title: Influence of thyroidectomy on postoperative serum calcium level regarding serum vitamin D status. A prospective study.
abstract: BACKGROUND
  Hypocalcemia is a well-recognized complication after total thyroidectomy. Hypovitaminosis D may have additional effect in the development of hypocalcemia. This study aimed to determine the effect of total thyroidectomy on postoperative serum calcium in patients with and without hypovitaminosis D.
  
  
  METHODS
  This prospective study was performed on patients who underwent total thyroidectomy from 2011 to 2014 in Imam Khomeini General Hospital of Mazandaran University of Medical Sciences. Serum calcium and vitamin D values were recorded before and after surgery. The patients were classified according to serum vitamin D concentrations as less 10 ng/ml (vitamin D deficiency) or higher (control group). The mean values of postoperative calcium level for each class of serum vitamin D were determined and compared. Hypocalcemia was defined as a postoperative calcium level <8 mg/dl.
  
  
  RESULTS
  125 patients due to thyroid disease underwent total thyroidectomy. The incidence of symptomatic and asymptomatic hypocalcemia after surgery was 12% (n=15) and 3.2% (n=4) respectively. 82 (65.6%) patients had vitamin D deficiency and 43 (34.4%) patients had sufficient vitamin D level. There was not any significant difference in calcium level (8.67±0.58 mg/dl vs. 8.70±0.59 mg/dl) between two vitamin D studied groups after thyroid surgery (p>0.05).
  
  
  CONCLUSIONS
  The findings of this study indicated that vitamin D deficiency had no significant effect on post-thyroidectomy serum calcium level.
authors.affiliation: Department of Thoracic Surgery, Imam Khomeini Hospital, Mazandaran University of Medical Sciences, Sari, Iran.
authors.forename: Gholamali
authors.initials: G
authors.lastname: Godazandeh
authors.affiliation: Diabetes Research Center, Mazandaran University of Medical Sciences, Sari, Iran.
authors.forename: Zahra
authors.initials: Z
authors.lastname: Kashi
authors.affiliation: Department of Radiology, Imam Khomeini Hospital , Mazandaran University of Medical Sciences, Sari, Iran.
authors.forename: Farnaz
authors.initials: F
authors.lastname: Godazandeh
authors.affiliation: Department of Thoracic Surgery, Imam Khomeini Hospital, Mazandaran University of Medical Sciences, Sari, Iran.
authors.forename: Pouya
authors.initials: P
authors.lastname: Tayebi
authors.affiliation: Social Determinant of Health Research Center, Babol University of Medical Sciences, Babol, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Bijani
keywords: Hypocalcemia; Hypoparathyroidism; Thyroidectomy; Transient hypocalcemia; Vitamin D deficiency