title: Postoperative hypomagnesaemia is not associated with hypocalcemia in thyroid cancer patients undergoing total thyroidectomy plus central compartment neck dissection.
abstract: BACKGROUND
  The literature remains scarce and controversial regarding the association of hypomagnesaemia and hypocalcemia after total thyroidectomy. This study aims to assess this association in thyroid cancer patients underwent total thyroidectomy (TT) plus central compartment neck dissection (CCND).
  
  
  METHODS
  All consecutive thyroid cancer patients who underwent TT plus CCND were retrospectively reviewed through a prospectively collected database between October 2015 and June 2016 in a tertiary referral hospital. The univariate and multivariate analysis were performed to identify the significant predictors for hypocalcemia.
  
  
  RESULTS
  A total of 237 patients were included. The incidence of postoperative biochemical and symptomatic hypocalcemia was 52.3% (124 patients) and 33.8% (80 patients), respectively. Multivariate analysis showed that only postoperative hypoparathyroidism was an independent predictor for biochemical hypocalcemia (HR = 14.37, 95%CI = 6.07-34.0; P < 0.000), while parathyroid gland autotansplantation (HR = 2.02, 95%CI = 1.04-3.91; P = 0.038) and hypoparathyroidism (HR = 7.47, 95%CI = 3.84-14.5; P < 0.000) were independent risk factor for symptomatic hypocalcemia. Postoperative hypomagnesaemia was not significantly associated with the development of hypocalcemia (P > 0.05).
  
  
  CONCLUSIONS
  Postoperative hypomagnesaemia was not an independent predictor of hypocalcemia after total thyroidectomy. It seems to be unnecessary to routinely monitor the magnesium levels before and after thyroid surgery.
authors.affiliation: Department of Thyroid and Breast Surgery, West China Hospital, Sichuan University, Chengdu, China; Department of General Surgery, Affiliated Hospital of North Sichuan Medical College, Nanchong, China.
authors.forename: Xiaofei
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Thyroid and Breast Surgery, West China Hospital, Sichuan University, Chengdu, China.
authors.forename: Jingqiang
authors.initials: J
authors.lastname: Zhu
authors.affiliation: Department of Thyroid and Breast Surgery, West China Hospital, Sichuan University, Chengdu, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Liu
authors.affiliation: Department of Thyroid and Breast Surgery, West China Hospital, Sichuan University, Chengdu, China.
authors.forename: Yanping
authors.initials: Y
authors.lastname: Gong
authors.affiliation: Department of Thyroid and Breast Surgery, West China Hospital, Sichuan University, Chengdu, China. Electronic address: westchinalzh@163.com.
authors.forename: Zhihui
authors.initials: Z
authors.lastname: Li
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D006996:Hypocalcemia / Q000209:etiology*; D007011:Hypoparathyroidism / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D037981:Neck Dissection / Q000009:adverse effects; D010280:Parathyroid Glands / Q000637:transplantation; D011182:Postoperative Care / Q000379:methods; D012189:Retrospective Studies; D012307:Risk Factors; D013964:Thyroid Neoplasms / Q000601:surgery*; D013965:Thyroidectomy / Q000009:adverse effects*; D019564:Unnecessary Procedures; D055815:Young Adult
keywords: Hypocalcemia; Hypomagnesaemia; Thyroid cancer; Total thyroidectomy