Predicational ability of phase angle on protein energy wasting in kidney disease patients with renal replacement therapy: A cross‐sectional study

Abstract

Objective To investigate the ability of phase angle (PA) and body composition for predicting protein energy wasting (PEW) in renal replacement therapy (RRT) patients. Methods Renal replacement therapy (RRT) patients were enrolled in this study. Body composition was measured by direct segmental multi‐frequency biolectrical impedance analysis method (DSM‐BIA); phase angle (PA), fat‐free mass (FFM), fat mass (FM), mid‐arm circumference (MAC), WC (waist circumference), and ECW/TBW (extracellular water/total body water) were obtained. Biochemicals (serum albumin, triglyceride, and cholesterol) were tested. PEW patients were classified according to ISRNM (The International Society of Renal Nutrition and Metabolism) criteria. Cutoff value of PA and related variables was calculated by ROC analysis. The ability of body composition variables as indicators to predict PEW was evaluated. Results Sixty‐four patients were enrolled in this study. Thirty‐three patients (52.6%) were males, and forty (62.5%) patients were diagnosed with PEW. The ROC curve showed that the optimal cutoff values of PA, FFMI (fat‐free mass index), MAC, WC, and BMI for PEW risk were 4.45°, 16.71, 29.7 cm, 86.4 cm, and 21.1 kg/m2, respectively. These indicators showed significant association with PEW; meanwhile, the PA and MAC can be used as the predictors for PEW with OR 6.333 (95% CI, 1.956–20.505) and 3.267 (95% CI, 1.136–9.394), respectively. Both groups have a lower BUN/Cr ratio (<20). Conclusion In the RRT patients, over than 60% patients were diagnosed with PEW. PA, MAC, and other body composition can be used as the independent indicators for predicting PEW in renal replacement therapy kidney disease patients.

Bioelectrical Impedance Analysis Derived-Phase Angle as a Pragmatic Tool to Detect Protein Energy Wasting among Multi-Ethnic Hemodialysis Patients

“…In this study, PhA was found to be an independent predictor of PEW in HD patients (adjOR: 0.308, p = 0.001). As expected, patients with PEW had a lower PhA compared to their non-PEW counterparts [11,15].…”

“…This relationship could be attenuated owing to regression dilution bias because of day-to-day variation in dietary intake [55,56]. However, this did not confiscate the discriminative ability of PhA to detect PEW among HD patients in both current and previous studies [12,15].…”

“…Despite the PhA disparity across patients' characteristics in different populations [11][12][13]15], the external validity of PhA in detecting PEW among the HD population has been extended to a multi ethnicity population. In this study, PhA was found to be an independent predictor of PEW in HD patients (adjOR: 0.308, p = 0.001).…”

“…As such, a bioelectrical impedance analysis (BIA)-derived phase angle (PhA) has been emerging as a valid proxy of PEW by assessing the nutritional state at the cellular level [11][12][13][14][15]. PhA is derived from the arc tangent value of the ratio of reactance (Xc) to resistance (R) [16].…”

“…Mounting evidence has supported the use of PhA as a prognostic indicator for various clinical conditions (i.e., cancer, cirrhosis, surgery, and frailty) [19,[22][23][24]. Although PhA has also been proposed as a rapid, inexpensive, and non-invasive method to detect PEW among dialysis patients in several countries (i.e., China, Japan, Mexico, and Spain) [11][12][13][14][15], the extrapolation of their findings is questionable due to the variation in body composition across ethnicities [25] as evidenced by the inconsistent cut-offs identified (ranging from 3.7 • to 4.64 • ) [11][12][13][14][15]. In addition, the absence of gender-specific cut-offs for PhA might diminish its diagnostic accuracy for PEW detection.…”