Background: Disability and frailty are associated with osteoporosis, obesity, and sarcopenia. HIV-infected persons have early functional impairment, but the association between body composition and functional impairment is unknown.
Methods: HIV-1–infected participants on combination antiretroviral therapy with virologic suppression, aged 45–65 years, had standardized physical function measures. In a nested analysis, 30 low- and 48 high-functioning cases and controls were matched by age, gender, and time since HIV diagnosis. Bone mineral density, fat mass, and lean body mass were assessed by dual-energy x-ray absorptiometry. Odds ratios (ORs) with 95% confidence intervals were obtained from conditional logistic regression.
Results: Mean age was 53 years, mean CD4+ lymphocytes 598 cells per microliter, and 96% had plasma HIV-1 RNA <50 copies per milliliter. Low- and high-function subjects had similar CD4+ lymphocyte count and duration and type of antiretroviral therapy. Lower T scores at the hip [OR: 3.8 (1.1 to 12.5)] and lumbar spine [OR: 2.3 (1.1 to 4.5)] and lower lean body mass [OR: 1.1 (1.0 to 1.2)] were associated with significantly greater odds of low function (P ≤ 0.03). Lower insulin-like growth hormone [IGF-1; OR: 5.0 (1.4 to 20.0)] and IGF-1 binding protein-3 [OR: 3.3 (1.7 to 9.9)] increased the odds of low functional status (P ≤ 0.02). Fat mass and lower 25-OH vitamin D did not increase the odds of low functional status (P > 0.05).
Conclusions: Functional impairment in HIV-1–infected persons on successful antiretroviral therapy is associated with low muscle mass, low bone mineral density, and low IGF-1 and IGF-1 binding protein-3. These characteristics may be a manifestation of early “somatopause” in middle-aged HIV-infected adults.
Division of Infectious Diseases, Department of Medicine, Anschutz Medical Campus, University of Colorado, Aurora, CO.
Correspondence to: Kristine M. Erlandson, MD, Division of Infectious Diseases, Department of Medicine, Anschutz Medical Campus, University of Colorado, 12700 E 19th Avenue, Mail Stop B168; Aurora, CO 80045 (e-mail: email@example.com).
Supported by the National Institutes of Health (5UL1TR000154, P30 DK048520, and T32 AI007447-1), the Hartford Foundation Center of Excellence in Geriatric Medicine, and GlaxoSmithKline HIV Collaborative Investigator Research Award. Contents are the authors’ sole responsibility and do not necessarily represent official National Institutes of Health views.
The authors have no conflicts of interest to disclose.
Received November 20, 2012
Accepted January 24, 2013