Executive Functions And Screening For Mild Cognitive Impairment And Alzheimers Disease: A Cross-Sectional Study

Abstract

Context: Subjective memory complaints, before mild cognitive impairment (MCI), constitute the chief symptoms during the development of Alzheimer’s disease (AD) and are generally the initial signs for identifying the disease. Objective: The objective was to explore executive functions capacities in differentiating patients with AD from those with MCI as well as from that exempt from any cognitive deficit (CO). This study enabled us to compare the cognitive and specifically executive functioning of three participant groups (AD, MCI and CO) to determine an optimal measure(s) for differential diagnosis. Methods: A total of 116 participants were recruited (32 AD, 40 MCI, and 44 CO). To estimate executive function capacities, the Clock Drawing Test (CDT), the Trail Making Test Part A and B (TMT A and B) as well as the Verbal Fluency Tests - Alphabetic (VFT-A) and Category (VFT-C) were used. To exclude patients with depression, the Geriatric Depression Scale (GDS) with cut-off score was used. Furthermore, the Mini Mental State Examination (MMSE) was used to make between groups comparison on general cognition. Results: A significant mean score difference was observed between the MCI and CO groups on all executive function measures, except for the VFT-A. In contrast to other groups, the AD group performed significantly worst on all executive function measures. Conclusion: Herein, a significant difference between AD, MCI, and CO groups on executive functioning tasks, where AD group underperformed was reported. This warrants the use of executive functioning assessment as a way to help differential diagnosis.