Stratifying the risk factors for hypoparathyroidism after total thyroidectomy. A single Center study

Post-operative hypoparathyroidism is a complication in patients who undergo thyroid surgery. Our study aimed to evaluate the incidence and causes of post-operative transient and permanent hypoparathyroidism in patients undergoing thyroid surgery.

The data of 933 consecutive patients who underwent total thyroidectomy in a single center were retrospectively evaluated. The rate of post-operative hypoparathyroidism, clinicopathological features, and laboratory parameters during the post-operative first day, first month, and first year of patients with and without hypoparathyroidism were analyzed. Patients with hypoparathyroidism were classified as transient or permanent cases.

The incidence of post-operative hypoparathyroidism was 22.7%, including transient (20.6%) and permanent (2.1%). In multivariable analysis, independent predictors of permanent hypoparathyroidism were as follows: surgery due to malignant thyroid disease, tumor multifocality, and pre-operative vitamin-D deficiency (VDD) (p<0.001, 0.047, and 0.002, respectively). During the post-operative first month, the mean serum PTH levels were found to be 7.58 pg/mL, and they remained low on the post-operative first year in patients with permanent hypoparathyroidism.

Surgery due to thyroid malignancy and VDD should be considered risk factors for permanent hypoparathyroidism in patients who undergo thyroid surgery. The post-operative first month is important in the prediction of permanent hypoparathyroidism.

Hypoparathyroidism, Permanent, Transient.