Air Pollution Spikes As Harmful for Heart As Long-Term Exposure: Study

Rapid increases in air pollution may double the rate of heart problems among area residents, according to the findings of a new study, which suggests that air pollution spikes may be just as harmful as long-term exposure. 

In a study published last week in the medical journal The BMJ, researchers from London evaluated concentrations of air pollutants during the days and weeks surrounding heart attacks that occurred over a seven year period around one hospital.

The risk air pollution poses to heart health has been known for some time. A study published in 2016 long-term exposure to air pollution, even at low levels, increased a person’s risk of heart disease and increased their risk of early death. One study indicated the risk was due to damage to the blood vessels due to inflammation after exposure.

Another study linked air pollution exposure to an increased risk of  stroke and hospitalization after stroke. Yet, researchers believed sustained high levels of air pollution were the culprit. The new study indicates spikes in air pollution, even in clean air cities, may be just as harmful.

In this latest study, researchers analyzed data from nearly 700 patients who had heart attacks between 2003 and 2010. The patients all lived within 10 km of Jena University Hospital in Jena, Germany, and were admitted to the hospital after having a heart attack.

Researchers also compared concentrations of air pollutants in the patients one, two, and three days before heart attack symptoms occurred to the concentrations in the previous week and the week after the heart attack.

The data indicated more than 20 mg/m3 increase in the level of nitric oxides in the blood within a 24 hour period was linked with a 121% increase of heart attack.

Nitrogen oxide is primarily a product of exhaust from traffic. However, other sources may contribute to it.

The increased risk of heart attack seen with the rapid increases of air pollution was similar to the risk seen with sustained long-term exposure to air pollution. Long-term exposure has also been linked to an increased risk of Alzheimer’s Disease, and accelerated aging in children.

The study did not look at why the air pollution rates spiked. However, study authors speculated the sudden increases may have been linked to increased traffic rates over holidays or meteorological conditions associated to smog.

Researchers said the findings are especially important, considering the effects and risk of heart attack was seen in Jena, Germany, a so-called “clean air” city, not a city known for high levels of air pollution. Jena has experienced only a few days of air pollution that exceeded European Union daily limits in the last few years.

This translates to an increased risk for more people. To that end, researchers are calling for long-term studies to confirm the findings.