Muscle Quality and Physical Function in Men With and Without HIV.

Area of Science:

• Gerontology
• HIV/AIDS Research
• Skeletal Muscle Physiology

Background:

• People with HIV (PWH) exhibit accelerated physical decline compared to people without HIV (PWoH), even with antiretroviral therapy.
• Skeletal muscle health is crucial for maintaining physical function and quality of life.

Purpose of the Study:

• To compare skeletal muscle density and area between PWH and PWoH.
• To investigate the relationship between skeletal muscle characteristics and physical function in both groups.

Main Methods:

• Quantitative computed tomography (CT) scans of the L4-L5 spinal region and thigh were used to assess muscle groups.
• Exploratory factor analysis summarized aggregated muscle measures.
• Multivariable linear regression models with generalized estimating equations analyzed longitudinal associations between muscle measures and physical function (gait speed, grip strength).

Main Results:

• Two factors emerged: Factor 1 represented muscle density (32.5% variance), and Factor 2 represented muscle area (23.4% variance).
• Higher aggregated muscle density was significantly associated with increased gait speed (0.028 m/s per unit increase).
• Both aggregated muscle density (1.88 kg increase) and area (1.60 kg increase) were associated with increased grip strength.

Conclusions:

• Aggregated skeletal muscle density and area measurements are significantly associated with physical function in both PWH and PWoH.
• These findings highlight the importance of interventions targeting skeletal muscle health for promoting healthy aging in individuals living with or without HIV.