Fluvastatin treatment and withdrawal: effects on endothelial function

Fluvastatin lowers lipids and protects endothelial function. This study investigated how 2 preparations of fluvastatin would affect endothelial function after treatment and early after its discontinuation. Twenty-seven patients received 80 mg extended-release fluvastatin every day, 40 mg immediate-release fluvastatin twice a day, or placebo for 5 weeks. Fasting lipids and flow-mediated dilation were measured at baseline and after each treatment period. In 21 patients, flow-mediated vasodilation was also measured 24 hours after discontinuation of therapy. Both forms of fluvastatin improved flow-mediated vasodilation (extended release: P < .037 and immediate release: P < .001). However, this improvement occurred preferentially in patients with low baseline flow-mediated vasodilation (<5%). Twenty-four hours after treatment discontinuation, the flow-mediated vasodilation deteriorated again to baseline (extended release and immediate release: P < .001). Fluvastatin improved flow-mediated vasodilation only in patients with low baseline values. Twenty-four hours after discontinuation, the flow-mediated vasodilation deteriorated again, surprisingly irrespective of prior improvement.