Aspirin is the most widely used medicine in the world, found in bags and cabinets as a quick fix for ailments ranging from headaches to arthritis. But should you also be using it as a preventive treatment?
This question is prompted by recent studies looking at whether aspirin protects against heart disease and bowel cancer. But the conclusions they draw seem contradictory. Years ago, low-dose aspirin was found to cut the risk of heart disease. But recently, researchers reported in The Lancet that in healthy people, the risk of internal bleeding outweighed its heart-protecting benefits.
According to the British Heart Foundation and Diabetes UK's new guidelines, unless you actually have heart disease — not just a high risk of getting it — you shouldn't take a daily aspirin.
But recent research from Oxford University showed that a low-dose aspirin (a quarter of a normal aspirin), taken every day for five years, is enough to cut the risk of developing bowel cancer by 25 per cent. This study has prompted some scientists to recommend that everyone above 45 should take a small daily dose.
So, should you take it or not? Let's find out from the experts.
What's so good about aspirin?
Aspirin works by thinning your blood, making it less likely to form artery-blocking clots. High cholesterol, stress or obesity trigger inflammation in the blood vessels.
This inflammation makes the cells in the blood (platelets) spiky, so they clump together, forming clots. Aspirin damps down the inflammation, so platelets are less likely to clump.
If it's good, how can it be dangerous?
Aspirin blocks signals telling clotting agents such as fibrinogen to go to work. So, if you start to bleed in a delicate area such as the stomach or the brain, your blood-clotting system won't be as effective, which could be disastrous.
Until recently, experts believed that for healthy people, the benefit of reducing the risk of heart disease outweighed this risk.
However, alarm bells starting ringing in May 2009 after Professor Colin Baigent, of Oxford University's Clinical Trials Service Unit, published his research in The Lancet. "It is only in the past couple of years that we have been able to look at the risk/benefit with reliable data," he says. "Now we can see the balance of benefit and risk is really very marginal."
Since then, there have been many reviews saying healthy people shouldn't take aspirin for their heart, because the risk of bleeding is too great: 250 people have to take aspirin for one healthy person to avoid a heart attack but one person will also suffer dangerous internal bleeding as a result.
Aspirin can also damage the stomach lining and cause ulcers, as it can reduce the amount of mucus protecting the stomach walls, allowing stomach acid to be able to eat away at the lining.
Can I take it to avoid heart attacks?
Unless you have heart disease, you shouldn't take aspirin. But not all agree. The British Hypertension Society advises people whose risk of cardiovascular problems is more than 20 per cent over ten years to take aspirin.
In fact, Good Health has found that the number of prescriptions for low-dose aspirin has dropped only slightly since Baigent's research in The Lancet.
Some GPs are unhappy about the sudden change of direction.
"We GPs have large numbers of patients on the ‘standard therapy' of aspirin as a result of following guidelines that were supposedly based on the best evidence," wrote Newport GP Dr Sam Lewis recently in the British Medical Journal.
What about bowel cancer?
It's still too early to recommend that everyone takes aspirin. The latest research showed the numbers who benefited were small. Around 2.5 per cent of those who took aspirin developed colon cancer; this compared with 4 per cent not taking the drug. The question is: Did this benefit outweigh the bleeding risk? It will need a big trial to find out.
What if cancer runs in my family?
"We would recommend taking it only if you are at two-and-a-half times greater risk of bowel cancer than the general population," says Professor Dion Morton, a colorectal surgeon at University Hospital Birmingham. This means if two of your immediate relatives — parents or siblings — have had colorectal cancer or if one immediate relative below 45 has had it.
So do I need aspirin?
- The basic rule is to take a daily pill in the following cases:
- If you are known to be at risk of heart attack, as you've already had one; or angina; or blocked arteries tackled by angioplasty.
- If you are at two-and-a-half times greater risk of bowel cancer than the general population.
0 comments