title: Female gender as a risk factor for transient post-thyroidectomy hypocalcemia.
abstract: OBJECTIVE
  Transient post-thyroidectomy hypocalcemia is a common complication following thyroid surgery. Studies have identified risk factors and possible ways to help predict post-thyroidectomy hypocalcemia with the intent of ultimately limiting its incidence. This study evaluates the role of patient gender as a potential risk factor.
  
  
  METHODS
  A retrospective case series with chart review of 270 consecutive total thyroidectomy patients was conducted.
  
  
  METHODS
  Jewish General Hospital, a McGill University-affiliated hospital in Montreal, Canada.
  
  
  METHODS
  219 women and 51 men were included. Postoperative hypocalcemia was defined as any 1 of the following: total serum calcium 1.90 mmol/L or less, or signs and symptoms of hypocalcemia. The following were evaluated as potential confounding factors in the study: age, menopause, preoperative calcium, parathyroid hormone, magnesium and phosphate levels, presence of carcinoma in the surgical specimen, number of parathyroid glands preserved in situ, thyroid gland volume, and nodule size.
  
  
  RESULTS
  Female patients experienced transient postoperative hypocalcemia in 24.7% (54/219) of cases, which was significantly greater than the 11.8% (6/51) incidence detected in men (P < .05). This represents a female/male relative risk ratio of 2.1 (confidence interval, 1.0-4.6). There was no significant difference in rates of hypocalcemia between premenopausal and postmenopausal women (22.7% vs 26.6%).
  
  
  CONCLUSIONS
  These findings suggest that being female is likely a risk factor for transient post-thyroidectomy hypocalcemia. Although this association is statistically significant, its magnitude and clinical relevance are uncertain and may be trivial. Additional research is needed to ascertain the physiologic mechanisms underlying this gender difference.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Jewish General Hospital, McGill University, Montreal, Canada.
authors.forename: Noah B
authors.initials: NB
authors.lastname: Sands
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Payne
authors.forename: Valerie
authors.initials: V
authors.lastname: Côté
authors.forename: Michael P
authors.initials: MP
authors.lastname: Hier
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Black
authors.forename: Michael
authors.initials: M
authors.lastname: Tamilia
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002118:Calcium / Q000097:blood; D005260:Female; D006111:Graves Disease / Q000453:epidemiology; D050031:Hashimoto Disease / Q000453:epidemiology; D006801:Humans; D006996:Hypocalcemia / Q000453:epidemiology* / Q000517:prevention & control; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood; D011183:Postoperative Complications / Q000453:epidemiology* / Q000517:prevention & control; D012189:Retrospective Studies; D012307:Risk Factors; D012737:Sex Factors; D013965:Thyroidectomy; D013997:Time Factors; D055815:Young Adult
chemical_list: D010281:Parathyroid Hormone; D002118:Calcium