Study: Traffic jams might lead to heart attack

Traffic jams are linked with a much higher risk for people in the traffic to suffer a heart attack, a new study has found.

After a four-year analysis of nearly 1,500 heart attack cases, a team of German and American researchers came to the conclusion that making one's way through traffic -- whether as a driver, a rider of public transport, or even a bicyclist -- seems to more than triple the chances for experiencing a heart attack in the first hour immediately following exposure.

The researchers from Institute of Epidemiology in Helmholtz Zentrum Munchen, Germany, and Harvard's School of Public health presented their study to the American Heart Association's Cardiovascular Disease Epidemiology and Prevention annual conference, in Palm Harbor, Florida last week. A copy of the study was made available to Xinhua on Monday.

To explore the issue, the team focused on a pool of heart patients in the southern German town of Augsburg.

One-quarter of the patients were women, and the average age was60. All had suffered a heart attack between 1999 and 2003, and all were subsequently interviewed to recall experiences in the four days leading up to the event that might have triggered the first symptoms.

The researchers found that 8 percent of the heart attacks were specifically attributable to having been in traffic -- the kind which German researcher Annette Peters described as "local, everyday life commuting."

In addition to identifying a 3.2 times higher risk for suffering a heart attack within the first hour after traffic exposure, the research team found that even six hours after exposure, there remained a significant -- though small – increase in risk.

Being the driver of a car was the most common form of traffic exposure, followed by being a rider of public transportation and/or bicycling.

"We found that when people are participating in traffic, they have a threefold increased risk to experience a heart attack one hour later," said Peters, one of the study authors.

"For someone with a very low risk for a heart attack, this doesn't mean much," Peters noted. "But for someone already at a higher risk for a heart attack -- because of lifestyle issues such as smoking or being overweight, or perhaps because of genetic makeup -- then traffic might be an additional stressor that could cause a heart attack to occur at this time."

But the finding does not isolate which particular virtue of road congestion -- stress, pollution, car exhaust or noise -- might be the driving force behind the apparent cardiovascular threat.