Associations of Muscle Density and Area With Coronary Artery Plaque and Physical Function.

Objective: Skeletal muscle quality and mass are important for maintaining physical function during advancing age. We leveraged baseline data from Randomized Trial to Prevent Vascular Events in HIV (REPRIEVE) to evaluate whether paraspinal muscle density and muscle area are associated with cardiac or physical function outcomes in people with HIV (PWH).

Methods: REPRIEVE is a double-blind randomized trial evaluating the effect of pitavastatin for primary prevention of major adverse cardiovascular events in PWH. This cross-sectional analysis focuses on participants who underwent coronary computed tomography at baseline. Lower thoracic paraspinal muscle density (Hounsfield units [HU]) and area (cm 2 ) were assessed on noncontrast computed tomography.

Results: Of 805 PWH, 708 had paraspinal muscle measurements. The median age was 51 years and 17% were natal female patients. The median muscle density was 41 HU (male) and 30 HU (female); area 13.2 cm 2 /m (male) and 9.9 cm 2 /m (female). In adjusted analyses, greater density (less fat) was associated with a lower prevalence of any coronary artery plaque, coronary artery calcium score >0, and high plaque burden ( P = 0.06); area was not associated with plaque measures. Among 139 patients with physical function measures, greater area (but not density) was associated with better performance on a short physical performance battery and grip strength.

Conclusions: Among PWH, greater paraspinal muscle density was associated with a lower prevalence of coronary artery disease while greater area was associated with better physical performance. Whether changes in density or area are associated with changes in CAD or physical performance will be evaluated through longitudinal analyses in REPRIEVE.