People with A, B, or AB blood type have a greater chance of suffering a heart attack when air pollution levels are significantly high compared to those with type O, researchers say. 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.
People with certain blood types are at increased risk for a heart attack from high levels of air pollution, a new study finds.
Those with A, B and AB blood types have an "elevated risk" of having a coronary compared to people with the O blood type, the most common in the United Kingdom and present in 48 per cent of the population, USA scientists say.
'The one that's been found in genetic studies to be lower risk is O. The other three were higher risk'.
"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", he added.
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.
Safe levels of air pollution are generally considered to be under 20 micrograms per cubic meter, but during levels of high pollution, the PM2.5 count - the measure of small particulates in the air - raise to around 60 micrograms per cubic meter.
Although the team cautions that a heart attack is never a certainty even with these factors and pre-existing coronary disease.
"You have to have other characteristics for coronary disease to progress to a heart attack", Dr. Horne said.
"Two years ago we published findings that showed once you go above that, each additional 10 micrograms of pollution per cubic metre of air provided substantially higher risks", says Horne.
The study had looked at clinical data for Intermountain Healthcare patients who were treated between 1993 and 2007.
The team had previously found that there was a link between small particulate PM2.5 pollution and heart attack, admission to the hospital with unstable chest pain, heart failure and atrial fibrillation.
He said at the 65 micrograms per cubic metre pollution level, a person with type O blood faces risk that's 40 per cent higher than if the air wasn't polluted.
But they wanted to conduct the new research, which was unveiled this week at the 2017 American Heart Association Scientific Sessions, to test how impactful an individual's blood type can be on their risk.
Dr Horne warns that people in A, B, or AB blood groups should consider staying indoors to minimise their risk if they already have underlying heart conditions, such as coronary artery disease.
"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", Horne says.