Impact of pioglitazone on coronary endothelial function in non-diabetic patients with coronary artery disease

Objective  Pioglitazone has been shown to exert multiple antiatherosclerotic actions independent from its glycemic effects. We studied the hypothesis that pioglitazone improves coronary endothelial dysfunction in non-diabetic patients with coronary artery disease (CAD) in a randomized, placebo-controlled, double-blind trial. Methods  Fifty non-diabetic patients with CAD were randomized to 6 months treatment with pioglitazone 30 mg daily or placebo. Coronary endothelial function was tested at baseline and after 6 months with intracoronary infusion of adenosine, acetylcholine (0.072; 0.72; 7.2, and 36 μg/min), glyceroltrinitrate, and cold pressor test (CPT). The primary endpoint was the mean effect of treatment compared with placebo on acetylcholine-induced coronary vascular response for all acetylcholine dosages, based on percent change in luminal area measured by quantitative coronary angiography. Results  There was no difference in baseline coronary endothelial function. The primary endpoint was significantly different between the groups with a 1.8% ± 2.0% increase in luminal area between baseline and follow-up with pioglitazone and a 7.6% ± 2.4% decrease in the placebo group (P < 0.008). At follow-up, there was a trend for a difference in CPT (P = 0.057). No difference was observed regarding intracoronary glyceroltrinitrate or adenosine. Conclusions  Pioglitazone treatment in non-diabetic patients with CAD was associated with a significantly better coronary endothelial function compared to placebo.