title: Raised IL-2 and TNF-α concentrations are associated with postoperative delirium in patients undergoing coronary-artery bypass graft surgery.
abstract: BACKGROUND
  The knowledge base regarding the pathogenesis of postoperative delirium is limited. The primary aim of this study is to investigate whether increased levels of IL-2 and TNF-α are associated with delirium in patients who underwent coronary-artery bypass graft (CABG) surgery with cardiopulmonary bypass (CPB). The secondary aim is to establish whether any association between raised cytokine levels and delirium is related to surgical and anesthetic procedures or mediated by pre-existing conditions associated with raised cytokine levels, such as major depressive disorder (MDD), cognitive impairment, or aging.
  
  
  METHODS
  Patients were examined and screened for MDD and cognitive impairment one day preoperatively, using the Mini International Neuropsychiatric Interview and The Montreal Cognitive Assessment and Trail Making Test Part B. Blood samples were collected postoperatively for cytokine levels.
  
  
  RESULTS
  Postoperative delirium screening was found positive in 36% (41 of 113) of patients. A multivariate logistic regression revealed that an increased concentration of pro-inflammatory cytokines is associated with delirium, and related to advancing age, preoperative cognitive decline of participants, and duration of CPB. According to receiver operating characteristic analysis, the most optimal cut-off for IL-2 and TNF-α concentrations in predicting the development of delirium were 907.5 U/ml and 10.95 pg/ml, respectively.
  
  
  CONCLUSIONS
  The present study suggests that raised postoperative cytokine concentrations are associated with delirium after CABG surgery. Postoperative monitoring of pro-inflammatory markers combined with regular surveillance may be helpful in the early detection of postoperative delirium in this patient group.
authors.affiliation: Department of Old Age Psychiatry and Psychotic Disorders, Medical University of Lodz, Lodz, Poland.
authors.forename: Jakub
authors.initials: J
authors.lastname: Kazmierski
authors.affiliation: Department of Anaesthesiology and Intensive Cardiologic Care, 1st Chair of Cardiology and Cardiac Surgery, Medical University of Lodz, Lodz, Poland.
authors.forename: Andrzej
authors.initials: A
authors.lastname: Banys
authors.affiliation: Central Veterans Hospital, Lodz, Poland.
authors.forename: Joanna
authors.initials: J
authors.lastname: Latek
authors.affiliation: The Centre for Psychiatry at The Wolfson Institute for Preventive Medicine, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK.
authors.forename: Julius
authors.initials: J
authors.lastname: Bourke
authors.affiliation: Department of Cardiac Surgery, 1st Chair of Cardiology and Cardiac Surgery, Medical University of Lodz, Lodz, Poland.
authors.forename: Ryszard
authors.initials: R
authors.lastname: Jaszewski
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood; D002315:Cardiopulmonary Bypass / Q000009:adverse effects / Q000379:methods; D001026:Coronary Artery Bypass / Q000009:adverse effects / Q000379:methods; D003693:Delirium / Q000097:blood / Q000175:diagnosis / Q000209:etiology; D042241:Early Diagnosis; D005260:Female; D006801:Humans; D007376:Interleukin-2 / Q000097:blood*; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods; D017063:Outcome Assessment, Health Care; D011044:Poland; D011183:Postoperative Complications / Q000097:blood / Q000175:diagnosis; D011300:Preoperative Care / Q000379:methods; D011446:Prospective Studies; D011569:Psychiatric Status Rating Scales; D018570:Risk Assessment; D012307:Risk Factors; D014409:Tumor Necrosis Factor-alpha / Q000097:blood*
chemical_list: D015415:Biomarkers; D007376:Interleukin-2; D014409:Tumor Necrosis Factor-alpha