Predictors of Poor Bone Microarchitecture Assessed by Trabecular Bone Score in Postsurgical Hypoparathyroidism

The effects of PTH deprivation on bone are still unclear. Our objective was to report the characteristics of patients with postsurgical hypoparathyroidism (PsH) at a specialized outpatient service and correlate their trabecular bone score (TBS) values to clinical, densitometric, and laboratory findings. A secondary objective was to evaluate the fracture rates and look for associations between these events and the collected data.

Eighty-two patients were enrolled, of whom 70 (85.4%) were female and 17 (20.7%) had type 2 diabetes mellitus (T2DM). The median body mass index (BMI) was 27.7 kg/m2 and the median age was 59 years. Of 68 dual-energy x-ray absorptiometry (DXA) scans obtained, osteopenia and osteoporosis were present in 32.4% and 2.9%, respectively. In all, 62 lumbar scans were analyzed by using TBS. The mean TBS value (±SD) was 1.386 ± 0.140, and 32.2% of the results were <1.310. TBS values correlated negatively with BMI (mainly > 30 kg/m2), age (mainly > 60 years), and glycemia, whereas abnormal TBS correlated with osteopenia, T2DM, low-impact fracture, and menopause. Six female patients had low-impact fractures, which were associated with a lower TBS (1.178 ± 0.065 vs. 1.404 ± 0.130 in the group without fractures; P < 0.001), older age, higher BMI, impaired renal function, abnormal glycemia, and osteopenia.

The findings suggests that known risk factors for bone loss compromise the bone microarchitecture of individuals with PsH, regardless of DXA results. Menopausal women with PsH and older patients with PsH who have osteopenia, a higher BMI, or T2DM may be candidates for a more detailed assessment by using, for example, TBS.