(NaturalNews) Living in areas with high traffic noise may lead to higher blood pressure and a concurrently higher risk of heart attack or stroke, according to a study conducted by researchers from Lund University Hospital in Sweden and published in the journal Environmental Health.
"Road traffic is the most important source of community noise," said lead author Theo Bodin. "We found that exposure above 60 decibels was associated with high blood pressure among the relatively young and middle-aged, an important risk factor for cardiovascular diseases such as heart attack and stroke."
Previous studies have found connections between living near airports and higher blood pressure. Scientists believe that constant noise may place the body in a state of chronic stress, leading to higher heart rate and blood pressure. It may also harm health by disturbing sleep patterns.
Researchers examined health and residence data on more than 24,000 adult residents of Sweden, using their home addresses to determine the average level of ambient traffic noise in their neighborhoods. Young and middle-aged adults being regularly exposed to average noise levels between 45 and 65 decibels were significantly more likely to have high blood pressure than those in quieter neighborhoods, with risk increasing proportionally to noise level.
Among the middle-aged, 28 percent of those living in areas with noise averaging above 64 decibels reported high blood pressure. Only 17 percent of adults in the same age group and quieter neighborhoods suffered from hypertension. The numbers in younger adults were similar.
The researchers did not know why there appeared to be no link between noise and blood pressure in the elderly.
"The effect of noise may become less important, or harder to detect, relative to other risk factors with increasing age," Bodin said. "Alternatively, it could be that noise annoyance varies with age."
Sixty-five decibels is a little louder than a normal conversation. Recent data suggest that 30 percent of the European Union's population is exposed to average traffic noise of 55 decibels or higher continually.