Night-time noise increases the blood pressure in the long term

New study on aircraft noise: Night-time noise causes blood pressure to rise

07/03/2013

Aircraft noise causes health problems such as high blood pressure and can even trigger a heart attack or stroke. A study of the Mainz University Hospital has shown that the noise affects the vascular function.

Political consequences demanded
Aircraft noise increases the release of the stress hormone epinephrine and impairs vascular function. This has resulted in a study with 75 participants, as the Mainz University Hospital announced on Tuesday. Study Director Thomas Münzel said: „We know that aircraft noise can cause high blood pressure, heart attacks and even strokes.“ So far, however, the exact mechanisms leading to these cardiovascular diseases have not been known. According to Münzel, director of the II. Medical Clinic and Polyclinic new insights were gained: „This study shows very clearly how and at what sound levels vascular damage occurs.“ The results of the study should lead to political consequences, the scientists demanded.

Aircraft noise in the bedroom
For the study, 75 healthy men and women were sonicated with aircraft noise averaging 60 decibels at night in their bedrooms. The subjects were divided into three groups. Some were sounded with 30 simulated night flights per night, the others with 60 and for the third group the night remained noise-free. 30 flights corresponded to an equivalent continuous noise level of 43 decibels, 60 flights that of 46 decibels. Such values ​​are regularly reached in Rhein-Main.

Disorders like smokers
The participants were filmed during the study with an infrared camera while sleeping and with ultrasound devices, the researchers determined the vascular function. It was found that night-time noise in the subjects increased the stress hormone epinephrine and significantly worsened the function of the blood vessels. First author Frank Schmidt from the University Medical Center Mainz explained: „Our study results show that in the same way as the noise of the air increases, the ability of the arteries to expand increases.“ According to Schmidt, several of the subjects developed a dysfunction of the inner wall of the blood vessel, as can be observed, for example, in smokers.

Man does not get used to the noise
Münzel summarized the main finding of the investigation: „Aircraft noise leads to a worsening of vascular function even in healthy subjects in just one night.“ A surprising result was also that showed: the man obviously does not get used to the nocturnal aircraft noise. For example, the researchers allowed one night with 30 overflights to follow one night with 60 overflights and found that an increase in the number of flights led to a significantly worse vascular function than in subjects who had to endure directly 60 overflights. „This means that you are not accustomed to the aircraft noise in the context of multiple sound systems, but the extent of vascular damage tends to increase“, so Münzel.

Vitamin C helps
In addition, the study showed that vascular damage can be treated with vitamin C. The vitamin binds the free radicals in the blood, which had formed due to the noise. „Of course, this does not mean that the effects of aircraft noise can be easily solved by vitamin C.“, so Schmidt.

Further studies
In many cities, aircraft noise has increased significantly in recent years. There is more need for scientific evidence on the health effects of increasing air traffic. Only in March, a study by the Federal Environmental Agency around Cologne / Bonn Airport revealed that aircraft noise increases the risk of cardiovascular disease. The Mainz University Medical Center is currently working on a study investigating the effects of aircraft noise in patients with existing cardiovascular diseases. And the noise impact study „NORAH“ (Noise-Related Annoyance, Cognition, and Health) is expected to deliver initial results by summer 2014 on the effects of traffic noise in general. (Ad)