A new national survey of nursing homes shows a significant under supply in the provision of specialist care for people with dementia in areas where demand will be significant in the future.

The survey also found that private nursing homes provide the bulk of specialist dementia care.

However, they do not receive any extra funding from the Government to help them comply with specific criteria laid down for this type of care.

The study was carried out by the Dementia Services Information and Development Centre (DSIDC) at Trinity College Dublin and St James's Hospital.

It was led by TCD Associate Professor Suzanne Cahill.

It surveyed 602 nursing homes and found 54 have dementia specific residential Special Care Units (SCUs).

1,034 people with dementia are resident in them, which represents 2% of the total number of people estimated to have dementia in Ireland.

The average number of people living in each SCU was 19, a figure far in excess of best practice recommendations.

The average number of residents in the Voluntary sector was 29, with 19 in the private sector and 16 in the Health Service Executive.

The research found some areas such as Cavan/Monaghan, Cork, Donegal and Galway are over-supplied with SCUs for dementia patients, while in others, including Dublin, Carlow and Wicklow, there is no provision.

But despite an expected increase in the prevalence of dementia in Ireland, no significant expansion in supply is likely in the foreseeable future, the researchers found.

The study found significant variation in the level of therapeutic activities on offer to patients in the SCUs.

Specific dementia specific training for staff was more common in private rather than HSE or voluntary SCUs.

Respite beds were in short supply with just 66 available across the 54 SCUs.

Based on the estimated 30,000 community-dwelling people with dementia in Ireland, this figure suggests one respite bed for every 450 people with dementia, the authors say.

The research was published at a Symposium on Dementia and Caregiving at Trinity College Dublin this morning.

It was addressed by leading US dementia expert Professor Steve Zarit, Professor of Human Development and Family Studies at Pennsylvania State University.

His "Zarit scale" is used in several different dementia care settings around Ireland to measure levels of stress experienced by family caregivers providing home care to their relatives diagnosed with dementia.

In a statement this evening the HSE said: "There are over 27,000 residential care beds, private & public, around the country [ratio 74:26, private:public beds].

"Of the 7,253 public bed capacity, 26% of the beds are short stay where people with dementia can receive rehabilitation, respite and convalescence and thereby keep them at home for longer.

"In the event of them requiring long stay residential care they may apply for funding support through the Nursing Home Support Scheme (Fair Deal).

"The HSE has rolled out a significant amount of dementia specific education to its staff based on the HSE 2010 Dementia Educational Needs Analysis and continues to do so.

"In 2012, the HSE funded the Alzheimer Society of Ireland €10.3m and the West of Ireland Alzheimer's Foundation just over €1m."