Phase angle, arm fat mass, and arm fat area were predictive factors of muscle strength and muscle quality of people living with the human immunodeficiency virus: exploratory cross-sectional study

Abstract Background aims : Skeletal muscle mass and quality are compromised by fat infiltration, but gold standard assessments are often inaccessible. This study examined whether phase angle, arm fat mass, and arm fat area are associated with skeletal muscle strength and quality in adults living with HIV (PLWH). Methods : This is a cross-sectional study with a non-probabilistic sample composed of PLWH. Handgrip strength (HGS) was evaluated with a Jamar® dynamometer. Appendicular lean mass (ApLM) and arm fat mass (AFM) were assessed with Dual-energy x-ray absorptiometry (DXA). The phase angle (PhA) was evaluated with Bioelectrical Impedance. The arm fat area (AFA) was estimated with mid-upper arm circumference- and triceps skinfold thickness-derived equation. Muscle quality was assessed with the ratio of HGS and ApLM and HGS with body mass index (BMI). Results : Thirty-eight PLWH, 30 men (78.9%), and 8 women (21.1%) were evaluated. PhA was positively associated (b= 3.52; CI 95% 0.39 - 6.66) with HGS. The AFM was negatively associated with HGS (b= -3.64; CI 95% -5.69 to -1.60), MQI ApLM (b= -0.15; CI 95% -0.24 to -0.07), and MQI BMI (b= -0.22; CI 95% -0.30 to -0.13). Finally, AFA was negatively associated with HGS (-0.22; CI 95% -0.35 to -0.05), MQI ApLM (-0.009; CI 95% -0.01 to - 0.002), and MQI BMI (-0.01 CI 95% -0.02 to -0.002). Conclusion : Among people living with HIV, PhA, AFM, and AFA were predictors of muscle strength and quality.