Longitudinal Analysis of Bone Density in Human Immunodeficiency Virus-Infected Women

Abstract

The objective of the study was to investigate change in bone mineral density (BMD) over time in HIV-infected women in comparison with healthy control subjects similar in age, race, and body mass index (BMI). This was a prospective cohort study. BMD was measured by dual-energy x-ray absorptiometry in 100 HIV-infected females and 100 healthy controls similar in age (41 +/- 1 vs. 41 +/- 1 yr, P = 0.57), BMI (26.1 +/- 0.5 vs. 27.2 +/- 0.4 kg/m(2), P = 0.12), and race (60 vs. 65% non-Caucasian, P = 0.47, HIV-infected vs. controls). Changes in BMD were determined every 6 months over 24 months. At baseline, HIV-infected subjects had lower BMD at the lumbar spine (1.01 +/- 0.01 vs. 1.07 +/- 0.01 g/cm(2), P = 0.001), hip (0.94 +/- 0.01 vs. 0.98 +/- 0.01 g/cm(2), P = 0.02), and femoral neck (0.83 +/- 0.01 vs. 0.87 +/- 0.01 g/cm(2), P = 0.02). Historical low weight, duration of nucleoside reverse transcriptase inhibitor use, and FSH were significantly associated with lumbar BMD, whereas duration of HIV, BMI, historical low weight, smoking pack-years, N-telopeptide of type 1 collagen, viral load, 25 hydroxyvitamin D, and osteocalcin were associated with hip BMD at baseline. In mixed model longitudinal analyses, BMD remained lower in HIV-infected subjects than in controls over 24 months of follow-up (P = 0.001 for the spine, P = 0.04 for the hip, and P = 0.02 for the femoral neck). These differences remained significant controlling for age, race, BMI, and menstrual function. In contrast, rates of change for the spine (P = 0.79), hip (P = 0.44), and femoral neck (P = 0.34) were not different between the HIV and control groups over 2 yr. In the HIV group, longitudinal changes in BMD were not associated with current protease inhibitor, nucleoside reverse transcriptase inhibitor, or non-nucleoside reverse transcriptase inhibitor use but were associated with CD4 count, weight, FSH, N-telopeptide of type 1 collagen, and baseline BMD. BMD is reduced at the spine, hip, and femoral neck among women with HIV in relationship to low weight, duration of HIV, smoking, and increased bone turnover. Over 2 yr of follow-up, BMD remained stable but lower in HIV-infected women, compared with control subjects.