Disruptions in brain networks of older fallers are associated with subsequent cognitive decline: a 12-month prospective exploratory study.
Cognitive impairment and impaired mobility are major public health concerns. There is growing recognition that impaired mobility is an early biomarker of cognitive impairment and dementia. The neural basis for this association is currently unclear. We propose disrupted functional connectivity as a potential mechanism. In this 12-month prospective exploratory study, we compared functional connectivity of four brain networks- the default mode network (DMN), fronto-executive network (FEN), fronto-parietal network (FPN), and the primary motor sensory network (SMN)--between community-dwelling older adults with ≥ two falls in the last 12 months and their non-falling counterparts (≤ one fall in the last 12 months). Functional connectivity was examined both at rest and during a simple motor tapping task. Compared with non-fallers, fallers showed more connectivity between the DMN and FPN during right finger tapping (p  = 0.04), and significantly less functional connectivity between the SMN and FPN during rest (p ≤ 0.05). Less connectivity between the SMN and FPN during rest was significantly associated with greater decline in both cognitive function and mobility over the12-month period (r =  -0.32 and 0.33 respectively; p ≤ 0.04). Thus, a recent history of multiple falls among older adults without a diagnosis of dementia may indicate sub-clinical changes in brain function and increased risk for subsequent decline.
Aging, Mobility, and Cognitive Neuroscience Lab, University of British Columbia, Vancouver, British Columbia, Canada; Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada; Brain Research Center, University of British Columbia, Vancouver, British Columbia, Canada; Center for Hip Health and Mobility, Vancouver, British Columbia, Canada.
Chun Liang
CL
Hsu
Health, Brain, & Cognition Lab, University of Iowa, Iowa City, Iowa, United States of America; Department of Psychology, University of Iowa, Iowa City, Iowa, United States of America.
Michelle W
MW
Voss
Centre for Clinical Epidemiology and Evaluation, University of British Columbia & Vancouver Coastal Health Research Institute (VCHRI), Vancouver, British Columbia, Canada; Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada.
Todd C
TC
Handy
Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada; Brain Research Center, University of British Columbia, Vancouver, British Columbia, Canada; Centre for Clinical Epidemiology and Evaluation, University of British Columbia & Vancouver Coastal Health Research Institute (VCHRI), Vancouver, British Columbia, Canada.
Jennifer C
JC
Davis
Aging, Mobility, and Cognitive Neuroscience Lab, University of British Columbia, Vancouver, British Columbia, Canada; Brain Research Center, University of British Columbia, Vancouver, British Columbia, Canada; Center for Hip Health and Mobility, Vancouver, British Columbia, Canada; Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada.
Lindsay S
LS
Nagamatsu
Aging, Mobility, and Cognitive Neuroscience Lab, University of British Columbia, Vancouver, British Columbia, Canada; Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada; Brain Research Center, University of British Columbia, Vancouver, British Columbia, Canada; Center for Hip Health and Mobility, Vancouver, British Columbia, Canada.
Alison
A
Chan
Aging, Mobility, and Cognitive Neuroscience Lab, University of British Columbia, Vancouver, British Columbia, Canada; Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada; Brain Research Center, University of British Columbia, Vancouver, British Columbia, Canada; Center for Hip Health and Mobility, Vancouver, British Columbia, Canada.
Niousha
N
Bolandzadeh
Aging, Mobility, and Cognitive Neuroscience Lab, University of British Columbia, Vancouver, British Columbia, Canada; Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada; Brain Research Center, University of British Columbia, Vancouver, British Columbia, Canada; Center for Hip Health and Mobility, Vancouver, British Columbia, Canada.
Teresa
T
Liu-Ambrose
D000058:Accidental Falls; D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000503:physiopathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D011446:Prospective Studies