Environmental triggers of acute myocardial infarction: does air pollution matter?

Purpose: Exposure to air pollution has been shown to be a trigger of acute myocardial infarction (AMI). As in those studies no correction was made for other meteorological factors, the present study wants to evaluate the independent environmental triggers of AMI. Methods: Weekly counts of AMI patients that underwent primary percutaneous coronary intervention (pPCI) in the period 2006-2009 in 32 Belgian PCI centres were extracted from the national PCI database. Those data were correlated with average weekly meteorological data obtained from daily measurements in 73 meteorological sites, equally distributed in Belgium. The following meteorological measures were investigated: air pollution expressed as particulate matter both less than 10μM (PM10) and less than 2.5μM (PM2.5), black smoke, temperature and relative humidity. Time-series and Poisson regression analysis were carried out to investigate the correlation between environmental changes and the incidence of AMI. Results: During the study period a total of 15964 AMI patients (mean age 63, 24.8% female) were admitted with a weekly average admission rate of 77±11 patients. Time-series (see figure) and univariate Poisson regression revealed a significant positive correlation between AMI's and air pollution and an inverse correlation between AMI's and temperature. Multivariate analysis showed that only low temperature was significantly correlated with AMI with an increase of 7% AMI's for each 10°C decrease in minimal temperature (0R 1.07 95% CI 1.04-1.11.) and that there was no significant effect of air pollution (0R 1.01 95% CI 1.00-1.02). ![Figure][1] time series Conclusions: In a global environmental model, low temperature is by far the most important environmental trigger for AMI, whereas air pollution has a negligible effect. [1]: pending:yes