Mild Cognitive Impairment - Is It Forgetfulness Or Dementia: Alzheimers

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Mild cognitive impairment

Mild cognitive impairment (MCI) is considered a transitional state between normal forgetfulness and dementia. At least one cognitive (thinking) domain — usually memory — is below normal or in decline. When memory is affected, the condition is called amnesic MCI. Although some people with MCI remain stable or even improve, studies show that the majority, especially those with amnesic MCI, eventually develop dementia.

Researchers who examined brain tissue removed during autopsies have provided evidence that certain telltale anatomical changes may underlie this progression. As reported in the Archives of Neurology in 2006, the researchers found that the brains of people with amnesic MCI have more neuritic plaques (clumps of degenerating neurons) and neurofibrillary tangles (abnormal twisted fibers inside neurons) than normal, but not as extensive as the pathology characteristic of Alzheimer's. About 10%–15% of people with MCI progress to dementia each year. MCI becomes more common with age and affects 3%–22% of people over age 65.

A person who has MCI is able to carry on daily activities without difficulty, but a particular subset of cognitive skills may be diminished. In particular, someone with MCI may show some of the following signs:

• Increasing difficulty with memory or, in some cases, subtle problems in other cognitive domains, such as language, attention, spatial skills, and problem solving

• Confirmation of impairment on neuropsychological tests, often manifesting as difficulty with learning and delayed recall of information compared with others of the same age and education level. In some cases, memory is normal but is less reliable than it used to be.

Last updated:	January 23, 2007