丹麥一項研究發現，對65歲以上的人來說，街上聲音每增長10分貝，中風的風險就會增加27%。

Living in the city, you can't escape traffic noise. But it's not just a nuisance. If you're over 65, the noise might be a risk to your health, too—by increasing your risk of a stroke. That's according to a study in the European Heart Journal. [Mette Sørensen et al., "Road traffic noise and stroke: a prospective cohort study"]

The researchers studied over 51,000 Danish city dwellers for about a decade. And they mapped out noise levels at each person's home over time, using a noise calculating program. After accounting for other variables, like smoking history, diet and air pollution, they found that for the over-65 set, the risk of stroke rose 27 percent higher for every 10 decibels of noise exposure. The baseline was the volume of a normal conversation.

This study doesn't prove that road noise causes strokes. But previous studies have linked noise to heart attacks and higher blood pressure, too—possibly due to increased stress and sleep disturbance. For older people who already have trouble sleeping, the researchers say that extra tossing and turning could be the cause. So don’t just worry about the fumes if you're relocating to a busy city street—keep in mind your sound health, too.

—Christopher Intagliata