It has always puzzled me that medical authorities recommend conventional medicines by way of prophylaxis against disease. I had assumed, naively perhaps that medicines were designed to treat a condition or symptom, not to be used as a means of preventing disease in healthy individuals. Therefore the latest news about the risks of low-dose aspirin is somewhat unsurprising (well, to me anyway!). Much of this comes after an Italian study published in 2012 into the use of low-dose aspirin in diabetics as a means of preventing heart disease (a common risk in diabetics) has suggested that while people with diabetes are at increased risk of major bleeding, taking low-dose aspirin does not seem to increase this risk further. While reassuring, this study has some limitations and the decision whether or not to use aspirin in people with diabetes remains dependent on individual risk factors and circumstances. Whilst low-dose aspirin in secondary prevention is not controversial (ie. those who already have an existing condition which places them at a increased risk of additional or new cardiovascular events), the administration of low-dose aspirin in primary prevention is not recommended by the regulatory authority in the UK (the MHRA; the Medicines and Healthcare Regulatory Authority) as highlighted in their Drug Safety Update in 2009:http://www.mhra.gov.uk/home/groups/pl-p/documents/publication/con059813.pdf
Aspirin for Healthy People
However, there remains some confusion as to whether healthy individuals should be taking low-dose aspirin since many doctors still prescribe or recommend low-dose aspirin in those at increased risk of clots forming the blood which could lead to a heart attack or stroke. This includes individuals who:- have a high blood cholesterol level (hypercholesterolaemia)
- have high blood pressure (hypertension)
- have a family history of heart disease due to raised cholesterols levels in the blood (familial hypercholesterolaemia)
- smoke
- have diabetes
- retinopathy (damage to the retina of the eye)
- nephropathy (kidney damage)
- have had diabetes for more than 10 years
- are over 50 years old
The normal dose for aspirin when taken as a painkiller is usually 300mg and low-dose aspirin typically refer to doses in the region of 75mg. There is a strong culture of being medicated so even healthy individuals who have no symptoms or a diagnosis of a condition self-medicate as a rationale to prophylaxis. This is particularly true of statins which was granted over-the-counter (OTC) status some time ago and therefore made available to the public without a prescription. Many like me, still have huge reservations about statins being made so readily available. In the UK, we only narrowly missed the introduction of statins into our drinking water as a means of preventing the increasing incidence of heart disease (which remain one of the biggest causes of mortality in this country).
When aspirin is used to prevent cardiovascular disease, the scales tip
more toward harm. For every 10,000 people taking low-dose aspirin, seven people
will be helped—mostly by preventing heart attacks—to every four harmed. These
numbers are averages, so the risk faced by an individual depends on his or her
particular characteristics. The chance that aspirin will help rises with
additional risk factors, like older age, being overweight, smoking, and having
high cholesterol. The risk of bleeding also rises with age—but then so does the
risk of heart attacks and strokes, and the potential benefit of taking aspirin. In summary, the balance between risk and benefit of aspirin for primary prevention
is very narrow, and in many people the bleeding
risk may outweigh the potential benefits.
So what are the alternatives in primary prevention?- diet
- exercise
- lifestyle eg. cutting out smoking, reducing alcohol intake
- herbal alternatives eg. white willow, meadowsweet, garlic, ginkgo
- stress management
Aspirin: cancer-fighting benefits uncertain
Recent headlines on the merits of taking low-dose aspirin to prevent or treat cancer is fundamentally without basis simply because proper studies have not been conducted to solely examine this. The cancer-fighting benefits have been shown to be uncertain and the benefits do not outweigh the risks. In 3 research papers published simultaneously, doctors and researchers looked at cancer data that was recorded during dozens of trials testing aspirin for heart and circulatory health. They found that daily use of aspirin was linked to a drop in the short-term risk of developing cancer and could reduce both the risk of cancers spreading around the body and the risk of death due to cancer.However, given that the trials were not originally designed to see whether aspirin would reduce people's risks of cancer one cannot be sure that the drug's potential cancer-fighting benefits are not outweighed by its known side-effects. For example, aspirin can cause painful stomach irritation and there is a small but important risk of serious bleeds associated with its use. Therefore, until there have been dedicated studies, it is too soon to recommend that people should start taking daily aspirin unless it has been recommended to them by a doctor.
Overall, aspirin is a highly effective medical treatment when used appropriately, but it is not yet a drug that should be taken unsupervised on a daily basis, even at low doses. The news has understandable generated a great deal of interest in aspirin as a potential way to cut cancer risk, but it should be remembered that there are many other lifestyle changes that people can make to reduce their risk of cancer (including giving up smoking) which do not have harmful side-effects.
More information about low-dose aspirin can be found at:
