Radiofrequency echographic multi spectrometry for the prediction of incident fragility fractures: A 5-year follow-up study

Purpose: To investigate the effectiveness of the T-score values provided by Radiofrequency Echographic Multi Spectrometry (REMS) in the identification of patients at risk for incident osteoporotic fractures. Methods: A population of Caucasian women (30-90 years), enrolled from 2013 to 2016, underwent dual X-ray absorptiometry (DXA) and REMS scans at axial sites. The incidence of fragility fractures was assessed during a follow-up period up to 5 years. Afterwards, patients with and without incident fractures were stratified in two age-matched groups with a 1: 2 proportion (Group F' and Group NF', respectively). The performance of REMS T-score in discriminating between the two groups was quantitatively assessed and compared with DXA. Results: 1516 patients were enrolled and 1370 completed the follow-up (mean +/- SD: 3.7 +/- 0.8 years; range: 1.9-5.0 years). Fracture incidence was 14.0%. Age-matched groups included 175 fractured patients and 350 non-fractured ones, respectively (median age 70.2 [interquartile range: 61.0-73.3] and 67.3 [65.4-69.8] years, p-value ns). The groups resulted also balanced for height, weight and BMI (p-values ns). As expected, the differences in REMS T-score (for vertebral site, - 2.9 [ - 3.6 to -1.9] in Group F', - 2.2 [ - 2.9 to -1.2] in Group NF') and DXA T-score ( - 2.8 [ - 3.3 to -1.9] in Group F', - 2.2 [ - 2.9 to -1.4] in Group NF') were statistically significant (p-value < 0.001). Analogous results were obtained for femoral neck. Considering the T-score cut-off of - 2.5, REMS identified Group F' patients with a sensitivity of 65.1% and specificity of 57.7% of (OR = 2.6, 95%CI: 1.77-3.76, p < 0.001), whereas DXA showed a sensitivity of 57.1% and a specificity of 56.3% (OR = 1.7, 95%CI: 1.20-2.51, p-value = 0.0032). For femoral neck, REMS sensitivity and specificity were 40.2% and 79.9%, respectively, with an OR of 2.81 (95%CI: 1.80-4.39, p < 0.001). DXA, instead, showed a sensitivity and specificity of 42.3% and 79.3%, respectively, with an OR of 2.68 (95%CI: 1.71-4.21, p < 0.001). Conclusions: REMS T-score resulted an effective predictor for the risk of incident fragility fractures in a population-based sample of female subjects, representing a promising parameter to enhance osteoporosis diagnosis in the clinical routine.