Abstract
Background. Hypocalcemia is a common complication of total thyroidectomy. It has many consequences for the health of patients and negatively affects the patient’s quality of life. The purpose of this study was to investigate the predictive role of vitamin D serum levels before total thyroidectomy in the occurrence of hypocalcemia.
Methods. This cross-sectional study was conducted on 82 patients who were candidates for total thyroidectomy surgery and referred to 5 Azar Hospital in Gorgan in 2022. Demographic information, laboratory variables, and clinical symptoms of hypocalcemia before surgery, and 24 hours and two weeks after surgery were collected using a checklist. Data were analyzed with SPSS18 software, independent t-tests, U-Man-Whitney, Wilcoxon, paired t-tests, and a Chi-square test at a significance level of 0.05.
Results. The mean serum calcium level was significantly reduced 24 hours and two weeks after surgery. The average serum level of phosphorus also decreased significantly 24 hours after surgery. About 32.9% showed symptoms of hypocalcemia 24 hours after surgery. Hypocalcemia was not related to the serum vitamin D level. The mean serum calcium level was significantly lower in patients with hypocalcemic symptoms. The average parathyroid hormone one day after surgery was significantly higher in patients with normal calcium levels.
Conclusion. Vitamin D serum level before total thyroidectomy is not related to hypocalcemia after total thyroidectomy. Serum levels of parathyroid hormone and phosphorus are related to serum calcium changes after surgery.
Practical Implications. Serum vitamin D levels before thyroidectomy cannot predict hypocalcemia after total thyroidectomy. Serum levels of parathyroid hormone and phosphorus are related to serum calcium changes after surgery. Therefore, long-term follow-up of calcium, vitamin D, parathyroid hormone, and phosphorus levels is recommended for these patients.