The number of people living with dementia around the world is now estimated at 44 million, or up 22% from three years ago, according to a report released today by Alzheimer’s Disease International (ADI), a federation of Alzheimer’s associations around the world.
The increase on the ADI’s previous finding is due at least in part to improved reporting of dementia prevalence in China and sub-Saharan Africa. And as people live longer, cases of dementia — a catch-all term describing the loss of memory, mental agility and understanding owing to neurodegenerative diseases such as Alzheimer’s — will rise to 76 million by 2030 and to 136 million by 2050, the ADI report says. “The current burden and future impact of the dementia epidemic has been underestimated,” it concludes.
The report ratchets up the pressure on funders to invest more into tackling dementia ahead of an 11 December summit in London, at which the World Health Organization and ministers from the G8 (Group of Eight) countries will discuss a global action plan on the condition.
“This is a once-in-a-generation opportunity to turn the tide on dementia,” Doug Brown, director of research and development at the Alzheimer’s Society, a charity based in London, told reporters at a briefing yesterday. “We need as much investment in dementia research as we have in cancer,” he said.
Indeed, despite well-publicized political commitments — the United Kingdom’s prime minister David Cameron launched a ‘dementia challenge’ in March 2012, and the US government set out plans for extra Alzheimer’s funding in May 2012 — levels of funding remain low.
In the United Kingdom, for example, dementia costs the economy £23 billion a year (though mostly not in front-line medical expenses), the Alzheimer’s Society estimates — which is twice the burden of cancer. But public research funding only amounts to some £60 million a year, and that is barely one-eighth of what is spent on cancer research. The problem is similar around the world, Brown says.
Nick Fox, a neurologist who heads the Dementia Research Centre at University College London, says, more conservatively, that he hopes the G8 will double dementia funding in the next five years.
Drugs designed to fight Alzheimer’s disease have proved disappointing in clinical trials so far. But, says Fox, “some of the trials have been like trying chemotherapy for cancer when the patient is already in a care hospice,” given that Alzheimer’s starts to attack the brain up to a decade before symptoms such as memory loss appear.
In a new approach, at least four clinical trials are now planning to treat people who have not yet developed Alzheimer’s symptoms. One is a five-year trial of an antibody, crenezumab, which binds to fragments of neuron-damaging amyloid-β. The drug will be tested in people who carry a rare genetic mutation that makes them certain to get the disease. Another, the Dominantly Inherited Alzheimer’s Network study, will enrol patients with a possible familial risk for Alzheimer’s; a third, by companies Takeda (based in Osaka, Japan) and Zinfandel Pharmaceuticals (based on Durham, North Carolina), hopes to test an experimental drug in people whose genetic makeup suggests elevated risk of Alzheimer’s; and a fourth, known as the A4 study, will treat people who show biomarker evidence of amyloid plaques in positron-emission tomography.
The ADI report adds that better care and timely diagnoses are important, too. And dementia is not just a disease of the well-off: though cases are concentrated in the richest and most demographically aged countries, 63% of people with dementia live in low- and middle-income countries where there is limited access to social services and support.
