Associations of Air Pollution with Acute Coronary Syndromes Based on A/B/AB vs. O Blood Types – Case-crossover Study

Aims: : Short-term exposure to air pollutants may contribute to an increased risk of acute coronary syndrome (ACS). This study assessed the role of short-term exposure to fine particulate matter (PM 2.5 ) as well as fine and coarse PM (PM 10 ) air pollution in ACS events and the effect of blood groups on this phenomenon. Methods and Results: A retrospectively collected database of 9102 patients was evaluated. The study design was a case-crossover using a conditional logistic regression model. The main analysis focused on PM 2.5 levels with a 1 day lag until the ACS event, using threshold-modelled predictor for all patients. Secondary analyses utilized separate threshold-modelled predictors for 2 to 7-day moving averages and for patients from specific ABO blood groups. Additional analysis was performed with the non-threshold models and for PM 10 levels. Short-term exposure to increased PM 2.5 and PM 10 levels at a 1-day lag was associated with elevated risks of ACS (PM 2.5 OR= 1.012 per +10 µg/m 3 , 95% CI: 1.003, 1.021; PM 10 OR=1.014 per +10 µg/m 3 , CI: 1.002, 1.025) for all the patients. Analysis pointed out that exposure to PM 2.5 was associated with increased risk of ACS at a 1-day lag for the A, B or AB group (OR=1.012 per +10 µg/m 3 , CI: 1.001, 1.024), but not O group (OR=1.011 per +10 µg/m 3 , CI: 0.994, 1.029). Additional analysis showed positive association between exposure to PM 10 and risk of ACS and 7-day moving average models stratified by blood group revealed that exposure to PM 2.5 and PM 10 was associated with elevated risk of ACS for patients with group O. Conclusions: : Short-term exposure to PM 2.5 and PM 10 was associated with elevated risk of ACS. Short-term exposure to PM 2.5 was positively associated with the risk of ACS for patients with A, B, or AB blood groups for a 1-day lag, while risk in O group was delayed to 7 days. Translational Perspective: The study assessed association between increased levels of PM 2.5 and PM 10 and elevated risk of ACS. Outcomes can be useful for clinical medicine practitioners by taking into account possible risk factor of ACS which could be air quality.