Views & Reviews From the Frontline

Bad medicine: dementia

BMJ 2012; 344 doi: (Published 01 June 2012) Cite this as: BMJ 2012;344:e3859
  1. Des Spence, general practitioner, Glasgow
  1. destwo{at}

As our physical bodies give out we look in horror into the mirror, seeing our father or mother looking back at us. We comfort ourselves that at least we have our own personality, memories, and individuality. But to lose these is to lose everything; I fear dementia above all other illnesses. Due to an ageing population there is talk of a pending national crisis in dementia, and this particular medical bandwagon is beginning to play politically.1

There has been much talk of early diagnosis, memory clinics, training, screening, and criticism that 75% of cases go unrecognised.2 3 Advocacy groups use familiar rhetoric, demanding the “right to a diagnosis” and talking about a “treatment gap.” The internet is spawning online testing questionnaires to aid and promote self diagnosis.4 The National Institute for Health and Clinical Excellence in turn suggests treatment even for those with mild dementia.5 Underdiagnosis is presented as the problem. Perhaps this is all fair and reasonable, for such an important and pressing illness.

But what about the potential for overdiagnosis of dementia? A concern neither researched nor acknowledged. Mild cognitive impairment (MCI), associated with impaired memory, is reported in 22% of those over 75.6 But MCI is clinically difficult to distinguish from mild dementia, even using the latest imaging and testing. And clinicians stung by media criticism will make the diagnosis rather than be accused later of misdiagnosis. So here is the problem: dementia is a devastating diagnosis, progressive, untreatable, and leading to dependence and institutionalisation. Overdiagnosis of dementia risks misery and the theft of wellbeing from millions of old people and their families. Like Terry Pratchett, many people would vow to take their own life with such a diagnosis.

What about the evidence for early diagnosis? Drug treatments result in a 2.7 improvement out of 70 on the Alzheimer’s disease assessment scale: cognition (ADAS-Cog) score,7 a difference so small as to be clinically undetectable.8 Drugs are not disease modifying, having no impact on rates of institutionalisation and disability9; there is no so called treatment gap. Screening and more testing will only ensnare the anxious rather than the afflicted, and cannot be justified. There is an absence of evidence that early diagnosis changes anything—this is not fatalism but realism.3 Predictably perhaps, big pharma lurks behind those advocating early diagnosis.10

There is much we can do, however. Value the elderly and their carers. End society’s vacuous obsession with youth culture. Make advance directives the norm, and tackle the thoughtless prolongation of life with the common use of percutaneous endoscopic gastrostomy and nasogastric feeding tubing. The promotion of underdiagnosis of dementia is without cognition and will lead to widespread suffering and overdiagnosis, which is bad medicine indeed.


Cite this as: BMJ 2012;344:e3859