Effect of hypertension and antihypertensive medications on residual renal function in children treated with chronic peritoneal dialysis

Purpose: To evaluate the effect of hypertension (HTN) and antihypertensive medications (AHM) on residual renal function (RRF) in children on CAPD and APD. Material/methods: We retrospectively evaluated underlying kidney disease, systolic and diastolic blood pressure (SBP/DBP), presence and control of HTN (SBP/DBP >= 95th percentile), AHM, RRF (daily diuresis, residual glomerular filtration rate [rGFR]), biochemical parameters, BMI Z-score, and dialysis parameters during 12-month follow-up in 87 children (38 CAPD, 49 APD) aged 10.22 +/- 4.31 years. The rate of RRF loss was expressed as absolute and relative [%] reduction. Results: At baseline, HTN was found in 74.7% patients (CAPD/APD: 84.2%/67.3%, P = 0.06), most commonly in HUS and least frequently in CAKUT. The proportion of CAPD/APD patients with poorly controlled HTN was 70.0%/63.3% (P = 0.50). Relative daily diuresis loss in children with uncontrolled HTN was higher (P = 0.017) compared to children with SBP/DBP <95th percentile. No effect of AHM on the rate of RRF loss was found. In multivariate analysis, absolute daily diuresis loss was related to baseline diuresis (beta = -0.30, P < 0.001) and proteinuria (beta = -0.31, P = 0.004); absolute rGFR loss to baseline rGFR ( beta = -0.73, P < 0.001) and glucose load after 12 months (beta = -0.36, P = 0.02); relative daily diuresis loss to mean BMI Z-score (beta = -0.44, P = 0.04); and relative rGFR to baseline rGFR (beta = -0.37, P < 0.001) and SBP percentile (beta= -0.21, P = 0.045). Conclusions: 1. Maintaining blood pressure <95th percentile helps preserve RRF in children with ESRD treated with peritoneal dialysis. 2. Risk factors for rapid RRF loss in children on CAPD/APD include elevated SBP, high baseline diuresis/rGFR, proteinuria, and high glucose load in the dialysis fluid. (C) 2014 Medical University of Bialystok. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.