PhD student Vaisakh Puthusseryppady, from UEA’s Norwich Medical School, said: “We think this is because each road intersection represents a point at which a person needs to make a critical navigation decision.
“The more intersections there are, the more complex these intersections are, and the more disorganised the overall road network is – the bigger the problem for people with dementia.
“This is because these factors can make it more likely for people with dementia to make an error and make a wrong turn, causing them to get lost and go missing.”
Prof Michael Hornberger, from UEA’s Norwich Medical School, said there can be “life-threatening consequences” when people with dementia go missing.
He added he hopes the findings will help people predict which areas people with dementia may be most likely to go missing from, and help experts develop safeguarding measures to prevent them disappearing.
For example, carers may use routes with fewer intersections when planning for independent journeys, and recommend GPS tracking devices in complex networks.
And roads in neighbourhoods with a high number of older people could be designed to be more straight and ordered with simpler intersections.
Emma Bould, programme partnerships manager at the Alzheimer’s Society, said the research could tackle the problem of people going missing with dementia “in a radical way” by, “influencing town planning to build safe, secure and easy-to-navigate high streets and neighbourhoods”.
“Often what’s good for people with dementia is good for everybody,” she added.
“Having a road, or a layout, or a building which is easy to navigate, has clear lines of sight, is good for people who may be new to the area… (and) we’d call on more local authorities and town planners to make sure that they consider older people, when developing new developments.”