Blood tests for Alzheimer’s could be available on the NHS within five years, experts have said, following the launch of a £5 million project which aims to speed up diagnosis.

At present, diagnosing Alzheimer’s – the most common form of dementia – relies on brain imaging or painful lumbar punctures, where a sample of cerebrospinal fluid is drawn from the lower back.

Less than two-thirds of people in England with dementia have a formal diagnosis and many can face long waits to be seen.

Alzheimer’s Research UK and the Alzheimer’s Society are working with the National Institute for Health and Care Research (NIHR) to make blood tests on the NHS a reality and reach more people.

"We expect more people to be coming forward for diagnosis, we expect them to be coming forward at a younger age and we expect them to be coming forward with less obvious symptoms," said Dr Susan Kohlhaas, executive director of research and partnerships at Alzheimer’s Research UK.

Many people know that Alzheimer’s – which is caused by the build-up of substances in the brain called amyloid and tau – can cause cognitive issues.

"Everyone’s different, but the most common symptoms for someone with Alzheimer’s are problems with forming new memories," says Tim Beanland, head of knowledge and learning at the Alzheimer’s Society and author of Mind Games.

"If you’ve got someone with Alzheimer’s-type dementia often you might tell them something and then five minutes later they’ll ask you the same question, because they haven’t remembered what you’ve told them."

But what are the less obvious symptoms? We asked experts to talk through the early warning signs of the condition.

Vision problems

"If somebody has young-onset Alzheimer’s they can present with memory problems, but they’re more likely to have what we call atypical symptoms," says Beanland.

"There’s a form that affects the back of the brain where vision is processed, and in that, people will have problems with reading or three-dimensional perception.

"They often go to the optician and think they have problems with their eyes, but actually their eyes are fine, it’s the brain that’s processing things wrongly."

Speech and language

"Speech and language can also demonstrate early symptoms, such as not being able to find the right word or using substitutes for words such as ‘the thing you write with’ instead of pen," says Dr Emer MacSweeney, CEO and consultant neuroradiologist at Re:Cognition Health

"Losing your train of thought, loss of verbal fluency and experiencing communication problems can also be indicators."

Behaviour and mood

In what’s called frontal variant Alzheimer’s, which affects the front of the brain, mood or personality changes may occur.

"The front of the brain is responsible for behavioural regulation and our motivation so somebody with frontal variance Alzheimer’s will often have behavioural changes," Beanland suggests.

"They might be obsessive or they might lose emotional regulation. They might be very blunt in their relationships with people. So you’ll see a personality change, which is not what you normally see in somebody with typical dementia."

What should you do if you spot these signs?

"In Alzheimer’s people often lose insight and they think they’re fine," Beanland says, which is why it’s more likely friends or family members will spot the early warning signs.

Either way, it’s important to go to your GP in the first instance, he advises, particularly for younger people: "Dementia is not that common and so if you have some of these symptoms, they might be something else.

"For example, some of the behavioural changes might be caused by relationship problems, stress at work or menopause."

Early detection is key to ensuring the optimal outcome for those who are diagnosed.

"While symptoms may stem from treatable causes, early detection of Alzheimer’s offers opportunities for proactive intervention," MacSweeney says.

"The ongoing advancements in Alzheimer’s research, particularly the development of new-generation medications, emphasise the importance of early access for maximum benefit in slowing or halting the progression of the disease and its symptoms."

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