Associação do ângulo de fase com a sarcopenia e seus componentes em idosos

Abstract

Introduction: Phase angle (PhA) is a marker of "cellular health" and has been associated with muscle mass and strength in several populations. However, it is still not well known the association of PhA with sarcopenia and its components in physically active older adults. Objective: Associate PhA with sarcopenia and its components in physically active older adults. Methods: A cross-sectional study was performed with 118 physically active older adults (79.7% of women). PhA and muscle mass were assessed by bioelectrical impedance. Muscle strength was measured by handgrip strength (HGS) using a manual dynamometer. Functional capacity was evaluated by 4-meters walking test. Sarcopenia was diagnosed according to the European Consensus on Definition and Diagnosis of Sarcopenia. Participants were evaluated according to the PhA tercile. The individuals were divided into two groups: 1st vs. 2nd and 3rd terciles, according to sex. The individuals in the first tercile were considered having low PhA, being the values <6.5º and <5.7º for men and women, respectively. Results: PhA was not associated with sarcopenia (OR = 1.90 (0.698-5.177)), muscle mass index (OR = 1.75 (0.620-4.937)), HGS (OR = 1.98 (0.171 - 22.998)) and walking speed (OR = 0.77 (0.230-2.572)). In addition, PhA was also not associated with sarcopenia and its components when women were evaluated separately. PhA was not correlated with muscle mass (r = -0.01, p = 0.960), muscle mass index (r = -0.05; p = 0.619), HGS (r = 0.16; p = 0.098) and walking speed (r = 0.08, p = 0.417) in total sample. However, when women were analyzed separately, PhA showed a weak correlation with walking speed (r = 0.24, p = 0.023) and, after multiple linear regression analysis, PhA was able to predict the variations in walking speed by 3.9%. Conclusion: PhA was not associated with sarcopenia and its components in physically active older adults. In addition, although PhA was correlated with walking speed test in older women, the biological meaning of this association is questionable since the power of prediction was low (3.9%).