Prevalence and risk factors for low bone mineral density in antiretroviral therapy-naive HIV-infected young men

Objective: We aimed to investigate the prevalence of low bone mineral density (BMD) and associated factors in antiretroviral therapy (ART)-naive HIV-infected young men.

Methods: In this cross-sectional study, dual-energy X-ray absorptiometry (DXA) was used to measure BMD. BMD at the lumbar spine, total hip and femoral neck sites was expressed as a Z-score (number of standard deviations away from the mean in an age, race and sex-matched reference population). Low BMD was defined as Z-scores≤-2 at any of the three sites. The prevalence of low BMD was evaluated at the lumbar spine, total hip and femoral neck sites, as were risk factors associated with Z-scores.

Results: The study cohort comprised 49 men, of whom 87.8% were white. Mean age was 31.6 (±7.7) years and mean BMI was 22.7 (±4.0)kg/m². Half of patients (51.0%) were current smokers. The prevalence of low BMD was 24.5% [95% CI, 13.3-38.9]. Low estradiol levels and low BMI were associated with low Z-scores at each skeletal site, whereas current smoking and high IGF1 levels were associated with low Z-scores at the lumbar spine site. Among the HIV-related factors, low CD4+ cell count was associated with low Z-scores at the lumbar spine site.

Conclusions: We observed a high prevalence of low BMD in our ART-naive cohort of young men. Risk factors associated with low Z-scores were those usually observed in HIV-infected individuals (low BMI, current smoking and CD4+ cell count) or linked to endocrine hormone levels (estradiol, IGF-1).