The exposure-response relationship between air pollution and acute myocardial infarction

Abstract

Short-term exposure to air pollutants has been associated with cardiovascular disease. Moreover, previous study suggested that the exposure-response function is relatively steep at low levels of exposure, flattening out at high exposure levels. This study assessed the shape of the exposure-response relationship between air pollution and acute myocardial infarction (MI).Data on emergency departments (ED) visits case of acute MI in seven metropolitan cities (Seoul, Busan, Incheon, Daegu, Daejeon, Gwanguju and Ulsan, Republic of Korea) were obtained from the Health Insurance Review and Assessment Service (HIRA) from 2005 to 2008. A time-stratified case-crossover and generalized additive model (time series) were applied to examine the impact of air pollution on acute MI. And, exposure-response curve and change point estimated from Markov chain Monte Carlo (MCMC) method. To evaluate immediate and delayed effects of air pollutants, we used both single-lag and distributed-lag models.All air pollutants, with the exception of PM10 and O3, were significantly associated with an increased risk of acute MI in case-crossover and time series analyses. Our results suggest that there are subgroups in the population (the elderly, females, patients with cardiopulmonary comorbidity) that are more susceptible to airborne pollutants. And the exposure–response relation showed at very low levels of exposure except PM10.In conclusion, this study adds further evidence for an association between short-term increases in air pollutant levels and acute MI and the exposure-response relationships have important public health implications.