It is difficult to quantify the exact cost of dementia, given the many different individual costs and the fact that many people do not have a formal diagnosis.

However, it is clear that there are very significant economic implications in terms of direct medical and social costs, as well as the costs of informal care.

In 2010, the total global societal cost of dementia was estimated by the World Health Organisation to be $604 billion (€444 billion). This corresponds to 1 per cent of the worldwide gross domestic product (GDP), or 0.6 per cent if only direct costs are considered.

In Ireland, the 2012 Creating Excellence in Dementia Care: A Research Review for Ireland's National Dementia Strategy report by the Department of Health and Children estimated the overall cost of dementia in Ireland to be just over €1.69 billion a year, and said this figure increased significantly over the previous decade.

At 48 per cent, almost half of this cost is attributable to informal care provided by family and friends to people with dementia living in the community.

A further 43 per cent is accounted for by residential long-stay care, while formal health and social care provision, linked mainly to primary and community care, comprises only 9 per cent of the total cost of dementia.

Giving a further breakdown of the total cost, the report shows that combined formal health and social care costs came to €148 million in 2010.

Of this figure, primary and community care accounted for 44 per cent; psychiatric care accounted for 26 per cent; and acute-hospital care accounted for 14 per cent of this cost. Primary and community care for those with dementia was €65 million, of which 59 per cent was spent on respite care.

In relation to medicine costs, approximately 75 per cent of people with dementia living in the community are prescribed an antidementia drug, with a significantly smaller proportion receiving antidepressant, antianxiety, or antipsychosis drugs.

In 2010, the total cost associated with dementia-related medication was almost €16 million, of which 85 per cent was spent on antidementia drugs.

Community care

Improving care in the community and providing greater support for families will require additional public spending, including having to make difficult choices about the reallocation of some of the existing institutional resources to community care, given the perilous state of the public finances, the report notes.

Furthermore, as the numbers with dementia rise nationally and internationally, serious concern is being raised that many countries will simply not be able to cope with the growing cost of dementia.

Ireland is predicted to have the largest growth in the older population of all European countries in the coming decades, according to a paper by health economist Dominic Trepel of the University of Limerick.

According to Trepel, the “economic burden of dementia ranks higher than stroke, heart disease and cancer combined; however, healthcare allocations for dementia continue to be substantially lower than each of these individual disease groups”.

The HSE's Social Care Division is strategically realigning the model of care for older people to help them maintain their dignity and independence so they can stay in their own homes and communities for as long as possible, a HSE spokesperson told The Irish Times.

Central to this model of care is the provision of intensive home-care packages. In 2014, through the realignment of long-stay funding, and through funding for Section 39 agencies (about €110 million a year), a wide range of services, from small social satellite services, daycare centres and meals on wheels, to home help and home-care packages were provided to people with dementia.

In 2013, the HSE funded the Alzheimer Society of Ireland €10.1 million and the West of Ireland Alzheimer’s Foundation about €1.6 million.

There are more than 27,000 residential care beds, private and public, around the State.

Of the 7,253 public bed capacity, 26 per cent are short stay, where people with dementia can receive rehabilitation, respite and convalescence that enables them to stay at home for longer.

If they require long-stay residential care, they may apply for funding support through the Nursing Home Support Scheme (Fair Deal), though the HSE does not say how much dementia patients receive from Fair Deal.

Specialist services

As dementia is predominantly a disease of older life, the HSE specialist services provided include consultant geriatricians, consultant psychiatry of old age and their relevant multidisciplinary teams.

There are 89 approved posts for consultant physicians in geriatric medicine in the HSE.

Given the enormous and growing costs of dementia, it is not surprising that the scientific community is working to develop medicines that can prevent, stop or significantly slow its progress.

The G8 Summit on Dementia, which was held in the UK in December 2013, pledged to develop a cure or treatment for Alzheimer's by 2025.

At the summit, the British prime minister, David Cameron, said his government would more than double its annual research funding to £132 million (€166.2 million) by 2025.

He called on the world’s governments, industries and charities to commit more funding to finding a cure for dementia.