Raloxifene and endothelial function in healthy postmenopausal women.

Objective: The purpose of this study was to determine the effects of raloxifene on endothelial function in healthy, postmenopausal women.

Study Design: This was a randomized, double-blind, placebo-controlled crossover trial. Subjects (n = 19; mean age, 61 years) underwent endothelial function testing at baseline and after treatment with placebo or raloxifene (60 mg per day for 6 weeks).

Results: Brachial artery diameter change (flow-mediated dilation) increased 5.0% with placebo and 8.56% with raloxifene (SE = 1.83, P =.03) in response to a hyperemic stimulus; an adjustment of this response for a variation in stimulus intensity resulted in greater discrimination (P =.009). The ratio of area under the curve response to area under the curve reference with the use of laser Doppler measures was 1.18 for placebo and 1.28 for raloxifene (P =.05). Flow-mediated dilation and area under the curve ratio correlated significantly (r = 0.33, P =.04).

Conclusion: Treatment with raloxifene enhanced endothelial-mediated dilation in brachial arteries and digital vessels in healthy, postmenopausal women. A potential mechanism for a cardioprotective effect of raloxifene is suggested and warrants further study.