Hemodialysis and Peritoneal Dialysis

Abstract

Various studies indicate that fair comparisons of mortality rates between hemodialysis (HD) patients and peritoneal dialysis (PD) patients are difficult because of differences in patient characteristics, because of nonconstant relative risks of death (RR), and because the survival times of patients who switch treatment modalities can be censored in different ways. The differences in mortality rates between HD and PD patients were investigated in an analysis in which these potential sources of bias were taken into account. The Netherlands Cooperative Study on the Adequacy of Dialysis is a multicenter, prospective, observational, cohort study in which new patients with ESRD are monitored until transplantation or death. A multivariate Cox regression analysis was used to analyze the mortality data according to treatment modality (HD, n = 742; PD, n = 480). No statistically significant differences in adjusted mortality rates between HD and PD patients were observed during the first 2 yr of dialysis. In the years thereafter, increases in mortality rates for PD patients and resulting decreases in RR in favor of HD were observed (e.g., months 24 to 36, adjusted RR, 0.53; 95% confidence interval, 0.31 to 0.91). This tendency was observed especially among patients >/=60 yr of age and was not influenced by the censoring strategy. These results suggest that long-term use of PD, especially among elderly patients, is associated with increases in mortality rates. Further analyses are required to determine the potential role of dialysis adequacy in the observed long-term differences in mortality rates between HD and PD patients and to establish the possible survival benefits for PD patients who switch to HD in time.

Dialysis Modality after Renal Transplant Failure

“…The demonstrated early benefit of PD is similar to that reported in well-designed observational studies, such as one study using the ANZDATA registry (7) and another from the Netherlands Cooperative Study on the Adequacy of Dialysis (8). However, those studies also identified worse survival after 1 -2 years for patients on PD, similar to the multivariate results in the current Perl analysis, but at odds with the propensity-matched results.…”

Mortality by Dialysis Modality among Patients Who Have End-Stage Renal Disease and Are Awaiting Renal Transplantation

“…However, although the association between modality and outcomes was not present among the cohort overall, patients whose baseline BMI were Ն26 kg/m 2 had increased mortality associated with the selection of PD versus HD. Previous studies both agree (5,9,16,17,24,26,27) and disagree (1,2,4,7,12,14,23,25,28) with these results; however, the concordance and discordance of results must be interpreted with considerations of the differences in patient populations and analytic techniques. Although a randomized, controlled trial is necessary to solve the differential findings in observational studies, an initial attempt at a trial was not successful (20).…”

“…Overweight patients, in particular, may have more difficulty achieving adequate dialysis with the gradual loss of residual renal function over time. The increased risk associated with PD over time supports this potential theory (9,17,25). Whereas the ADEMEX trial suggested that variations in peritoneal clearance do not affect long-term outcomes (29), underdialysis of overweight hemodialysis patients has been associated with poorer outcomes (30).…”

“…O utcomes among patients who are on hemodialysis (HD) and peritoneal dialysis (PD) have been compared in numerous conflicting studies (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17). Disparate findings likely are a result of various sources of bias that threaten the validity of observational studies.…”

Obesity and Mortality Risk among Younger Dialysis Patients

“…Differences in outcome between these two patient groups have been suggested, although the determinants of dialysis modality are largely nonmedical. Two large studies among HD and PD patients showed little difference in risk for death during 2-5 years of follow-up (42,43). Second, we used BMI as a proxy for obesity, but BMI only indirectly reflects the risk stemming from the metabolic effects of an increased fat mass (44).…”