The early dementia clue that strikes 20 years before first signs – as experts identify ‘stealth phase’

THE first sign of Alzheimer’s could appear decades before patients notice memory loss, scientists have revealed.

That’s because the disease, the most common type of dementia, develops in distinct phases – the first one being the ‘stealth’ phase.

GettyProblems with spacial awareness, such as struggling with a sat nav, could be one of the earliest warning signs, according to a study[/caption]

In a new study, spatial awareness issues, such as struggling with a sat nav or standing awkwardly close to people, were found to be the earliest warning signs – striking up to 20 years before traditional symptoms appeared.

Researchers from the Allen Institute for Brain Science in Seattle examined the post-mortem brains of 84 Alzheimer’s patients and uncovered evidence of early brain cell death long before damage was visible on scans.

They also found the disease two distinct phases, known as ‘epochs’.

The first phase, the ‘stealth’ phase, begins decades before symptoms become obvious and involves damage to just a few vulnerable cells in the brain.

This typically happens in the part of the brain important for navigation.

The second phase seeds a build up of tau and amyloid in the brain – proteins that are key players in the development of Alzheimer’s.

While most ageing brains contain some levels of these proteins, they can form plaques and tangle, which is thought to trigger more recognised dementia symptoms.

Telltale signs of cognitive collapse, such as memory loss, language difficulties, and problems thinking, start to appear.

The researchers used powerful machine learning software to track tau and amyloid.

They found even low levels caused damage to key brain cells known as inhibitory neurons.

Lead author Dr Mariano Gabitto, a neuroscience professor, explained: “Identifying the earliest neurons lost could be crucial for developing therapeutic interventions to protect them and prevent further cognitive decline.”

The researchers now want to determine whether this means they can accurately predict cognitive decline.

They’re confident early intervention during the ‘stealth’ phase could delay – or even prevent – the progression of the disease.

Dr Igor Camargo Fontana, director of scientific conference programming at Alzheimer’s Association, told Science Focus: “The disease’s long pre-symptomatic and silent period creates opportunities for early detection, early intervention and even prevention of dementia symptoms.”

In the UK, approximately 982,000 people are estimated to be living with dementia, including Alzheimer’s disease.

And the number of people living with dementia is projected to increase to 1.4 million by 2040.

GettyThe researchers believe early intervention during the ‘stealth’ phase could delay or prevent progression of the disease[/caption]

While there’s currently no cure for Alzheimer’s, spotting its symptoms is crucial because early diagnosis and treatment can help manage symptoms, slow the disease’s progression, and potentially qualify individuals for clinical trials.

One of the most common signs of Alzheimer’s disease, especially in the early stage, is forgetting recently learned information, according to the Alzheimer’s Association.

Others include forgetting important dates or events, asking the same questions over and over, and increasingly needing to reply on memory aids or family members for things they use to handle on their own.

Alongside spotting symptoms, it’s important to take proactive steps to maintain brain health. Follow the tips below…