The Effect of Salsalate Therapy on Endothelial Function in a Broad Range of Subjects

BACKGROUND Inflammation is fundamental to the development of atherosclerosis. We examined the effect of anti-inflammatory doses of salicylate on endothelium-dependent vasodilation, a biomarker of cardiovascular risk, in a broad range of subjects. METHODS AND RESULTS We performed a randomized, double-blind, placebo-controlled crossover trial evaluating the effects of 4 weeks of high-dose salsalate (disalicylate) therapy on endothelium-dependent flow-mediated and endothelium-independent vasodilation. Fifty-eight subjects, including 17 with metabolic syndrome, 13 with atherosclerosis, and 28 healthy controls, were studied. Among all subjects, endothelium-dependent flow-mediated vasodilation decreased after salsalate compared with placebo therapy (P=0.01), whereas nitroglycerin-mediated, endothelium-independent vasodilation was unchanged (P=0.97). Endothelium-dependent flow-mediated vasodilation after salsalate therapy was impaired compared with placebo therapy in subjects with therapeutic salicylate levels (n=31, P<0.02) but not in subjects with subtherapeutic levels (P>0.2). CONCLUSIONS Salsalate therapy, particularly when therapeutic salicylate levels are achieved, impairs endothelium-dependent vasodilation in a broad range of subjects. These data raise concern about the possible deleterious effects of anti-inflammatory doses of salsalate on cardiovascular risk. CLINICAL TRIAL REGISTRATION URL www.clinicaltrials.gov. Unique Identifiers: NCT00760019 and NCT00762827.