Received November 12, 2007
Accepted on July 17, 2008

CLINICAL EPIDEMIOLOGY

Relationship between Dialysis Modality and Mortality

Stephen P. McDonald ^*1, Mark R. Marshall ^*, David W. Johnson ^*, and Kevan R. Polkinghorne ^*||

*ANZDATA Registry and Renal Unit, Queen Elizabeth Hospital and Disciplines of Medicine and Public Health, University of Adelaide, Adelaide, Department of Nephrology, University of Queensland at Princess Alexandra Hospital, Brisbane, and ||Department of Nephrology, Monash Medical Centre and Faculty of Medicine, Monash University, Melbourne, Australia; and Renal Medicine, Middlemore Hospital and School of Medicine, University of Auckland, Auckland, New Zealand

¹ To whom correspondence should be addressed. E-mail: stephenm{at}anzdata.org.au.

	Abstract

Mortality differences between peritoneal dialysis (PD) and hemodialysis (HD) are widely debated. In this study, mortality was compared between patients treated with PD and HD (including home HD) using data from 27,015 patients in the Australia and New Zealand Dialysis and Transplant Registry, 25,287 of whom were still receiving PD or HD 90 d after entry into the registry. Overall mortality rates were significantly lower during the 90- to 365-d period among those being treated with PD at day 90 (adjusted hazard ratio [HR] 0.89; 95% confidence interval [CI] 0.81 to 0.99]; P < 0.001). This effect, however, varied in direction and size with the presence of comorbidities: Younger patients without comorbidities had a mortality advantage with PD treatment, but other groups did not. After 12 mo, the use of PD at day 90 was associated with significantly increased mortality (adjusted HR 1.33; 95% CI 1.24 to 1.42; P < 0.001). In a supplementary as-treated analysis, PD treatment was associated with lower mortality during the first 90 d (adjusted HR 0.67; 95% CI 0.56 to 0.81; P < 0.001). These data suggest that the effect of dialysis modality on survival for an individual depends on time, age, and presence of comorbidities. Treatment with PD may be advantageous initially but may be associated with higher mortality after 12 mo.