Breathing in car fumes linked to heart attack

BREATHING in heavy traffic fumes can trigger a heart attack, UK experts say.

Prof. Jeremy Pearson, an associate medical director at the British Heart Foundation, which co-funded the study, said: “This large-scale study shows that your risk of having a heart attack goes up temporarily, for around six hours, after breathing in higher levels of vehicle exhaust.

“Pollution can have a major effect on your heart health, possibly because it can ‘thicken’ the blood to make it more likely to clot, putting you at higher risk of a heart attack.”

The researchers say in the British Medical Journal  that pollution probably hastens rather than directly cause attacks. But repeated exposure is still bad for health, they say, substantially shortening life expectancy.

The research looked at the medical records of almost 80,000 heart attack patients in England and Wales, cross-referencing these details with air pollution data.

This enabled the investigators to plot hourly levels of air pollution against onset of heart attack symptoms and see if there was any link.

Higher levels of air pollution did appear to be linked with onset of a heart attack lasting for six hours after exposure.

After this time frame, risk went back down again.

Krishnan Bhaskaran from the London School of Hygiene and Tropical Medicine, who led the research, said the findings suggested that pollution was not a major contributing factor to heart attacks.

For example, being exposed to a spell of medium-level rather than low-level pollution would raise heart attack risk by 5%, by his calculations.

“It looks like it brings heart attack forward by a few hours. These are cardiac events that probably would have happened anyway.”

Adapted from BBC