Mild cognitive impairment and the neuroanatomical changes associated with progression to dementia of the Alzheimer's type.

摘要

Using longitudinal MRI volumetry we examined the relationship between the degree of cerebral atrophy and cognitive function in Mild Cognitively Impaired (MCI) subjects during the progression to Dementia of the Alzheimer's type (DAT). We used these patterns of atrophy to examine the Dichotomous Groups and Accelerated Aging theories of progression to DAT. We acquired MRI scans on 20 subjects with Mild Cognitive Impairment (MCI), 3 subjects with DAT, and 19 normal elderly controls. Scanning was carried out at two times with an average of 73 months between scans. At follow-up, 10 of the MCI subjects had progressed to dementia (Progressors) while 10 had remained stable (Non-Progressors). We found that the Progressors had a significant increase in medial temporal atrophy between Time 1 and Time 2, while the Non-Progressors remained stable. This data supports the Dichotomous Groups theory. Cognitively we found that delayed verbal recall followed the same pattern of change as medial temporal atrophy, but that language ability did not follow the same pattern of change as lateral temporal atrophy.