Burden and economic impact of PM2.5 exposure on Acute Myocardial Infarction in Portugal, 2011-2021

Abstract Background Air pollution, specifically particulate matter with a diameter of 2.5 micrometers (PM2.5), is the primary environmental health risk in Europe. Exposure to PM2.5 increases the risk of cardiovascular diseases, including AMI, resulting in high direct costs associated with in-patient treatment. This study aims to estimate the avoidable and attributable disease and economic burden of AMI due to ambient PM2.5 exposure in Portugal between 2011 and 2021. Methods National databases were used to assess the annual number of hospitalisations and deaths due to AMI between 2011 and 2021. The annual mean costs were calculated using a direct cost analysis (bottom-up micro-costing) to assess the direct economic burden of AMI. In turn, these cases and associated costs were multiplied by the respective morbidity and mortality population attributable fraction (PAF) to estimate the number of hospital admissions and deaths, and their associated costs attributable to ambient PM2.5 exposure. For 2019 and 2021, an alternative scenario of exposure was considered (2021 WHO Air Quality Guidelines), and the avoidable morbidity and mortality costs were determined using the potential impact fraction (PIF). Results Between 2011 and 2021, there were 130,447 hospitalisations and 47,968 deaths due to AMI, with 4.79% and 28.90%, respectively, attributable to ambient PM2.5 exposure. This translates to a direct economic burden of morbidity of more than 44 million euros and mortality of almost 195 million euros. If the proposed scenario guidelines were met, 279 cases and 448 deaths would have been avoided in 2019, resulting in a savings of almost 9.7 million euros. In 2021, 93 cases and 355 deaths would have been avoided, with approximately 4 million euros saved. Conclusions Exposure to ambient PM2.5 significantly contributes to AMI cases and deaths in Portugal, imposing a significant economic burden. These findings highlight the urgent need for measures to improve air quality. Key messages • PM2.5 pollution in Portugal drives AMI cases and fatalities, entailing significant economic costs. • Adhering to WHO air quality guidelines promises substantial reductions in AMI incidence and save millions annually in healthcare expenditure.