Endocrine Abstracts

Background: Radiofrequency Echographic Multi Spectrometry (REMS) is a new ultrasound-based tool for bone mineral density (BMD) measurement, recently approved by FDA for the use in clinical routine to diagnose osteoporosis (OP) and to monitor bone changes. However, data on patients with secondary OP are not available. The aim of our study was to compare REMS and DXA ability in identifying clinical (cFX) and morphometric vertebral fractures (VFx) in patients with primary OP (pOP) and with primary hyperparathyroidism (PHPT).

Methods: We enrolled 99 consecutive postmenopausal women referred to our Unit for pOP (n = 52) or PHPT (n = 47), who underwent REMS, DXA and spine X-ray to detect possible VFx. We excluded subjects with history ofbone-active therapy. The same operator executed REMS lumbar spine (LS) and total femural (TF) scan in all patients.

Results: Age, body mass index and BMD at any site, prevalent cFX (18.6% and 20.8%, respectively, P = 0.793) and VFx (21.4% and 22.4%, respectively, P = 0.907) were comparable between pOP and PHPT. The concordance between DXA and REMS in diagnosing osteopenia or OP was below 70% and comparable in pOP and PHPT patients (LS 64% and 58%; TF 66% and 51%, P = ns for all comparisons). The prevalence of OP according to REMS (REMS-OP) was lower than according to DXA (DXA-OP), although not significantly, in both pOP and PHPT groups (26.9% and 65.4%, P = 0.06; 28.6% and 64.3%, P = 0.103 respectively). Altogether, patients with DXA-OP had a higher prevalence of all (cFX+VFx) fractures (42.4% and 21.4%, P = 0.05) and a trend for a higher prevalence of VFx (28.8% and 10.7%, P = 0.06, respectively) as compared with patients without DXA-OP. Conversely, patients with and without REMS-OP had a similar prevalence of all fractures (32.0% and 39.1%, P = ns) and VFx (20.0% and 23.4%, P = ns). Similar results were obtained in both groups. Considering both the whole sample and the pOP and PHPT patients separately, REMS and DXA values were significantly associated, however the strength of correlation was low (LS all r = 0.373, P = 0.001; LS pOP r = 0.371, P = 0.008; LS PHPT r = 0.389, P = 0.14; TF all r = 0.48, P = 0.001; TF pOP r = 0.435, P = 0.02; TF PHPT r = 0.544, P = 0.001; respectively).

Conclusions: In our real life study, REMS seems to overestimate BMD values compared to DXA in both pOP and PHPT patients. REMS reliability in identifying patients with both cFx and VFx, seems to be lower than DEXA, in both pOP and PHPT patients. Future studies are needed to understand how to optimize this however promising technique.