Atorvastatin treatment beneficially alters the lipoprotein profile and increases low-density lipoprotein particle diameter in patients with combined dyslipidemia and impaired fasting glucose/type 2 diabetes

Abstract

Diabetic dyslipidemia is featured by hypertriglyceridemia, low high-density lipoprotein (HDL) cholesterol levels, and elevated low-density lipoprotein (LDL) cholesterol commonly in the form of small, dense LDL particles. First-line treatment, fibrates versus statins or both, of dyslipidemia in diabetic patients has been the focus of debate. We investigated the potential hypolipidemic effects of atorvastatin, a 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor with good triglyceride lowering properties, in patients with combined dyslipidemia and evidence of impaired fasting glucose or type 2 diabetes. Twenty patients were recruited for the study, and after a 60-day wash out period, baseline measurements of lipoprotein parameters, LDL particle diameter, and apolipoprotein B (apoB) degradation fragments were obtained. The group was then randomized, in a double-blinded manner, into 2 subgroups. Group A received atorvastatin (80 mg) and group B received placebo daily for 60 days. After the first treatment period, all patients were reanalyzed for the above parameters. The treatment regime then crossed over for the second treatment period in which group A received placebo and group B received atorvastatin (80 mg) daily for 60 days. All parameters were remeasured at the end of the study. Treatment with atorvastatin resulted in a statistically significant reduction in total cholesterol (41%), LDL cholesterol (55%), triglycerides (TG) (32%), and apoB (40%). Mean LDL particle diameter significantly increased from 25.29 +/- 0.24 nm (small, dense LDL subclass) to 26.51 < 0.18 nm (intermediate LDL subclass) after treatment with atorvastatin (n = 20, P <.005). At baseline, LDL particles were predominantly found in the small, dense subclass; atorvastatin treatment resulted in a shift in the profile to the larger and more buoyant LDL subclass. Atorvastatin treatment did not produce consistent changes in the appearance of apoB degradation fragments in plasma. Our results suggest that atorvastatin beneficially alters the atherogenic lipid profile in these patients and significantly decreases the density of LDL particles produced resulting in a shift from small, dense LDL to more buoyant and less atherogenic particles.