Endocrine Abstracts

Background/aim: Primary hyperparathyroidism (pHPT) is a relatively common endocrine disorder, which is associated with severe disruption of calcium metabolism and deterioration of bone density and quality. Our study aimed at examining the effect of parathyroidectomy on bone mineral density (BMD), T-Score in both the femoral neck (FN) and the lumbar spine (LS) and on trabecular bone score (TBS).

Materials and methods: A cohort of 280 adult patients (195 males and 85 females), diagnosed with non-syndromic pHPT (from 1998 to 2023), who underwent parathyroidectomy and were followed-up post-surgically in our endocrine center, was retrospectively evaluated. Demographic, clinical and laboratory data of these patients at the time of diagnosis of pHPT and 1 year after parathyroidectomy were evaluated.

Results: Mean age and body mass index of the patients at diagnosis were 54.1 years and 28.6 kg/m² respectively. Mean PTH and corrected serum calcium values decreased significantly 1 year after parathyroidectomy (PTH: 65.3±44.3 vs 307.5±284.9 ng/l, P<0.01; corr Ca: 9.2±0.6 vs 11.9±1.8 mg/dl, P=0.014, respectively). BMD values were dramatically increased 12 months after parathyroidectomy in both the FN and the LS (LS BMD: 0.792±0.133 vs 0.731±0.105, P < 0.01, FN BMD: 0.611±0.123 vs 0.544±0.110, P=0.022 respectively). The same positive observation applied in case of T-Score values in both sites post-parathyroidectomy (LS T-score: −1.3±0.9 vs −2.2±1.3, P<0.01; FN T score: −1.5±0.6 vs −2.3±0.9, P=0.016). Interestingly, pre-operative PTH values were found to be moderately and inversely associated with the post-operative BMD and T-Score values in both the LS (r=−0.44, P=0.013; and r=−0.56, P=0.022 respectively) and the FN (r=−0.52, P=0.018; and r=−0.58, P=0.015 respectively). Finally, the evaluation with TBS pre- and post-operatively identified no significant alterations (TBS pre- and post-operatively: 1.23±0.12 vs 1.25±0.15, P=0.37).

Conclusions: The results of our study indicate that the surgical treatment of pHPT can potentially lead to significant improvement of BMD and T-Score values already after 1-year time. Nonetheless, higher biochemical severity of pHPT could be associated to limited recovery of bone metabolism post-surgically. Unfortunately, bone microarchitecture seems to remain relatively unaffected from the parathyroidectomy, thus possibly indicating irreversible effects of pHPT on bone structural integrity. Further long-term study and evaluation of the impact of parathyroidectomy on bone metabolism and quality of patients with pHPT is needed.