Is bone loss linked to chronic inflammation in antiretroviral-naive HIV-infected adults? A 48-week matched cohort study.

OBJECTIVE: Antiretroviral therapy (ART) has been implicated in bone loss in HIV. The role of inflammation and vitamin D is unclear and better investigated in ART-naive individuals. DESIGN AND METHODS: This is a 48-week, prospective cohort study to compare baseline and change in hip and spine bone mineral density (BMD) measured by dual-energy X-ray absorptiometry in HIV-infected, ART-naive adults and healthy controls matched by age, sex, and race. We also studied associations between bone loss and inflammation markers and plasma 25-hydroxyvitamin D [25(OH)D] using logistic regression. RESULTS: Forty-seven HIV-infected adults and 41 controls were included. Baseline 25(OH)D, BMD at total hip, trochanter, and spine, and prevalence of osteopenia and osteoporosis were similar between groups. In the HIV-infected group, total hip and trochanter, but not spine, BMD decreased over 48 weeks [hip -0.005 (-0.026-0.008) g/cm², P = 0.02 within group; trochanter -0.013 (-0.03-0.003), P < 0.01]. BMD did not change at any site within controls. The HIV-infected group was more likely to have bone loss at the trochanter (P = 0.03). This risk persisted after adjustment for age, sex, race, BMI, smoking, and hepatitis C (odds ratio 4, 95% confidence interval 1.2-15.8). In the HIV-infected group, higher interleukin-6 concentrations (P = 0.04) and Caucasian race (P < 0.01) were independently associated with progression to osteopenia or osteoporosis, but not 25(OH)D levels. CONCLUSION: BMD at the total hip and trochanter sites decreased in the HIV-infected, ART-naive adults, but not controls, over this 48-week study. Higher serum interleukin-6 concentrations were associated with progression to osteopenia or osteoporosis status in the HIV-infected group.