Rising Ozone Levels Increase Risk of Heart Attack

Rising ozone levels due to air pollution are increasing the risk of heart attacks, A study finds.

Air pollution and rising ozone levels are increasing the risk of heart attacks among young people. A study published in the GeoHealth journal found that high levels of air pollution contribute to the risk of heart attacks. However, it remains unclear how these risks vary based on demographics, types of air pollution, and types of heart attacks.

The study examined data from 2,322 patients aged 18 to 55 in the United States, with nearly 70% of them being women. Researchers analyzed the correlation between heart attack incidents and concurrent levels of ozone and fine particulate matter (PM2.5) around the patients’ homes. Different types of heart attacks were classified separately in the study.

Types of Heart Attacks:

• Type 1 Heart Attacks: Caused by the formation of blood clots.
• Type 2 Heart Attacks: Occur due to conditions like low blood pressure, which reduce oxygen supply without forming clots.
• ST-Elevation Myocardial Infarction (STEMI): Happens when a fully blocked artery stops blood flow, leading to a distinctive electrocardiogram (ECG) pattern.

The GeoHealth journal study found that high levels of air pollution are a significant contributor to heart attack risks. However, variations in risk based on demographics, air pollution type, and heart attack type remain unclear. Researchers examined heart attack incidents alongside ozone and fine particulate matter levels near patients’ homes.

Key Findings:

• High ozone levels were linked to an increase in heart attacks four to five days later.
• No correlation was found between fine particulate matter levels and heart attacks.
• Ozone levels were strongly associated with Type 2 heart attacks and non-STEMI heart attacks but showed no connection with STEMI heart attacks.
• Among non-Hispanic Black patients, the correlation between high ozone levels and heart attacks was stronger compared to non-Hispanic white patients.
• A significant relationship between ozone levels and heart attacks was found even when ozone levels were below the World Health Organization’s recommended limits.

The study’s findings contradict some previous research. For example, it indicates a link between air pollution and non-STEMI heart attacks but finds no association between fine particulate matter and heart attacks. Additionally, the analysis revealed a slightly stronger correlation between ozone levels and heart attacks during warmer months compared to colder months, though the statistical significance was low.

Researchers also suggested that under climate change scenarios, the frequency of heart attacks might increase. When a partially blocked artery reduces blood flow without causing STEMI, similar ECG changes can occur.