Blood type may indicate heart attack risk from pollution

People with blood types A, B and AB are at bigger risk of heart attacks from air pollution

People with blood types A, B and AB are at bigger risk of heart attacks from air pollution

A study presented in April analysed more than 1.3 million people and also found that people with non-O blood types stood a higher risk of cardiovascular events including heart attacks and stroke, although it did not establish what causal mechanisms were behind the pattern. This new study was created to build on and tie together those findings and test the influence of one variation: the impact of an individual's blood type.

That said, everybody's level of risk appears to rise when PM2.5 concentration rises above the threshold of 25 micrograms of fine particles per cubic metre of air - it's just that the risk goes up more for people with non-O blood types.

'The primary mutation we studied differentiates between O blood types and non-O, which includes positive and negative A, B, and AB blood types.

People with one blood type are at higher risk of air-pollution-related heart attacks if they already suffer with coronary heart disease, according to a new study.

Although the team cautions that a heart attack is never a certainty even with these factors and pre-existing coronary disease.

He said at the 65 micrograms per cubic metre pollution level, a person with type O blood faces a risk that is 40 per cent higher than if the air wasn't polluted.

Benjamin Horne, lead investigator, said: "The association between heart attacks and pollution in patients with non-O blood isn't something to panic over, but it is something to be aware of".

Dr Horne said: 'You have to have other characteristics for coronary disease to progress to a heart attack.

Dozens of genes have been shown in large worldwide studies to predict the onset of coronary artery disease in people who are free of the disease.

The results were presented at the 2017 American Heart Association Scientific Sessions in California.

The study had looked at clinical data for Intermountain Healthcare patients who were treated between 1993 and 2007. The analysis of air quality was done at BYU.

During a winter inversion, the PM2.5 pollution level can occasionally reach as high as 100 micrograms per cubic meter, but 50-60 is more typical.

People who have A, B, and AB blood types carry the ABO gene and the team at the Intermountain Medical Centre Heart Institute in Utah, wanted to find out whether a variant of this gene was linked to elevated risk of heart attacks during periods of high air pollution.

The World Health Organisation says exposure to PM2.5 pollution should not exceed 10 micrograms per cubic metre of air for it to be considered safe to breathe. "Exercise indoors. And make sure they're compliant with taking their heart medication to reduce their risk".

Dr Horne added: 'In the information we provide to our patients about pollution, we try to stress that they can do something about it to reduce their risks: stay indoors out of pollution.