Three doctors give their views on aspirin
Dr Will Fennell: President of the Irish Heart Foundation, says aspirin has been widely used in the treatment and prevention of cardiovascular disease to good effect: "It is not only used to treat and prevent heart attacks but also thrombosis and clot extension. It is also complementary in the treatment of hypertension and in reducing the incidence of stroke."
Dr Fennell believes that aspirin should be given, albeit with caution, to people in the high-risk category, namely those who have not had a heart attack but are at risk, due to age, high blood pressure and/or cholesterol, diabetes, smoking etc.
He acknowledges there may be some side effects: "It should not be used across the board as a preventative as it's quite potent," he warns. "The major side effect is intestinal bleeding. There is a small incidence of allergic reaction."
Dr Fennell acknowledges the view of some health professionals and researchers that aspirin may be linked to Reyes Syndrome (a life-threatening brain and liver illness in children).
"As a result, it's felt that aspirin should not be given to children, especially if they have a fever," he says. "Junior aspirin is not available anymore. One of the problems of the past was that it presented a risk of overdose, contributed to by the sweet taste," says Dr Fennell.
It would appear, however, the many beneficial uses outweigh the possible side effects in adults.
Dr Fennell points to its uses when combined with other medicines in the treatment of cardiovascular disease.
"Aspirin, when combined with an expensive new drug called Clopidogrel, is of major benefit to coronary patients. It's considered essential for people with stents in place [a stent holds open a blocked blood vessel]."
"Clopidogrel has been shown to add further value to the benefits of aspirin. The combination is essential in stent patients, as it further enhances anti-platelet affects. When patients have stents in place and their anti-platelet medicines are stopped, they are at a higher risk of clots developing."
Dr Martin Daly: Chairman of the General Practitioners Committee, Irish Medical Organisation (IMO), says there is good evidence to show that aspirin is effective in secondary prevention of stroke and heart attack, but cautions against its use in primary prevention, saying its role is far less clear.
"Certainly, aspirin is used extensively by GPs in secondary prevention: it is used to prevent heart attack, mini-stroke and major stroke. It's also quite extensively used by GPs in the prevention of clotting disorders, such as deep vein thrombosis. It is given to people on long-haul flights, for example, to prevent clotting of the blood."
Its use, by GPs, in primary prevention, however, is questionable, according to Dr Daly. He says this is because of the possibility of side effects, such as gastro-intestinal problems in the elderly.
"There has been a reported increase in subdural haematoma in elderly people. This raised the possibility that it is associated with increased use of aspirin and other anticoagulants in preventing stroke and heart disease.
"Generally, doctors are wary of extensive use of aspirin as primary preventative, because we are always weighing up the risk benefit of any drug."
Overall though, GPs find it extremely useful, very simple, and inexpensive. And doctors have lots of experience in its use, says Dr Daly.
Dr Martin Quinn: Consultant cardiologist, St Vincent's University Hospital, Dublin, is in no doubt that aspirin works.
"It's a wonderful drug - extensively used in cardiovascular disease, such as heart attack and stroke. It is of tremendous benefit in secondary prevention. And it's generally safe - the benefits far outweigh the risks."
And should it be used for primary prevention in the high-risk category?
"We do use it, but the evidence is not quite as strong. I would tend to recommend it for high-risk patients for primary prevention, but I would inform the patients of potential bleeding. I would discuss the risk-to-benefit ratio. A number of studies carried out in the States and the UK show both negative and positive effects, but the general consensus is that there is benefit in certain situations."
Dr Quinn points out that the American Heart Association and the European Cardiac Society recently issued recommendations on primary and secondary prevention, several of which refer to aspirin use.
The benefits are evident, he says: "If we give 50 patients who have had a heart attack an aspirin, we will prevent one of them dying in 30 days."
He believes, however, there is a bigger and more pressing issue facing health professionals in the form of aspirin resistance, which he has researched.
"Aspirin resistance is defined in many different ways - the medicine is expected to inhibit clotting abilities but it differs from person to person. Up to 20 per cent of patients with acute heart attack fail to achieve levels of platelet inhibits (clotting).
"It appears that aspirin resistance may be clinically relevant and may increase the risk of subsequent heart attack or stroke for the patient.The issue is, what is aspirin resistance? Is it real? Do we pay attention to it? Do we change dose, combine it with other drugs or something else?"