A new study discovers that breathing particulate matter air pollution may cause heart arrhythmia in healthy teenagers.
In new research published in the Journal of the American Heart Association, researchers find that the negative cardiovascular effects, such as heart arrhythmia of air pollution commonly seen in adults are also impacting teenagers.
Heart arrhythmias are experienced by over two million people in the UK. It is common in older people; however, this new research illuminates that this condition could become more prevalent in healthy teenagers. Symptoms include palpitations, feeling dizzy, fainting or being short of breath.
“While relatively rare, irregular heart rhythms can lead to sudden cardiac death in otherwise healthy adolescents and young adults. Our findings linking air pollution to irregular heart rhythms suggest that particulate matter may contribute to the risk of sudden cardiac death among youth,” said Fan He, PhD, lead author of the study and an instructor in public health sciences at the Penn State College of Medicine in Hershey, Pennsylvania. “Since childhood and adolescent cardiovascular conditions can track into adulthood and affect the risk of major cardiovascular disease later in life, identifying modifiable risk factors of cardiac arrhythmia that may cause sudden cardiac death among adolescents should be of great public interest.”
The impact of air pollution on heart health
The study examined the impact of breathing fine particulate on heart rhythms of adolescents. Fine particulates (PM2.5) are less than 2.5 microns in size and can easily be inhaled deep into the lungs and even enter the bloodstream. Particles smaller than 2.5 microns usually come from fuel combustion, such as car exhausts. Once this is inhaled, it can irritate the lungs and blood vessels around the heart. Previous research has illuminated that these pollutants can increase the process of disease in the arteries over time.
The researchers analysed how air pollution impacts heart arrhythmias characterised by premature contraction in the heart muscle. In premature atrial contractions (PAC), the heartbeat originates from the atria (top chambers of the heart). This typically causes no symptoms, but frequent contractions can increase the risk of atrial fibrillation – a severe form of heart arrhythmia. Due to the lack of symptoms, this leads to affected individuals not receiving treatment.
Analysing potential heart arrhythmias in 322 teenagers
The health data of 322 adolescents (average age 17 years; 56% males; 79% non-Hispanic white teenagers) living in central Pennsylvania were involved in the Penn State Child Cohort study. The original study dates back to 2002 and 2006 when these children were aged six to 12 years. The researchers reviewed the results from the follow-up evaluation almost 7.5 years later, and at this point, the children were free of cardiovascular conditions and considered low risk for heart arrhythmias.
However, in the more recent follow-up, the researchers measured exposure to fine particulate matter in the air using a nephelometer for 24 hours and EKG tracings of each teen’s heart rhythms via a wearable device.
They found that the average PM2.5 concentration in the participants was 17 micrograms of particulate matter per cubic meter of air (µg/m3) per day, which is much below the health-based air quality of 35 µg/m3 established by the U.S. Environmental Protection Agency (EPA).
The study found:
- 79% of the participants had at least one heart arrhythmia during the 24-hour study period. Within that group, 40% had premature atrial contractions, 12% had only premature ventricular contractions, and 48% had both.
- A 5% increase in the number of premature ventricular contractions within two hours of exposure was noted for each increase of 10 µg/m3 in PM2.5.
- No association was found between the concentration of particulate matter and the number of premature atrial contractions.
“It is alarming that we were able to observe such a significant impact of air pollution on cardiac arrhythmias when the air quality remained well within the health-based standards established by the EPA. It may suggest that adolescents who live in highly polluted areas such as inner cities are at even higher risk,” Fan He said.
Furthermore, the results were consistent with data previously obtained in adults using similar methods from these researchers and others, although the increase in premature ventricular contractions was even higher in adults. Reducing the risk of heart arrhythmia in adolescents may reduce their risk of developing heart disease as adults, according to the study authors.
“Our study found that air pollution increases the risk of cardiovascular diseases and sudden cardiac death, even among healthy adolescents,” Fan He said. “Protective measures, such as wearing masks and avoiding vigorous physical activities, may be warranted on days that particulate matter concentration is high, especially during early morning rush hours.”
