Stroke risk from traffic noise

Wednesday January 26th, 2011

Elderly people who live near noisy roads may face an increased risk of stroke, researchers warn today.

Previous studies have indicated that long-term exposure to road traffic noise increases the risk of heart disorders, so researchers from Denmark looked at the effect on stroke risk.

Using figures on 51,485 participants, they compared exposure to road traffic noise for the 1,881 people who suffered a stroke between 1993 and 2006, against those who did not suffer a stroke. The analysis took into account air pollution and several lifestyle factors such as smoking, diet, alcohol and caffeine intake.

Overall, they found a 14 per cent raised risk of stroke for every ten decibels rise in road traffic noise. On further investigation, this risk was only significant for people over 64 years of age, who had a 27 per cent increase for every ten decibels.

They also found signs of a "threshold limit" of about 60 decibels, above which the risk increased even faster. About a third of participants were exposed to this level of noise.

Lead researcher, Dr Mette Sorensen of the Danish Cancer Society in Copenhagen, Denmark, said: "If we assume that our findings represent the true risk, and the association between traffic noise and stroke is causal, then an estimated eight percent of all stroke cases, and 19 per cent of cases in those aged over 65, could be attributed to road traffic noise."

She estimates that about 600 new cases of stroke could be attributed to road traffic noise in Denmark each year.

This highlights the need for action to reduce people's exposure to noise, she says, but added: "More research is needed before any firm conclusions can be made."

Sorensen, M. et al. Road traffic noise and stroke: a prospective cohort study. The European Heart Journal, published online January 26, 2011.

Tags: Europe | Geriatric Health | Heart Health

Printer friendly page