New Fracture Risk And Frax 10-Year Probability Of Fracture In Hiv-Infected Adults


      FRAX reliably predicts 10-year fracture risk for adults in the general population. However, its utility for HIV-infected adults has not been assessed.


      Using dual energy X-ray absorptiometry (DEXA) BMD values of the left femoral neck and clinical data collected prospectively during 2004-2012 from two CDC-sponsored HIV cohorts, we calculated the initial FRAX 10-year risk of a major osteoporotic fracture (MOF) (i.e., of the hip, spine, forearm, or shoulder), assessed rates of any new bone fracture and MOF per 100 person-years (100py) of follow-up stratified by initial FRAX-score intervals, and used Cox proportional hazards models to identify risk factors for new fractures.


      Among 1006 participants, 83% were male, 67% were non-Hispanic white, median age was 42 years, median CD4+ cell count was 408 cells/mm3, median BMD was 0.90 g/cm2, and median FRAX score was 1.9; FRAX scores were higher for those with subsequent fracture vs. those without (p<0.01). During observation after initial DEXA, 95 participants (9.4%) had a new fracture: 7.1% occurred among persons with FRAX score <3% (1.39/100py); 15.3% among persons with FRAX score ≥3% (3.27/100py). MOF occurred among 1.5% of persons with FRAX score <3% (0.30/100py) and 4.9% of persons with FRAX score ≥3% (1.04/100py). In multivariate analyses, having prior fracture (adjusted hazard ratio [aHR] 2.02, 95% confidence interval [CI]: 1.09-3.71), older age (aHR 1.30 per 10 years, CI: 1.04-1.62), and lower BMD (aHR 0.14 per g/cm2, CI: 0.03-0.59) were associated with risk of any new fracture. In a separate model, having FRAX score ≥ 3% vs. FRAX of < 3.0% was associated with any new fracture (HR 2.31, CI: 1.54-3.46).


      In a large convenience sample of relatively young HIV-infected U.S. adults, a FRAX score ≥3%, low baseline BMD, history of prior fracture, and increased age were significantly associated with elevated risk of new fracture.