The impact of mild cognitive impairment on functional abilities in the elderly.

Mild cognitive impairment (MCI) covers a spectrum of cognitive impairment, bordered by normal cognitive performance on one end and frank dementia on the other. How wide the net for MCI is cast will affect the prevalence and severity of its functional consequences. Many studies suggest that MCI is an early stage of Alzheimer's disease. Therefore, investigation of the functional impact of MCI offers an important opportunity to examine the quality-of-life impact of a prodromal stage of Alzheimer's disease. In this review, the authors examine the nosology of the condition, the subjective experience of having an MCI diagnosis, and cross- sectional and prospective studies that have examined the topic.