Researchers who tested more than 4,000 elderly people across Europe found that those who took the drug every day were twice as likely to be diagnosed with late stage age related macular degeneration as those who did not.
While the study provided no evidence of a causal link between aspirin and the condition, experts are now examining whether a regular dose somehow exacerbates the disease.
During a recent major study, researchers based in Holland found that of 839 people who took aspirin each day around 4 per cent had an advanced form of the disease called wet macular degeneration, which leads to the most profound blindess.
In comparison, just two per cent who took aspirin less frequently had the same type of macular degeneration.
Does anyone see the big problem with this study?
In fact, there are two big problems.
The first is the sample size. Normally, you’d think 839 people would be enough to be confident about the results. But look at the size of the effect. Four percent? That means we’re not talking about 839 people, we’re talking about 33.56 people.
Yes, you’d expect to find just 16.78 people with this type of macular degeneration in the same sample size. But, are you really willing to give up potentially life-saving aspirin on the basis of 16 people in one study? You shouldn’t.
There’s another huge problem, and that is the types of people who use aspirin every day of their lives are likely very different from the types of people who live a long time without using aspirin daily. Those on the aspirin, along with cardiovascular disease, are also more likely to have diabetes, exercise less, eat less healthy or weigh more than the non-aspirin group. And that’s before genetics gets thrown into the works.
This is an apples-oranges sampling problem. It can’t be taken seriously and should not be posted around the internet like it’s a meaningful study. I doubt very much you could accurately control for all the variables that separate habitual aspirin users from those who don’t even with a much larger sample size.
And how, in this study, with just 17 people above and beyond the expected level of macular degeneration, could you control for even one factor, that of heart disease?
It’s possible there is some underlying mechanism and aspirin takers should be aware of the problem. But they should also be aware that the real risk of suffering this consequence is at most 1 in 50, and it’s not lethal. Not taking aspirin can be very lethal. Be smart kids. Do the math.
- Regular aspirin users at higher risk of sight problems, research suggests (telegraph.co.uk)
- Daily Aspirin Tied to Risk of Vision Loss (nlm.nih.gov)
- Is macular degeneration terminal (wiki.answers.com)