Re: Targets for dementia diagnoses will lead to overdiagnosis
Editor's note: This response has been edited since original publication. In its original version, the response complained of the absence of an author's competing interests, which has since been traced back to clerical rather than respondent error.
I am grateful to Prof Burns and colleagues for responding to my article, and would like to reply in turn.
It is incorrect to say that I am of the opinion that the ‘current interest in dementia will lead to harm and over-diagnosis.’ Indeed I welcome the much needed attention dementia care has received in recent years; it is specific policies that I am concerned about, and in particular the entirely novel concept that we should set targets for diagnosis rates. I am disappointed that Prof Burns chose not to address this central theme of the article, or indeed acknowledge that there might be both ethical considerations and potential harms in such a policy.
Prof Burns feels that, as the estimates of dementia prevalence suggest that nearly half the people with dementia are as yet undiagnosed, this is not the time to consider the possibility of over-diagnosis. This seems complacent since not only are the estimates outdated and in dispute, but the presence of undiagnosed persons in the community is of no consequence to an individual who has been over-diagnosed – the presence of one does not exclude the possibility of the other. Furthermore, we have to consider the effects of this policy many years down the line when diagnosis rates may well be much higher. The fact that there is to be an independent reassessment of the prevalence data is to be welcomed, but the old figures continue to be used while this is awaited. The launch of the latest version of the calculator means that each practice has been given new figures; my own practice has had its diagnosis rate changed from 126.7% to 59.6% - does this not demonstrate how meaningless these figures are at the level of a single practice?
The case of Mrs Jones is clearly fictional, but the influence of policy on the diagnostic process is not. One of my own patients was diagnosed with Alzheimer’s disease on the basis of an MRI scan alone, in the absence of supportive cognitive testing. When I challenged the psychiatry ST4 who made the diagnosis he seemed unconcerned that he might be wrong, and stated that the emphasis was to diagnose dementia early anyway. He had been influenced by the prevailing view in dementia care and neglected to give proper consideration to the person in front of him, whose diagnosis has since been refuted. The greatest risk of over-diagnosis is not the occasional human inaccuracy, but an ethos or policy which involves unrecognised harms.
It is disingenuous to imply that I have singled out dementia care as part of a wider attack on financial incentives in primary care. What is concerning about dementia policy is that financial incentives have been applied for the first time to the making of a diagnosis. I agree that ‘appropriate and timely diagnosis’ is important in achieving support for patients with dementia, but in my experience as a GP ,support frequently does not follow diagnosis; my most recently diagnosed patient, for example, was deemed to be unsuitable for anticholinesterase medication, and so discharged after initial assessment without any follow-up or support whatsoever. Policies that improve support for patients and their carers would have my full backing.
Competing interests: I am the author of the article, my declaration can be found with the article and also on www.whopaysthisdoctor.org