Difference in Early Effects of Statin Therapy on Coronary and Forearm Flow Reserve in Postmenopausal Hypercholesterolemic Women

Abstract

The relationships between flow reserves in coronary and peripheral circulation and their modification by statin therapy have not been assessed in the same patients, especially females. To assess the effect of pravastatin on both circulation, in 20 postmenopausal female patients with hypercholesterolemia but a low probability of coronary artery disease, the forearm blood flow reserve (FBFR) using the plethysmographic method and coronary flow velocity reserve (CFVR) by Doppler echocardiography were measured before, 4 and 8 weeks after starting the pravastatin and/or diet therapy. At baseline, CFVR and FBFR had a positive linear correlation (r=0.63, p<0.01) while each of them had a negative linear correlation (r=-0.53 to -0.63, p<0.05 each) with total or LDL-cholesterol levels. Four weeks after starting the pravastatin therapy when the decrease in total cholesterol reached a plateau, FBFR increased (p<0.05) by 38+/-14%, whereas CFVR did not. Such an increase in FBFR by pravastatin was related to the degree of total or LDL-cholesterol lowering. In postmenopausal hypercholesterolemic women with a low probability of coronary artery disease, the cholesterol-lowering with pravastatin improved FBFR as early as 4 to 8 weeks after starting the therapy, whereas its effect on CFVR was unclear at that time.