ASSOCIATION IS NOT CAUSATION.
Now that I’ve cleared that up, let us examine the paper causing the headlines today . “Over 65s who take more than one medicine should consult their doctors. Taking some commonly used medications in combination leads to an increased risk of death or brain impairments in over 65s” says the Guardian. The Telegraph goes a bit further. “Combinations of popular drugs could prove fatal in elderly.” The actual paper, which is in the Journal of the American Geriatrics Society, is apparently about to go up online (as I write, it does not even appear as an abstract there or on the University of East Anglia website; it’s just a press release and a list of the offending drugs.)
Basically, through looking at a database of 13,400 older people living at home or in carehomes, they found a higher risk of cognitive impairment or death the more anticholinergic drugs were taken.
Does this mean that the medications caused the cognitive decline or death?
No. It means that if you have high blood pressure, dementia, chronic pain, depression, heart failure or angina (which the medications were prescribed for in the first place) then you have a higher risk of death. This isn’t surprising. What we really need to know is, if you have heart failure for example, you are better off taking medication than not. There are many studies looking at these kinds of questions and research which aims to answer this. But in this study, you can’t conclude that the prescriptions are causing more deaths; this study cannot answer than question.
The ‘cognitive decline’ the researchers found relating to anticholinergic drug use was actually small, between half a point and a point of the MMSE examination, a 30 point tool used to measure cognitive function. In fact, a score of above 25 is generally considered normal, and the lowest score in the study was 24.9.
Of course, people should not be on drugs they don’t need, or where the balance of risk is unfavourable. It isn’t usually that straightforward, which is another reason for thoughtful, evidence based, discursive prescribing; and not reflex protocols.