Rapid-response reply to Bad medicine: modern medicine.
Soon all those . . .
From his frontline, Dr Spence states that he “fears soon all those with even mild cognitive impairment will be labelled with dementia.” Is this just another example of fear mongering by one of the most challenging feature writers for the British Medical Journal? Only time will perhaps tell, but for now let us consider what several authorities say about this subject.
Dr Allen Frances, chair of the DSM-IV Task Force has been a leading and vocal critic of the various draft releases of the forthcoming DSM-V classification. His very real fear is that that “DSM-V will cause further epidemics of ‘over-diagnosis’”. One area specific to such concern is the DSM 5 proposal to include Minor Neurocognitive Disorder as a “presumed prodrome” to Alzheimer’s Disease. Like me Dr Frances believes that biological testing for prodromal AD will be an important milestone in the clinical application of neuroscience. However to do so effectively we need to better understand the pathology behind Alzheimer’s disease. It is still the case that the details of the pathological cascade are not fully understood, far less the link with normal ageing processes and the role of environmental triggers.
Dr Frances believes that minor neurocognitive disorder “has necessarily to be based exclusively on extremely fallible clinical criteria that will have unacceptably high false positive rates – surely exceeding 50 percent. Why scare half the people taking the tests unnecessarily, especially when there is no effective treatment even for those who are true positives”’
In the Lancet Neurology, experts in the field of Alzheimer’s disease have attested that, whilst progress has undoubtedly been made on biological markers, much remains to be done in standardizing these tests, determining their appropriate set points and patterns of results, and negotiating the difficult transition from research to general clinical practice.
I cannot then reassure Dr Spence regarding this aspect of his “contagion of iatrogenic harm.” Furthermore, surely we can agree with Dr Spence that good medical practice should allow questioning of itself. Given such request, a blog article by Jesse Ballenger of March 2010 is worth reading: though two years old, it does not seem out of date.
“The draft of DSM-V does propose significant changes that, while well-intentioned, may greatly extend the medicalization of aging and worsen the stigma of age-associated cognitive decline.” 
This week’s BMJ (22 March 2013) gives over its Editorial to DSM-V:
DSM-5 and the rough ride from approval to publication:
“Rarely can any medical publication of any sort have so swiftly divided physicians and commentators. There is already enough analysis on this manual to fill several journals several times over, so I don’t intend to add a great deal. But given the incredible heat DSM-5 is already generating, the process of its creation and dissemination at the very least seems to demand serious attention, while the proposal to have the manual evolve as new evidence appears is a clear improvement on a once-a-decade bombshell.”
 BMJ2012;344:e2346 Bad medicine: modern medicine. Published 28 March 2012
 Frances, A. DSM 5 Minor Neurocognitive Disorder. Psychology Today. 16 Feb 2012
 Giorgio Giaccone , Thomas Arzberger, Irina Alafuzoff, Safa Al-Sarraj, Herbert Budka, Charles Duyckaerts, on behalf of the BrainNet Europe consortium New lexicon and criteria for the diagnosis of Alzheimer’s disease The Lancet Neurology, Volume 10, Issue 4, Pages 298 – 299, April 2011
 Ballenger, J. DSM-V: Continuing the Confusion about Ageing, Alzheimer’s and Dementia. H-Madness blog 19 Mar 2010