Exposure to air pollution-a trigger for myocardial infarction? A nine-year study in Bialystok-the capital of the Green Lungs of Poland (BIA-ACS registry).

Objectives: This study aimed to assess the effect of air pollution and weather conditions on the frequency of hospital admissions due to acute coronary syndrome (ACS) in the population of Bialystok, known as the capital of the Green Lungs of Poland.

Materials And Methods: The study analyzed the medical records of 2,645 patients living within the borders of Bialystok who were treated for ACS between 2009 and 2017 and the data on air pollutants-nitrogen dioxide (NO), sulfur dioxide (SO), and particulate matter with a diameter of 2.5 μm or less (PM) and 10 μm or less (PM)-and the basic meteorological factors (temperature, humidity, and atmospheric pressure). A time-stratified case-crossover study design was applied to assess the effects of particulate matter, the concentration of gases, and weather conditions on ACS.

Results: The number of patients admitted for ST-segment elevation myocardial infarction, non-ST-segment elevation myocardial infarction (NSTEMI), and unstable angina (UA) was 791, 999, and 855, respectively. The daily concentration norm for PM recommended by the World Health Organization (WHO) was exceeded in 692 days (i.e., 24.58% of the observation period). The significant increase in the number of ACS hospitalizations was associated with an interquartile-range increase in NO concentration, with an odds ratio of 1.08 (95% confidence interval (CI): 1.02-1.15, P = 0.01), 1.09 (95% CI: 1.01-1.18, P = 0.03), and 1.11 (95% CI: 1.00-1.22, P = 0.048) for patients with ACS, NSTEMI, and UA, respectively.

Conclusion: The study showed that the effects of air pollution and weather conditions on the number of ACS hospitalizations are also observed in cities with moderately polluted or good air quality. NO was identified as the main air pollutant affecting the incidence of ACS.