Incidence of Post-Thyroidectomy Hypoparathyroidism and Associated Preoperative and Intraoperative Risk Factors

Introduction: Thyroidectomy technique and extent are related to parathyroid injury and hypoparathyroidism. Total thyroidectomy is one of the most commonly performed endocrine surgeries, and the majority of patients recover completely without any complications. However, persistent hypoparathyroidism is the most prevalent long-term consequence following total thyroidectomy. While it is seldom deadly, it can cause severe morbidity for the patient and raise healthcare expenses. Methods: This retrospective cohort study was conducted at King Abdulaziz Medical City, Jeddah, Saudi Arabia. We included all confirmed thyroid cancer cases that underwent thyroidectomy with or without neck dissection between July 2016 and August 2022. The data was collected from a chart review of the electronic medical record system (BEST-care), and a data collection sheet was utilized. SPSS version 26 was used to analyze the data. Results: A total of 192 patients undergoing thyroid surgery were enrolled. One hundred forty-three (74.5%) were females and the mean age of participants was 45.29 ± 16.88 years. Most patients, 170 (88.5%), had a papillary histological type, and total thyroidectomy was performed in 150 (78.1%). A significant association was found between the type of surgery and postoperative hypoparathyroidism (p=<0.05*). In addition, hypocalcemia was seen in 147 (76.6%) of the patients. Postoperative hypoparathyroidism was significantly higher among patients who had asymptomatic postoperative hypocalcemia and those who received IV calcium gluconate (p=<0.05*). Moreover, postoperative hypocalcemia, hypomagnesemia, and hyperphosphatemia were significantly associated with postoperative hypoparathyroidism (p=<0.05*). Conclusion: The incidence of postoperative hypoparathyroidism is significantly higher among patients who underwent total thyroidectomy and had a normal level of preoperative parathyroid hormone (PTH) and magnesium (Mg) levels. Identifying these factors is a crucial step to minimize the occurrence of such complications.