title: Angiotensin receptor blockers and risk of myocardial infarction: systematic review.
abstract: OBJECTIVE
  To evaluate the effect of angiotensin receptor blockers on the risk of myocardial infarction in patients at risk for cardiovascular events.
  
  
  METHODS
  Systematic review of controlled trials of angiotensin receptor blockers.
  
  
  METHODS
  Medline, Embase, Cochrane central register of controlled trials, hand search, and contact with investigators.
  
  
  METHODS
  Predefined criteria were used to select controlled clinical trials comparing use of angiotensin receptor blockers with angiotensin converting enzyme (ACE) inhibitors or placebo in patients at risk for cardiovascular events. Data were extracted for patients' characteristics, interventions, quality of trials, and rates of myocardial infarction.
  
  
  RESULTS
  19 studies with 31,569 patients were included in the analysis. Two studies investigated the use of angiotensin receptor blockers in hypertensive patients, four studies in patients with diabetes and nephropathy, 10 studies in patients with heart failure, and three in patients with recent myocardial infarction or ischaemic syndrome. 11 studies of 21,062 patients allowed for comparison between angiotensin receptor blockers and placebo; nine studies of 10,625 patients allowed for comparison between angiotensin receptor blockers and ACE inhibitors. Use of angiotensin receptor blockers was not associated with increased risk of myocardial infarction compared with placebo (odds ratio 0.94, 95% confidence interval 0.75 to 1.16) nor with increased risk of myocardial infarction compared with ACE inhibitors (1.01, 0.87 to 1.16).
  
  
  CONCLUSIONS
  Treatment with angiotensin receptor blockers was not associated with a significantly increased risk of myocardial infarction. The 95% confidence intervals do, however, not exclude an increase of up to 16% in the risk of myocardial infarction or a reduction in risk of up to 25%. Until further information specifically dealing with this issue is available from large prospective trials, our findings may alleviate recent concerns over the safety of this class of medications.
authors.affiliation: Division of Cardiology, University of Alberta, 2C2 WMC, University of Alberta Hospital, 8440-112 Street, Edmonton, AB, Canada T6G 2B7.
authors.forename: Michael A
authors.initials: MA
authors.lastname: McDonald
authors.forename: Scot H
authors.initials: SH
authors.lastname: Simpson
authors.forename: Justin A
authors.initials: JA
authors.lastname: Ezekowitz
authors.forename: Gabor
authors.initials: G
authors.lastname: Gyenes
authors.forename: Ross T
authors.initials: RT
authors.lastname: Tsuyuki
mesh_terms: D000368:Aged; D047228:Angiotensin II Type 1 Receptor Blockers / Q000009:adverse effects*; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000009:adverse effects; D018849:Controlled Clinical Trials as Topic; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000139:chemically induced*; D016032:Randomized Controlled Trials as Topic; D012307:Risk Factors
chemical_list: D047228:Angiotensin II Type 1 Receptor Blockers; D000806:Angiotensin-Converting Enzyme Inhibitors