Comparison of clinical assessment and multifrequency bioimpedance analysis as methods of estimating volume status in peritoneal dialysis patients - A single-center experience

Clinical assessment (CA) is frequently used for the evaluation of volume status in peritoneal dialysis (PD) patients despite its subjectivity. Multiple-frequency bioelectrical impedance analysis (MF-BIA) is objective, accurate, and quick, proving to be a promising technique for measuring volume status. The aim of this study was to assess volume status in PD patients using CA and MF-BIA and to compare results. Incident PD patients were prospectively analyzed between January 1, 2014, and January 1, 2016, at the Clinical Hospital Center of -Rijeka, Croatia. Volume status measurements were performed once a month for 6 consecutive months. The presence of symptoms and signs associated with hyper- or hypovolemia were detected by CA. Euvolemia was defined as a symptom-free state or up to 2 symptoms maximum. Patients lacking up to 1.2 L of volume or with up to 1.2 L in excess were considered euvolemic, as measured by MF-BIA. A total of 45 PD patients were analyzed; 51% were men, 27% were diabetic, the mean age was 52 ± 26 years, and PD duration was 11.5 ± 6.5 months. In comparison to MF-BIA, CA showed a significant difference in detected hypervolemia between baseline and follow-up (p = 0.708 vs. p = 0.01, respectively) and among all measurements (p < 0.01). Contrary to CA, volume status measured by MF-BIA correlated significantly with systolic and diastolic blood pressure (R = 0.29; p ≤ 0.01 and R = 0.26; p ≤ 0.01, respectively). CA showed low sensitivity (0.24) and high specificity (0.92) in detecting hypervolemia. MF-BIA is an effective, objective, and safe method for assessing volume status in PD patients. Longitudinal monitoring of body composition changes - including hydration state - leading to adequate therapeutic intervention is a promising and potential application of MF-BIA along with CA. .