The relationship between atrophy of the medial temporal area and daily activities in older adults with mild cognitive impairment

Background and aims: Many studies have suggested that social network, leisure activity, and physical activity can have protective effects against dementia and Alzheimer’s disease. However, previous studies have not examined the relationship between daily activities and brain atrophy in older adults. This study aimed to explore what kind of daily activities were associated with atrophy of the medial temporal area including the entorhinal cortex (MTA-ERC) in older adults. Methods: In total, 122 older adults (aged 65 and over) with subjective memory complaints or a Clinical Dementia Rating of 0. 5 underwent magnetic resonance imaging, and MTA-ERC atrophy was assessed by the voxel-based morphometry method. Based on magnetic resonance imaging data, the subjects were divided into atrophy and non-atrophy groups. Daily activities were assessed using a 20-item questionnaire (e.g., instrumental activities of daily living, social activities), and we compared activity participation between the groups. Results: The atrophy group (n=37) showed significantly lower participation in 4 out of 20 activity items (cleaning, intellectual activity, culture lessons, and using a personal computer) than the non-atrophy group (n=85). Summed scores of these 4 items (range from 0 to 4) were significantly associated with MTA-ERC atrophy even after adjustment for age, sex, education status, and Mini-Mental State Examination score. Conclusions: In conclusion, MTAERC atrophy was associated with cognitive activities or household-related activities requiring planning.