Title | Physical Activity and Hippocampal Sub-Region Structure in Older Adults with Memory Complaints. |
Publication Type | Journal Article |
Year of Publication | 2018 |
Authors | Siddarth, P, Rahi, B, Emerson, ND, Burggren, AC, Miller, KJ, Bookheimer, S, Lavretsky, H, Dobkin, B, Small, G, Merrill, DA |
Journal | J Alzheimers Dis |
Volume | 61 |
Issue | 3 |
Pagination | 1089-1096 |
Date Published | 2018 |
ISSN | 1875-8908 |
Keywords | Aged, Aged, 80 and over, Cognition, Cross-Sectional Studies, Executive Function, Exercise, Female, Geriatric Assessment, Hippocampus, Humans, Magnetic Resonance Imaging, Male, Memory, Memory Disorders, Middle Aged, Neuropsychological Tests |
Abstract | BACKGROUND: Physical activity (PA) plays a major role in maintaining cognition in older adults. PA has been shown to be correlated with total hippocampal volume, a memory-critical region within the medial temporal lobe (MTL). However, research on associations between PA and MTL sub-region integrity is limited. OBJECTIVE: To examine the relationship between PA, MTL thickness, and its sub-regions, and cognitive function in non-demented older adults with memory complaints. METHODS: Twenty-nine subjects aged ≥60 years, with memory complaints were recruited for this cross-sectional study. PA was tracked for 7 days using accelerometers, and average number of steps/day determined. Subjects were categorized into two groups: those who walked ≤4000 steps/day (lower PA) and those with >4000 steps/day (higher PA). Subjects received neuropsychological testing and 3T MRI scans. Nonparametric ANCOVAs controlling for age examined differences between the two groups. RESULTS: Twenty-six subjects aged 72.7(8.1) years completed the study. The higher PA group (n = 13) had thicker fusiform gyrus (median difference = 0.11 mm, effect size (ES) = 1.43, p = 0.001) and parahippocampal cortex (median difference = 0.12 mm, ES = 0.93, p = 0.04) compared to the lower PA group. The higher PA group also exhibited superior performance in attention and information-processing speed (median difference = 0.90, ES = 1.61, p = 0.003) and executive functioning (median difference = 0.97, ES = 1.24, p = 0.05). Memory recall was not significantly different between the two groups. CONCLUSION: Older non-demented individuals complaining of memory loss who walked >4000 steps each day had thicker MTL sub-regions and better cognitive functioning than those who walked ≤4000 steps. Future studies should include longitudinal analyses and explore mechanisms mediating hippocampal related atrophy. |
DOI | 10.3233/JAD-170586 |
Alternate Journal | J. Alzheimers Dis. |
PubMed ID | 29254088 |
Grant List | UL1 TR000124 / TR / NCATS NIH HHS / United States |