LONDON, UK — Aircraft noise from some of the world's busiest airports is linked to an increased risk of hospital admissions for cardiovascular disease, according to two new papers. The studies broaden concerns about the impact of living close to airports; previously, aircraft noise, as well as other "sound pollutants," has been linked to hypertension.
In the first of two studies published online October 8, 2013 in BMJ, Dr Anna L Hansell (Imperial College London, UK) and colleagues assessed hospital admissions for 3.6 million people living near Heathrow Airport. Their paper linked daytime and nighttime aircraft noise and hospital visits for stroke, coronary heart disease, and cardiovascular disease by comparing residents in the noisiest areas with those living farther from the airport.
They found that, after adjustment for confounders, high-noise areas (>63 dB) had significantly increased risks for all three diagnostic codes as compared with the quieter areas (<51 dB).
High vs Low Aircraft Noise Exposure
|Admission diagnosis||Relative risk||95% CI|
|Coronary artery disease||1.21||1.12–1.31|
In the second paper, Dr Andrew W Correia (NMR Group, Somerville, MA) and colleagues looked at hospitalization for cardiovascular disease among subjects 65 years or older according to "contours of aircraft noise levels" around 89 airports in the US.
They report that every 10-dB increase in noise exposure (by zip code) was associated with a 3.5% higher rate of hospital admissions for cardiovascular disease. The observation held up after they controlled for other covariates, including air pollution as well as ethnic and socioeconomic factors. Importantly, note the authors, the effects were particularly marked at the highest levels of aircraft noise (above the 90th percentile for noise exposure) suggesting a threshold effect above 55 dB.
In an accompanying editorial, Dr Stephen Stansfeld (Barts and the London School of Medicine, UK) asserts: "the link seems real."
The findings also echo a somewhat larger body of work looking at traffic noise, including the large HYENA study. He notes that a link between aircraft noise and stroke, seen in the Hansell et al paper, "is new and fits with associations between aircraft noise and hypertension and between road traffic noise and death from stroke."
Other factors that could not be controlled for in the current analyses include individual-level confounders, including smoking status and household income, he notes. "There is a need for prospective cohort studies of exposure to aircraft and road traffic noise . . . that might also take account of air pollution, social disadvantage, and migration in and out of study areas," Stansfeld writes.
Still, he continues, the results have implications for the siting of airports, he concludes. "Planners need to take this into account when expanding airports in heavily populated areas or planning new airports."
Hansell disclosed receiving consultancy fees from AECOM as part of a UK Department for Environment, Food and Rural Affairs report on health effects of environmental noise. Disclosures for the coauthors are listed in the paper. Stansfeld disclosed being a member of the Acoustic Review Group for High Speed 2. Correia et al had no conflicts of interest.
Heartwire from Medscape © 2013 Medscape, LLC
Cite this: Aircraft Noise and CVD: Two New Studies Bolster Link - Medscape - Oct 09, 2013.