Body Composition, Soluble Markers of Inflammation, and Bone Mineral Density in Antiretroviral Therapy-Naive HIV-1-Infected Individuals

Objective: To determine the association among bone mineral density (BMD), inflammatory markers, and alterations in fat and lean mass in untreated HIV-infected individuals. Design: Cross-sectional analysis of antiretroviral therapy-naive persons enrolled into a randomized clinical trial. Methods: Dual-energy x-ray absorptiometry for BMD and lean and fat mass and a laboratory assessment were performed. Soluble biomarkers included adipocytokines (leptin and adiponectin), inflammatory markers (high-sensitivity C-reactive protein and interleukin 6), and markers related to bone metabolism [osteoprotegerin (OPG)], receptor activator of nuclear factor kappa kB ligand. BMD at the lumbar spine, total hip, and femoral neck was expressed as a Z score (number of standard deviations away from age-, race-, and sex-matched reference population). Results: Three hundred thirty-one subjects had a median (Q(1), Q(3)) age of 36 (28, 45) years, were 89% men, and 44% white. The prevalence of low BMD (Z score <= -2 at any of the 3 sites) was 10%. No associations were detected between Z scores and high-sensitivity C-reactive protein, interleukin 6, or receptor activator of nuclear factor kappa B ligand (P >= 0.1). In a linear model adjusting for age, gender, race, and total fat mass, lower lumbar spine Z scores were associated with lower total lean mass, higher serum adiponectin, and lower OPG. Results at the total hip or femoral neck were similar. Conclusions: Among antiretroviral therapy-naive HIV-infected individuals, lower BMD was associated with lower lean mass, higher adiponectin, and lower OPG, but not HIV disease variables or any of the inflammatory markers. These findings may have implications for bone metabolism in untreated HIV, in which hypoadiponectinemia and higher OPG may mitigate bone loss.