Dexfenfluramine and heart-valve regurgitation in Chinese patients with type 2 diabetes

To assess whether valvular lesions are associated with the use of dexfenfluramine in Chinese patients with type 2 diabetes.

Case-control study.

Thirty-six obese Chinese patients with type 2 diabetes and a history of dexfenfluramine use during the period January 1992 and September 1997 were recruited into the study, while another 43 age- and sex-matched Chinese patients with type 2 diabetes were recruited as controls. The mean age for the cases was 44.1 years (standard deviation, 11.2 years; median, 42.5 years; range, 20-64 years). The 43 control subjects were age- and sex-matched, and had a mean age of 48.5 years (standard deviation, 10.9 years; median, 51.0 years; range, 16-63 years; P>0.05). The male-to-female ratio was confirmed as similar between the two groups (10:26 versus 12:31; P>0.05). All patients were clinically free from cardiovascular disease. Patients with a history of underlying valvular disease from any cause were excluded from the study. All patients underwent echocardiographic assessment, and the presence of any valvular lesions was documented.

The mean duration of dexfenfluramine use by the cases was 21.8 weeks (standard deviation, 29.0 weeks; median, 18.0 weeks; range, 1-160 weeks). Subjects with a history of dexfenfluramine use had higher rates of significant aortic regurgitation, tricuspid regurgitation of any severity, and of any valvular regurgitation, compared to controls (11.1% versus 0%, P<0.05; 30.6% versus 4.7%, P<0.01; and 61.1% versus 34.9%, P<0.05, respectively). Logistic stepwise regression analysis to predict the risk of valvular lesion was conducted, with age, sex, history of dexfenfluramine use, body mass index, waist-hip ratio, blood pressure, fasting plasma glucose, lipid profile, and duration of diabetes as independent variables. A history of dexfenfluramine use was the only significant parameter entered into the model (significant aortic regurgitation: beta=9.19, standard error=46.6, P<0.05; any tricuspid regurgitation: beta=2.76, standard error=10.8, P<0.05).

In Chinese patients with type 2 diabetes, a history of dexfenfluramine use is associated with heart-valve regurgitation, particularly aortic regurgitation.