Decreased limb muscle and increased central adiposity are associated with 5-year all-cause mortality in HIV infection.

BACKGROUND: Unintentional loss of weight and muscle due to aging and disease has been associated with increased mortality. Wasting and weight loss occur in HIV infection even in the modern era of effective antiretroviral therapy.
METHODS: We determined the association of MRI-measured regional and total skeletal muscle and adipose tissue with 5-year, all-cause mortality in 922 HIV-infected persons in the study of Fat Redistribution and Metabolic Change in HIV Infection (FRAM).
RESULTS: After 5 years of follow-up, HIV-infected participants with arm skeletal muscle in the lowest tertile had a mortality rate of 23%, compared with 11 and 8% for those in the middle and highest tertiles. After multivariable adjustment for demographics, cardiovascular risk factors, HIV-related factors, inflammatory markers, and renal disease, we found that lower arm skeletal muscle, lower leg skeletal muscle and higher visceral adipose tissue (VAT) were each independently associated with increased mortality. Those in the lowest tertile of arm or leg skeletal muscle had higher odds of death [arm: odds ratio (OR) = 2.0, 95% confidence interval (CI) 0.96-4.0; leg: OR = 2.4, 95% CI 1.2-4.8] compared with the highest respective tertiles. Those in the highest tertile of VAT had 2.1-fold higher odds of death (95% CI 1.1-4.0) compared with the lowest VAT tertile.
CONCLUSION: Lower muscle mass and central adiposity appear to be important risk factors for mortality in HIV-infected individuals. A substantial proportion of this risk may be unrecognized because of the current reliance on body mass index in clinical practice.