HMG CoA reductase inhibitors are related to improved systemic endothelial function in coronary artery disease

Inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase (st atins) may enhance vascular endothelial function independent of their chole sterol lowering effect. To test this hypothesis, we surveyed two groups of patients (age 55 +/- 7, mean +/- SD) with coronary artery disease that were matched for age, blood pressure and serum lipid levels. Group 1 comprised 23 men without lipid-lowering medication and Group 2 included 22 patients w ith ongoing HMG CoA reductase inhibitor medication. Flow-mediated (endothel ium-dependent) arterial dilatation (FMD) and nitrate-mediated (smooth muscl e dependent) dilatation (NMD) were measured in the brachial artery using hi gh resolution ultrasound. FMD was considerably higher in group 2 (4.3 +/- 2 .6 vs. 2.6 +/- 2.8%; P < 0.05). In multivariate regression model, statin us e was the only significant (P < 0.05) predictor of FMD. In all subjects, FM D correlated with statin dose (P < 0.05 for trend). NMD was non-significant ly higher in group 2 (11.4 +/- 5.0 vs. 9.0 +/- 4.2%, P = 0.08). We conclude that patients with established coronary artery disease on HMG CoA reductas e inhibitor therapy have better vascular endothelial function than similar patients without the medication. These data provide further support for the idea that HMG CoA reductase inhibitors enhance endothelial function indepe ndent of their lipid-lowering effects. This may suggest that these drugs co uld be beneficial in secondary prevention of coronary artery disease regard less of the serum cholesterol concentration. (C) 1999 Elsevier Science Irel and Ltd. All rights reserved.