To present a general overview of the etiology, definition, and prevalence of mild cognitive impairment (MCI), as well as outline possible treatment strategies.
DATA SOURCES: A MEDLINE search was conducted for relevant references generated from 1990 to 2000 concerning MCI, mild to moderate Alzheimer disease (AD), and therapeutic strategies. Several books were also used in the compilation of data for this review, as well as the authors' experience in designing and conducting MCI trials.
DATA EXTRACTION: All of the references listed were assessed, and all relevant information was included in this review.
DATA SYNTHESIS: Forgetful individuals most likely to develop AD have a condition known as MCI previous to their development of dementia. This condition is hallmarked by memory impairment that is abnormal for the individual's age and educational level. While not all individuals with MCI develop AD, it is apparent that the condition can serve as a potential marker for early onset of AD.
CONCLUSIONS:
As many clinicians can attest, occasional forgetfulness is a common aspect of the aging process. Eventually, however, a large portion of forgetful individuals, especially those with MCI, will be diagnosed with AD or some other form of dementia. Indeed, many researchers have suggested that MCI should be regarded as incipient AD and that these individuals would benefit from drug therapy. Thus, MCI screening may be beneficial in terms of both early AD intervention and perhaps even AD prevention.
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