Low Baseline CD4+Count Is Associated With Greater Bone Mineral Density Loss After Antiretroviral Therapy Initiation

Background. Bone mineral density (BMD) decreases 2%–6% in the 2 years after antiretroviral therapy (ART) initiation. Pre-ART immune deficiency and early immune recovery may contribute to this loss. Methods. We pooled data from 3 studies of ART initiation in treatment-naive patients in which serial whole-body dual-energy X-ray absorptiometry scans were performed. We used linear regression to evaluate effects of baseline CD4 + and 16-week CD4 + change (both absolute and relative) on 96-week total BMD change from baseline. We performed multivariable linear regression to assess associations between baseline variables of age, sex, race/ethnicity, body mass index (BMI), hepatitis C status, parent study, human immunodeficiency virus type 1 (HIV-1) RNA level, and assignment to a protease inhibitor (PI)– or tenofovir-containing regimen on 96-week total BMD change. Results. The included 796 subjects had mean 96-week total BMD loss of 2.0%. In multivariable analysis, baseline CD4 + cell count was significantly associated with 96-week BMD loss; individuals with baseline CD4 +