title: Determinants of postoperative hypocalcemia in vitamin D-deficient Graves' patients after total thyroidectomy.
abstract: BACKGROUND
  The etiology of postoperative hypocalcemia after total thyroidectomy appears to be multifactorial, that is, postoperative transient hypoparathyroidism, low 25-hydroxy vitamin D (25-OHD) concentrations, aging, and hyperthyroidism with increased bone turnover. Our aim was to evaluate the factors responsible for postoperative hypocalcemia in euthyroid vitamin D-deficient/insufficient Graves patients who underwent total thyroidectomy at our institution.
  
  
  METHODS
  Thirty-five consecutive patients with Graves disease treated by total thyroidectomy were included in the present study. All patients were vitamin D deficient/insufficient (ie, 25-OHD concentrations of <20/<30 ng/mL, respectively). Patients were divided into 2 groups according to postoperative serum albumin corrected calcium concentrations: group 1 (n = 13) patients had postoperative serum calcium concentrations of 8 mg/dL or less; group 2 (n = 22) patients had serum calcium concentrations greater than 8 mg/dL. Bone turnover markers (deoxypiridinoline, bone-specific alkaline phosphatase) and 25-OHD were determined the day before surgery.
  
  
  RESULTS
  In group 1 patients, disease duration was significantly longer, 25-OHD and postoperative parathyroid hormone concentrations were significantly lower, and bone turnover markers were significantly higher. Logistic regression analysis revealed that a postoperative parathyroid hormone concentration less than 10 pg/mL was the most powerful parameter to predict postoperative hypocalcemia (odds ratio, 23; 95% confidence interval, 3.3-156).
  
  
  CONCLUSIONS
  In Graves patients with vitamin D deficiency/insufficiency, postoperative (transient) hypoparathyroidism is the most significant parameter to determine the development of postoperative hypocalcemia.
authors.affiliation: Department of General Surgery, Istanbul University, 34093 Capa, Istanbul, Turkey. yerbil2003@yahoo.com
authors.forename: Yeşim
authors.initials: Y
authors.lastname: Erbil
authors.forename: Nese Colak
authors.initials: NC
authors.lastname: Ozbey
authors.forename: Serkan
authors.initials: S
authors.lastname: Sari
authors.forename: Haluk Recai
authors.initials: HR
authors.lastname: Unalp
authors.forename: Orhan
authors.initials: O
authors.lastname: Agcaoglu
authors.forename: Feyzullah
authors.initials: F
authors.lastname: Ersöz
authors.forename: Halim
authors.initials: H
authors.lastname: Issever
authors.forename: Selçuk
authors.initials: S
authors.lastname: Ozarmagan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D002118:Calcium / Q000097:blood*; D005260:Female; D005500:Follow-Up Studies; D006111:Graves Disease / Q000097:blood / Q000150:complications / Q000601:surgery*; D006801:Humans; D006996:Hypocalcemia / Q000097:blood / Q000175:diagnosis* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood*; D011183:Postoperative Complications; D012189:Retrospective Studies; D013965:Thyroidectomy / Q000009:adverse effects; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood / Q000150:complications / Q000601:surgery*; D055815:Young Adult
chemical_list: D015415:Biomarkers; D010281:Parathyroid Hormone; D014807:Vitamin D; C104450:25-hydroxyvitamin D; D002118:Calcium