A delay in seeing a psychiatrist may affect illness
Older people with mental health problems may have to wait up to six months to see a psychiatrist in Northern Ireland.
The Alzheimer's Society said the government urgently needed to quantify how many people have dementia in Northern Ireland - so services can be designed to cope.
It is believed the long delay that some people face before seeing a psychiatrist may affect the course of their illness.
Charlotte Martin - who looks after her husband Peter at their home in Donaghadee, County Down, - said it was a difficult situation.
However, Charlotte is not alone - there are thousands of people like Peter.
One of the problems is that no one really knows how many similar cases there are.
'Lose cognitive function'
A report eight years ago recommended a review was carried out to establish the scale of dementia in Northern Ireland.
Dr Jim Anderson, a consultant psychiatrist, who works with older people said determining the scale was essential.
Alzheimer's Society said a fresh review was now needed
While dementia is an illness that primarily affects older people, younger people get it too.
Peter Martin was diagnosed around the age of 60. Like many people he is believed to have had the illness for a few years before that.
Charlotte said Alzheimer's had meant both she and Peter had lost out.
If someone notices a partner appearing to lose cognitive function, for instance, and their GP then refers them to a consultant, there are currently waiting lists of up to six months just to be seen.
Margery Magee of the Alzheimer's Society said patients were suffering.
The government report into dementia in Northern Ireland carried out in the mid-1990s made dozens of recommendations.
However, many have not been implemented.
The Alzheimer's Society said treatment has changed so much since that report that a fresh review is now needed.