Association of dialysis modality and cardiovascular mortality in incident dialysis patients

Background and objectives: The aim of the investigation presented here was to compare the rates, causes, and timing of cardiovascular (CV) death in incident peritoneal dialysis (PD) and hemodialysis (HD) patients. Design, setting, participants, & measurements: The study included all adult Australian and New Zealand patients commencing dialysis between January 1, 1997 and December 31, 2007. Rates of and times to CV death were compared by incident rate ratios, cumulative incidence, and multivariable Cox proportional hazards model analyses. Dialysis modality was included in the model as a time-varying covariate, and a competing risks approach was used to obtain cause-specific hazard ratios. Results: Of the 24,587 patients who commenced dialysis (first treatment PD n =6521; HD n = 18,066) during the study, 5669 (21%) died from CV causes [PD 2044 (28%) versus HD 3625 (21%)]. The incidence rates of CV mortality in PD and HD patients were 9.99 and 7.96 per 100 patient-years, respectively (incidence rate ratio PD versus HD, 1.25; 95% confidence interval 1.12 to 1.32). PD was consistently associated with an increased hazard of CV death compared with HD after 1 yr of treatment. This increased risk in PD patients was largely accounted for by an increased risk of death due to myocardial infarction. Conclusions: Dialysis modality is significantly associated with the risk, causes, and timing of CV death experienced by ESRD patients in Australia and New Zealand.