Background Patients infected with the human immunodeficiency virus (HIV) have a high rate of low bone mineral density (BMD) and is thought to be multifactorial. Some instruments have been developed to estimate the risk of osteoporotic fracture in the general population such as the WHO Fracture Risk Assessment Tool (FRAX), which allows calculating the 10-year probability of fractures in men and women from clinical risk factors with or without the measurement of femoral neck BMD. The cut-off values for high risk of hip fracture >3% and for major osteoporotic fracture >20%. Although FRAX has been validated in multiple large cohorts, still there are no clear recommendations of its use in HIV-infected patients older than 50 years.
Objectives To evaluate the utility of FRAX tool in the prediction of risk of vertebral morphometric deformity (MVD) in HIV-infected patients over 50 years old seen in a Spanish tertiary care center.
Methods We performed a cross-sectional study in HIV-infected patients with age 50 years treated in our centre during the period 2014–2016. Demographics and risk factors were collected through a specific survey. FRAX was calculated adding HIV as a cause of secondary osteoporosis in all patients with and without BMD measured by dual-energy X-ray absorptiometry scan (DXA). The MVD were assessed using the Genant's semiquantitative method. The sensitivity and specificity of the test were assessed and correlations made with the presence of MVD.
Results A total of 121 patients were included, 34 women (28%), with a mean age of 54.1 years (range: 50–75). MVD was detected in 25 cases (21%). The patients presented with a mean BMI of 23.7 kg/m2, 33% were smokers, 7% had a consumption of ≥3 doses of alcohol per day, 9% had a family history of hip fracture but no patient presented with previous history of fracture, corticoid treatment or rheumatoid arthritis. The mean FRAX score for major osteoporotic fracture without BMD was of 2.29 (1.1–8.5), there were 2 patients above 7 and any above 10; the mean FRAX score for hip fracture without BMD was of 0.64 (0.1–3.9), 2 patients were above 3. With DXA, osteoporosis in femoral neck was detected in 8% and in the lumbar spine in 30%, while femoral neck osteopenia was detected in 64% and in the lumbar spine in 45%. Including DXA data, the mean FRAX score for major osteoporotic fracture was 2.52 (0.2–8.2), 2 patients were above 7, and for hip fracture the mean FRAX score was 0.67 (0.01–4.4), with 2 patients above 3. The values of FRAX with DXA or without DXA were very similar, with a variation of -0.4 for the mean value of major osteoporotic fracture and +0.03 for the mean value of hip fracture. In ROC curve, a value above 1 in FRAX for hip fracture with DXA, detected 9 MVD of 29 patients (sensitivity 38%, specificity 80%), a value above 2 detected 4 MVD of 10 patients (sensitivity 17%, specificity 93%) and a value of 3 detected 1 MVD of 2 patients (sensitivity 4%, specificity 99%).
Conclusions The FRAX tool does not identify properly the HIV-infected patients older than 50 years with MVD as well as the patients who need DXA. An alternative could be to perform X-rays of thoracic and lumbar spine as a screening method in HIV-infected patients with risk factors.
Disclosure of Interest None declared