Traffic Exposure May Trigger Heart Attacks

People who have had a heart attack are likely to report having been in traffic shortly before their symptoms began, researchers reported at the American Heart Association’s 49th Annual Conference on Cardiovascular Disease Epidemiology and Prevention.

In a German study of patients who had a heart attack, researchers found the patients to be more than three times as likely to have been in traffic within an hour of the onset of their heart attack. The researchers also observed small but statistically significant increases in the chance that a heart attack occurred within six hours after exposure to traffic.

Driving a car was the most common source of traffic exposure, but taking public transportation or riding a bicycle were other forms of exposure to traffic. Overall, time spent in any mode of transportation in traffic was associated with a 3.2 times higher risk than time spent away from this trigger. Females, elderly males, patients who were unemployed, and those with a history of angina were affected the most by traffic.

“Driving or riding in heavy traffic poses an additional risk of eliciting a heart attack in persons already at elevated risk,” said Annette Peters, Ph.D., lead author of the study and head of the research unit at the Institute of Epidemiology, Helmholtz Zentrum Muchen, Germany. “In this study, underlying vulnerable coronary artery disease increased the risk of having a heart attack after driving in traffic.”

via Traffic Exposure May Trigger Heart Attacks.

Also see: Traffic Triples Heart Attack Risk on WebMD.

The pollution is the problem, specifically, fine particulate matter which includes toxic metals, etc.

Adverse health effects have been associated with diesel particulate matter, according to the Centers for Disease Control. The causal mechanisms are unclear, but recent theories point at ultrafine particles because of their high lung-penetration efficiency and significant surface area—and to the presence of toxic metals on particles.

Diesel-powered vehicles are gaining in popularity as carmakers continue to make advances in clean diesel technology. Diesels are predicted to compete with hybrids as the preferred fuel efficient and clean car alternative. But just as American consumers begin to cast aside diesel’s dirty stigma, medical researchers from the United Kingdom and Sweden have found serious adverse health risks attributed to diesel exhaust.

In a study presented to the American Heart Association in early November, 2007, researchers reported that exhaust from diesel fuel increased clot formation and blood platelet activity in healthy volunteers—both of which are associated with higher risks of heart attack and stroke. The test group consisted of 20 men, age 21 to 44 years old, who were exposed to diesel exhaust levels comparable to what you would find at curbside on a busy street. After the exposure, researchers measured various blood levels and occurrences within each volunteer. These tests revealed increases in clot formation and platelet activation, significantly enough to be considered conclusive.

“Shortly after exposure to traffic air pollution, individuals are more likely to suffer a heart attack,” said Dr. Andrew Lucking, the lead author of study. “When a person is exposed to relatively high levels of diesel exhaust for a short time, the blood is more likely to clot.” It’s not clear whether these findings would apply to exhaust from conventional gasoline. Diesel engines generate many times more fine pollutant particles than comparable-sized gasoline engines. - hybridcars