Brain connectivity differs dramatically between fallers, non-fallers

Brain connectivity differs dramatically between fallers, non-fallers

Findings from a recently published Vancouver Coastal Health Research Institute (VCHRI) study suggest that older adults who are experiencing multiple falls, even non-injurious ones, should report them to health care professionals as multiple falls may indicate subtle brain changes associated with cognitive decline.

Disruptions in brain networks of older fallers are associated with subsequent cognitive decline: A 12-month prospective exploratory study led by PhD student (Chun) Liang Hsu, researcher with the Djavad Mowafaghian Centre for Brain Health and the Centre for Hip Health and Mobility, was published recently in PLOS ONE. Hsu collected functional brain images from two groups of older adults: older adults who experienced two or more falls in the last 12 months (“fallers”) and older adults without a history of falls (“non-fallers”). The brain images were compared between the two groups to determine if there were differences in how well the brain coordinated various parts of itself — also known as functional connectivity.

“Functional connectivity of the brain is akin to how well different sections of an orchestra keep in time, tempo, and volume with each other to produce quality music,” explains Hsu. “We found several functional connections that were different in strength between older fallers and non-fallers. Importantly, the different functional connections observed in fallers were associated with subsequent decline in both physical and cognitive abilities.”

“While more research is needed to determine whether or not a recent history of multiple falls leads to cognitive decline, our novel findings do suggest that a history of multiple falls may be a biomarker of subclinical changes in brain functions and increased risk for subsequent decline in otherwise very healthy older adults,” says Hsu.

The results suggest that future screening efforts to identify individuals at risk for dementia or cognitive decline should include taking falls history. Early identification could lead to investigation and prevention strategies for those at high risk.

“Hsu’s work is the first to assess the neural signature of impaired mobility and how it is associated with subsequent decline in both physical and cognitive function,” says Hsu’s PhD supervisor, Dr. Teresa Liu-Ambrose, Canada Research Chair, and researcher at Djavad Mowafaghian Centre for Brain Health and the Centre for Hip Health and Mobility. “Cognitive impairment and dementia are both geriatric ‘giants’ and among the most pressing health care issues of the 21st century.”

Exercise boosts the body and the brain

One in three older adult falls every year and fall-related injuries are the leading cause of mortality among individuals 65 and older, however, exercise has been shown to reduce the risk of falls.

“Our own research has shown that exercise improves your physical function such as muscle strength and balance as well as your cognitive and brain function,” adds Dr. Liu-Ambrose, Research Director of the Vancouver General Hospital Falls Prevention Clinic and Director of the Aging, Mobility, and Cognitive Neuroscience Laboratory.

Hsu hopes to continue exploring the increasingly apparent link between exercise, mobility, and brain health in his future research.

“I’d like to conduct studies examining if and how different types of exercise training improve functional connectivity in older adults at particular risk for dementia, such as those with mild cognitive impairment, and whether improving certain functional connections will result in better cognitive and physical function,” Hsu says. “Such data will increase our understanding of how we can best promote functional independence among older adults through lifestyle interventions such as exercise.”