Dialysis modality and survival: does the controversy live on?

Continued debate regarding the relative mortality risk for end-stage renal disease patients treated with either peritoneal dialysis or facility-based three times weekly conventional haemodialysis (CHD) stems from the absence of adequately powered randomized controlled trials, and the reliance on observational studies. These reports have yielded important trends, but also conflicting results. Here, we summarize the contemporary literature on survival comparisons between CHD and peritoneal dialysis, highlighting trends and important differences between studies.

Large observational studies have not conclusively shown an overall survival advantage of either dialysis modality. Studies have consistently shown an early survival advantage for peritoneal dialysis relative to CHD. New insights including accounting for selection bias and the use of central venous catheters as incident haemodialysis access may explain much of this apparent early mortality difference. The relative mortality risk of peritoneal dialysis versus haemodialysis may be decreasing in more contemporary cohorts. Older patients, diabetic patients, and those with comorbidities may have a relatively worse prognosis on peritoneal dialysis compared to CHD.

Overall, survival of incident end-stage renal disease patients is similar for CHD and peritoneal dialysis, but early survival differences may be driven by selection bias. Decisions regarding modality choice should be individualized, considering other important patient outcomes including quality of life. Whereas a future randomized controlled trial is ideally suited to address this question, practical limitations may continue to limit its development.