Living near loud traffic increases your risk of having a heart attack
Researchers say the link could be due to noise causing stress and sleep disturbances
10:15 GMT, 22 June 2012
Loud traffic noise increases the risk of heart attack, a study shows.
Researchers say that each ten per cent rise in volume comes with a 12 per cent higher risk of heart attack.
Previous studies had investigated the combined effects of noise and pollution, although the results were inconclusive.
But the latest study of more than 50,000 people has found a ‘clear relationship’ between noise and heart attacks, reports journal PLoS ONE.
Each ten per cent rise in traffic volume comes with a 12 per cent higher risk of heart attack
Dr Mette Sorenson, of the Danish Cancer Society, said that the reason for the relationship is unknown, but may be due to increased stress and sleep disturbances associated with high traffic noise.
He said: 'In this study residential exposure to road traffic noise was associated with a 12 per cent higher risk of myocardial infarction (MI) per ten decibel exposure to noise, showing a clear dose response relationship.'
Suggesting one possible explanation he said: 'Sleep disturbances can contribute to cardiovascular risk, leading to the hypothesis that exposure to noise during the night might be more harmful than daytime exposure.
'The sleep structure generally becomes more fragmented with age and elderly people are thus more susceptible to sleep disturbances.'
He said it was possible that changes in lifestyle caused by disrupted sleep could play a part.
But he adds: 'Stress and sleep disturbances can cause changes to lifestyle habits, including increased tobacco smoking and thus potentially a stronger association between traffic noise and MI among smokers.
'However we found indications of a high effect of road traffic noise on MI among never smokers.'
He points out that those studied mainly lived in urban areas, meaning other factors could be at play.
But he said: 'The present study shows a positive association between residential exposure to road traffic noise and risk for MI.'