Endocrine Abstracts

Introduction: Primary hyperparathyroidism (PHPT) is generally associated with increased fracture risk at all skeletal sites although greater bone loss is observed at the cortical than the trabecular bone sites. AsBMD alone does not adequately predict fracture risk, trabecular bone score (TBS) is proposed as a new method supporting risk assessment.

The aim of this study was to investigate correlation between TBS andthe severity of primary hyperparathyroidism.

Methods: The study group consisted of 29 postmenopausal women (age 64.6 ± 8.2 years) with PHPT. Seven patients were diagnosed with kidney stones, two had bone fracturesand 1 had recurrent pancreatitis. In all patients BMD was measured by DXA at the lumbar spine (LS), the femur neck (FN), the distal third of the radius(R1/3) and the distal tenth of the radius (RUD). TBS was measured in LS –BMD. The correlation between TBS, BMD, laboratory results and clinical symptoms of PHPT were evaluated.

Results: BMD mean values (T-score) for LS, FN, R1/3 and RUD were −2.5 ± 1.4, −1,7 ± 0.6, −3.1 ± 1.4, −2.4 ± 1.07, respectively. TBS mean value was 1.1 ± 0.12 (T-score – (–) 3.2 ± 1.4) which means high risk of fractures. Serum parathormone concentration was 206 ± 191 ng/l, serum calcium concentration 11.3 ± 1.2 mg/dl and serum phosphate concentration was 2.5 ± 0.2 mg/dl. There was no correlation between TBS and biochemical parameters such as: PTH, calcium, phosphate and 25-OH-Vitamin D, alkaline phosphatase, serum creatinine concentration andurine calcium excretion. The only correlation found was positive correlation between TBS and BMD at the ultradistal radius region (Spearman’s R = 0.48, P < 0.05). We did not observe any correlation between TBS andtime since menopause or time since diagnosis of hyperparathyroidism. Body weight and BMI exerted a negative effect on TBS (R = −0.54 and R = −0.38 respectively, P <0.05).

Conclusions: Our observations suggest that TBS is not strongly associated withthe severity of PHPT. However, TBS value in patients with PHPT is significantly decreased, hence to determine its role as a predictor of bone fractureit is necessary to conduct long-term studiesin larger groups, especially in patients with fractures.