Effects of clofibrate on glucose tolerance, serum insulin, serum lipoproteins and plasma fibrinogen

Abstract

The effects of clofibrate therapy were studied in fifty year old, weight-stable, free-living men not on specific dietary treatment. The patients had been selected because of hyperlipidaemia and/or glucose intolerance found at a health screening survey. The study lasted for four months and was double-blind and cross-over in design. The results showed no effect of clofibrate treatment on glucose tolerance, as measured by an intravenous glucose tolerance test, neither in the entire group (t=0.90, 2p>0.05, n=21) nor in a subgroup (t=−0.71, 2p>0.05, n=10) with glucose intolerance on screening. Fasting blood glucose was significantly decreased (t=3.71, 2p<0.01) in the subgroup (n=8) with fasting blood glucose greater than 100 mg/100 ml during the placebo period. There was, however, a significant (t=4.00, 2p<0.001) reduction in fasting serum(S-)insulin concentration during clofibrate therapy. The reduction was correlated with relative body weight (r=0.59, 2p<0.01). Elevated S-lipoproteins were decreased by clofibrate therapy, S-low density lipoprotein cholesterol concentrations by 20 per cent and S-very low density lipoprotein triglyceride concentrations by 52 per cent. Significant falls in plasma fibrinogen concentration (t=4.57, 2p<0.001) and erythrocyte sedimentation rate (t=2.48, 2p<0.025) also occured, which were not correlated to the other effects reported.