Effects of lovastatin and gemfibrozil in subjects with high ratios of total cholesterol to high-density lipoprotein cholesterol

Insulin resistance is associated with hypertriglyceridemia, low serum high- density lipoprotein cholesterol (HDL-C) concentrations and high serum total cholesterol (TC) to HDL-C ratios. Several reports have demonstrated that e ither lovastatin or gemfibrozil may favourably lower serum lipid, concentra tions. However, their effects on insulin sensitivity are unknown. The prima ry aim of this study was to compare the effects of lovastatin and gemfibroz il on insulin sensitivity and serum leptin concentrations in subjects with high TC/HDL-C ratios. We enrolled 25 nondiabetic patients, similar in terms of age and weight with TC/HDL-C ratios greater than 5. Thirteen subjects w ere treated with lovastatin 20 mfi per da!, anti 12 received gemfibrozil 30 0 mg twice per day. Plasma lipids, glucose, and leptin were measured, and a 75-g oral glucose tolerance test (OGTT) and a modified insulin suppression test were performed before and after 3 months of treatment. The study show ed the mean plasma TC, low-density lipoprotein cholesterol (LDL-C) concentr ations, and TC/HDL-C ratio were significantly reduced in the lovastatin-tre ated group, but no obvious effects on plasma triglyceride (TG) and HDL-C we re rioted. In the gemfibrozil group, plasma TG and HDL-C were markedly lowe red, but no significantly different effects ill other plasma lipids were fo und. Gemfibrozil did not affect steady-state plasma glucose (SSPG) concentr ations, whereas lovastatin significantly! increased SSPG concentrations. Ne ither drug affected the serum leptin concentration during the OGTT. We conc lude that lovastatin significantly lowers plasma TC and LDL-C ratio, and TC /HDL-C concentrations and and adversely affects insulin sensitivity, while gemfibrozil markedly reduces plasma TG concentrations without altering insu lin sensitivity in subjects with high TC/HDL-C ratios.