This post is also available in: हिन्दी (Hindi)
My name is Sanjay Gupta and in my last video, I decried the over-zealous prescription of medications which may have no or limited benefit for the patient. In this video, I wanted to explore this further with respect to Aspirin which is commonly prescribed for prevention or treatment of heart disease. This video is enigmatically entitled ‘Welcome to the primary Bank of Aspirin’.
The best banks to put your money in are those which keep your money safe and give you a good return for your investment and where your returns are not eroded by excessive additional charges or fines. In the same sense the best medications to take are those that are both safe but also in the long term offer a substantial return in terms of either improving quality of life and/or an improvement in length of life.
Assessing the return in terms of quality of life is easy because you the individual can measure your quality of life and work out whether it has improved or not. Length of life is much more difficult because as an individual you will never know whether a medication has prolonged your life or not. So the only way to decide whether a medication offers good returns is to look at data that has been accrued from studies of patients just like us and use those data to decide whether the returns from taking that medication are good enough for us or not.
If we think about it, this is how we decide to invest our money in a bank. We do our research to ensure that our capital will be safe and what rates of interest we would get before parting with our hard earned cash. Unfortunately we rarely do the same with the medications that we are asked to take. We just take medications because the doctor tells us it is good for us. We rarely ever ask ‘how good’. And the incredible thing is that this answer should be easily available because all quantitative research about using numbers to tell us how good something is and yet rarely are we given the number to help us make our decision. However trying to get these numbers is anything but easy because the numbers that really matter are often concealed in complex statistics and relative percentages rather than being completely transparent. In that sense, it is far easier to get numbers from bankers than it is from the pharma industry.
In this video, I wanted to try and get those numbers and put them in front of you so that you can decide for yourselves whether the numbers are good enough to justify your investment in a particular medication. As always I would like to stress that please do not make any changes to your medications without speaking with your own healthcare provider as the information I present here may not be applicable to your unique situation.
Today I welcome you to the Primary Bank of Aspirin. This is called the Primary Bank because it is only for those people who have never had a heart attack or a stroke but are looking to prevent one from happening by taking Aspirin daily. This video is not for those patients who have already had a heart attack or a stroke or stents or bypasses or some other form of vascular event who are trying to prevent a further event by taking Aspirin. For those people there exists the Secondary Bank of Aspirin which I shall talk about in a later video. So if you have never had a cardiac event or a stroke, the Primary Bank of Aspirin is the bank that you need to know about.
So firstly why even consider Aspirin.
The answer is that Aspirin is an antiplatelet agent and we know that the majority of vascular events occur because of sudden formation of blood clots within the blood vessels and therefore taking an agent which stops platelets aggregating together and forming a blood clot would seem like a great idea but what kind of returns can you expect on your investment in a daily dose of Aspirin?
Let’s look at length of life:
Does Aspirin prevent death or vascular events (i.e heart attacks or strokes) if you have no previous history of vascular events?
There have been some big trials trying to answer this:
- There was a trial called ASCEND. In this study, over 15000 patients with diabetes but no history of a cardiac or vascular event were assigned to Aspirin or placebo and they were followed up for an average of 7.4 years. At the end of the trial,l if you just counted up the number of deaths in both groups (without trying to work out why these patients died), we see that 748/7740 people died in the Aspirin group and 792/7740 people died in the placebo group and so statistically there was no real significant difference i.e taking Aspirin did not prevent you dying. So the next question to ask is that did aspirin really have no benefit at all or was in some way the benefit offset by harm? When we look at this we see that yes Aspirin use was associated with a 12% reduction in serious vascular events compared to placebo but that benefit was offset by a 29% increase in major bleeding and therefore in conclusion there was really no net benefit at all from Aspirin in this group.
- There was another study looking at this question called the ASPREE study. Here over 19000 patients who were above the age of 70 were randomised to Aspirin or placebo and after an average of 4.7 years, they found that there was no difference in major cardiac or vascular events between the two groups but there was again an excess of bleeding in the Aspirin group. Interestingly more people died in the Aspirin group compared to placebo and most of these patients died of cancer.
- A third study called ARRIVE looked at over 12000 patients (men>55; women> 60) and found that at the end of 5 years there was no difference in cardiovascular events between the two groups.
As these were different studies looking at different populations, a group of statisticians combined all the data together to try and work out the overall benefit and the overall harm from Aspirin. If you want to see the numbers for yourself please visit www.nnt.com and type in Aspirin for primary prevention of cardiovascular disease and these scientists have produced some numbers for us which allow us to work out what our return on investment will be with Aspirin. These numbers are called the numbers needed to treat i.e how many people need to take the medication and for how long to prevent one event (be that death or a heart attack or a stroke)
The number needed to treat are as follows:
Aspirin does not prevent death compared to placebo in patients who have never had a vascular event previously
You would have to treat 2000 patients for 1 year to prevent one non-fatal heart attack and you would have to treat 3000 patients for 1 year to prevent one non-fatal stroke.
For every 3333 patients Aspirin would cause a major bleed in 1 patient.
Overall you would have to treat 1667 patients on Aspirin for a year for 1 person somewhere to benefit and most importantly no one including that person themselves will ever know the identity of that beneficiary.
So in summary, the returns on your investment from the Primary Bank of Aspirin can be thought of as follows using a banking analogy:
Put 1667 pounds in the bank for 1 year for it to earn 1 pounds worth of interest and there is no guarantee at all that you would even receive that pound.
I now leave it to you to decide whether that is an investment worth making or not.
I hope you found this video useful and I would love to hear your comments.
Link to video: Welcome to the Bank of Aspirin
This post is also available in: हिन्दी (Hindi)