Aspirin Foundation Meeting 2013
Use of aspirin by general practitioners
Dr Tom Smith
One of the very interesting topics that has influenced both my journalism and also my practice is the use of aspirin. I’ve watched the use of aspirin developing over the last 35 years with great interest and today I’m here to present to the meeting a view of what aspirin performs in general practice today and how it may develop in the future.
Most of our elderly patients in general practice are actually taking an aspirin a day and when I talk about elderly I mean people over 50 or so. The reason for that is I live in the West of Scotland, an area which has a reputation of being the highest area in the world for deaths from cardiac disease and from strokes, that’s strokes due to thrombosis. So it was established early on that aspirin would help them but more recently there’s news that we can give aspirin also to people who are at high risk of certain types of cancer, in particular bowel cancer and possibly even breast cancer. So I’m here to hear from the meeting what has been the recent progress in these two areas. We’re already giving aspirin to our bowel cancer patients, that is patients who have been operated on for bowel cancer and for whom we would like to stop the cancer spreading. There’s good evidence that aspirin stops the spread of metastatic, that is distant spread, of cancer cells throughout the body. It does that actually by the same mechanism as we use aspirin to stop heart attacks, that is it stops things called platelets in the blood from sticking together. We know that when platelets stick together and then stick on to blood vessel walls that is the start of a clot but we’ve also heard in recent years from the people who are actually talking at this conference today that cancers spread by a cell breaking into the bloodstream, catching on to a sticky platelet and being carried distantly in the blood to somewhere else. Now, if you stop these platelets from being sticky, which is the main function of aspirin, the cancer cells can’t then stick on to them. That has two effects: first of all the cancer cell is naked, so to speak, so that the white cells in the blood recognise the cancer cell for what it is and combine together to kill it, to kill it off. Now, when the cancer cell is stuck to a platelet the white cells don’t recognise it as a cancer cell because they see the platelet protein and they leave it alone. So aspirin helps to avoid the cancers from spreading from one part of the body to the other and also helps to kill off the cancer cell directly by making it naked enough to be caught by the killer cells, the killer white cells.
Would you give aspirin to a healthy individual as prevention?
We have a group of patients in our practices to whom we are very keen to give aspirin, that is people who are deemed at high risk of heart attacks and thrombotic strokes, people who have got a strong family history of bowel cancer, people who have actually had a bowel cancer operation and we want to prevent any spread of the cancer. We’re also looking at breast cancer patients and whether, in fact, the same story is as relevant for breast cancer as it is for bowel cancer. So we’re actually giving our breast cancer patients aspirin prophylaxis as well. Now the problem is that aspirin has got a bad reputation for bleeding, for causing bleeding in the stomach and causing bleeding, that’s haemorrhagic stroke, in the brain. But what we have now got is a way of trying to reduce that risk to a minimum and what we now know is that where the stomach bleeding is concerned people whose stomachs bleed are infected usually with a bug called helicobacter and that causes tiny little ulcers in the stomach wall and if you give aspirin to these people because the platelets aren’t sticking these ulcers don’t heal and they can bleed. If they have helicobacter we give them a month’s supply of antibiotics specifically designed to kill off the helicobacter and then we give the aspirin. As for the danger of strokes, that’s bleeding strokes in the brain, we know now that if you reduce the blood pressure in people to a normal level or even slightly lower than normal level then the aspirin won’t cause haemorrhagic strokes or will reduce the chance of it to a very low degree. So we now look at the whole patient, really. If they’ve got high blood pressure we reduce their blood pressure first; if they’ve got helicobacter we get rid of that first and then we can give the aspirin so much more safely that there’s always a benefit well above the risk.
