Regular eye tests could in future be used to diagnose early-stage Alzheimer's, new research suggests.
Early trials of two different techniques show that a key Alzheimer's biomarker can be identified in the retina and lens of the eye.
Both methods were able to distinguish between probable Alzheimer's patients and healthy volunteers with a high level of accuracy.
Although the research is still at an early stage, further work could see such tests used as a first step in identifying individuals with Alzheimer's. Early diagnosis of Alzheimer's is essential to developing effective treatments that do more than alleviate the condition's symptoms.
A new blood test based on 10 "biomarker" proteins will make it possible to test new treatments at an early stage of Alzheimer's progression.
Writing in the journal Alzheimer's & Dementia, researchers from King's College London describe how they investigated 26 proteins previously associated with Alzheimer's disease.
They analysed blood samples from 476 confirmed Alzheimer's patients, 220 individuals with "mild cognitive impairment" (MCI) who experienced occasional memory loss, and 450 healthy elderly people.
In the vast majority of cases, memory lapses do not lead to Alzheimer's. But the researchers identified 10 blood proteins that appeared in 87% of MCI patients diagnosed with the disease within a year.
A blood test that can predict the onset of Alzheimer's disease before recognisable symptoms appear could become available in two years, scientists have said.
The test, likely to cost £100 - £300, can show with almost 90% accuracy which individuals suffering from mild memory loss are going to develop Alzheimer's within a year, researchers suggest.
Trials of drugs to halt or reverse Alzheimer's have all ended in failure so far. Therapies exist that can reduce its symptoms, but they only work for a short period of time and are not very effective.
Scientists believe a major reason for the lack of progress is that trial patients are being recruited too late, when their disease is already far advanced.
Dr Doug Brown, the Alzheimer's Society director of research and development, said people "must be given a choice about whether they would want to know, and fully understand the implications" of a test that could predict the onset of the disease.
We asked users of the ITV News Facebook page whether they would want to know in advance if they were likely to develop Alzheimer's.
- Dawn Kinsley: "One of the worst diseases going. So I would want to know, then I can get together my 'care' plan, have some 'careless' good times while I still remember and can enjoy."
- Mechelle Thomson: "Only to prepare my family so they would know what to expect. A little education could go a long way."
- Michael King: "How depressing knowing that you're going to get it in advance and being able to do little about it. I'd rather not know."
Scientists have developed a new blood test that could detect whether a person will develop dementia within three years.
By looking at 10 specific blood molecules, researchers from America's Georgetown University were able to test whether people would go on to develop cognitive impairment or Alzheimer's Disease - with 90% accuracy.
ITV News spoke to Dr Alison Cook from the Alzheimer's Society:
The study monitored 525 healthy over-70s for five years. During the research, 28 participants went on to develop the conditions. 46 were diagnosed at the start of the study.
A blood test that could predict the onset of Alzheimer's poses ethical challenges, an expert from the Alzheimer's Society has said.
A new study published in the journal Nature Medicine found that changes in the blood may predict whether someone will develop Alzheimer's.
"Having such a test would be an interesting development, but it also throws up ethical considerations," Dr Doug Brown, the charity's director of research and development, said.
"If this does develop in the future people must be given a choice about whether they would want to know, and fully understand the implications.
Dr Brown said there needed to be larger studies with different populations before it could be turned into a blood test for Alzheimer's disease.
A breakthrough in the quest to find a blood test for Alzheimer's will help doctors and patients "manage the disease", one of the researchers has said.
Professor Howard Federoff explained:
Our novel blood test offers the potential to identify people at risk for progressive cognitive decline and can change how patients, their families and treating physicians plan for and manage the disorder.
The preclinical state of the disease offers a window of opportunity for timely disease-modifying intervention.
Biomarkers such as ours that define this asymptomatic period are critical for successful development and application of these therapeutics.
We consider our results a major step toward the commercialisation of a preclinical disease biomarker test.
Scientists have developed a new blood test which could be used to detect early symptoms of Alzheimer's disease and whether a healthy person will develop the disease within the next three years.
Scientists believe changes in the blood are an indicator of the degenerative disease in its earliest stages.
A new study, published in the journal Nature Medicine, identified 10 molecules in blood could be used to predict with at least 90% accuracy whether people will go on to develop mild cognitive impairment or Alzheimer's disease.
Researchers from Georgetown University Medical Centre in the US examined 525 healthy participants aged 70 and over and monitored them for five years.
During the research 28 participants went on to develop the conditions and 46 were diagnosed at the start of the study.
Actor Timothy West told how his wife Prunella Scales has "a sort of mild Alzheimer's" in a new documentary.Read the full story ›
A dementia sufferer's son said the disease "strips someone of their character", as Jeremy Hunt called on Britain to "raise our game" on the illness.
Pauline Murray-White's son filmed his mother's battle with the illness since she was first diagnosed in 2007 and captured the moment she struggled to recognise a picture of her late partner.
James Murray-White said the relationships of sufferers "eventually shatter."
He added: "Dementia just strips someone of their character, their personality, who they and what they knew."