Combination Therapy with Renin-Angiotensin System Blockers and Vitamin D Receptor Activators for Predialysis Patients Is Associated with the Incidence of Cardiovascular Events after Dialysis Initiation: A Multicenter Nonrandomized Prospective Cohort Study

Background: Several human studies reported that the combined use of renin-angiotensin system blockers (RASBs) and vitamin D receptor activators (VDRAs) resulted in decreased urinary protein excretion. However, it is unknown whether this combination therapy influences the incidence of cardiovascular (CV) events in dialysis patients. Methods: The study was a multicenter nonrandomized prospective cohort analysis including 1,518 patients. Patients were classified into 4 groups based on medications prescribed before dialysis initiation: those who did not receive RASBs or oral VDRAs (N group), those receiving only RASBs, those receiving only VDRAs, and those receiving a combination of RASBs and VDRAs (RD group). CV events after dialysis initiation were compared using the log-rank test. Factors contributing to the incidence of CV events were examined using multivariate Cox proportional hazard regression analysis. Results: Significant differences were observed in the incidence of CV events and all-cause mortality between the 4 groups (p = 0.021 and p = 0.001, respectively). Cox proportional hazard analysis revealed that the incidence of CV events was significantly lower in the RD group than in the N group (hazard ratio [HR] = 0.65, 95% confidence interval [CI]: 0.50-0.86, p = 0.002). Multivariate analysis revealed that the incidence of CV events was significantly lower in the RD group than in the N group (HR = 0.66, 95% CI: 0.47-0.93, p = 0.016). Conclusion: Combination therapy with RASBs and VDRAs in patients before dialysis initiation was associated with a reduction in CV events during maintenance dialysis.