Air pollution is a special risk for people who have experienced a heart attack, researchers warn today.
The study, by Dr Cathryn Tonne and colleagues at the London School of Hygiene & Tropical Medicine, UK, is the largest study ever on fine air-borne particulate matter (PM) and survival after acute coronary syndrome.
The researchers used hospital records of 154,204 surviving patients in England and Wales from 2004 to 2007. They also calculated average air pollution concentrations for 2004 to 2010. Patients were followed for about 3.7 years, during which time there were 39,863 deaths.
The highest exposures to PM2.5 – very tiny particles that measure 2.5 micrometres or less – and other air pollutants were in London, while the lowest were in the North East of England. These particles come mainly from road traffic and industry.
Death rates increased with greater exposure to PM2.5, say the researchers. "We found that for every ten micrograms per cubic metre increase in PM2.5 there was a 20% increase in the death rate," said Dr Tonne.
"For example, over one year of follow-up after patients had been admitted to hospital with acute coronary syndrome, there would be 20% more deaths among patients exposed to PM2.5 levels of 20 micrograms per cubic metre, compared to patients exposed to PM2.5 levels of 10 micrograms per cubic metre."
Details are published in the European Heart Journal today (20 February). "Responsibility for controlling air pollution rests on national governments," added Dr Tonne.
Maureen Talbot of the British Heart Foundation commented: "We’re currently funding further research in this area, to establish how air pollution affects the blood vessels and so increase our knowledge about its effects on the heart."
Tonne, C. and Wilkinson, P. Long-term exposure to air pollution is associated with survival following acute coronary syndrome. European Heart Journal 20 February 2013 doi:10.1093/eurheartj/ehs480
Leave a Reply