Motor slowing and cognitive slowing are more prevalent as we age. Importantly, the presence
of both in an older person increases their risk of having dementia by ten times. Currently,
there are no clinically meaningful predictors of progression to dementia in people with mild
cognitive impairment (MCI). The main hypothesis is that subtle variations in gait while
performing a simple cognitive task is a reliable, easy to perform, and feasible methodology
to detect those older adults at higher risk of progression to dementia and also, at higher
risk of further mobility decline and falls.
Rationale. The Canadian population is aging. According to recent estimates, the proportion of
the population aged 65 and older will increase rapidly from 13% in 2005 to 25% by 2031. This
increase in proportion is accompanied by a considerable amount of disability and subsequent
dependency which has major effects on both the quality of life of older adults and their
caregivers, and on the Canadian health care system. An important goal of geriatric medicine
is to reduce the gap between life expectancy and disability-free life expectancy by reducing
disability and dependency in the later years of life. A substantial portion of this
disability stems from two major geriatric syndromes: cognitive impairment and mobility
limitation. The ultimate manifestations of these syndromes are dementia and falls.
Interestingly, these manifestations often coexist in elderly people: falling is a common
geriatric syndrome affecting about a third of older adults each year, and dementia affects
about a third of Canadians aged 80 and over. Together, dementia and falls are responsible for
much of the discomfort, disability, and health care utilization in older adults and each will
become more prevalent as older Canadians are expected to number approximately $9 million by
2031. The combined direct cost of dementia and falls for the Canadian Health System is over
$4.9 billion per year.
Establishing reliable and easy to obtain predictors to accurately identify MCI patients at
highest risk of progressing to dementia is essential first, to determine who will benefit
from additional and/or invasive testing and second, to implement preventative strategies,
including cognitive training, physical exercises, and aggressive vascular risk factors
correction to delay progression. Even a modest one-year delay in dementia incidence could
save Canada $109 billion over 30 years.