Scientists at Imperial College London and other European institutions monitored 140 sleeping volunteers in their homes near London's Heathrow and three other major European airports. The researchers found volunteers' blood pressure increased noticeably after they experienced a noise louder than 35 decibels, such as an airplane flying overhead, traffic passing outside or a partner snoring, Imperial College said Wednesday in a news release.

Noise from aircraft caused an average increase in systolic blood pressure of 6.2 mmHg and an average increase in diastolic blood pressure of 7.4 mmHg. The report said the decibel level was the key factor in determining the effect each noise event had on the volunteers' blood pressure.

The findings were published in the European Heart Journal.