BACKGROUND: Cognitive impairment has been shown to predict falls risk in older adults. The ability to step accurately is necessary to safely traverse challenging terrain conditions such as uneven or slippery surfaces. However, it is unclear how well persons with cognitive impairment can step accurately to avoid such hazards and what specific aspects of cognition predict stepping ability in different patient populations. METHODS: Healthy older adults (NC), patients with Mild Cognitive Impairment with only memory impairment (MCI-EF) or memory and executive function impairments (MCI+EF) and early Alzheimer's patients (AD) were timed as they performed a stepping accuracy test with increasing cognitive demand (Walking Trail-Making Test; W-TMT), which required stepping on instrumented targets with either increasing sequential numbers (W-TMT A) or alternating sequential numbers and letters (W-TMT B). RESULTS: After accounting for age and baseline walking speed, the AD and MCI+EF groups were significantly slower than the NC and MCI-EF groups on the task with the highest cognitive demand, W-TMT B (interaction effect F = 6.781, p <.0001). No group differences were noted on the W-TMT A task that was less cognitively demanding. Neuropsychological measures of executive functioning were associated with slower W-TMT B performance, whereas memory, visual attention and visual spatial skills were not (adjusted R(2) = 0.42). CONCLUSIONS: Executive function is important for stepping performance, particularly under more complex environmental conditions.
BACKGROUND:Cognitive impairment has been shown to predict falls risk in older adults. The ability to step accurately is necessary to safely traverse challenging terrain conditions such as uneven or slippery surfaces. However, it is unclear how well persons with cognitive impairment can step accurately to avoid such hazards and what specific aspects of cognition predict stepping ability in different patient populations. METHODS: Healthy older adults (NC), patients with Mild Cognitive Impairment with only memory impairment (MCI-EF) or memory and executive function impairments (MCI+EF) and early Alzheimer'spatients (AD) were timed as they performed a stepping accuracy test with increasing cognitive demand (Walking Trail-Making Test; W-TMT), which required stepping on instrumented targets with either increasing sequential numbers (W-TMT A) or alternating sequential numbers and letters (W-TMT B). RESULTS: After accounting for age and baseline walking speed, the AD and MCI+EF groups were significantly slower than the NC and MCI-EF groups on the task with the highest cognitive demand, W-TMT B (interaction effect F = 6.781, p <.0001). No group differences were noted on the W-TMT A task that was less cognitively demanding. Neuropsychological measures of executive functioning were associated with slower W-TMT B performance, whereas memory, visual attention and visual spatial skills were not (adjusted R(2) = 0.42). CONCLUSIONS: Executive function is important for stepping performance, particularly under more complex environmental conditions.
Authors: Manuel M Montero-Odasso; Yanina Sarquis-Adamson; Mark Speechley; Michael J Borrie; Vladimir C Hachinski; Jennie Wells; Patricia M Riccio; Marcelo Schapira; Ervin Sejdic; Richard M Camicioli; Robert Bartha; William E McIlroy; Susan Muir-Hunter Journal: JAMA Neurol Date: 2017-07-01 Impact factor: 18.302
Authors: Patrick J Sparto; Susan I Fuhrman; Mark S Redfern; Subashan Perera; J Richard Jennings; Alia A Alghwiri; Joseph M Furman Journal: Exp Brain Res Date: 2014-09-03 Impact factor: 1.972
Authors: Ellen L McGough; Valerie E Kelly; Rebecca G Logsdon; Susan M McCurry; Barbara B Cochrane; Joyce M Engel; Linda Teri Journal: Phys Ther Date: 2011-05-26
Authors: Jennifer G Lyons; Kristine E Ensrud; John T Schousboe; Charles E McCulloch; Brent C Taylor; Timothy C Heeren; Sherri O Stuver; Lisa Fredman Journal: J Am Geriatr Soc Date: 2016-11-22 Impact factor: 5.562
Authors: Sara L Wright; Rachel E Kay; Erich T Avery; Bruno Giordani; Neil B Alexander Journal: J Geriatr Psychiatry Neurol Date: 2011-06-24 Impact factor: 2.680