title: High postoperative serum cortisol level is associated with increased risk of cognitive dysfunction early after coronary artery bypass graft surgery: a prospective cohort study.
abstract: BACKGROUND
  Stress response induced by surgery is proposed to play an important role in the pathogenesis of postoperative cognitive dysfunction.
  
  
  OBJECTIVE
  To investigate the association between postoperative serum cortisol level and occurrence of cognitive dysfunction early after coronary artery bypass graft surgery.
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  Two teaching hospitals.
  
  
  METHODS
  One hundred and sixth-six adult patients who were referred to elective coronary artery bypass graft surgery from March 2008 to December 2009.
  
  
  METHODS
  None.
  
  
  METHODS
  Neuropsychological tests were completed one day before and seven days after surgery. Cognitive dysfunction was defined using the same definition as used in the ISPOCD1-study. Blood samples were obtained in the first postoperative morning for measurement of serum cortisol concentration. Multivariate Logistic regression analyses were performed to assess the relationship between serum cortisol level and occurrence of postoperative cognitive dysfunction.
  
  
  RESULTS
  Cognitive dysfunction occurred in 39.8% (66 of 166) of patients seven days after surgery. Multivariate Logistic regression analysis showed that high serum cortisol level was significantly associated with the occurrence of postoperative cognitive dysfunction (odds ratio [OR] 2.603, 95% confidence interval [CI] 1.371-4.944, P = 0.003). Other independent predictors of early postoperative cognitive dysfunction included high preoperative New York Heart Association functional class (OR 0.402, 95% CI 0.207-0.782, P = 0.007), poor preoperative Grooved Pegboard test score of nondominant hand (OR 1.022, 95% CI 1.003-1.040, P = 0.020), use of penehyclidine as premedication (OR 2.565, 95% CI 1.109-5.933, P = 0.028), and occurrence of complications within seven days after surgery (OR 2.677, 95% CI 1.201-5.963, P = 0.016).
  
  
  CONCLUSIONS
  High serum cortisol level in the first postoperative morning was associated with increased risk of cognitive dysfunction seven days after coronary artery bypass graft surgery.
authors.affiliation: Department of Anesthesiology and Surgical Intensive Care Peking University First Hospital, Beijing, China.
authors.forename: Dong-Liang
authors.initials: DL
authors.lastname: Mu
authors.forename: Li-Huan
authors.initials: LH
authors.lastname: Li
authors.forename: Dong-Xin
authors.initials: DX
authors.lastname: Wang
authors.forename: Nan
authors.initials: N
authors.lastname: Li
authors.forename: Guo-Jin
authors.initials: GJ
authors.lastname: Shan
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.forename: Qin-Jun
authors.initials: QJ
authors.lastname: Yu
authors.forename: Chun-Xia
authors.initials: CX
authors.lastname: Shi
mesh_terms: D000328:Adult; D003072:Cognition Disorders / Q000097:blood* / Q000209:etiology / Q000503:physiopathology*; D015331:Cohort Studies; D001026:Coronary Artery Bypass / Q000009:adverse effects*; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000097:blood* / Q000209:etiology / Q000503:physiopathology*; D011184:Postoperative Period; D011446:Prospective Studies; D012306:Risk
chemical_list: D006854:Hydrocortisone