Prevention of hypocalcemia and improvement of bone mineral density after parathyroidectomy: a cohort study

BACKGROUND: Primary hyperparathyroidism is associated with a risk of postoperative hypocalcemia and decreased bone mineral density.

AIM: This study aimed to assess the need for prophylactic vitamin D supplementation in patients with primary hyperparathyroidism after parathyroidectomy to reduce the risk of hypocalcemia and increase bone mineral density.

METHODS: An interventional study conducted at the Republican Clinical Hospital for War Veterans of the Chuvash Republic in 2023–2025 included 126 patients with verified primary hyperparathyroidism who underwent parathyroidectomy. The main group (n = 63) consisted of patients who received cholecalciferol at 2800 IU/day in the postoperative period for 6 months. Depending on the clinical and laboratory variant of the disease course, subgroups with hypercalcemic (n = 28) and normocalcemic (n = 35) forms were identified in the main group. The control group (n = 63) consisted of patients who did not receive prophylactic vitamin D. The groups were comparable in terms of sex, age, baseline parathyroid hormone and calcium levels, and X-ray densitometry data of the lumbar spine and femoral neck. The groups were formed using simple randomization. One year after surgery, bone mineral density was assessed using dual-energy X-ray absorptiometry. StatTech 4.4.1 was used for statistical analysis. Quantitative variables are presented as median and interquartile range [Me (Q1; Q3)], and categorical data as absolute values and percentages (n; %). Mann–Whitney U test was used to compare independent groups by quantitative variables, and the Wilcoxon test was used to assess changes in paired observations. Differences were considered significant at p < 0.05.

RESULTS: One year after surgery, patients were invited for an outpatient visit. Patients in the main group demonstrated higher bone mineral density in the lumbar spine (median T score: −1.5 vs −2.1; p = 0.011) and femoral neck (−1.7 vs −2.0; p = 0.031), as well as lower parathyroid hormone levels (3.4 nmol/L vs 5.2 nmol/L; p = 0.001) compared with the control group. Total calcium levels did not differ significantly between the groups. The increase in bone mineral density in the lumbar spine was 4.25% in the main group and 3.41% in the control group (p = 0.011). The increase bone mineral density in the femoral neck area was 5.05% in the main group, which was significantly higher than in the control group (4.06%; p = 0.031).

CONCLUSION: Prophylactic vitamin D supplementation after parathyroidectomy reduces the risk of postoperative hypocalcemia and promotes higher bone mineral density. Patients receiving cholecalciferol demonstrated a greater increase in bone mineral density and lower parathyroid hormone levels.