Trabecular Bone Score, Bone Mineral Density and Bone Markers in Patients with Primary Hyperparathyroidism 2 Years After Parathyroidectomy

Abstract

Following a parathyroidectomy there is a bone mineral density (BMD) improvement in patients with primary hyperparathyroidism. However, data of bone microarchitecture are scarce. Trabecular bone score (TBS) estimates bone microarchitecture and could provide valuable information in those patients. The aim of this study is to assess TBS changes 2 years after successful surgery in a group of patients with primary hyperparathyroidism and correlate these results with changes in BMD and bone turnover markers. This is a prospective study including 32 patients. In all participants BMD and TBS were measured, before and 24 months after surgery. Biochemical data: serum calcium, PTH, 25-OH-vitamin D, beta-crosslaps, bone alkaline phosphatase, and osteocalcin. 25 female and 7 male patients, mean age 64.6±12.4 years, were included in the study. At baseline, BMD was low at: lumbar spine (T-score -2.19±1.31), total hip (-1.33±1.12), femoral neck (-1.75±0.84), and distal one-third radius (-2.74±1.68). Baseline TBS showed partially degraded microarchitecture (1.180±0.130). After parathyroidectomy lumbar spine BMD increased significantly (5.3±13.0%, p<0.05), as well as total hip (3.8±8.8%, p<0.05). There was an increase in TBS, but this was not significant. There was a correlation between TBS and BAP at baseline (r_s=0.73; p<0.01) and TBS and BAP 2 years after surgery (r_s=0.57, p<0.05). Although bone density improves 2 years after surgery in patients with primary hyperparathyroidism and there is a restoration of bone turnover markers, TBS is not completely restored. These results remark the necessity of longer periods of study, to confirm if bone microarchitecture could be completely restored after surgery.