment with 10 mg/day (weeks 1-4), 20 mg/day (weeks 5-8) and 40 mg/day (weeks 9-24) simvastatin revealed different responses in diabetic and non-diabetic patients. Total cholesterol, LDL-cholesterol and apo B decreased significantly in both groups (less in the diabetics), whereas only NIDDM patients displayed a significant reduction in VLDL-cholesterol and VLDL-apo B. In the non-diabetics, the reduction in plasma cholesterol was mainly confined to the LDL fraction (276 +/- 65 vs. 132 +/- 28 mg/dl), whereas a significant fall in VLDL-cholesterol (45 +/- 19 vs. 21 +/- 10 mg/dl) was more evident in the NIDDM patients. Simvastatin also influenced plasma apo B levels (221 +/- 33 vs 134 +/- 23 mg/dl in non-diabetics and 182 +/- 44 vs. 134 +/- 30 mg/dl in diabetics). Significant reduction of apo B, LDL-apo B (205 +/- 39 vs. 128 +/- 23 mg/dl) in the non-diabetics and VLDL-apo B (16 +/- 5 vs. 9 +/- 2 mg/dl) in the diabetics, indicates that the VLDL are primarily concerned when statins are administered in NIDDM.(ABSTRACT TRUNCATED AT 250 WORDS)