The Importance of Alzheimer Disease Assessment Scale-cognitive Part in Predicting Progress for Amnestic Mild Cognitive Impairment to Alzheimer Disease

Abstract

The aim of this study was to verify the usefulness of Alzheimer Disease Assessment Scale-cognitive subscale (ADAS-Cog), in screening participants at risk of developing Alzheimer disease (AD) among populations with amnestic mild cognitive impairment(aMCI). 98 outpatients with aMCI were recruited. Participants were revaluated after 1 year: 44 (44.9%) were progressed to AD (progressors), while 54 (55.1%) did not convert (nonprogressors MCI). At baseline, cognitive performances were more impaired in progressors assessed by MMSE and by a neuropsychological battery. When tested with the ADAS-Cog subscale, the 2 groups of participants at baseline, progressors, and nonprogressors MCI, were significantly different regarding total score, memory, and nonmemory subitems. Considering a cutoff of 9.5 total score, adjusted for education, ADAS-Cog subscale showed a good performance (area under the curve = 0.67; sensitivity = 0.62%; specificity = 0.73%) in predicting conversion from aMCI to AD. Progressors aMCI were characterized at baseline by a greater cognitive impairment. ADAS-Cog subscale is a useful and brief cognitive assessment tool to screen aMCI participants converting to AD within 1 year.