Is it early Alzheimer's or mild cognitive impairment Doctors left baffled by new guidelines
Confusion: The line between mild impairment and early Alzheimer's disease has blurred, a doctor claims (posed patient)
Doctors are struggling to diagnose whether their patients have early Alzheimer's disease or simply mild cognitive impairment, a report has warned.
Dr John Morris, from Washington University in St Louis said new guidelines for diagnosing mental decline has caused confusion among both medical staff and patients.
The revised definition of a brain condition called mild cognitive impairment means that many people now considered to have mild Alzheimer's disease could easily be given that diagnosis instead.
'There's been a lot of
controversy… about the whole classification called mild cognitive
impairment,' said Dr Peter Whitehouse, from
Case Western Reserve University School of Medicine in Cleveland, who
wasn't involved in the study.
major issue since the beginning (has been) defining its boundaries.
Inventing a label like this creates
Mild cognitive impairment was originally
diagnosed in people with memory problems but no other difficulties in
thinking and reasoning abilities or in completing daily activities.
But that definition has morphed over time to include more people, and in recent recommendations made for the National Institute on Aging and the Alzheimer's Association, it now covers people with some trouble doing household chores and hobbies.
Those functional problems have traditionally been part of an early Alzheimer's diagnosis.
Dr Morris said this caused too much confusion because most cases of mild cognitive impairment really are the first signs of Alzheimer's.
Other cognitive problems could be due to a stroke, certain medications or thyroid problems, he said – things that doctors could find explanations for if they kept looking and don't require a separate diagnosis or label.
Dr Morris examined data on more than 17,000 people evaluated for Alzheimer's disease at 33 different centers between 2005 and 2011, including about 6,000 who were originally diagnosed with full-on Alzheimer's or mild dementia related to Alzheimer's.
Those people were 75 years old when they were tested, on average, according to the report published in Archives of Neurology.
Dr Morris determined that based on the new definition of mild cognitive impairment almost every person with 'very mild' Alzheimer's disease dementia could be diagnosed with mild cognitive impairment instead.
That was also the case for more than 90 per cent of people with 'mild' Alzheimer's disease.
The overlap could lead to a lot of subjective decisions on the part of doctors, when it comes to who has early Alzheimer's and who has mild cognitive impairment.
Dr Morris said it was key to get the correct diagnosis because if it is Alzheimer's the patient should be asked to make decisions about their care while they still had the ability to do so.
However, Creighton Phelps, head of the Alzheimer's Disease Centers Program at the National Institute on Aging, said many researchers still think there's a point in between normal thinking and functioning and Alzheimer's dementia that deserves its own category.
'What other experts say is, you should not be calling it dementia too early, until you're absolutely sure about it,' he said.