ONE in 10 care homes for the elderly provides specialist care for people with dementia but, according to official figures, up to 90% of residents may have the illness.

The newly revealed statistics expose a care gap, which experts say cannot be addressed without more and better trained staff.

Scotland's Care Inspectorate has revealed that of 1284 care homes for adults, 908 of which are specifically for older people, just 106 claim to be specialists in dementia care.

The Church of Scotland's social care charity, Crossreach, said the incidence of dementia in its care homes is "huge", affecting more than 70% of all residents.

Meanwhile, a study carried out in Glasgow for the Scottish Government in 2012 concluded that dementia in mainstream care homes was under-diagnosed by up to 32%, meaning 90% of residents either had a dementia diagnosis or showed signs of symptoms.

The research, published in the International Journal of Geriatric Psychiatry, which surveyed one in six residents of Glasgow care homes, found 234 residents already had a diagnosis of dementia, but only 134 were in specialist dementia beds.

Meanwhile, a further 138 residents without a diagnosis showed symptoms consistent with dementia.

Professor June Andrews, director of the Dementia Services Development Centre at the University of Stirling, said there was no reason that such findings could not be replicated across the country.

She said the time had come to recognise that all homes needed to be staffed and designed to cope with dementia. "You don't get in to most care homes unless you have dementia or are very frail, so a care home these days is a dementia hospice, therefore every care home should be designed to compensate for the needs of people with dementia," she said.

"They are likely to be the majority, and staff should be able to cope with disturbing behaviour and other special needs of people with dementia."

Crossreach has developed a specialism in residential provision and other services for adults with dementia and runs eight homes providing 24-hour care for dementia sufferers.

Allan Logan, director of older people's services at the charity, said it had recently increased staffing and converted two homes to specialise in dementia in recognition of the increased need.

He added: "There's a huge incidence: at least 70% of those in our care homes have dementia."

The charity also has 47 dementia ambassadors who work to develop knowledge of the condition in its traditional residential homes, and all staff are being trained in understanding dementia, he said.

Crossreach estimates that the ratio of staff to residents needs to be 30%-40% higher in care homes that specialise in dementia but, while some councils recognise this, others are not prepared to fund the additional cost.

Ranald Mair, director of Scottish Care, which represents the private care industry, said a national contract with local authorities had not recognised the need for specialist dementia care nor the expense of higher staffing and better training.

He said that while Glasgow and Edinburgh had several homes offering specialist provision other areas are less well off.

He added: "For smaller authorities the numbers may not justify a whole specialist home. Glasgow at least has some dedicated provision but in parts of the country people may struggle to access specialist care.

"The danger is we go on just trying to provide a bog-standard level of care to every elderly person.

"Some homes cater for dementia very well even though they don't specialise, but it is hard to maintain specialist provision without adequate levels of funding."

The Scottish Care Inspectorate figures are the most recent available and date from December 2012.

Last week, it was reported the Care Inspectorate has uncovered a wide range of practice, good and bad, across the care sector during its unannounced visits.