TRABECULAR BONE SCORE (TBS) HAS A POOR DISCRIMINATIVE POWER FOR VERTEBRAL FRACTURES IN 153 ROMANIAN PATIENTS WITH PRIMARY HYPERPARATHYROIDISM

Context. Trabecular Bone Score (TBS) has been recently proposed as a good tool to investigate secondary osteoporosis. Objective. The aim of this study was to assess TBS from spine DXA images in patients with primary hyperparathyroidism (PHPT) and look at its correlates. Subjects and Methods. 153 patients, mean age 59.1 +/- 12.1 yrs, females and males (10%), mean BMI 26.2 +/- 4.8 kg/m(2), mean serum calcium and PTH of 11.3 +/- 1.2 mg/dL and 232 +/- 329 pg/mL, respectively; 89% had osteoporosis/ osteopenia by LS DXA and 46% had renal involvement. There were 7.6% patients with vertebral fractures, 13.2% patients with nonvertebral fractures. TBS indices were derived from LS-DXA images and cutoff points used were those previously reported. Results. Mean TBS was in the partially degraded range (1.258 +/- 0.115); 32% of patients had degraded microarchitecture (TBS <= 1.20), 51% had partially degraded microarchitecture (TBS > 1.20 and < 1.35) and 17% had normal TBS. TBS was significantly correlated with areal BMD both at the LS (r=0.544; p < 0.001) and FN (r = 0.315; p < 0.001), and negatively with age (r= - 0.354; p < 0.001) and years since menopause - YSM (r = - 0.257, p = 0.005). Patients with vertebral fractures had mean values of TBS in the degraded range, significantly lower than those without vertebral fractures (1.173 +/- 0.076 vs. 1.263 +/- 0.115; p = 0.006). The presence of vertebral fracture was independently associated only with YSM (OR =1.131, 95% CI = 0.032 - 0.214, p = 0.008) but not with TBS. Conclusions. In a cohort of symptomatic PHPT patients, including postmenopausal, premenopausal and male patients, we have shown that TBS was in the partially degraded range, but it was not independently associated with fractures.