Emergence of Mild Cognitive Impairment in Late Middle-Aged Adults in the Wisconsin Registry for Alzheimer's Prevention

作者：Koscik Rebecca L^*; La Rue Asenath; Jonaitis Erin M; Okonkwo Ozioma C; Johnson Sterling C; Bendlin Barbara B; Hermann Bruce P; Sager Mark A

来源：Dementia and Geriatric Cognitive Disorders, 2014, 38(1-2): 16-30.

DOI：10.1159/000355682

• Mild cognitive impairment
• Longitudinal assessment
• Cognition
• Robust norms

Aim: It is difficult to reliably detect the earliest signs of Alzheimer's disease (AD)-associated cognitive impairment. Our aim was to compare 3 psychometric methods of identifying amnestic mild cognitive impairment (aMCI) in a middle-aged longitudinal cohort enriched for AD risk. Methods: Wisconsin Registry for Alzheimer's Prevention (WRAP) participants with 3 waves of cognitive assessment over approximately 6 years were coded as meeting each of 3 psychometric aMCI definitions: (a) 'aMCI standard-baseline' used published norms to establish cutoffs for baseline performance; (b) 'aMCI robust-baseline' applied WRAP-specific robust norms to baseline, and (c) 'aMCI robust-multiwave' applied these robust norms across 3 waves of assessment. Each group was compared to a cognitively healthy subset. Results: Half the aMCI standard-baseline and one third of the aMCI robust-baseline group reverted to normal ranges at follow-up. Only the aMCI robust-multiwave method had an aMCI x age interaction showing significantly worse age-related memory declines in the aMCI group compared to the cognitively healthy group over 6 years of follow-up. Conclusion: Both cross-sectional methods showed instability over time, with many reverting to normal performance after baseline. The multiwave approach identified a group who showed progressive memory declines over 3 visits. Being able to detect progressive decline in late middle age is a critical step in improving prevention efforts.

• 出版日期2014