Relaxin Is an Independent Risk Factor Predicting Death in Male Patients With End-Stage Kidney Disease

Abstract
Background— Patients with end-stage kidney disease (ESKD) have a reduced life expectancy mainly as the result of cardiovascular diseases. Relaxin has been implicated in the pathogenesis of cardiovascular diseases. We analyzed the impact of relaxin on death in patients with ESKD. Methods and Results— Patients (n =245; 122 women, 123 men) on long-term hemodialysis were followed for 1140 days for death. Blood samples for analysis of relaxin, C-reactive protein, Troponin T, cholesterol, HDL, brain natriuretic peptide, and albumin were taken at study entry. Survival was compared by the Kaplan-Meier method and Cox regression analysis. One hundred seven patients died during the observation period; 66 died of cardiovascular diseases and 28 died of infectious diseases. Elevated serum relaxin concentrations (greater than median) predicted death in male but not in female patients with ESKD: All-cause death (men: relative risk, 2.63; 95% CI, 1.34 to 5.12; P =0.005; women: relative risk, 0.671; 95% CI, 0.33 to 1.35; P =0.262) and cardiovascular death (men: relative risk, 2.95; 95% CI, 1.20 to 7.21; P =0.018; women: relative risk, 0.639; 95% CI, 0.26 to 1.56; P =0.324). Conclusions— Relaxin is an independent risk factor predicting death in male patients with ESKD on chronic hemodialysis.