Background: Non-controlled studies have noted a high prevalence of valvular regurgitation in patients with Chinese herb nephropathy; most of these patients had taken appetite suppressants. We aimed to determine the prevalence of valvular regurgitation and the role of appetite suppressants in patients with Chinese herb nephropathy.
Methods: This case-controlled echocardiographic study included 40 patients with end-stage renal failure due to Chinese herb nephropathy and 37 age-matched controls with end-stage renal disease due to nephropathy of other origin. Quantification of cumulative doses of appetite suppressants was performed.
Results: Aortic regurgitation was detected in 52.5% of patients with Chinese herb nephropathy, 72+/-1 months after stopping appetite suppressants, and in 21.6% of controls (P=0.009). No difference was found in the incidence of mitral or tricuspid regurgitation. A history of slimming medication was the only significant determinant for aortic regurgitation (P=0.009). Higher cumulative doses of Chinese herbs, (dex)fenfluramine and diethylpropion were observed in patients with Chinese herb nephropathy with, when compared to those without, aortic regurgitation. The dose-response relationship between the cumulative dose of drugs and the presence of aortic regurgitation was significant for fenfluramine only (chi-square=5.16, P=0.024).
Conclusions: Six years after stopping appetite suppressants, aortic regurgitation remains highly prevalent among patients with end-stage Chinese herb nephropathy. The dose-related association with fenfluramine intake strongly confirms a determinant pathogenic role of anorectic drugs.