Air pollution may lead to irregular heartbeats in healthy teens

Respiratory particulates (that is, fine particles suspended in the air) Air pollution may lead to arrhythmias (arrhythmias) in healthy teens, according to new research published today in Journal of the American Heart Associationan open access, peer-reviewed journal of the American Heart Association.

While the negative cardiovascular effects of air pollution on adults have already been demonstrated, this study is the first to assess the impact of air pollution on adolescents in the general population.

While arrhythmia is relatively rare, it can lead to sudden cardiac death in otherwise healthy adolescents and young adults. Our findings linking air pollution to cardiac arrhythmias suggest that fine particulate matter may contribute to the risk of sudden cardiac death in young adults. Because cardiovascular disease in childhood and adolescence can pass into adulthood and influence the risk of major cardiovascular disease later in life, identifying modifiable risk factors for arrhythmias that may cause sudden cardiac death among adolescents It should be of great public interest.”

Van Hee, Ph.D., study lead author and instructor in public health sciences at Penn State College of Medicine in Hershey, Pennsylvania

The study examined the effect of breathing fine particles on heart rhythms in adolescents. Fine particulate matter (PM2.5) with a size of less than 2.5 microns and can be easily inhaled deep into the lungs and even enter the bloodstream. Particles smaller than 2.5 microns are usually associated with fuel combustion, such as particles from automobile exhaust or wildfires. Once inhaled, pollutants irritate the lungs and blood vessels around the heart, and previous research has suggested that over time, pollutants increase the disease process in the arteries.

The researchers analyzed the effect of particulate pollution in breathing on two types of irregular heartbeat characterized by premature contraction of the heart muscle, often described as “skip heartbeat”. In premature atrial contractions (PACs), the heartbeat originates from the atria (upper chambers of the heart). This usually causes no symptoms or harm, however, and frequent early atrial contractions have been associated with an increased risk of atrial fibrillation – a severe form of arrhythmia in which the upper chambers quiver rather than beat effectively, increasing the risk of blood clots and brain attack. Premature ventricular contractions (PVCs) occur when the heartbeat originates from one of the ventricles (the lower chambers of the heart). They also increase the risk of heart attack, stroke, heart failure, or sudden cardiac death.

If early contractions do not cause any symptoms, they are not treated. However, if they occur often and lead to a feeling of skipped heartbeat, rapid heartbeat, or heart palpitations, treatment with medications, implantable devices, or procedures may be recommended.

Researchers analyzed the health data of 322 adolescents (median age 17 years; 56% male; 79% non-Hispanic white adolescents) living in central Pennsylvania who participated in a follow-up assessment in the Pennsylvania Children’s Cohort Study. This study, conducted between 2002 and 2006, initially recruited children aged 6 to 12 years. The data analyzed in this study reviewed the results of follow-up evaluation after approximately 7.5 years (2010-2013). This group of children was free of major cardiovascular disease and considered to be at low risk for arrhythmias. In the follow-up study, researchers simultaneously measured exposure to fine particles in the air each teen breathed (using a device called a nucleimeter) for 24 hours and an ECG tracked each teen’s heart rhythms via a small wearable device called a Holter monitor. .

average PM2.5 The concentration measured in the study was about 17 micrograms of particles per cubic meter of air (µg/m.3) per day, which is well below the healthy air quality standard of 35 mcg/m3 Established by the US Environmental Protection Agency (EPA).

The study found:

  • 79% of the participants had at least one irregular heart rhythm during the 24-hour study period. Of this group, 40% had only early atrial contractions, 12% had only early ventricular contractions, and 48% had both.
  • A 5% increase in the number of premature ventricular contractions was observed within 2 hours of exposure for each increment of 10 mcg/m.3 in PM2.5.
  • No association was found between particle concentration and the number of premature atrial contractions.

“It is alarming that we were able to observe such a significant effect of air pollution on arrhythmias when air quality remained within the health standards set by the Environmental Protection Agency. This may indicate that adolescents living in highly polluted areas such as inner cities are even vulnerable at greater risk.”

The results were consistent with data previously obtained in adults using similar methods from these and other researchers, although the increase in premature ventricular contractions was higher in adults. According to the study authors, reducing the risk of arrhythmias in adolescents may reduce the risk of heart disease in adults.

“Our study found that air pollution increases the risk of cardiovascular disease and sudden cardiac death, even among healthy adolescents,” he said. “Preventive measures, such as wearing masks and avoiding vigorous physical activities, may be warranted on days when particle concentration is high, particularly during peak hours in the early morning.”

Robert DeBrock, American Heart Association volunteer expert, Robert D. Brooke has co-authored several American Heart Association scientific statements on air pollution.

“evening2.5 “Levels have fallen dramatically since the 1970s and 1980s due to regulations that have undoubtedly been associated with improved health effects and life expectancy,” Brooke said. We are outlined in a recent AHA scientific statement, titled Personal Protection Measures Against Particulate Air Pollution. Exposure, strategies, and activity or behavioral changes that may reduce exposure to pollution, such as portable air cleaners, face masks, respirators, and off-peak exercise. However, there have been no studies to demonstrate that these procedures can actually prevent adverse clinical health effects such as heart attacks.”

According to the American Heart Association’s 2020 policy statement citing a global study, ambient air pollution is widely recognized as an important contributor to cardiovascular disease and death. In 2017, exposure to particulate matter air pollution was estimated to be associated with more than 7 million premature deaths and the loss of 147 million years of healthy life globally. The association recommends further development of evidence-based policy approaches, continued investment in research and more innovation and transformative partnerships to reduce the cardiovascular burden of ambient air pollutants in the United States.

“The most interesting and important aspect of this study is that the results were clearly found in healthy young adolescents,” Brooke said. The study adds support to the concern that even healthy young adults are not immune to adverse cardiovascular responses to PM.2.5 and at exposure levels within the national 24-hour ambient air quality standards set by the Environmental Protection Agency. It is plausible that the findings help explain the possible cause of the time to onset of arrhythmias and even sudden death in some susceptible young adults.”

Dr. He and colleagues are currently evaluating the effect of air pollution on other indicators of the heart’s electrical activity.

This study was limited in its inability to analyze the effect of air pollution on different subtypes of premature ventricular contractions, which may help cardiologists better understand how pollution affects heart function. The results of this study on adolescents may not be generalizable to younger children.


Journal reference:

He, F. et al. (2022) Acute effect of fine particulate air pollution on cardiac arrhythmias in a population sample of adolescents: The Pennsylvania Children’s Cohort. Journal of the American Heart Association.