title: Environmental triggers of acute myocardial infarction: results of a nationwide multiple-factorial population study.
abstract: OBJECTIVE
  The objective of this study was to study the independent environmental triggers of ST-elevation myocardial infarction (STEMI) in a multifactorial environmental population model.
  
  
  RESULTS
  Daily counts of all STEMI patients who underwent urgent percutaneous coronary intervention over the period 2006-2009 in Belgium were associated with average daily meteorological data and influenza-like illness incidence data. The following meteorological measures were investigated: particulate matter less than 10 μM (PM10) and less than 2.5 μM (PM(2.5)), ozone, black smoke, temperature and relative humidity. During the study period a total of 15,964 STEMI patients (mean age 63, 75% male) were admitted with a daily average admission rate of 11 ± 4 patients. A multivariate Poisson regression analysis showed that only the temperature was significantly correlated with STEMI, with an 8% increase in the risk of STEMI for each 10°C decrease in temperature (adjusted incidence risk ratio (IRR) 0.92, 95% CI 0.89-0.96). The effects of temperature were consistent among several subpopulations but the strongest effect was seen in diabetic patients (IRR 0.85, 95% CI 0.78 -0.95). There was a trend for an incremental risk of STEMI for each 10 μg/m³ PM(2.5) increase and during influenza epidemics with IRR of 1.02 (95% CI 1.00-1.04) and 1.07 (95% CI 0.98-1.16), respectively.
  
  
  CONCLUSIONS
  In a global environmental model, low temperature is the most important environmental trigger for STEMI, whereas air pollution and influenza epidemics only seem to have a modest effect.
authors.forename: Marc J
authors.initials: MJ
authors.lastname: Claeys
authors.forename: Sarah
authors.initials: S
authors.lastname: Coenen
authors.forename: Charlotte
authors.initials: C
authors.lastname: Colpaert
authors.forename: Joke
authors.initials: J
authors.lastname: Bilcke
authors.forename: Phillip
authors.initials: P
authors.lastname: Beutels
authors.forename: Kristien
authors.initials: K
authors.lastname: Wouters
authors.forename: Victor
authors.initials: V
authors.lastname: Legrand
authors.forename: Pierre
authors.initials: P
authors.lastname: Van Damme
authors.forename: Christiaan
authors.initials: C
authors.lastname: Vrints
mesh_terms: D000368:Aged; D001530:Belgium / Q000453:epidemiology; D004562:Electrocardiography; D004781:Environmental Exposure / Q000009:adverse effects*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000453:epidemiology / Q000209:etiology* / Q000601:surgery; D062645:Percutaneous Coronary Intervention / Q000379:methods; D011159:Population Surveillance / Q000379:methods*; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D015996:Survival Rate / Q000639:trends
keywords: Myocardial infarction; epidemiology; population; risk factor