Geographic and facility-level variation in the use of peritoneal dialysis in Canada: a cohort study.

Background: Peritoneal dialysis is associated with similar survival and similar improvement in quality of life and is less costly compared with in-centre hemodialysis. We examined facility and geographic variation in the use of peritoneal dialysis in Canada.
Methods: We analyzed data from the Canadian Organ Replacement Register for the period January 2001 to December 2010. We identified patients for whom peritoneal dialysis was the primary modality at 90 days after initiation of dialysis. We used multilevel models to evaluate variation in use of peritoneal dialysis by facility and geographic region.
Results: We analyzed data for 31 778 incident dialysis patients at 56 facilities in 13 geographic regions across Canada. Use of peritoneal dialysis at 90 days varied considerably across geographic regions (range 19.8%-36.1%) and declined over time, from 28.8% in 2001 to 22.5% in 2010. After adjustment for case mix and facility-level quality indicators, 9.3% and 3.4% of the variability was attributable to facility and geographic factors, respectively. In adjusted models, there was a substantial difference between geographic regions with the lowest and highest peritoneal dialysis use (odds ratio for high use 1.51, 95% confidence interval [CI] 1.33-1.73 v. odds ratio for low use 0.69, 95% CI 0.60-0.79).
Interpretation: In Canada, substantial variability in the use of peritoneal dialysis attributable to facility and geographic region was not explained by differences in patient case mix. An opportunity exists to optimize use of this cost-effective therapy through changes in policy and standardization of criteria for initiation of peritoneal dialysis.