Drug treatment The Alzheimer's Society of Ireland has greeted with scepticism a new study which says drugs widely used to treat the disease have little actual benefit.
A five-year Lancet study by the University of Birmingham described the continual routine prescription of drugs used in the care of the condition as a 'waste of scarce resources'.
Ian McKeever of the Alzheimer's Society of Ireland told The Irish Times: "While the society does not advocate one drug over another, we certainly do acknowledge the crucial and integral role drugs play in the treatment of sufferers.
"It is known that drugs can halt the deterioration by up to 18 months, and one case in 10 actually see an improvement in their condition."
The society also said that the earlier drugs were administered, the greater the effects for patients.
"We strongly support early intervention with regards to drug prescription so people can get the most from their treatment. There is no doubt that drugs play a positive role in the mix of therapy given to patients," Mr McKeever said.
The study, which has prompted the British health service, the NHS, to investigate the matter, was carried out on 565 patients over five years.
The study also looked at the optimal dose and length of treatment, and what effect Donepezil has on the mood and behaviour of patients, their ability to undertake daily activities, and whether Donepezil relieved the burden on carers.
Lead researcher Prof Richard Gray said: "We've known for some time that patients do better on memory tests when they take these drugs but the improvements were small and we wanted to find out whether patients got benefits that really mattered to them - for example, could they go for a walk and find their way home.
"In particular, we wanted to know whether Donepezil delayed going into institutional care. If so, this alone would make the drugs worth paying for."
Donepezil did not seem to produce significant benefits for any of the criteria that the researchers examined. Patients taking the drug did do slightly better in memory tests - but the improvement was disappointingly small.
At present, there are 40,000 people suffering from dementia in Ireland and the drugs cost on average 1,500 per person every year.
Prof Gray said: "There are a lot of people with dementia and far too little money available to look after them. Doctors and healthcare funders need to question whether it would be better to invest in more doctors and nurses and better social support rather than routine prescription of these expensive drugs."
Prof Clive Ballard, director of research at the UK Alzheimer's Society, said he was disappointed by the findings, and concerned that they could be used to further restrict access to drugs which he believed could delay symptoms.
He said: "Over the past seven years, evidence from people with dementia and their carers has proved that cholinesterase inhibitors are effective, not as a cure for Alzheimer's, but for slowing the worsening of symptoms and improving quality of life for some people.
"It is extremely important that the results of this single trial do not lead to the withholding of important treatments for the many people with Alzheimer's disease who benefit from them."
Meanwhile, climbers on behalf of the Irish Alzheimer's society broke the world record last Friday for climbing the five highest peaks in Ireland and Britain.
They achieved their goal in a time of 16 hours and 16 minutes, 27 minutes quicker than the previous record, and also managed to raise 40,000 in the process.
Donations can be sent by texting PEAK to 57080 and 2 will go to the Alzheimer's Society of Ireland.