People with dementia have a higher risk of getting lost in areas with dense and complicated road networks, research suggests.
Experts studied three years of “missing person” police reports for people with dementia to see if there was a link to the outdoor environment they went missing from.
The study was led by the University of East Anglia (UEA) with University College London, the University of Leeds, the Norfolk and Norwich University Hospital, and Norfolk Constabulary.
Researchers looked at 210 police records of people with dementia going missing in Norfolk between January 2014 to December 2017 – comparing each case to the nearby road network.
Previous research has suggested around 70% of people with dementia may go missing at least once, with some at risk of going missing multiple times.
Prof Michael Hornberger, from UEA’s Norwich Medical School, said there can be “life-threatening consequences”, adding: “Around 40,000 people with dementia go missing for the first time every year in the UK – and this figure is likely to grow with the projected increase in the dementia population.
“Unfortunately, the first event when people with dementia go missing comes completely out of the blue, when doing such routine activities as going for a walk with the dog or getting the newspaper from the local shop.”
People with dementia can have difficulty with navigating, so the researchers looked at the impact of the complexity of road networks, intersections and overall organisation.
They found that the higher the density of intersections, the more complicated they were and the less grid-like the overall layout, the greater the risk for dementia sufferers to get lost.
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.”
He said 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.
The paper is published in the journal Scientific Reports.
Emma Bould, programme partnerships manager at the Alzheimer’s Society, said: “Because dementia often impacts memory and orientation people with the condition are more likely to get lost, even in places they know well.
“This research could tackle the problem in a radical way by influencing town planning to build safe, secure and easy-to-navigate high streets and neighbourhoods.
“It’s really important everyone with dementia can stay independent for as long as possible, so we advise people with dementia and their carers to carry identification, or details of someone who can be contacted, if they get lost.
“And for family members concerned about a loved one going missing, we recommend filling out the Herbert Protocol at your local police station – a simple form designed to make sure that the police can get access to important information about a missing person as quickly as possible.”