New Definition of Mild Cognitive Impairment Blurs Distinction between MCI Early Alzheimers

A recent article in Neurology reported that a revised definition of mild cognitive impairment has been developed by a work group from the Alzheimer's Association and National Institutes of Aging. The previous distinction between mild cognitive impairment (MCI) and early stages of Alzheimer's disease relied on this difference: in MCI, the person's cognitive deficits, like memory, for example, did not interfere with activities of daily living (which includes skills such as dressing, bathing, eating meals).

Historically, MCI has been thought of as the dysfunction that may occur between normal cognition and the development of a dementia such as Alzheimer's. With this new definition, the line between Alzheimer's and MCI is blurred since both can now exhibit cognitive problems and daily functioning challenges.

One reason the group is making this change is because they found that even though a diagnosis of MCI required a person to exhibit normal functioning in daily life, research demonstrated that many people with MCI were experiencing impairments in their activities of daily living.

The take-away? Some people already diagnosed as having Alzheimer's or another dementia in the early stages may now fit the criteria for MCI instead. While this change gives the clinician more authority to use his or her judgment in diagnosing, it also reduces uniform definitions of both MCI and Alzheimer's since the previous boundary of impairment in daily living skills - that key distinction - has been removed.