British writer Sir Terry Pratchett has called for greater investment in dementia research to deal with the "worldwide tsunami" of dementia.
The science-fiction author himself is suffering from a rare form of Alzheimer's disease, and he donated last year $1m for research into Alzheimer's disease.
His call for more funding comes after experts predicted the number of people with dementia will almost double every 20 years across the world.
The fact people are living longer than ever before is a major factor driving the increasing incidence of dementia.
Sir Terry said: "We are facing - to use the term said to me by one of the leading US researchers - a worldwide tsunami of Alzheimer's and other dementia diseases.
"Technically I am early onset, but growing older behind me are the baby boomers, made strong and fit as the first generation to grow up in the beneficent arms of the National Health Service.
"Is there going to be a government of any stripe willing to put its money where its mouth is and fund changes? Or will dementia remain the most feared disease of the over-55s?"
Experts at King's College London yesterday estimated that the number of people with Alzheimer's will reach 65.7 million in 2030 and 115.4 million in 2050.
A total of 35.6 million people will have dementia in 2010, the report said.
It is thought that 37,000 people in Wales and their carers are affected by Alzheimer's or other forms of dementia.
Marc Wortmann, executive director of Alzheimer's Disease International, which published the predictions, said: "The crisis of dementia and Alzheimer's can no longer be ignored. Unchecked, Alzheimer's will impose enormous burdens on individuals, families, health-care infrastructures, and the global economy."
Professor Julie Williams, the Cardiff University-based chief scientific adviser to the Alzheimer's Research Trust, led the team which found two genes linked to Alzheimer's disease.
She said: "Week after week British dementia scientists come a step closer to understanding what causes dementia, and how this might be translated into new treatments. Despite the current squeeze in public finances, upping our investment in dementia research would be prudent.
"If we can work out how to delay the onset of dementia by five years, we could halve the number of people who die with the condition."
Professor Martin Prince, from the Institute of Psychiatry at King's College London, who led the research, said: "While these numbers are staggering, the current investment in research, treatment and care is actually quite disproportionate to the overall impact of the disease on people with dementia, their carers, on health and social care systems, and on society."
Neil Hunt, chief executive of the Alzheimer's Society, added: "It is essential politicians lead the way in devising a co-ordinated plan and commit to more investment into dementia research if we are to stand any chance of defeating this devastating disease.
"Terry's views are supported by the public. It is clear we must act now."