title: A history of smoking is associated with improved survival in patients treated with mild therapeutic hypothermia following cardiac arrest.
abstract: OBJECTIVE
  To assess the association between smoking and survival with a good neurologic outcome in patients following cardiac arrest treated with mild therapeutic hypothermia (TH).
  
  
  METHODS
  We conducted a retrospective observational study of a prospectively collected cohort of 188 consecutive patients following cardiac arrest treated with TH between May 2007 and January 2012. Smoking status was retrospectively collected via chart review and was classified as "ever" or "never". Primary endpoint was survival to hospital discharge with a good neurologic outcome and was compared between smokers and nonsmokers. Logistic regression analysis was used to assess the association between smoking status and neurologic outcome at hospital discharge; adjusting for age, initial rhythm, time to return of spontaneous circulation (ROSC), bystander CPR, and time to initiation of TH.
  
  
  RESULTS
  Smokers were significantly more likely to survive to hospital discharge with good neurologic outcome compared to nonsmokers (50% vs. 28%, p=0.003). After adjusting for age, initial rhythm, time to ROSC, bystander CPR, and time to initiation of TH, a history of smoking was associated with increased odds of survival to hospital discharge with good neurologic outcome (OR 3.54, 95% CI 1.41-8.84, p=0.007).
  
  
  CONCLUSIONS
  Smoking is associated with improved survival with good neurologic outcome in patients following cardiac arrest. We hypothesize that our findings reflect global ischemic conditioning caused by smoking.
authors.affiliation: Department of Internal Medicine, Vanderbilt University Medical Center, Nashville, TN, United States. Electronic address: Jeremy.s.pollock@vanderbilt.edu.
authors.forename: Jeremy S
authors.initials: JS
authors.lastname: Pollock
authors.affiliation: Division of Cardiovascular Medicine, Vanderbilt University Medical Center, Nashville, TN, United States.
authors.forename: Ryan D
authors.initials: RD
authors.lastname: Hollenbeck
authors.affiliation: Department of Biostatistics, Vanderbilt University Medical Center, Nashville, TN, United States.
authors.forename: Li
authors.initials: L
authors.lastname: Wang
authors.affiliation: Division of Allergy, Pulmonary and Critical Care Medicine, Vanderbilt University Medical Center, Nashville, TN, United States.
authors.forename: David R
authors.initials: DR
authors.lastname: Janz
authors.affiliation: Division of Allergy, Pulmonary and Critical Care Medicine, Vanderbilt University Medical Center, Nashville, TN, United States.
authors.forename: Todd W
authors.initials: TW
authors.lastname: Rice
authors.affiliation: Division of Cardiovascular Medicine, Vanderbilt University Medical Center, Nashville, TN, United States.
authors.forename: John A
authors.initials: JA
authors.lastname: McPherson
mesh_terms: D000368:Aged; D005260:Female; D006323:Heart Arrest / Q000401:mortality* / Q000628:therapy*; D006801:Humans; D007036:Hypothermia, Induced / Q000379:methods; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012907:Smoking; D015996:Survival Rate; D016896:Treatment Outcome
keywords: Cardiac arrest; Post-resuscitation care; Smoking; Therapeutic hypothermia
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