Hungry bone syndrome is characterized by prolonged and severe hypocalcemia following parathyroidectomy. Previously, we reported that preoperative alkaline phosphatase is a major factor predicting prolonged hospital stay. Nonetheless, some patients with low alkaline phosphatase levels presented with hungry bone syndrome, suggesting that additional factors may play a role.
From September 2010 to December 2017, consecutive dialysis patients who underwent parathyroidectomy for secondary hyperparathyroidism were analyzed. Length of hospital stay was used as a surrogate marker for postoperative bone hunger.
A total of 260 patients were included in the study. The median postoperative hospital stay was 3 days, and 69 (27%) patients had a stay longer than 3 days. Multivariate logistic regression analysis revealed that alkaline phosphatase (odds ratio [OR] = 1.005), osteocalcin (OR = 1.001), and subtotal parathyroidectomy (OR = 0.061) were associated with prolonged hospital stay. Multivariate linear regression analysis indicated that age (β = − 0.170), alkaline phosphatase (β = 0.430), and osteocalcin (β = 0.166) were correlated with the length of stay. After surgery, the median osteocalcin level increased from 264 to 478 ng/mL (P < 0.001).
Alkaline phosphatase is the main predictor of hungry bone syndrome after parathyroidectomy, and preoperative osteocalcin is an additional independent predictor. Patients with a high osteocalcin level may prone to have a higher demand for calcium supplementation.