321. Low Volumetric Bone Density at Proximal Femur in HIV-Infected Men and Its Risk Factors: Comparison with Community-Dwelling Non-Infected Men

BACKGROUND: Individuals with HIV infection is at increased risk of low area bone mineral density (BMD) and fracture. However, data regarding volumetric BMD (vBMD) of central bone determined by quantitative computed tomography (QCT) which can distinguish the cortical and trabecular bone component are limited. METHODS: From November 2017 to October 2018, we measured spine and hip vBMD in HIV-infected men aged 30 years or older at the tertiary center. QCT data were compared with 1:2 matched control by age- and body mass index (BMI) sampled from a community-based healthy individual cohort. HIV-specific risk factors for low total hip vBMD as a primary outcome were identified using multivariate linear regression models. RESULTS: A total of 83 HIV-infected men and 166 control were analyzed (mean age 47.4 vs. 47.0 year; BMI 23.3 vs. 23.7 kg/m(2); P > 0.05). In HIV-infected men, vBMD of trochanter, intertrochanter and total hip was significantly lower than that of non-infected men. (198 ± 31 vs. 213 ± 32; 339 ± 50 vs. 356 ± 47; 280 ± 41 vs. 296 ± 41 mg/cc; all P < 0.05) Association between HIV infection and lower total hip vBMD remained robust (Adjusted β -14.4; P = 0.013) after adjustment for age, diabetes, smoking, and vitamin D status. In HIV cohort, low CD4 T-cell count at initial diagnosis (< 200 vs. ≥200 cells/μL; Adjusted β = −6.7, P = 0.015) and use of protease inhibitor (vs. integrase inhibitor; Adjusted β = −29.9, P = 0.029) were negatively associated with total hip vBMD, after adjustment for age, BMI, and duration of HIV infection, whereas tenofovir disoproxil fumarate use was not. (Adjusted β −12.1, P = 0.280) In HIV-infected men with low tertile total hip vBMD, the levels of β-crosslaps (0.42 ± 0.23 vs. 0.30 ± 0.16 ng/mL; P = 0.012) and osteocalcin (22.10 ± 8.65 vs. 16.57 ± 6.04 ng/mL; P = 0.001) were higher than those with middle-upper tertile total hip vBMD. CONCLUSION: HIV-infected men had lower hip vBMD compared with age- and BMI-matched non-infected men. Low baseline CD4 T-cell count and protease inhibitor use were independent risk factors for lower total hip vBMD. High born turnover was attributable to the negative effect on born health of HIV-infected men. DISCLOSURES: All authors: No reported disclosures.