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Each year in Japan thousands of elderly people with dementia go missing, hundreds are never found alive again.
Japan has the world’s oldest population but also some of the most advanced technology and they’re using it to help keep people with dementia safe.
People like Mrs Itou who lives in the city of Matsudo.
The first time she went missing her son who cares for her went driving around looking for her in the places she normally goes.
That was no easy task as Mrs Itou loves to walk and can cover a hundred kilometres a month.
That time his mother came home ... Read even more
