“Finding early dementia detection methods is vital. In the future, it is conceivable that we will be able to diagnose Alzheimer’s disease and other dementias before people even have significant memory loss. My team and I believe that gait, as a complex brain-motor task, provides a golden window of opportunity to see brain function that researchers should take advantage of. The high variability seen in people with cognitive impairment can be regarded as a “gait arrhythmia,” which has been proven to predict mobility decline and falls, and now, further cognitive impairment and progression to dementia.” Dr. Manuel Montero-Odasso
According to the Alzheimer Society of Canada, more than 500,000 Canadians are living with Alzheimer’s disease or a related dementia. In 15 years, this number is expected to rise to 1 million. Annually, Canadians spend more than $10 billion to care for those living with dementia.
Currently, there is no definitive way for health care professionals to predict the onset of dementia in patients who have mild cognitive impairment (MCI). However, geriatrician and researcher – Dr. Manuel Montero-Odasso – shows that there may be a glimmer of hope in the near future.
Montero-Odasso leads a research team at the Gait and Brain Lab (London, ON) with a focus on walking speed and walking variability. These features of a person’s walk, he explains, can help to indicate changes in the brain and may thereby serve as a predictor of the progression of MCI to dementia. Confirming this theory and responding to MCI early with targeted interventions could help to delay its progression to dementia.
Although walking has long been considered an automatic motor task, emerging evidence suggests that cognitive function plays a key role in one’s ability to control his or her movement, including avoiding obstacles and maintaining navigation.
During research visits to his lab, Montero-Odasso’s research staff ask people with MCI to walk on a specially-designed mat that is connected to a computer. The computer records the individual’s walking gait variability and speed. This information is then compared to their walking gait while simultaneously performing a cognitively demanding task, such as counting backwards or doing calculations while walking, i.e. “walking-while-talking”.
Their research has demonstrated that specific gait characteristics are associated with high variability, particularly during “walking-while-talking” exercises. These gait abnormalities are more apparent and pronounced in individuals who have episodic memory challenges (i.e. memory of autobiographical events) and executive dysfunction. Taken together, this reveals a “motor signature” of cognitive impairment, Montero-Odasso explains. Importantly, Montero-Odasso and his team found that older adults with MCI who have to slow down their usual way of walking by more than 20% when they add a cognitive task are at a 7-times increased risk of developing Alzheimer’s disease within a 5-year time frame.
To confirm this research, Montero-Odasso’s team awaits data from the Canadian Consortium on Neurodegeneration in Aging (CCNA). The CCNA provides the infrastructure and support that facilitates collaboration amongst Canada’s top dementia researchers. By the end of 2018, 1650 Canadians between the ages of 60 and 85 who are living with, or are at risk of developing, dementia will be enrolled in 30 sites across Canada. Where available, CCNA research participants utilize an electronic gait walkway for their gait assessments. The major goals of the CCNA’s signature study are to:
- Learn about who is at risk of developing dementia
- Determine how early dementia can be detected
- Find out what tests are most effective at detecting dementia
If Montero-Odasso’s research is confirmed using CCNA data, then “walking-while-talking” gait changes may indeed be an effective predictor of cognitive decline and progression to dementia, and may eventually help with an earlier diagnosis of dementia, or to detect the subgroup of patients who are at risk and could most benefit from invasive diagnostic procedures or early interventions.
The views and opinions expressed in this guest blog are those of the authors (individual CCNA scientists) and do not necessarily reflect the views of the Canadian Consortium on Neurodegeneration in Aging and its partner organizations.