Fracture and Bone Mineral Density in HIV+ Patients Recently Started on Antiretroviral Therapy (ART)

In a group of HIV-positive patients under observation since their first exposure to ART or monitored off of ART, BMD changes over one year will be determined. For each subject, the investigators will also determine associations between changes in BMD and 1) ART initiation, 2) cumulative viremia (measured by copy-years viremia), and 3) inflammation (evaluated through the measurement of interleukin-6 {IL-6}, tumor necrosis factor alpha {TNF-a}, high-sensitivity c-reactive protein {hsCRP}). Hypotheses: BMD will decrease less in persons initiated on ART than those monitored off of ART, after excluding those subjects treated with tenofovir. BMD will decrease most significantly in HIV-positive subjects with the highest levels of cumulative viremia. HIV-positive persons with highest cumulative viremia will have the highest levels of inflammation, as measured by pro-inflammatory cytokines. Additionally, the investigators will evaluate fracture incidence in a 5% National Medicare sample and fracture association with the use of varying ART medications among dual-eligible persons in Medicare and Medicaid datasets. Hypotheses: Fracture incidence will be greater in HIV-positive subjects compared to HIV-negative subjects.Fracture incidence will be greatest in subjects with the shortest duration of ART exposure.