Primary hyperparathyroidism (PHPT) exhibits three biochemical phenotypes: classic hypercalcemic, normocalcemic, and normohormonal. Elevated parathyroid hormone causes high bone turnover, decreasing bone mineral density (BMD), particularly in cortical sites, resulting in osteopenia or osteoporosis with a greater fracture risk. This prospective study aims to identify factors influencing BMD changes and determine optimal surgical candidates among these clinical presentations.

The study included 109 patients diagnosed with PHPT who underwent parathyroidectomy (PTX) between 2017 and 2020. Sociodemographic profiles, biochemistry results and both pre-operative and one-year postoperative dual energy X-ray absorptiometry (DXA) scans conducted in the same facility were used to compare BMD gain. We also divided patients into three subgroups (hypercalcemic, normocalcemic and normohormonal) to examine the difference between BMD gains.

One year post-parathyroidectomy, bone mineral density significantly increased at lumbar spine (LS), total hip (TH), and femoral neck (FN). No change occurred in 1/3 of the radius for both BMD and t-score gain. Gender and age lacked correlation with BMD gain. Post-operative low phosphorous levels correlated with higher BMD gain. The greatest decrease in parathormone (PTH) post-operatively correlated with increased BMD and t-score in LS and FN. Higher preoperative urinary calcium associated with greater BMD and t-score gain in TH. Three primary hyperparathyroidism (PHPT) subgroups exhibited similar postoperative BMD gain.

Parathyroidectomy significantly improves bone mineral density (BMD) in primary hyperparathyroidism patients. Severe biochemical profiles exhibit a greater increase in BMD and t-score, while even asymptomatic patients show significant BMD gain. Patients with PHPT, irrespective of age and sex, benefit from parathyroidectomy.