title: Physical Activity and Anger or Emotional Upset as Triggers of Acute Myocardial Infarction: The INTERHEART Study.
abstract: BACKGROUND
  Physical exertion, anger, and emotional upset are reported to trigger acute myocardial infarction (AMI). In the INTERHEART study, we explored the triggering association of acute physical activity and anger or emotional upset with AMI to quantify the importance of these potential triggers in a large, international population.
  
  
  METHODS
  INTERHEART was a case-control study of first AMI in 52 countries. In this analysis, we included only cases of AMI and used a case-crossover approach to estimate odds ratios for AMI occurring within 1 hour of triggers.
  
  
  RESULTS
  Of 12 461 cases of AMI 13.6% (n=1650) engaged in physical activity and 14.4% (n=1752) were angry or emotionally upset in the case period (1 hour before symptom onset). Physical activity in the case period was associated with increased odds of AMI (odds ratio, 2.31; 99% confidence interval [CI], 1.96-2.72) with a population-attributable risk of 7.7% (99% CI, 6.3-8.8). Anger or emotional upset in the case period was associated with an increased odds of AMI (odds ratio, 2.44; 99% CI, 2.06-2.89) with a population-attributable risk of 8.5% (99% CI, 7.0-9.6). There was no effect modification by geographical region, prior cardiovascular disease, cardiovascular risk factor burden, cardiovascular prevention medications, or time of day or day of onset of AMI. Both physical activity and anger or emotional upset in the case period were associated with a further increase in the odds of AMI (odds ratio, 3.05; 99% CI, 2.29-4.07; P for interaction <0.001).
  
  
  CONCLUSIONS
  Physical exertion and anger or emotional upset are triggers associated with first AMI in all regions of the world, in men and women, and in all age groups, with no significant effect modifiers.
authors.affiliation: From Population Health Research Institute, Hamilton Health Sciences and McMaster University, Hamilton, ON, Canada (A.S., M.O., P.L., K.T., S.R., S.Y.); and HRB Clinical Research Facility Galway, National University of Ireland Galway, Galway, Ireland (A.S., M.O.).
authors.forename: Andrew
authors.initials: A
authors.lastname: Smyth
authors.affiliation: From Population Health Research Institute, Hamilton Health Sciences and McMaster University, Hamilton, ON, Canada (A.S., M.O., P.L., K.T., S.R., S.Y.); and HRB Clinical Research Facility Galway, National University of Ireland Galway, Galway, Ireland (A.S., M.O.).
authors.forename: Martin
authors.initials: M
authors.lastname: O'Donnell
authors.affiliation: From Population Health Research Institute, Hamilton Health Sciences and McMaster University, Hamilton, ON, Canada (A.S., M.O., P.L., K.T., S.R., S.Y.); and HRB Clinical Research Facility Galway, National University of Ireland Galway, Galway, Ireland (A.S., M.O.).
authors.forename: Pablo
authors.initials: P
authors.lastname: Lamelas
authors.affiliation: From Population Health Research Institute, Hamilton Health Sciences and McMaster University, Hamilton, ON, Canada (A.S., M.O., P.L., K.T., S.R., S.Y.); and HRB Clinical Research Facility Galway, National University of Ireland Galway, Galway, Ireland (A.S., M.O.).
authors.forename: Koon
authors.initials: K
authors.lastname: Teo
authors.affiliation: From Population Health Research Institute, Hamilton Health Sciences and McMaster University, Hamilton, ON, Canada (A.S., M.O., P.L., K.T., S.R., S.Y.); and HRB Clinical Research Facility Galway, National University of Ireland Galway, Galway, Ireland (A.S., M.O.).
authors.forename: Sumathy
authors.initials: S
authors.lastname: Rangarajan
authors.affiliation: From Population Health Research Institute, Hamilton Health Sciences and McMaster University, Hamilton, ON, Canada (A.S., M.O., P.L., K.T., S.R., S.Y.); and HRB Clinical Research Facility Galway, National University of Ireland Galway, Galway, Ireland (A.S., M.O.). salim.yusuf@phri.ca.
authors.forename: Salim
authors.initials: S
authors.lastname: Yusuf
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000786:Anger / Q000502:physiology*; D016022:Case-Control Studies; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000453:epidemiology* / Q000209:etiology*; D016017:Odds Ratio; D005082:Physical Exertion; D012307:Risk Factors; D013997:Time Factors
keywords: epidemiology; myocardial infarction; precipitating factors