A novel index to predict postoperative hypocalcemia in primary hyperparathyroidism

Area of Science:

• Endocrinology
• Surgical Oncology
• Metabolic Bone Disease

Background:

• Vitamin D deficiency is prevalent in hyperparathyroidism patients.
• The role of preoperative Vitamin D replacement is debated.
• High bone turnover may increase postoperative hypocalcemia risk.

Purpose of the Study:

• To investigate the predictive value of the preoperative ALP/Vit D ratio for postoperative hypocalcemia.
• To assess the relationship between bone turnover markers and hypocalcemia risk after surgery.

Main Methods:

• Retrospective analysis of 158 primary hyperparathyroidism patients operated between 2015-2022.
• Evaluation of preoperative laboratory results, including ALP and Vitamin D levels.
• Calculation of the ALP/Vit D ratio to predict postoperative hypocalcemia.

Main Results:

• Univariable analysis identified Vitamin D deficiency/insufficiency, ALP, ALP/Vit D ratio, and T score as significant factors.
• Multivariate analysis confirmed the ALP/Vit D ratio as an independent predictor of hypocalcemia.
• An ALP/Vit D ratio > 6.34 was associated with a 45-fold increased risk of hypocalcemia (p<0.001).
• The ALP/Vit D ratio demonstrated 87.2% sensitivity and 87.1% specificity in predicting hypocalcemia.

Conclusions:

• Vitamin D deficiency alone is insufficient for predicting postoperative hypocalcemia.
• The preoperative ALP/Vit D ratio is the strongest predictor of hypocalcemia risk in these patients.
• This ratio is particularly valuable for identifying patients with high bone turnover who are at increased risk.