Disclaimer: The information in this article is for general informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. We encourage you to seek expert guidance before making any medical decisions.
Dementia is a word that strikes fear into the hearts of many Australians, especially as we get older. But what if the first signs of this memory-robbing disease could appear decades before the classic symptoms we all know—like memory loss and confusion—set in?
Recent research suggests that dementia, particularly Alzheimer’s disease, may have a ‘stealth phase’ that can begin up to 20 years before diagnosis, and the earliest warning signs might be much subtler than you think.
For years, dementia diagnosis has relied on memory tests and brain scans, looking for the telltale shrinkage or protein build-up that signals the disease is well underway.
However, scientists from the Allen Institute for Brain Science in Seattle have discovered that dementia develops in two distinct phases, or ‘epochs’.
The first, dubbed the ‘stealth phase’, is a silent, slow-moving process. Only a handful of vulnerable brain cells are damaged during this time, long before any significant changes appear on an MRI (Magnetic Resonance Imaging) or before you forget names and appointments.
According to Professor Michael Hornberger, a dementia expert from the University of East Anglia, this early damage often occurs in the part of the brain responsible for spatial navigation.
So, what does this mean for you? The first sign of dementia might not be forgetting your keys or struggling to recall a friend’s name. Instead, it could be something as subtle as getting lost in a familiar place, having trouble reading a map, or even standing too close to others in a queue.
These issues with spatial awareness can be easy to dismiss as ‘just getting older’ or being a bit distracted, but they may be the brain’s first cry for help.
Hornberger explained, ‘This probably explains why losing your way can be among the first signs of Alzheimer’s disease.’
If you or someone you love has started to notice these changes, it’s worth paying attention—even if everything else seems fine.
What happens next?
As the disease progresses, it enters a second phase marked by the build-up of tau and amyloid proteins.
While most people will have some of these proteins in their brains as they age, in Alzheimer’s, they clump together to form plaques and tangles, disrupting communication between brain cells.
This is when the more familiar symptoms—memory loss, confusion, language difficulties, and problems with reasoning—begin to appear.
A recent study from Seattle analysed the brains of 84 people who had Alzheimer’s and found that even those with low levels of tau and amyloid already showed signs of decay, particularly in crucial inhibitory neurons.
Over time, this decay spreads to brain areas responsible for language and memory, compounding the damage.
The good news? Identifying these early changes could be a game-changer. Dr Mariano Gabitto, lead author of the Seattle study, believes that spotting the first neurons lost could help scientists develop treatments to protect them, potentially slowing or preventing further decline.
Dr Igor Camargo Fontana from the Alzheimer’s Association agrees: ‘The disease’s long pre-symptomatic and silent period creates opportunities for early detection, early intervention and even prevention of dementia symptoms.’
Dementia is a growing concern in Australia, with nearly half a million people currently living with the condition—a number expected to double by 2058.
Alzheimer’s disease is the most common cause, responsible for about 60 per cent of cases. The impact is not just personal, but economic: dementia is one of the leading causes of death and disability, costing the nation billions each year.
While age and genetics play a significant role, lifestyle factors are increasingly in the spotlight.
A recent South Korean study found that people with metabolic syndrome—a cluster of conditions including belly fat, high blood pressure, high blood sugar, high triglycerides, and low ‘good’ cholesterol—have a 24 per cent higher risk of early-onset dementia.
The risk jumps to 70 per cent for those with all five conditions. This is a wake-up call for all of us to monitor our blood pressure, waistline, and cholesterol, not just for our hearts but also our brains.
Have you or someone you know experienced subtle spatial awareness or navigation changes? Do you think these could be early signs of something more serious, or just part of getting older? We’d love to hear your thoughts and experiences—share your stories in the comments below.
Also read: Dementia cases set to soar: Four science-backed habits that could keep your mind sharp
