title: Predictors of early and late stroke following cardiac surgery.
abstract: BACKGROUND
  Much is known about the short-term risks of stroke following cardiac surgery. We examined the rate and predictors of long-term stroke in a cohort of patients who underwent cardiac surgery.
  
  
  METHODS
  We obtained linked data for patients who underwent cardiac surgery in the province of Ontario between 1996 and 2006. We analyzed the incidence of stroke and death up to 2 years postoperatively.
  
  
  RESULTS
  Of 108,711 patients, 1.8% (95% confidence interval [CI] 1.7%-1.9%) had a stroke perioperatively, and 3.6% (95% CI 3.5%-3.7%) had a stroke within the ensuing 2 years. The strongest predictors of both early and late stroke were advanced age (≥ 65 year; adjusted hazard ratio [HR] for all stroke 1.9, 95% CI 1.8-2.0), a history of stroke or transient ischemic attack (adjusted HR 2.1, 95% CI 1.9-2.3), peripheral vascular disease (adjusted HR 1.6, 95% CI 1.5-1.7), combined coronary bypass grafting and valve surgery (adjusted HR 1.7, 95% CI 1.5-1.8) and valve surgery alone (adjusted HR 1.4, 95% CI 1.2-1.5). Preoperative need for dialysis (adjusted odds ratio [OR] 2.1, 95% CI 1.6-2.8) and new-onset postoperative atrial fibrillation (adjusted OR 1.5, 95% CI 1.3-1.6) were predictors of only early stroke. A CHADS2 score of 2 or higher was associated with an increased risk of stroke or death compared with a score of 0 or 1 (19.9% v. 9.3% among patients with a history of atrial fibrillation, 16.8% v. 7.8% among those with new-onset postoperative atrial fibrillation and 14.8% v. 5.8% among those without this condition).
  
  
  CONCLUSIONS
  Patients who had cardiac surgery were at highest risk of stroke in the early postoperative period and had continued risk over the ensuing 2 years, with similar risk factors over these periods. New-onset postoperative atrial fibrillation was a predictor of only early stroke. The CHADS2 score predicted stroke risk among patients with and without atrial fibrillation.
authors.affiliation: Population Health Research Institute and McMaster University (Whitlock, Healey, Connolly, Teoh, Khera, Yusuf), Hamilton, Ont.; Sunnybrook Schulich Heart Centre (Tu, Fremes), University of Toronto, Toronto, Ont.; Institute for Clinical Evaluative Sciences (Wang, Tu), Toronto, Ont.; Vanderbilt University (Danter), Nashville, Tenn.; London Health Sciences Centre (Novick), London, Ont.
authors.forename: Richard
authors.initials: R
authors.lastname: Whitlock
authors.affiliation: Population Health Research Institute and McMaster University (Whitlock, Healey, Connolly, Teoh, Khera, Yusuf), Hamilton, Ont.; Sunnybrook Schulich Heart Centre (Tu, Fremes), University of Toronto, Toronto, Ont.; Institute for Clinical Evaluative Sciences (Wang, Tu), Toronto, Ont.; Vanderbilt University (Danter), Nashville, Tenn.; London Health Sciences Centre (Novick), London, Ont.
authors.forename: Jeff S
authors.initials: JS
authors.lastname: Healey
authors.affiliation: Population Health Research Institute and McMaster University (Whitlock, Healey, Connolly, Teoh, Khera, Yusuf), Hamilton, Ont.; Sunnybrook Schulich Heart Centre (Tu, Fremes), University of Toronto, Toronto, Ont.; Institute for Clinical Evaluative Sciences (Wang, Tu), Toronto, Ont.; Vanderbilt University (Danter), Nashville, Tenn.; London Health Sciences Centre (Novick), London, Ont.
authors.forename: Stuart J
authors.initials: SJ
authors.lastname: Connolly
authors.affiliation: Population Health Research Institute and McMaster University (Whitlock, Healey, Connolly, Teoh, Khera, Yusuf), Hamilton, Ont.; Sunnybrook Schulich Heart Centre (Tu, Fremes), University of Toronto, Toronto, Ont.; Institute for Clinical Evaluative Sciences (Wang, Tu), Toronto, Ont.; Vanderbilt University (Danter), Nashville, Tenn.; London Health Sciences Centre (Novick), London, Ont.
authors.forename: Julie
authors.initials: J
authors.lastname: Wang
authors.affiliation: Population Health Research Institute and McMaster University (Whitlock, Healey, Connolly, Teoh, Khera, Yusuf), Hamilton, Ont.; Sunnybrook Schulich Heart Centre (Tu, Fremes), University of Toronto, Toronto, Ont.; Institute for Clinical Evaluative Sciences (Wang, Tu), Toronto, Ont.; Vanderbilt University (Danter), Nashville, Tenn.; London Health Sciences Centre (Novick), London, Ont.
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Danter
authors.affiliation: Population Health Research Institute and McMaster University (Whitlock, Healey, Connolly, Teoh, Khera, Yusuf), Hamilton, Ont.; Sunnybrook Schulich Heart Centre (Tu, Fremes), University of Toronto, Toronto, Ont.; Institute for Clinical Evaluative Sciences (Wang, Tu), Toronto, Ont.; Vanderbilt University (Danter), Nashville, Tenn.; London Health Sciences Centre (Novick), London, Ont.
authors.forename: Jack V
authors.initials: JV
authors.lastname: Tu
authors.affiliation: Population Health Research Institute and McMaster University (Whitlock, Healey, Connolly, Teoh, Khera, Yusuf), Hamilton, Ont.; Sunnybrook Schulich Heart Centre (Tu, Fremes), University of Toronto, Toronto, Ont.; Institute for Clinical Evaluative Sciences (Wang, Tu), Toronto, Ont.; Vanderbilt University (Danter), Nashville, Tenn.; London Health Sciences Centre (Novick), London, Ont. richard.whitlock@phri.ca.
authors.forename: Richard
authors.initials: R
authors.lastname: Novick
authors.affiliation: Population Health Research Institute and McMaster University (Whitlock, Healey, Connolly, Teoh, Khera, Yusuf), Hamilton, Ont.; Sunnybrook Schulich Heart Centre (Tu, Fremes), University of Toronto, Toronto, Ont.; Institute for Clinical Evaluative Sciences (Wang, Tu), Toronto, Ont.; Vanderbilt University (Danter), Nashville, Tenn.; London Health Sciences Centre (Novick), London, Ont.
authors.forename: Stephen
authors.initials: S
authors.lastname: Fremes
authors.affiliation: Population Health Research Institute and McMaster University (Whitlock, Healey, Connolly, Teoh, Khera, Yusuf), Hamilton, Ont.; Sunnybrook Schulich Heart Centre (Tu, Fremes), University of Toronto, Toronto, Ont.; Institute for Clinical Evaluative Sciences (Wang, Tu), Toronto, Ont.; Vanderbilt University (Danter), Nashville, Tenn.; London Health Sciences Centre (Novick), London, Ont.
authors.forename: Kevin
authors.initials: K
authors.lastname: Teoh
authors.affiliation: Population Health Research Institute and McMaster University (Whitlock, Healey, Connolly, Teoh, Khera, Yusuf), Hamilton, Ont.; Sunnybrook Schulich Heart Centre (Tu, Fremes), University of Toronto, Toronto, Ont.; Institute for Clinical Evaluative Sciences (Wang, Tu), Toronto, Ont.; Vanderbilt University (Danter), Nashville, Tenn.; London Health Sciences Centre (Novick), London, Ont.
authors.forename: Vikas
authors.initials: V
authors.lastname: Khera
authors.affiliation: Population Health Research Institute and McMaster University (Whitlock, Healey, Connolly, Teoh, Khera, Yusuf), Hamilton, Ont.; Sunnybrook Schulich Heart Centre (Tu, Fremes), University of Toronto, Toronto, Ont.; Institute for Clinical Evaluative Sciences (Wang, Tu), Toronto, Ont.; Vanderbilt University (Danter), Nashville, Tenn.; London Health Sciences Centre (Novick), London, Ont.
authors.forename: Salim
authors.initials: S
authors.lastname: Yusuf
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D006348:Cardiac Surgical Procedures; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009864:Ontario; D011183:Postoperative Complications / Q000453:epidemiology / Q000209:etiology*; D016016:Proportional Hazards Models; D012307:Risk Factors; D020521:Stroke / Q000453:epidemiology / Q000209:etiology*; D055815:Young Adult