title: Risk of neuroleptic malignant syndrome in patients with bipolar disorder: a retrospective, population-based case-control study.
abstract: BACKGROUND
  Current data regarding risk factors of neuroleptic malignant syndrome (NMS) are limited. This study aims to examine factors associated with increased risk of NMS in patients with bipolar disorder.
  
  
  METHODS
  A retrospective, population-based, case-control study was performed using a medical claims database covering January 1998 to December 2002. Fifty cases with a diagnosis of NMS were identified and matched with 800 controls. Conditional logistic regression analysis was used to estimate crude and adjusted odds ratios (ORs) of risk of NMS.
  
  
  RESULTS
  Antipsychotic use was associated with an increased risk of NMS after controlling for other pharmacologic and clinical factors (OR = 2.36, 95% CI = 1.08-5.19). Other factors associated with an increased risk of NMS included being male (OR = 2.07, 95% CI = 1.07-4.02), confusion (OR = 2.91, 95% CI = 1.17-7.28), dehydration (OR = 3.99, 95% CI = 1.50-10.57), delirium (OR = 4.93, 95% CI = 2.07-11.72), and extrapyramidal symptoms (OR = 3.50, 95% CI = 1.10-11.09).
  
  
  CONCLUSIONS
  Given the widespread use of antipsychotics for the treatment of bipolar disorder, clinicians should be vigilant of the potential pharmacologic and clinical factors associated with increased risk of NMS in patients with bipolar disorder.
authors.affiliation: Department of Pharmacy Practice and Administrative Sciences, School of Pharmacy, University of Cincinnati Medical Center, Ohio 45267-0004, USA. yance@email.uc.edu
authors.forename: Yan
authors.initials: Y
authors.lastname: Chen
authors.forename: Jeff J
authors.initials: JJ
authors.lastname: Guo
authors.forename: Michael
authors.initials: M
authors.lastname: Steinbuch
authors.forename: Peter F
authors.initials: PF
authors.lastname: Buckley
authors.forename: Nick C
authors.initials: NC
authors.lastname: Patel
mesh_terms: D000328:Adult; D000368:Aged; D014150:Antipsychotic Agents / Q000009:adverse effects* / Q000627:therapeutic use; D001714:Bipolar Disorder / Q000188:drug therapy* / Q000453:epidemiology*; D016022:Case-Control Studies; D015897:Comorbidity; D003430:Cross-Sectional Studies; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D008297:Male; D008329:Managed Care Programs / Q000706:statistics & numerical data; D008875:Middle Aged; D009459:Neuroleptic Malignant Syndrome / Q000175:diagnosis* / Q000453:epidemiology*; D012189:Retrospective Studies; D012306:Risk; D014481:United States
chemical_list: D014150:Antipsychotic Agents