Predictive value of serum corrected calcium and iPTH levels for hypoparathyroidism after total thyroidectomy / 中华地方病学杂志

ABSTRACT

Objective:To explore the predictive value of serum corrected calcium and intact parathyroid hormone (iPTH) for hypoparathyroidism after total thyroidectomy.Methods:A prospective study was used to select 86 patients with papillary thyroid carcinoma who underwent total thyroidectomy and central lymph node dissection in Chizhou people's Hospital from June 2017 to June 2019 as the observation objects, and the occurrence of postoperative hypoparathyroidism and its risk factors were analyzed. According to the occurrence of postoperative hypoparathyroidism, the patients were divided into hypoparathyroidism group and non-hypoparathyroidism group, the levels of serum corrected calcium and iPTH of patients in two groups were compared before operation, 1, 3 days after operation, and during follow-up (6 months after operation). Receiver operating characteristic (ROC) curve was used to evaluate the predictive value of serum corrected calcium and iPTH levels in patients with hypoparathyroidism after total thyroidectomy on the first day after surgery.Results:Among 86 patients with papillary thyroid carcinoma, 17 were males and 69 were females, aged (46.3±5.6) years old; 42 patients had postoperative hypoparathyroidism (48.84%); among them, 32 cases (37.21%) had hypocalcemia in different degrees, and 2 cases (2.33%) had permanent hypoparathyroidism. Logistic analysis showed that extraglandular invasion [odds ratio ( OR)=19.28, 95% confidence interval ( CI) 2.63-136.81], bilateral central lymph node dissection ( OR=1.84, 96% CI 1.36-9.13) were risk factors for hypoparathyroidism after total thyroidectomy. There were no significant differences in serum corrected calcium and iPTH levels between hypoparathyroidism group and non-hypoparathyroidism group before and 6 months after operation ( P > 0.05); the serum corrected calcium and iPTH levels in the hypoparathyroidism group were significantly lower than those in non-hypoparathyroidism group 1 and 3 days after operation ( P < 0.01). The ROC curve results showed that the area under the curve (AUC) of serum corrected calcium was 0.724, the sensitivity and specificity were 76.68% and 62.14%, respectively; the AUC of iPTH was 0.947, the sensitivity and specificity were 97.68% and 92.14%, respectively. Conclusion:Extraglandular invasion and bilateral central lymph node dissection are risk factors for hypoparathyroidism after total thyroidectomy, and the iPTH level is a more reliable predictor of hypoparathyroidism.