title: Duration of preoperative β-blockade and outcomes after major elective noncardiac surgery.
abstract: BACKGROUND
  Although practice guidelines recommend that perioperative β-blockade be initiated at least several days to weeks before noncardiac surgery is performed, the minimum required period of preoperative therapy is unclear.
  
  
  METHODS
  Population-based administrative databases were used to conduct a cohort study of 48,103 patients aged ≥ 66 years who underwent major elective noncardiac surgery in Ontario, Canada and received preoperative β-blocker therapy. We used multivariable logistic regression to determine the association of duration of preoperative β-blocker treatment (classified as 1-7 days, 8-30 days, and ≥ 31 days) with 30-day mortality, 30-day myocardial infarction (MI), 30-day ischemic stroke, and 1-year mortality.
  
  
  RESULTS
  The duration of preoperative β-blocker treatment was 1-7 days in 1105 patients (2.3%), 8-30 days in 2639 patients (5.5%), and ≥ 31 days in 44,269 patients (92.0%). Compared with ≥ 31 days of preoperative therapy, 1-7 days of therapy was associated with increased 30-day mortality (odds ratio [OR], 1.49; 95% confidence interval [CI], 1.03-2.16; P = 0.03], whereas 8-30 days of therapy was not (OR, 0.95; 95% CI, 0.69-1.31; P = 0.77). One to 7 days of preoperative therapy was not significantly associated with 1-year mortality (OR, 1.06; 95% CI, 0.84-1.35; P = 0.62), 30-day MI (OR, 1.26; 95% CI, 0.92-1.71; P = 0.15), or 30-day ischemic stroke (OR, 1.37; 95% CI, 0.64-2.94; P = 0.41).
  
  
  CONCLUSIONS
  Initiation of β-blocker therapy 1-7 days before noncardiac surgery is associated with increased 30-day mortality. The findings merit further evaluation by randomized trials.
authors.affiliation: Li Ka Shing Knowledge Institute of St Michael's Hospital, Toronto, Ontario, Canada; Department of Anesthesia, Toronto General Hospital and University of Toronto, Toronto, Ontario, Canada; Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada; Institute of Health Policy Management and Evaluation, University of Toronto, Toronto, Ontario, Canada. Electronic address: d.wijeysundera@utoronto.ca.
authors.forename: Duminda N
authors.initials: DN
authors.lastname: Wijeysundera
authors.affiliation: Department of Anesthesia, Toronto General Hospital and University of Toronto, Toronto, Ontario, Canada.
authors.forename: W Scott
authors.initials: WS
authors.lastname: Beattie
authors.affiliation: Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada; Institute of Health Policy Management and Evaluation, University of Toronto, Toronto, Ontario, Canada; Division of Cardiology, Schulich Heart Centre, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Harindra C
authors.initials: HC
authors.lastname: Wijeysundera
authors.affiliation: Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada.
authors.forename: Lingsong
authors.initials: L
authors.lastname: Yun
authors.affiliation: Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada; Institute of Health Policy Management and Evaluation, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Peter C
authors.initials: PC
authors.lastname: Austin
authors.affiliation: Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada; Institute of Health Policy Management and Evaluation, University of Toronto, Toronto, Ontario, Canada; Division of Cardiology, Schulich Heart Centre, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Dennis T
authors.initials: DT
authors.lastname: Ko
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage*; D000368:Aged; D004334:Drug Administration Schedule; D017558:Elective Surgical Procedures; D005260:Female; D005500:Follow-Up Studies; D006323:Heart Arrest / Q000401:mortality / Q000517:prevention & control*; D006801:Humans; D015994:Incidence; D008297:Male; D009864:Ontario / Q000453:epidemiology; D011183:Postoperative Complications / Q000453:epidemiology / Q000517:prevention & control*; D011300:Preoperative Care / Q000379:methods*; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000319:Adrenergic beta-Antagonists