Impact of air pollution on hospital patients admitted with ST- and non-ST-segment elevation myocardial infarction in heavily polluted cities within the European Union

Background: Air pollution triggered diseases have become a leading health problem worldwide. The main adverse effects of air pollutants on human health are related to the cardiovascular system and particularly show an increasing prevalence of myocardial infarct and stroke. The aim of the study was to evaluate the influence of main air pollutants on non-ST-segment elevation myocardial infarction (NSTEMI) and ST-segment elevation myocardial infarction (STEMI) admissions to local interventional cardiology centers. Methods: Between 2014 and 2015, a midticenter registry of 1957 patients with acute myocardial infarction (STEMI, NSTEMI) admitted to interventional cardiology departments in three Polish cities were under investigation. The air pollution (PM2.5, PM10, NO2, SO2, O3) and weather conditions (temperature, barometric pressure, humidity) data for each city were collected as daily averages. The case-crossover design and conditional logistic regression were used to explore the association between acute myocardial infarctions and short-term air pollution exposure. Results: Occurrence of NSTEMI on the day of air pollution was triggered by PM2.5 (OR = 1.099, p = 0.01) and PM10 (OR = 1.078, p = 0.03). On the following day after the air pollution was recorded, NSTEMI was induced by: PM2.5 (OR = 1.093, p = 0.025), PM10 (OR = 1.077, p = 0.025) and SO2 (OR = 1.522, p = 0.009). For STEMI, events that occurred on the day in which air pollution was triggered by: PM2.5 (OR = 1.197, p < 0.001), PM10 (OR = 1.163, p < 0.001), SO2 (OR = 1.670, p = 0.001) and NO2 (OR = 1.287, p = 0.011). On the following day after air pollution was recorded, STEMI was induced by: PM2.5 (OR = 1.172, p < 0.001), PM10 (OR = 1.131, p = 0.001), SO2 (OR = 1.550, p = 0.005) and NO2 (OR = 1.265, p = 0.02). None of the weather conditions indicated were statistically significant for acute myocardial infarction occurrence. Conclusions: The most important pollutants triggering acute myocardial infarction occurrence in the population of southern Poland, both on the day of air pollution and the following day are particulate matters (PM2.5, PM10) and gaseous pollutants including NO2 and SO2. These pollutants should be regarded as modifiable risk factors and thus, their reduction is a priority in order to decrease total morbidity and mortality in Poland.