Update on mild cognitive impairment.

Mild cognitive impairment (MCI) refers to persons whose memory or other cognitive abilities are not normal, but who do not have clinically diagnosed dementia. MCI has received considerable attention in the medical literature over the past few years. There were 63 original reports in the English language literature with the term "mild cognitive impairment" in the title in 2001 and 2002, in contrast to only 26 articles in the prior decade. Although criteria for MCI are not a matter of secure agreement, a consensus is emerging that MCI is common, is associated with significant mortality and morbidity, particularly the development of AD, and is due, in large part, to the same pathologic processes responsible for Alzheimer's disease (AD). Current research efforts are geared towards understanding factors that contribute to the development of dementia among persons with MCI and towards intervention studies aimed at preventing the development of dementia among persons with MCI.