Heather E Whitson1,2,3, Guy G Potter2,4,5, Jody A Feld6, Brenda L Plassman2,4,5, Kelly Reynolds2, Richard Sloane2, Kathleen A Welsh-Bohmer2,4,5. 1. Department of Medicine (Geriatrics), Duke University School of Medicine, Durham, NC, USA. 2. Center for the Study of Aging and Human Development, Duke University School of Medicine, Durham, NC, USA. 3. Durham VA Geriatrics Research Education and Clinical Center (GRECC), Durham, NC, USA. 4. Joseph and Kathleen Bryan Alzheimer's Disease Research Center, Duke University School of Medicine, Durham, NC, USA. 5. Department of Psychiatry and Behavioral Sciences, Duke University School of Medicine, Durham, NC, USA. 6. Department of Orthopedic Surgery, Doctor of Physical Therapy Division, Duke University School of Medicine, Durham, NC, USA.
Abstract
BACKGROUND: Dual-task paradigms, in which an individual performs tasks separately and then concurrently, often demonstrate that people with neurodegenerative disorders experience more dual-task interference, defined as worse performance in the dual-task condition compared to the single-task condition. OBJECTIVE: To examine how gait-cognition dual-task performance differs between cognitively normal older adults with and without an APOE ɛ4 allele. METHODS: Twenty-nine individuals ages 60 to 72 with normal cognition completed a dual-task protocol in which walking and cognitive tasks (executive function, memory) were performed separately and concurrently. Fourteen participants carried APOE ɛ4 alleles (ɛ3/ɛ4 or ɛ2/ɛ4); fifteen had APOE genotypes (ɛ2/ɛ2, ɛ2/ɛ3, or ɛ3/ɛ3) associated with lower risk of Alzheimer's disease (AD). RESULTS: The two risk groups did not differ by age, sex, race, education, or gait or cognitive measures under single-task conditions. Compared to low risk participants, APOE ɛ4 carriers tended to exhibit greater dual-task interference. Both the memory and executive function tasks resulted in dual-task interference on gait, but effect sizes for a group difference were larger when the cognitive task was executive function. In the dual-task protocol that combined walking and the executive function task, effect sizes for group difference in gait interference were larger (0.62- 0.70) than for cognitive interference (0.45- 0.47). DISCUSSION: Dual-task paradigms may reveal subtle changes in brain function in asymptomatic individuals at heightened risk of AD.
BACKGROUND: Dual-task paradigms, in which an individual performs tasks separately and then concurrently, often demonstrate that people with neurodegenerative disorders experience more dual-task interference, defined as worse performance in the dual-task condition compared to the single-task condition. OBJECTIVE: To examine how gait-cognition dual-task performance differs between cognitively normal older adults with and without an APOE ɛ4 allele. METHODS: Twenty-nine individuals ages 60 to 72 with normal cognition completed a dual-task protocol in which walking and cognitive tasks (executive function, memory) were performed separately and concurrently. Fourteen participants carried APOE ɛ4 alleles (ɛ3/ɛ4 or ɛ2/ɛ4); fifteen had APOE genotypes (ɛ2/ɛ2, ɛ2/ɛ3, or ɛ3/ɛ3) associated with lower risk of Alzheimer's disease (AD). RESULTS: The two risk groups did not differ by age, sex, race, education, or gait or cognitive measures under single-task conditions. Compared to low risk participants, APOE ɛ4 carriers tended to exhibit greater dual-task interference. Both the memory and executive function tasks resulted in dual-task interference on gait, but effect sizes for a group difference were larger when the cognitive task was executive function. In the dual-task protocol that combined walking and the executive function task, effect sizes for group difference in gait interference were larger (0.62- 0.70) than for cognitive interference (0.45- 0.47). DISCUSSION: Dual-task paradigms may reveal subtle changes in brain function in asymptomatic individuals at heightened risk of AD.
Entities:
Keywords:
Aging brain; cognitive performance; cognitive reserve; dementia; diagnosis; early detection; motor interference; phenotype; risk; stress test
Authors: J K Longhurst; J L Cummings; S E John; B Poston; J V Rider; A M Salazar; V R Mishra; A Ritter; J Z Caldwell; J B Miller; J W Kinney; M R Landers Journal: J Prev Alzheimers Dis Date: 2022