New research examines the effect of living next to an airport - specifically, of being exposed to the noise of aircrafts flying by - on the risk of developing high blood pressure, medically diagnosed heart flutter, and stroke.
Nobody likes the sound of cars honking or engines revving. Long-term exposure to road traffic noise has been linked to poor sleep, poor cognitive performance, and even cardiovascular disease.
But does being exposed to air traffic noise have the same effect? A new study, published in the journal Occupational & Environmental Medicine, investigates the link between aircraft noise exposure and cardiovascular health.
The first author of the study is Konstantina Dimakopoulou, of the Department of Hygiene, Epidemiology, and Medical Statistics at the National and Kapodistrian University of Athens in Greece.
The study examined 420 people who lived near the Athens International Airport in Greece and who were also enrolled in the HYENA study.
The HYENA study is an international, cross-sectional study that aimed to evaluate the health effects of aircraft noise between 2004 and 2006.
Dimakopoulou and her colleagues linked the residential addresses of the participants with noise levels starting from under 50 decibels to over 60 decibels. They defined "daytime aircraft noise" as occurring between 7 a.m. and 11 p.m., and "nighttime aircraft noise" as that between 11 p.m. and 7 a.m. the following day.
In terms of the statistical tools used, the team applied multiple regression models as well as Cox proportional hazard models to adjust for factors that may influence the results.
Overall, almost half of the participants (49 percent) were exposed to more than 55 decibels of aircraft noise during the day, and approximately 1 in 4 (a little over 27 percent) were exposed to more than 45 decibels during nighttime. Only 11 percent of the participants were exposed to levels of above 55 decibels of noise coming from the road traffic.
As for the incidence of adverse cardiovascular events, 71 people received a high blood pressure diagnosis over the 2-year study period, 44 participants were newly diagnosed with cardiac arrhythmia, and 18 participants had a heart attack.
According to the researchers, hypertension and cardiac arrhythmia correlated significantly with higher levels of aircraft noise exposure, particularly at night.
Regarding hypertension, nighttime aircraft noise correlated not only with new cases of high blood pressure, but with all cases.
Specifically, for every additional 10 decibels of aircraft noise, the risk of being newly diagnosed with hypertension increased by over 50 percent. When all of the high blood pressure cases were included, the risk rose to 69 percent.
Nighttime aircraft noise also correlated with a doubled risk of diagnosed heart flutter, or arrhythmia, but the correlation was valid for all arrhythmia cases, not just for newly diagnosed ones. The correlations with stroke, on the other hand, were not statistically significant.
By contrast, the associations with road traffic noise were "weaker and less consistent."
This being an observational study, it cannot draw any conclusions about cause and effect. Further limitations of the study include the small population sample and the lack of access to information about the causes of death for those who died during the study period.
However, the authors seem confident in their results:
"The findings [...] suggest that long-term exposure to aircraft noise, particularly during the night, is associated with incident hypertension and possibly, also, cardiovascular effects.
They conclude that, "We anticipate that the research undertaken will be useful for improving the quality of public health in areas where exposure to transportation-related noise is prevalent."