In-center Automated Peritoneal Dialysis: Clinical Features, Practice Patterns, and Patient Survival From a 6-year Cohort Study in China

Abstract

Introduction: In-center automated peritoneal dialysis (APD) has been more frequently adopted in clinical practice for maintenance PD patients in China. For a better understanding of its clinical uptake, this retrospective study reviewed incident PD patients for a period of 6 years, investigating the practice pattern of in-center APD, factors associated with the use of in-center APD, and report on the patient survival compared to the non-users of APD among hospitalised PD patients. Methods: This was a cohort study of all incident PD patients who met the inclusion criteria from 2013/01/01 to 2018/09/30, and were followed until death, cessation of PD, loss to follow-up, or 2018/12/31. Clinical characteristics, patient outcomes, and detailed data on APD sessions were recorded. We used time-dependent Cox model to estimate the variables associated with the initiation of in-center APD, and marginal structural model through inverse probability weighting to adjust for time-varying APD use on the causal pathway to all-cause mortality. Results: A total of 651 subjects over 17501 patient-months were enrolled. Of these, 633 (97.2%) PD patients were hospitalised at least once during follow-up, and 369 (56.7%) received in-center APD at a certain point, and the timing of APD use during the first 3 months, first year and first 2 years since PD inception were 14.8%, 45.4% and 74.8%, respectively. A total of 12553 in-center APD sessions were recorded, where 85.9% used 4 bags of 5L-exchanges per prescription. Time-dependent Cox model showed that diabetes (hazard ratio [HR], 1.39, 95% confidence interval [CI], 1.09−1.76), urine output (HR 0.80, 95% CI 0.70-0.92), serum albumin (HR 0.84, 95%CI 0.72-0.99), hemoglobin (HR 0.88, 95%CI 0.77-0.99), and Ca×P (HR 1.19, 95%CI 1.06-1.35) were significantly associated with in-center APD use. Among all hospitalised PD patients, the estimated hazard ratio corresponding to the marginal causal effect of in-center APD use on all-cause mortality is 0.13 (95% CI 0.05–0.31, P<0.001). Significant survival benefit (adjusted-HR 0.56, 95%CI 0.33-0.95) associated with starting APD after the first PD year was observed among in-center APD users. Conclusions: In-center APD is used intensively during the first 2 years of PD and is associated with certain clinical features. Over all a significant survival benefit of in-center APD use was observed.