The study, conducted by Oregon Health and Science University in the United States, found that slowing of the walking speeds in old age may be the early stages of dementia, known as mild cognitive impairment (MCI).
"In our study, we used a new technique that included installing infrared sensors in the ceilings of homes, a system designed to detect walking movement in hallways," study author Hiroko Dodge said.
"By using this new monitoring method, we were able to get a better idea of how even subtle changes in walking speed may correlate with the development of mild cognitive impairment (MCI, early stage of Dementia)," he added.
The study involved 93 people aged 70 or older who lived alone. Of those, 54 participants had no cognitive impairment, 31 had non-memory related MCI and eight had memory-related MCI.
They were given memory and thinking tests and had their walking speed monitored at their homes unobtrusively over a three-year period.
They were placed in groups of slow, moderate or fast based on their average weekly walking speed and how much their walking speed fluctuated at home.
The study found that people with non-memory related MCI were nine times more likely to be slow walkers than moderate or fast walkers and the amount of the fluctuation in walking speed was also associated with MCI, the Daily Mail reported.
"Further studies need to be done using larger groups of participants to determine whether walking speed and its fluctuations could be a predictor of future memory and thinking problems in the elderly," Dodge said.
"If we can detect dementia at its earliest phases, then we can work to maintain people's independence, provide treatments and ultimately develop ways to prevent the disease from developing. Our in-home monitoring approach has a lot of potential to be used for sustaining independence of the elderly," he said.
The research was published in the journal Neurology.