Heel quantitative ultrasound in HIV-infected patients: a cross-sectional study.

PURPOSE: HIV infection has been associated with increased risk of osteoporosis and fragility fractures. Dual-energy X-ray absorptiometry (DXA) is the reference standard to assess bone mineral density (BMD); however, it is not easily accessible in several settings. Heel Quantitative ultrasound (QUS) is a radiation-free, easy-to-perform technique, which may help reducing the need for DXA. METHODS: In this cross-sectional study, we used heel QUS (Hologic Sahara®) to assess bone status in a cohort of HIV-infected patients. A QUS stiffness index (QUI) threshold >83 was used to identify patients with a low likelihood of osteoporosis. Moreover, we compared QUS results with those of 36 sex- and age-matched HIV-negative controls. RESULTS: 244 HIV-positive patients were enrolled. Median heel QUI value was 83 (73-96) vs. 93 (IQR 84-104) in the control group (p = 0.04). 110 patients (45 %) had a QUI value ≤83. Risk factors for low QUI values were age (OR 1.04 per year, 95 % CI 1.01-1.07, p = 0.004), current use of protease inhibitors (OR 1.85, CI 1.03-3.35, p = 0.039), current use of tenofovir (OR 2.28, CI 1.22-4.27, p = 0.009) and the number of risk factors for secondary osteoporosis (OR 1.46, CI 1.09-1.95, p = 0.01). Of note, QUI values were significantly correlated with FRAX score (r = -0.22, p = 0.004). According to EACS guidelines, 45 % of patients had risk factors for osteoporosis which make them eligible for DXA. By using QUS, we may avoid DXA in around half of them. CONCLUSIONS: As HIV-positive patients are living longer, the prevalence of osteoporosis is expected to increase over time. Appropriate screening, prevention and treatment are crucial to preserve bone health in this population. The use of screening techniques, such as heel QUS, may help reducing the need for DXA. Further studies are needed to define the diagnostic accuracy of this promising technique in the setting of HIV.