Aircraft Noise Poses Threats to Heart Health
Exposure to high levels of aircraft noise, especially at night, is associated with adverse cardiac remodeling in the form of concentric left ventricular (LV) hypertrophy and reduced LV systolic function, leading to an increased risk of major adverse cardiovascular events, according to a new study published in JACC.
Researchers analyzed cardiovascular MRI data from 3,635 UK Biobank participants with no self-reported hearing difficulties living near four major airports in the UK. Nighttime aircraft noise levels (Lnight) and weighted 24-hour day-evening-night aircraft noise levels (Lden) were provided by the UK Civil Aviation Authority and used with generalized linear models to investigate associations between noise exposure and cardiovascular MRI metrics. MRIs were performed at least three years after the estimates of aircraft noise in the participants' neighborhoods.
Of the more than 3,000 participants in the primary cohort, 3% experienced higher aircraft noise at night and 8% were exposed to higher noise levels throughout the day. Study results found that participants exposed to higher Lnight had 7% greater LV mass (95% CI, 4%-10%) and 4% thicker LV walls (95% CI, 2%- 5%) with a normal septal-to-lateral wall thickness ratio. In addition, those exposed to higher Lnight had worse LV myocardial dynamics.
"Our study is observational so we cannot say with certainty that high levels of aircraft noise caused these differences in heart structure and function," said senior author Gabriella Captur, MD. "However, our findings add to a growing body of evidence that aircraft noise can adversely affect heart health and our health more generally. Concerted efforts from government and industry are needed to reduce our exposure to aircraft noise and mitigate its impact on the health of millions of people who live close to airports or under flight paths."
According to Captur and colleagues, the study's findings were clearest for Lnight but were broadly similar in analyses using Lden. Additionally, BMI and hypertension appeared to mediate 10% to 50% of the observed associations. "Other factors that could be triggered by the stress response to aircraft noise include impaired sleep, inflammation, and atherosclerosis," said author Cristian Topriceanu, MD.
In a separate sub-cohort of 21,360 people from the UK Biobank, researchers concluded that the types of heart abnormalities observed in the study could result in two-to four-fold increased risks of a major cardiac event such as a heart attack, life-threatening heart rhythms, or stroke compared with individuals who living outside of high noise areas.
Commenting on the study, Thomas Münzel, MD; Marin Kuntic, PhD, et al., write that, "high decibels mean higher stakes, a simple formula for the cardiovascular fallout from aircraft noise." According to Münzel and colleagues, the findings "emphasize the need for immediate implementation of noise reduction policies to protect us and, in particular, vulnerable populations from the harmful effects of chronic aircraft noise exposure."
Clinical Topics: Cardiovascular Care Team, Prevention, Hypertension
Keywords: Stroke, Myocardial Infarction, Hypertension, Noise, Transportation