Influencing factors for residual kidney function in incident peritoneal dialysis patients: a systematic review and meta-analysis

Residual kidney function (RKF) impacts patients’ survival rate and quality of life when undergoing peritoneal dialysis (PD). This meta-analysis was conducted to systematically identify risk and protective factors associated with RKF decline and loss. We searched three English and one Chinese databases from inception to January 31, 2023, for cohort and cross-sectional studies exploring factors associated with RKF decline or loss. The random effects model was employed to aggregate risk estimates and 95% confidence intervals (CIs) from multivariate analysis. Sensitivity and subgroup analyses were performed to explore the heterogeneity among the studies. Twenty-seven studies comprising 13549 individuals and 14 factors were included in the meta-analysis. Based on the meta-analysis results, risk factors involving male gender (hazard ratio (HR) 1.689, 95%CI 1.385–2.061), greater body mass index (BMI) (odds ratio (OR) 1.081, 95% confidence interval (CI) 1.029–1.135), higher systolic blood pressure (SBP) (HR 1.014, 95%CI 1.005–1.024), diabetes mellitus (DM) (HR_{RKF loss} 1.873, 95%CI 1.475–2.378), DM (OR_{RKF decline} 1.906, 95%CI 1.262–2.879), peritonitis (relative ratio (RR) 2.291, 95%CI 1.633–3.213), proteinuria (OR 1.223, 95%CI 1.117–1.338), and elevated serum phosphorus (RR 2.655, 95%CI 1.679–4.201) significantly contributed to the risk of RKF decline and loss in PD patients. Conversely, older age (HR 0.968, 95%CI 0.956–0.981), higher serum albumin (OR 0.834, 95%CI 0.720–0.966), weekly Kt/V urea (HR 0.414, 95%CI 0.248–0.690), baseline urine volume (UV) (HR 0.791, 95%CI 0.639–0.979), baseline RKF (HR 0.795, 95%CI 0.739–0.857) exhibited protective effects. However, diuretics use, automatic peritoneal dialysis (APD) modality and baseline RKF did not significantly impact RKF decline. Patients with male gender, greater BMI, higher SBP, DM, peritonitis, proteinuria, and elevated serum phosphorus might have a higher risk of RKF decline and loss. In contrast, older age, higher serum albumin, weekly Kt/V urea, baseline UV, and baseline RKF might protect against RKF deterioration.