But what happens once the diagnosis finally comes?

For many families, that’s the moment they fear most. Yet after speaking with Dr Cheryl Johnson, lead geriatrician and head of Brightly’s neuro team, I’m increasingly convinced the diagnosis itself is not the problem. In many cases, it’s the beginning of the solution.

Why it’s so hard to get diagnosed

Diagnosing dementia properly isn’t quick.

That’s because a diagnosis isn’t simply about deciding whether someone has dementia. It’s about understanding what type of dementia it is, what stage it’s at and what that means for treatment, support and planning.

A thorough assessment can take three to four hours with a person and their family: taking a detailed history, assessing how memory changes are affecting everyday life, conducting cognitive testing, reviewing medications, arranging brain imaging where appropriate and discussing the diagnosis and treatment plan.

Compare that with the 10 or 15 minutes available in a standard GP appointment and it’s easy to see why diagnosis can be difficult to achieve quickly.

This isn’t negligence. It’s a specialist process squeezed into a generalist time slot.

“You can’t work it out from a memory test alone,” Johnson says.

“You need to understand how someone’s functioning, what the family is seeing, what medications they’re taking and how all of that fits together.”

That level of investigation matters because dementia isn’t a single disease.

“Dementia is an umbrella term,” Johnson says.

“Underneath it is a number of different conditions causing the memory decline.”

Alzheimer disease accounts for around 60-70% of cases, but vascular dementia, Lewy body dementia and frontotemporal dementia can all present differently and require different approaches.

“Sometimes people have more than one type,” Johnson says.

“Sometimes different dementias can look quite similar. That’s why getting the diagnosis right matters.”

Knowing which condition is present affects medication choices, treatment options and what families should expect over time.

Just as importantly, a diagnosis establishes the stage.

A person with mild cognitive impairment needs a different plan from someone with an established dementia diagnosis. Treatment options, support needs and opportunities to intervene are all different.

Why catching it early matters

Before dementia develops, many people pass through a period known as mild cognitive impairment, where memory or thinking has changed but day-to-day function remains largely intact.

Johnson describes it as a critical intervention point. Around 10–15% of people with mild cognitive impairment progress to dementia each year. Most don’t.

“The challenge for us as clinicians is working out which camp you’re in,” she says.

“Not everyone who presents with memory concerns has dementia. Some people have nutrient deficiencies, thyroid disorders, sleep apnoea, depression, hearing loss or medication interactions that can look remarkably similar.”

Research from the United States National Institutes of Health suggests that up to 23% of people assessed for cognitive concerns are ultimately found to have another, often treatable, cause for their symptoms.

For those in the earliest stages of dementia, timing can also affect treatment options.

“New anti-amyloid therapies, already approved overseas, are changing how Alzheimer disease is treated internationally. But they are designed for people in the earliest stages of disease. For this type, if we don’t pick people up early, we’ve missed a boat,” Johnson says.

She says existing medications can also help. Cholinesterase inhibitors improve or stabilise function in up to two-thirds of people with Alzheimer disease.

But Johnson is clear that diagnosis does not stop being valuable simply because someone presents later.

“People often think if we’ve missed the earliest window, there’s no point knowing,” she says. “I don’t agree with that.”

A diagnosis may not change the disease itself, but it can change how a family responds to it.

It can explain behaviours that have become difficult to understand. It can guide medication decisions. It can help families anticipate what’s coming rather than constantly reacting to it.

What good care looks like

For Johnson, diagnosis isn’t the destination: it’s the starting point.

A good assessment looks beyond a cognitive test score and asks what else might be influencing brain health. Sleep, hearing, medications, vitamin absorption, metabolic and cardiovascular health, diet, exercise and social connection all play a role.

Once a diagnosis is made, Johnson focuses on building a support plan around both the individual and their carer.

“It’s not just about making the diagnosis … It’s about understanding the problem, putting a plan in place and then walking alongside that person and their family.”

For many families, the first question after diagnosis is: what happens now?

Johnson says that’s often where traditional dementia care falls short.

Families are frequently given information about stages, progression rates and what the disease might look like over time. While that’s important, it doesn’t always answer the questions people are asking.

Dementia doesn’t follow a neat timetable. Two people with the same diagnosis can have very different experiences and trajectories.

Families want something practical:

Those are the questions that determine whether families stay ahead of change or find themselves constantly responding to crises.

“A lot of our work is helping families understand what matters now, what might matter next, and what signs should prompt a review,” Johnson says.

Because while a diagnosis explains what is happening, a plan helps prepare for what comes next.

The emotional, financial and practical strain often falls as heavily on the carer as it does on the person diagnosed.

In Johnson’s experience, one of the biggest questions is rarely spoken aloud: does this family have the capacity to adapt to what is coming?

“The last thing we want is for families to feel they’re on their own,” she says.

The hopeful part

A diagnosis opens doors. Sometimes those doors lead to treatment. Sometimes they lead to discovering that dementia wasn’t the problem at all. Often, they simply replace uncertainty with clarity.

The fear of “there’s no cure” is real, but it’s the wrong fear. The greater risk is leaving it too long to find out what’s going on.

5 things to do if you’ve noticed a change

1. Go straight to a specialist. No referral is needed – a geriatrician or specialist memory service can be accessed directly.

2. Rule out masquerading symptoms first. Fast-track clinical corrections. Up to 23% of memory concerns are something else entirely.

3. Act now, not at the next milestone. The earlier the diagnosis, the more treatments stay viable as some only work in early disease.

4. Plan for the carer too. Their health is part of the plan, not an afterthought.

5. Build family capacity, not just care. “How long do we have?” means “how do we make the most of it?” Invest and plan – for both money and support – before you need them.

Hannah McQueen is the founder and director of Age Brightly. She is also the host of The Next Bit podcast on iHeart Radio.