Phase angle is a better indicator of nutritional status than body mass index in patients on hemodialysis

Abstract

Introduction: Multi-frequency bio-impedance analysis (BIA) accurately evaluates body composition. Objective: To assess nutritional status and its relationship with body mass index (BMI) or with BIA-obtained phase angle in patients with end-stage renal disease (ESRD) on hemodialysis. Method: BMI, BIA and dialysis malnutrition score (DMS) were assessed in 99 patients on hemodialysis (43.6 ± 17.2 years of age, 58.8% males). Multivariate linear regression analysis was used to determine BMI and phase angle independent associations with DMS. Results: Malnutrition risk (DMS > 13) showed a gradual increase among patients with normal BMI and phase angle (44.4%), low BMI (45.8%), low phase angle (64.0%), and in those with both parameters at abnormal ranges (68.0%). The phase angle was the only variable that was independently associated with patient nutritional status (standardized coefficient beta −0.372, p < 0.001), accounting for 13.8% of DMS variation. Conclusion: Phase angle is inversely and independently associated with malnutrition risk in patients with ESRD, which suggests that BIA-assessed body composition might be better than BMI in the clinical assessment of patients with ESRD.