Prevalence and determinants of valvulopathy in patients treated with dexfenfluramine

Background-Valve regurgitation has been associated with dexfenfluramine, bu t its prevalence and severity are uncertain. Additional factors that may co ntribute to valve regurgitation in patients exposed to this drug are poorly understood. Methods and Results-Echocardiography was performed on subjects recruited fr om 26 prescribing sites in 15 states. The total sample of 412 subjects incl uded 172 dexfenfluramine patients and 172 unexposed controls matched for ag e, sex, and body mass index and 68 unmatched subjects meeting the same entr y criteria (51 dexfenfluramine patients and 17 controls). Mean treatment du ration was 6.9 months; mean interval from treatment discontinuation to echo cardiogram was 8.5 months. Each echocardiogram was interpreted independentl y by 3 echocardiographers, FDA-grade regurgitation (at least mild aortic re gurgitation or at least moderate mitral regurgitation) was significantly mo re frequent in dexfenfluramine patients (7.6% versus 2.1% for controls; P=0 .01; odds ratio, 3.82). This difference was primarily due to more frequent mild aortic regurgitation in dexfenfluramine patients (6.3% versus 1.6% in controls; P<0.02; odds ratio, 4.15). No differences were found in sclerosis or mobility for either the aortic or mitral valve. Factors independently r elated to FDA-grade regurgitation or any grade of aortic regurgitation were older age, higher diastolic blood pressure at the time of echocardiography , and shorter time from drug discontinuation to echocardiogram. Conclusions-Dexfenfluramine use is associated with an increase in the preva lence of abnormal valve regurgitation. Age and blood pressure may also affe ct the prevalence of regurgitation. Dexfenfluramine-related valve regurgita tion may regress after drug discontinuation.