Outcome of mild cognitive impairment comparing early memory profiles

Area of Science:

• Neuroscience
• Gerontology
• Cognitive Psychology

Background:

• Identifying predictors of cognitive decline in amnestic mild cognitive impairment (aMCI) is crucial for detecting prodromal dementia.
• This study investigates whether preserved recognition memory in aMCI predicts a more stable clinical course.

Purpose of the Study:

• To test the hypothesis that aMCI patients with better recognition skills, despite similar delayed recall deficits, exhibit greater functional stability.
• To identify prognostic markers for cognitive trajectory in aMCI.

Main Methods:

• A cohort of 210 aMCI patients were followed for 36-100 months.
• Patients were stratified based on their initial recognition memory discrimination index (DI) from the Hopkins Verbal Learning Test (DI ≥ 8 vs. < 8).
• Demographic, neuropsychological, and neuroimaging variables were compared, along with progression to dementia versus stability.

Main Results:

• 37% of aMCI patients progressed to dementia.
• The group with higher DI scores (n=107) showed a conversion rate of 21.5%, significantly lower than the lower DI group (n=103; 52.4%, p < 0.0001).
• Progression to dementia occurred significantly later in higher DI patients (50 months vs. 26 months, p < 0.0001). Multivariate analysis identified DI, delayed recall, age, and family history as key predictors.

Conclusions:

• Amnestic mild cognitive impairment patients with better baseline recognition memory have a more favorable prognosis.
• Identifying these individuals can help isolate aMCI cases in earlier prodromal stages of Alzheimer's disease (AD).
• This stratification may facilitate the selection of more homogeneous patient groups for clinical trials.