Vitamin D Status and the Relationship with Bone Fragility Fractures in HIV-Infected Patients: A Case Control Study.

HIV-infected patients show high risk of fracture. The aims of our study were to determine the prevalence of vertebral fractures (VFs) and their associations with vitamin D in HIV patients. 100 patients with HIV infection and 100 healthy age- and sex-matched controls were studied. Bone mineral density was measured by quantitative ultrasound at the non-dominant heel. Serum osteocalcin and C-terminal telopeptide of collagen type 1 served as bone turnover markers. Bone ultrasound measurements were significantly lower in patients compared with controls (Stiffness Index (SI): 80.58 +/- 19.95% vs. 93.80 +/- 7.10%, respectively, p < 0.001). VFs were found in 16 patients and in 2 controls. HIV patients with vertebral fractures showed lower stiffness index (SI) (70.75 +/- 10.63 vs. 83.36 +/- 16.19, respectively, p = 0.045) and lower vitamin D levels (16.20 +/- 5.62 vs. 28.14 +/- 11.94, respectively, p < 0.02). The majority of VFs (87.5%) were observed in HIV-infected patients with vitamin D insufficiency, and regression analysis showed that vitamin D insufficiency was significantly associated with vertebral fractures (OR 9.15; 95% CI 0.18-0.52, p < 0.04). VFs and are a frequent occurrence in HIV-infected patients and may be associated with vitamin D insufficiency.