Tracking dementia patients would help them lead healthy and independent lives, according to the manager of a specialist nursing home in Oxford.

Patricia O'Leary, of Vale House, in West Way, Botley, has welcomed the Alzheimer's Society's view that people with brain disorders should be given the option of wearing an electronic tag so they can roam freely outside their own homes.

Many people with dementia feel compelled to walk about - a symptom often described as wandering - but 40 per cent of those with the condition have become lost at some time, leaving them vulnerable and unsafe, and their loved ones and carers distressed.

The society wants patients to have more access to tracking devices, which would use satellite navigation technology to locate them.

Mrs O'Leary said: "If someone is fit and able, despite their awful brain disorder, walking is an important form of exercise, and letting them go out is better than them not being allowed out of their own homes at all.

"Anything that helps them stay at home and stay independent for longer is a good idea. If people are able to move around freely, it's a good way to get exercise and fresh air. People with dementia aren't going to die for a long time, so keeping them fit is vital."

Tagging systems would also provide reassurance for carers. Mrs O'Leary added: "Anything that promises peace of mind for families and carers of people with dementia is worthwhile."

Colin Smith, 76, of Oxford, cares for his wife Maria, 79, who has Alzheimer's. Four years ago, the Smiths joined a tracking trial, where the device was the size of a video cassette.

He said: "When my wife first wandered, we were in London and I spent the night sitting in a police station waiting for her.

"If I could have had any way of finding her, then it would have been hugely valuable. It's important to have devices which are practical and small enough to have on you all the time."

For more information, see www.alzheimers.org.uk/talkingpoint or call the national helpline on 0845 300 0336.