Incidence and risk factors of peritoneal dialysis-related peritonitis in elderly patients: A retrospective clinical study

Background: This study was to analyze the incidence, risk factors, and clinical outcomes of peritonitis in elderly continuous ambulatory peritoneal dialysis (CAPD) patients. Methods: Incident patients undergone CAPD from 1 January 2006 to 30 June 2015 in our center were enrolled and divided into aged < 65 years and ≥ 65 years groups. Risk factors were evaluated using a logistic regression model, and outcome comparison was evaluated using a Cox proportional model. Results: Among 1953 patients, 111(33.2%) in elderly ( n = 334) and 470 (29.0%) in younger ( n = 1619) developed at least one episode of peritonitis. Comparing with younger patients, elderly ones had a higher peritonitis rate (0.203 vs. 0.145 episodes/patient-year, p < 0.05). The multivariate Cox regression showed that advanced age (hazard ratio (HR) = 1.06, 95% confidence interval (CI) = 1.01–1.11, p = 0.015), assistant-assisted peritoneal dialysis (PD; HR = 2.64, 95% CI = 1.23–5.64, p = 0.012), higher body mass index (BMI; HR = 1.11, 95% CI = 1.02–1.20, p = 0.010), and low serum albumin level (HR = 0.94, 95% CI = 0.90–0.98, p = 0.004) were associated with increased peritonitis risk in elderly patients. Compared with younger ones with peritonitis, elderly patients had an approximately fourfold increased risk of peritonitis-related mortality (odd ratio (OR) = 3.57, 95% CI = 1.38–9.28, p = 0.009). During the cohort, peritonitis was the risk factor associated with technique failure (HR = 3.19, 95% CI = 2.33–4.39, p < 0.001) in younger patient but not in the elderly population (HR = 1.82, 95% CI = 0.84–3.94, p = 0.132). Conclusions: Elderly PD patients had higher prevalence for peritonitis and peritonitis-related mortality. Advanced age, assistant-assisted PD, a higher BMI, and lower serum albumin level were independently associated with the first episode of peritonitis in elderly patients. However, peritonitis was not the predictor of death-censored technique failure in elderly ones.