More than 2,000 intellectually disabled people are without any service or a major element of a service, according to new official figures.
The numbers, contained in the National Intellectual Disability Database report for 2004, show almost 1,900 full-time residential places are needed for this group within the next four years, along with 347 day programmes and more than 1,700 residential support services.
The figures come just ahead of today's Budget, which is expected to provide a special package of measures for the disability sector. It will include funding for 270 new residential places, 90 new respite places and 400 new day places.
The report's co-author, Ms Fiona Mulvaney, said while new day places were welcome, planned increases in residential places would fall well short of meeting the needs of intellectually disabled people.
"If the demand for residential services continues to rise at the rate observed over the past two years, only a small proportion of the existing and emerging need in this area will be addressed," said Ms Mulvaney of the Health Research Board.
The strong demand for residential places is likely to continue in the coming years because the number of people over 35 years of age diagnosed with a severe intellectual disability has increased by almost 20 per cent over the last 30 years.
The majority of intellectually disabled children and adults live at home with parents or siblings. However, the number of intellectually disabled people living longer is increasing and more are requiring residential care as they tend to outlive their carers.
The report's other co-author, Mr Steve Barron, said: "This will have serious implications for support services for ageing carers and services designed to meet the needs of older people with intellectual disability in the next few years."
Despite significant investment in intellectual disability services in recent years, these demographic factors led to a 14 per cent increase in the number of people requiring residential services over the last two years. The report also recorded substantial progress in the sector since the first official report in 1996.
There has been a 55 per cent reduction in the number of people with intellectual disabilities accommodated in psychiatric hospitals over the last eight years, while there has been a 45 per cent growth in numbers living full-time in group homes within local communities.
Residential support services, in particular planned or emergency-based respite services, have grown by 357 per cent.
The report also identified 11,416 intellectually-disabled people who are receiving services but will require alternative or additional services within the next five years.
