Air pollution and out-of-hospital cardiac arrest risk

Background Globally nearly 20% of cardiovascular disease deaths were attributable to air pollution. Out-of-hospital cardiac arrest (OHCA) represents a major public health problem, therefore, the identification of novel OHCA triggers is of crucial relevance. The aim of the study was to evaluate the association between air pollution (short-, mid-and long-term exposure) and out-of-hospital cardiac arrest (OHCA) risk, during a 7 years-period from a highly polluted urban area with a high density of automated external defibrillators (AEDs). Methods and results OHCA were prospectively collected from the “Progetto Vita Database” between 01/01/2010 to 31/12/2017; day-by-day air pollution levels were extracted from the Environmental Protection Agency (ARPA) stations. Electrocardiograms of OHCA interventions were collected from the AEDs data cards. Day-by-day particulate matter (PM) 2.5 and 10, ozone (O3), carbon monoxide (CO) and nitrogen dioxide (NO2) levels were measured. A total of 880 OHCAs occurred in 748 days. A significantly increased in OHCA risk with the progressive increase in PM 2.5, PM 10, CO and NO2 levels was found. After adjustment for temperature and seasons, a 9% and 12% increase of OHCA risk for each 10 μg/m3 increase of PM 10 (p< 0.0001) and PM 2.5 (p< 0.0001) levels was found. Air pollutants levels were associated with both asystole and shockable rhythm risk while no correlation was found with pulseless electrical activity. Conclusions Short-term and mid-term exposure to PM 2.5 and PM 10 is independently associated with the risk of OHCA due to asystole or shockable rhythm. ### Competing Interest Statement The authors have declared no competing interest. ### Clinical Trial None ### Funding Statement This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Not Applicable The details of the IRB/oversight body that provided approval or exemption for the research described are given below: Approved by the ethics committee of Area Vasta Emilia Nord, Italy I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Not Applicable I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Not Applicable I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Not Applicable The data that support the findings of this study are available from the corresponding author, upon reasonable request.