A Swedish research published in July 2006 on the journal Epidemiology showed that people who have spent decades living in heavily polluted areas have a greater risk of fatal heart attack, especially for those heart attacks that occur outside hospitals. The findings implied that sudden death might be of special importance in relation to long-term air pollution exposure. (Full News Report)

It was also discovered in the research that people who had ever lived in air pollution "hot spots" had a 23% increased risk of heart attack, and a 40% increased risk of fatal heart attack.

The researchers noted that pollution exposure increases heart attack risk by causing chronic inflammation, increasing the rate of hardening of the coronary arteries (which supply blood to the heart itself), and altering the heart function.