Prevalence and Risk Factors for Bone Mineral Density Changes in Antiretroviral Therapy-Naive Human Immunodeficiency Virus-Infected Adults: A Chinese Cohort Study
Human immunodeficiency virus (HIV) infection and its associated complications, including bone mineral density (BMD) alterations, have become a growing concern in China. With approximately 1.25 million people living with HIV/AIDS in China by 2018 and rising annual infection rates, understanding the health impacts of HIV in untreated populations is critical. This study investigated the prevalence, anatomical distribution, and risk factors for reduced BMD in 156 antiretroviral therapy (ART)-naive HIV-infected adults, providing insights into early bone demineralization patterns and clinical interventions.
Study Design and Population
This retrospective cross-sectional study was conducted at Beijing Ditan Hospital, Capital Medical University, between July and December 2018. Eligible participants were ART-naive adults aged ≥18 years, confirmed HIV-positive, and free from conditions influencing BMD, such as hyperthyroidism, diabetes, menopause, corticosteroid use, or prior calcium/vitamin D supplementation. Exclusion criteria included opportunistic infections, hormonal disorders, or comorbidities affecting bone metabolism.
Demographic, clinical, and laboratory data were collected, including age, smoking and alcohol use, exercise habits, BMI, CD4+ T cell counts, HIV viral load (VL), and co-infections (hepatitis B, syphilis). BMD was measured using dual X-ray absorptiometry (DXA) scans at the lumbar spine (L1–L4) and bilateral hips (femoral neck, trochanter, and intertrochanteric regions). Reduced BMD was classified using World Health Organization (WHO) criteria: osteopenia (T/Z score between −1.01 and −2.49) and osteoporosis (T/Z score ≤−2.50). Statistical analyses included logistic regression to identify risk factors and Spearman correlations to assess variable relationships.
Key Findings on Prevalence and Anatomical Distribution
Of the 156 participants (all male, median age 28 years), 53.2% (83/156) exhibited reduced BMD, comprising 48.7% (76/156) with osteopenia and 4.5% (7/156) with osteoporosis. Reduced BMD affected multiple sites in 39.1% of patients: 19.2% (30/156) had two affected sites, and 19.9% (31/156) had all three sites involved.
Lumbar Spine Vulnerability
The lumbar spine had the highest prevalence of bone loss (49.4%, 77/156). Among individual vertebrae, L1 showed the most significant reduction (60.9%, 95/156), followed by L2 (53.2%), L4 (52.6%), and L3 (45.5%). These findings highlight the lumbar spine, particularly the L1 segment, as a critical site for early BMD monitoring.
Hip Region Asymmetry
The left hip showed higher osteopenia prevalence (32.7%, 51/156) than the right hip (24.4%, 38/156). Within the hip compartments, the trochanter was most affected: 46.2% (72/156) of left trochanters and 28.8% (45/156) of right trochanters had reduced BMD, compared to lower rates in the femoral neck (left: 26.9%, right: 18.6%) and intertrochanteric regions (left: 15.4%, right: 13.5%). This asymmetry may reflect biomechanical differences in weight-bearing patterns, with dominant limbs (typically right-sided) experiencing less bone loss due to higher mechanical stress.
BMI as a Critical Risk Factor
Low BMI emerged as the strongest predictor of reduced BMD. Participants with BMI <18.5 kg/m² had an 81.8% (9/11) prevalence of osteopenia/osteoporosis, compared to 59.0% (59/100) in the normal BMI group (18.5–23.9 kg/m²) and 33.3% (15/45) in overweight/obese groups (BMI ≥24.0 kg/m²). Binary logistic regression confirmed that BMI <18.5 kg/m² significantly increased the risk of bone loss (OR = 39.743; 95% CI: 3.234–488.399; P = 0.004).
Spearman correlations reinforced this relationship: BMI positively correlated with BMD at the right hip (r = 0.335), left hip (r = 0.327), and lumbar spine (r = 0.311) (P < 0.001 for all). These results align with global studies linking low BMI to bone demineralization in HIV populations, emphasizing nutritional status as a modifiable risk factor.
Secondary Findings and Absence of Traditional Risk Factors
Contrary to prior studies, traditional risk factors like age, smoking, alcohol use, CD4+ T cell counts, and HIV VL showed no significant association with BMD. For example:
- CD4+ T cells: Median counts were comparable between normal (330 cells/mm³) and low BMD groups (307 cells/mm³).
- HIV VL: No differences were observed across low (<1,000 copies/mL), moderate (1,000–100,000 copies/mL), or high (≥100,000 copies/mL) VL categories.
- Co-infections: Hepatitis B (5.8%) and syphilis (18.6%) co-infections did not correlate with BMD changes.
This suggests that chronic HIV infection itself, rather than immunodeficiency severity or viral replication, may drive bone loss in untreated patients.
Clinical Implications and Recommendations
This study underscores the high prevalence of osteopenia in ART-naive HIV patients, with nearly half exhibiting bone demineralization. The lumbar spine and left hip trochanter are early and frequent sites of bone loss, warranting prioritized screening. Low BMI, a readily modifiable factor, should be addressed through nutritional support to mitigate fracture risks.
For clinical practice:
- Routine BMD Screening: Implement DXA scans at ART initiation, focusing on lumbar spine (L1–L4) and hip trochanters.
- BMI Monitoring: Incorporate BMI assessments into HIV care protocols, with interventions for underweight patients.
- Patient Education: Advise weight-bearing exercise to enhance mechanical loading, particularly in non-dominant limbs.
Limitations and Future Directions
The study’s single-center design and all-male cohort limit generalizability to women and other populations. Future research should explore:
- Longitudinal BMD changes after ART initiation, particularly with tenofovir-based regimens.
- Mechanisms linking HIV to bone demineralization, including inflammatory markers and hormonal dysregulation.
- Impact of dietary supplements (calcium, vitamin D) on BMD preservation.
Conclusion
This cohort study provides critical insights into BMD changes in untreated HIV-infected adults in China. The high prevalence of osteopenia, anatomical predilection for the lumbar spine and hip trochanters, and the centrality of low BMI as a risk factor highlight the need for proactive bone health management in this population. Early screening and nutritional interventions may reduce fracture risks and improve long-term quality of life.
doi.org/10.1097/CM9.0000000000001317
Was this helpful?
0 / 0