Exposure to high levels of aircraft noise is associated with an increased risk of cardiovascular disease, find two studies published on bmj.com today.

 

Previous studies of exposure to aircraft noise have examined the risk of hypertension, but few have examined the risk of cardiovascular disease and results are inconsistent. So researchers based in London set out to investigate the risks of stroke and heart disease in relation to aircraft noise among 3.6 million residents living near London Heathrow, one of the busiest airports in the world.

 

They compared hospital admissions and mortality rates for stroke, coronary heart disease, and cardiovascular disease from 2001-05 in 12 London Boroughs and nine districts west of London. Levels of aircraft noise for each area were obtained from the Civil Aviation Authority (CAA).

The researchers found increased risks of stroke, coronary heart disease, and cardiovascular disease for both hospital admissions and mortality, especially among the 2% of the study population exposed to the highest levels of daytime and night time aircraft noise.

 

Factors that could have affected the results, such as age, sex, ethnicity, social deprivation, smoking, air pollution, and road traffic noise were also taken into account. Accounting for the prevalence of people of South Asian ethnicity reduced the observed risks for hospital admissions for coronary heart disease and cardiovascular disease.

 

However, the authors were unable to distinguish between night time and daytime noise and say more research is needed to determine if night time noise that disrupts sleep may be a mechanism underlying these associations.

 

They stress that further studies are needed to test whether aircraft noise causes these increases in risk or if these results can be explained by some other unmeasured (confounding) factors.