Background: Studies comparing survival in hemodialysis (HD) or peritoneal dialysis (PD) patients reported controversial results, mainly during the first 2 years of treatment. Moreover, there is a significant geographic variation in the use of these modalities. We aimed to compare the survival of HD and PD patients using data from the Romanian Renal Registry.
Methods: In an intention-to-treat analysis using Kaplan-Meier and Cox proportional hazard (CPH) models, survival was compared between 8,252 incident HD patients and 1,000 incident PD patients treated between 2008 and 2011. The patients were followed from the dialysis initiation and stratified by modality on day 90. The time on dialysis was separated into four periods (3-12, 12-24, 24-36 and >36 months), and outcome comparisons were made.
Results: Mean survival time was 46.3 (44.9-47.6) months in PD group and 45.8 (45.3-46.3) months in HD group (p = 0.9, log-rank test). In the multivariate CPH models, age, diabetes-associated kidney disease (DM), primary renal disease and center size significantly influenced survival. In the first year of therapy, the mortality was higher in HD than in PD patients (HR = 1.34 (1.12-1.60), p = 0.001), while in the second and third year, HD patients survived better (HR = 0.69 (0.53-0.89), p = 0.005); HR = 0.56 (0.41-0.78), p = 0.001) and after 36 months, the survival difference was not statistically significant (HR = 0.63 (0.34-1.13), p = 0.1), respectively.
Conclusions: Despite the survival advantage for PD patients during the first year and that of HD in the next 2 years of dialysis, the overall survival in HD and PD patients was similar and was influenced by age, DM and center size.