Meta-analysis: peritoneal membrane transport, mortality, and technique failure in peritoneal dialysis

Peritoneal membrane solute transport in peritoneal dialysis (PD) patients is assessed by the peritoneal equilibration test, which measures the ratio of creatinine in the dialysate to plasma after a standardized 4-h dwell (D/Pc). Patients then are classified as high, high-average, low-average, or low transporters on the basis of this result. A meta-analysis of observational studies was carried out to characterize the relationship between D/Pc and mortality and technique failure in patients who are on PD. Citations were identified in Medline by using a combination of Medical Subject Heading search terms and key words related to PD, peritoneal membrane permeability/transport, and mortality and technique failure. The table of contents of relevant journals and bibliographies of relevant citations were reviewed in duplicate. Twenty studies that met study criteria were identified. Nineteen studies were pooled to generate a summary mortality relative risk of 1.15 for every 0.1 increase in the D/Pc (95% confidence interval 1.07 to 1.23; P < 001). This result equated to an increased mortality risk of 21.9, 45.7, and 77.3% in low-average, high-average, and high transporters, respectively, as compared with patients with low transport status. Meta-regression analysis showed that the proportion of patients who were on continuous cycler PD within a study was inversely proportional to the mortality risk (P = 0.05). The pooled summary relative risk for death-censored technique failure was 1.18 (95% confidence interval 0.96 to 1.46; P = 0.12) for every 0.1 increase in the D/Pc. This meta-analysis demonstrates that a higher peritoneal membrane solute transport rate is associated with a higher mortality risk and a trend to higher technique failure.