Smiling senior couple taking a walk in nature and talking to each other.

Slowing down may seem the privilege of the elderly but pensioners who take it too easy may be at risk of Alzheimer’s disease, a study has suggested. Older people who walk slowly could be suffering from a build-up of the sticky amyloid brain plaques, which lead to dementia.

A study of 128 people in their seventies with memory problems found that amyloid level accounted for up to nine per cent of the difference in walking speed. The average speed of those taking part was 3.7km/h, but pensioners who walked more slowly had higher concentration of amyloid. Researchers said lifestyle factors such as smoking and lack of exercise have been known to both hinder walking and raise the risk of dementia. But they say it is possible that a slow gait speed may also signal changes in the body that could make Alzheimer’s more likely.

“It’s possible that having subtle walking disturbances in addition to memory concerns may signal Alzheimer’s disease, even before people show any clinical symptoms,” said study author Dr Natalia del Campo, of the Gerontopole and the Centre of Excellence in Neurodegeneration of Toulouse in France.

To find out the link between walking speed and Alzheimer’s, scientists scanned the brains of participants to find out how much amyloid was present and tested them on thinking and memory skills and how well they could complete everyday activities. The researchers found an association between slow walking speed and amyloid in several areas of the brain. Charities said that a change in mobility was often associated with Alzheimer’s.

Dr Laura Phipps from Alzheimer’s Research UK, said: “While forgetfulness and confusion are usually the first symptoms that people associate with Alzheimer’s disease, there can also be a range of physical symptoms, such as mobility problems.

“It will be important to follow more people over a longer period of time to look at changes in walking pace to better understand whether slower movement could be a consequence of Alzheimer’s, or an independent event driven by other shared risk factors.

“There can be many reasons for someone’s walking speed to slow, but it’s important to explore why and when these changes occur.” The research was published in the online journal Neurology.