By Margarita Nahapetyan
A new German study has uncovered evidence that there is a strong link between traffic jams and developing a heart attack. It has been found that individuals were three times more likely to develop a condition if they had recently got stuck in traffic, most probably because of the exposure to the car fumes and other pollution they inhaled.
To come up with this conclusion, the researchers, led by Annette Peters, PhD, from the Institute of Epidemiology, Helmholtz Center in Munich, analyzed data of heart attack cases through the KORA registry in Augsburg, Southern Germany, between February 1999 and December 2003. They conducted interviews with nearly 1,500 patients in order to gather information and figure out what could be potential triggers of heart attack, including exposure to traffic four days before the heart attack symptom onset. All the patients had survived 24 hours after the heart attack.
The participants were asked standardized set of questions, such as what they were doing the day of the heart attack, where exactly they went, what means of transportation they used and how much time did they spend in a traffic jam. Twenty five per cent of the participants were women, and the average age, in general, was 60 years.
The experts found that driving a car turned out to be the most common source of traffic exposure, however, using public transportation or riding a bicycle were also other forms of traffic exposure. The researchers reported that 8 per cent of all heart attack cases were specifically attributable to having been in traffic -- the kind which Annette Peters described as "local, everyday life commuting." Overall, time spent in any type of transportation in traffic was associated with more than 3 times higher risk for experiencing a heart attack within the first hour immediately following the exposure.
In addition to this, the team has found that even six hours after the exposure, there still remained a significant, though small, increase in risk. Women, elderly men, patients who were unemployed, and those with a history of angina appeared to be particularly sensitive and were affected the most by traffic. Female partisipants, in fact, were more likely to have a 5 times greater risk for a heart attack following such exposure, compared to men. The researchers are not sure whether this is caused by physiological differences between the two genders, or simply a reflection of the smaller number of women - 325 in five years - that have been interviewed in the study.
The researchers are continuing with their investigation and plan to explain in future what it is about traffic and why exactly the exposure to it is being associated with a higher risk of heart attack. Presently, they are working on a study that involves more than 100 healthy volunteers, as part of the University of Rochester Particle Center, funded by the U.S. Environmental Protection Agency (EPA).
In this experiment, the participants are wearing heart monitors which provide electrocardiograms, that measure their exposure to air pollution and to noise. After each person is being outfitted, they drive to work or home or run errands and then return few hours later. For this study, the experts are also involving those with diabetes or impaired glucose tolerance. The data and findings from this trial are not yet available.
The findings of the new German research have been reported at the American Heart Association's 49th Annual Conference on Cardiovascular Disease Epidemiology and Prevention.