High Ozone Exposure Linked To Increased Cardiac Arrest Risk: Study

Exposure to high levels of ozone air pollution may increase the risk of cardiac arrest, according to the findings of new research.

In a study scheduled to be presented next week at the American Heart Association Resuscitation Science Symposium, researchers with Saint Luke’s Mid America Heart Institute indicate that ozone exposure not only increases the risk of cardiac arrest, but as exposure increased the risk level also increased.

Researchers conducted an analysis of 187,000 patients with non-traumatic out-of-hospital cardiac arrest from 2013-2016. Participants were ages 63 years on average. Cardiac arrest is life threatening and can lead to death. It requires emergency medical attention.

Individual exposures to particulate matter and ozone were estimated using data from the U.S. Environmental Protection Agency’s (EPA) atmospheric models that predict daily ozone levels. Researchers also used data from the Cardiac Arrest Registry to Enhance Survival to connect incidence of cardiac arrest and examine if higher concentrations of ozone and particulate matter were a potential factor.

According to the findings, for every 12 parts per billion (ppb) increase in ozone levels, the risk of cardiac arrest increased by 1%, which was considered statistically significant by researchers.

There was no link between increased particulate matter concentrations and risk of cardiac arrest, nor was there a difference in the risk for air-quality-related cardiac arrest tied to age, sex, or race.

Researchers also found higher concentrations of ozone on the day patients experienced out-of-hospital cardiac arrest was linked to an increased risk overall. The link between cardiac arrest and levels of ozone exposure were found even at levels below EPA air quality safety standards.

Prior studies have shown exposure to air pollution, in particular, ozone and particulate matter, are linked to the development of chronic diseases, including increased risk of stroke and emphysema after long-term exposure. Exposure to air pollution during pregnancy can lead to silent miscarriage and exposure during childhood increases the risk of the child suffering from asthma and other respiratory issues.

Research published in 2017 found that exposure even at levels below national safety standards increase the risk of early death and a study published earlier this year indicated even at short-term exposure, air pollution can increase the risk of cardiac arrest.

Authors of the new study emphasize the importance of limiting exposure to high ozone levels and call for more aggressive regulation to decrease ambient air ozone concentrations.

This is an observational study and exposure was taken form outdoor estimates. Further research is needed to determine the exact link between increased risk of cardiac arrest from air pollution exposure.

The study findings are considered preliminary research and will be presented at the American Heart Association’s Resuscitation Science Symposium 2020, a virtual meeting scheduled for November 14-16.