G8 health ministers have met in London to tackle what experts warn is a dementia time-bomb, with cases set to soar as the world's population ages.
Ministers from the Group of Eight wealthy nations gathered for their first-ever conference on the incurable condition, which afflicts some 44 million people worldwide.
Alzheimer's Disease International has warned that the number of sufferers is expected to treble to 135 million by 2050, as life expectancy rises around the globe.
According to the World Health Organization, dealing with dementia cost the world an estimated $US604 billion ($A665 billion) in 2010.
Ahead of the conference, British Prime Minister David Cameron called for a worldwide boost in research investment, with Britain set to double its funding to STG122 million ($A221 million) by 2022.
Cameron is seeking similar pledges from fellow G8 nations Canada, France, Germany, Italy, Japan, Russia and the US, and from pharmaceutical companies and charities attending the summit.
University experts, patient networks and representatives from BT, Intel, Nike and GE Healthcare took part in the panel discussions alongside ministers.
In a video shown to the conference, Hilary, who married her husband Peter five years ago and was diagnosed with Alzheimer's in 2012, said she would not have married if she'd known about her condition.
"You realise what it's going to do to your partner... I just wouldn't want to put anybody through that."
British health minister Jeremy Hunt urged colleagues to redouble efforts to find drugs that can halt or reverse brain decay, to improve diagnosis rates and combat the stigma around dementia.
"As life expectancy goes up, our generation has a unique challenge: will those extra years at the end of our lives be ones we can look forward to with anticipation - or will they be ones we end up dreading?" Hunt said.
