Mild Cognitive Impairment – A Step on the Way?

Many of us as we get older suffer from temporary loss of memory – especially names of people and places –and we worry that it’s the first signs of Alzheimer’s. That’s not the case. However, it’s hard to distinguish between age-related memory lapses, what’s called ‘mild cognitive impairment’, and the early stage of Alzheimer’s disease. The differences between these conditions are strictly functional; in other words, they are revealed by the results of tests of brain function.

The most popular test is the Mini Mental State Examination (MMSE). The MMSE is a series of questions and tests, each of which scores points if answered correctly. If every answer is correct, a maximum score of 30 points is possible. People with Alzheimer's disease generally score below 24 points, depending on the severity.

Scores on the MMSE begin to decline from around age 70; but, on average, an 85-year-old with a High School education will score 26.

So where does mild cognitive impairment fit in? Maybe an MMSE score of 24 to 26 is the answer. But now the pathologists have something to say. A new report describes the results of path exams on brains from 28 people with normal cognition, 15 people with mild cognitive impairment, and 23 people with probable (i.e. ‘early’) Alzheimer’s. All the mild cognitive impairment brains showed ‘plaques and tangles” – which are hallmarks of Alzheimer’s disease – beyond what we might expect in normal aging, but not equivalent to those seen in full-blown Alzheimer’s. Furthermore, in the mild cognitive impairment brains, the plaques and tangles were confined to a specific are of the brain, unlike in Alzheimer’s, where they are widespread throughout the brain.

It looks to me that those of us over 70 – which includes me – are on a slippery slope, leading from annoying forgetfulness, to mild cognitive impairment, and if we live long enough, to Alzheimer’s. Some of us have the genes and lifestyle characteristics to allow us to step off this slope, and/or slide much more slowly. It’s worth trying the lifestyle steps, anyway!