Alzheimer’s & Dementia

These three terms get used as if they mean the same thing. They don’t.

Mild Cognitive Impairment (MCI)Mild Cognitive Impairment (MCI)The in-between stage. Memory or thinking is measurably worse than expected for your age, but daily life (paying bills, cooking, driving) is still independent. is the in-between stage. Memory or thinking is measurably worse than expected for your age. But daily life is still independent — you can still pay bills, cook, drive.

Each year, about 5–10% of people with MCI go on to develop dementia. A meaningful number actually get better. The MCI patients most likely to benefit from the new anti-amyloid drugs are those whose MCI is caused by Alzheimer’s.

Dementia is the umbrella term. It means cognitive decline has crossed the line into affecting daily independence — handling money, navigating, cooking, working.

Alzheimer’s disease is the most common cause of dementia. It is not the only one. Vascular dementia, dementia with Lewy bodiesDementia with Lewy bodies (DLB)A type of dementia featuring visual hallucinations, fluctuating alertness, and Parkinson-like movements. Antipsychotic medicines can be dangerous in DLB., and frontotemporal dementiaFrontotemporal dementia (FTD)Dementia where personality, judgement or language change before memory does. More common in younger-onset cases (under 65). can look similar early on.

Getting the right diagnosis matters. The treatments and outlook are different for each.

Most people with Alzheimer’s notice memory problems first. This is called the typical (amnestic) form. But Alzheimer’s can also start in less expected ways:

• Posterior Cortical Atrophy (PCA)Posterior Cortical Atrophy (PCA)An unusual form of Alzheimer's where vision and spatial skills are affected first. People get lost in familiar places, or struggle to read, despite normal eyesight. — vision and spatial skills go first. People get lost in familiar places or struggle to read despite normal eyesight.
• Logopenic primary progressive aphasia (lvPPA)Logopenic primary progressive aphasia (lvPPA)An unusual form of Alzheimer's where language is affected first. Word-finding pauses and halting speech are early signs. — language goes first. Word-finding pauses, halting speech.
• Frontal/dysexecutive variant — judgement, planning and behaviour change before memory.

These atypical forms are more common in younger-onset Alzheimer’s (under 65). They’re also commonly misdiagnosed early. A memory clinic with cognitive-neurology input is the right setting for these cases.

Early signs people commonly notice:

• Forgetting recent conversations. Repeating questions in the same hour.
• Trouble managing money, medications, or following recipes.
• Getting lost driving in familiar areas.
• Misplacing things and not being able to retrace steps.
• Word-finding pauses, especially for names.
• Personality changes — withdrawal, irritability, suspiciousness.
• Sleep disturbance.

What is not normal ageing:

• Forgetting that a conversation happened at all (vs forgetting a detail).
• Getting lost on a regular route.
• Asking the same question several times in a single conversation.

If two or more of these are present and getting worse — talk to your GP about a memory-clinic referral.

Alzheimer’s is driven by two abnormal proteins building up in the brain over years — beta-amyloid plaques and tau tangles. Inflammation and brain-cell loss follow.

Biggest risk factors:

• Age is the strongest single risk. Risk roughly doubles every five years after 65.
• Family history moderately increases risk. Less than 1% of cases are directly inherited (genes APP, PSEN1, PSEN2) and these usually start younger.
• APOE ε4APOE ε4The strongest common gene variant linked to Alzheimer's risk. Carrying one copy roughly doubles risk; two copies (homozygote) raises it more, but it is not a guarantee. is the strongest common gene variant linked to risk. It is not a guarantee. Many people with APOE ε4 never develop Alzheimer’s.
• Cardiovascular — high blood pressure, diabetes, high cholesterol, smoking, no exercise.
• Hearing loss, social isolation, untreated depression.
• Head injury, particularly with loss of consciousness.
• Excessive alcohol, untreated sleep apnoea.

The big news: about a third of dementia is potentially preventable by addressing these factors across life (Lancet Commission on Dementia Prevention, 2024).

Before settling on Alzheimer’s, a memory clinic will rule out other causes. Several look similar but are different:

• Dementia with Lewy bodies (DLB) — visual hallucinations, day-to-day fluctuations, vivid dreams that are acted out, and Parkinson-like movements. Important: antipsychotic medicines can be dangerous in DLB.
• Vascular cognitive impairment — stepwise decline. Stroke history. Planning/executive problems lead.
• Frontotemporal dementia — personality and language change come before memory.
• Normal pressure hydrocephalus (NPH)Normal pressure hydrocephalus (NPH)Fluid build-up around the brain. Causes a triad of walking problems, urinary urgency, and cognitive decline. Sometimes reversible by inserting a shunt. — walking problems + urinary urgency + cognitive decline. Sometimes reversible with a shunt.
• Reversible mimics — vitamin B12 deficiency, thyroid disease, depression, sleep apnoea, medication side effects (especially anticholinergic and benzodiazepine load — often overlooked).

This is why a thorough memory-clinic work-up matters. A diagnosis isn’t rushed.

There is no single test for Alzheimer’s. The diagnosis is built from several pieces:

Cognitive (memory and thinking) tests. A memory clinic uses pen-and-paper tests like ACE-IIIACE-IIIAddenbrooke's Cognitive Examination III — a 100-point pen-and-paper test of attention, memory, fluency, language, and visuospatial skills. Takes about 20 minutes. or MoCAMoCAMontreal Cognitive Assessment — a faster pen-and-paper test (about 10 minutes). Score under 26/30 is a positive screen. in the room. Formal neuropsychology testing — a longer, deeper assessment — is used when the picture is subtle, atypical, or in younger patients.

MRI brain scan. A specific protocol looks at the hippocampus (the brain’s memory area) and rules out other causes — tumours, strokes, fluid build-up. CT is a fallback if MRI isn’t possible.

Blood tests. A standard panel rules out treatable contributors — vitamin deficiency, thyroid problems, diabetes.

BiomarkersBiomarkerA measurable sign in the body (blood, spinal fluid, or a scan) that helps diagnose a disease. are newer tests that look directly for Alzheimer’s pathology. They’re used when treatment decisions hinge on the diagnosis:

• Spinal fluid (CSF) tests via lumbar puncture — measure amyloid and tau proteins directly.
• Plasma p-tau217 — a new blood test with high accuracy. Now available in Australia through Sonic/Healius pathology. Currently you pay out of pocket (no Medicare rebate). It’s used as a helpful clue, not a stand-alone diagnosis. Results can be unreliable in kidney disease, very advanced age, or other illness.
• Amyloid PET scan — confirms amyloid in the brain. Not Medicare-rebated; expect about $1,000–$1,500 self-funded.

Section last verified · 26 April 2026

This is the biggest development in Alzheimer’s care in 20 years.

For decades, all Alzheimer’s medicines only treated the symptoms. The new drugs are different — they slow the disease itself.

Lecanemab (brand name Leqembi) and Donanemab (brand name Kisunla) are a new type of medicine. They are monoclonal antibodies — laboratory-made proteins given by drip into a vein. They clear amyloid out of the brain. In trials, they slow how quickly Alzheimer’s worsens in early disease.

Where things stand in Australia (April 2026)

• Lecanemab is approved by the TGA (2024) with a restricted label. People who carry two copies of APOE ε4APOE ε4 (homozygotes)People with two copies of APOE ε4 are excluded from some lecanemab labels because their side-effect risk (especially ARIA) is too high. are excluded because their side-effect risk is too high.
• Lecanemab is not on the PBS. Families pay out of pocket. Cost runs into five figures per year.
• Donanemab is still being assessed by the TGA. Currently accessed via clinical trials and selected private pathways.
• Treatment happens at specialist memory clinics with infusion capacity.

Who can have it — eligibility

• Confirmed amyloid in the brain on a PET scan or spinal fluid test (a blood test alone is generally not enough to start treatment).
• Early Alzheimer’s only — MCI from Alzheimer’s, or mild Alzheimer’s dementia.
• An MRI showing the brain is in acceptable shape for treatment (low risk of ARIAARIAAmyloid-Related Imaging Abnormalities — small areas of brain swelling (ARIA-E) or microbleeds (ARIA-H) that can appear on MRI during anti-amyloid treatment. Usually mild and silent, but require monitoring. — a known side effect of these drugs).
• An APOE ε4 gene test before starting.
• Anticoagulant (blood-thinning) medicines are generally a contraindication — combining them with anti-amyloid antibodies has been linked to dangerous bleeding.
• Regular MRI scans during treatment to watch for ARIA.

Cholinesterase inhibitors — donepezil, rivastigmine (tablet or skin patch), galantamine. They improve thinking and daily function in mild-to-moderate Alzheimer’s. Available on the PBS with Authority criteria. Common side effects: slow heart rate, fainting. Reviewing other medicines that worsen memory (anticholinergic and benzodiazepine medicines) is one of the highest-yield steps in dementia care.

Memantine is used in moderate-to-severe Alzheimer’s. Can be combined with a cholinesterase inhibitor. It treats symptoms, not the disease itself.

Treating the heart and blood vessels. Blood pressure, diabetes, cholesterol, stopping smoking. This is the single most underrated dementia treatment.

Lifestyle. Aerobic exercise. Hearing aids if needed. Staying socially engaged. Treating sleep apnoea. Treating depression.

Seizures. A meaningful minority of people with moderate-to-advanced Alzheimer’s develop seizures. New “spells” or unexplained falls warrant review and an EEG.

Behavioural and psychological symptoms (BPSD). Try non-medicine strategies first. Antipsychotics carry real cardiovascular and mortality risk. They should be time-limited if used at all — and avoided in suspected DLB. The Dementia Behaviour Management Advisory Service (DBMAS, 1800 699 799) is an excellent free resource for carers and clinicians.

A first memory-clinic appointment usually takes 60–90 minutes.

Bring with you

• Your GP referral letter
• A current medication list (including supplements and over-the-counter pills)
• A short written timeline of what’s changed and when
• Your Medicare card
• Bring the family member who has noticed the changes. What they describe is often more revealing than what the patient will remember to mention.

What the clinician will do

• Listen carefully to your story and theirs
• Run a memory and thinking test (usually ACE-III or MoCA)
• Do a brief neurological examination
• Review any prior scans or blood tests

What you’ll leave with

An initial impression. A plan for any further testing — typically blood tests, an MRI, sometimes formal neuropsychology. A follow-up date. The first visit is also a good time to start the practical conversations — driving, decision-making, advance planning — early, while there’s time to make choices on your own terms.

Australian driving standards are set by Austroads’ Assessing Fitness to Drive (2022).

A diagnosis of dementia does not always mean stopping driving on day one. It does mean a conditional licence, ongoing review, and often a formal on-road OT-DRIVE assessment (an occupational therapist who specialises in driver fitness).

In NSW, the driver is legally required to notify Transport for NSW. Doctors are protected when reporting in good faith.

These conversations are best had early, while the person can still take part in them.

• Enduring Power of Attorney (financial) — appoint someone you trust to make financial decisions if you can’t.
• Appointment of Enduring Guardian (NSW) — appoint someone for lifestyle and medical decisions.
• Advance Care Directive — your wishes for future medical care.
• Will review.

If you’re reading this because someone you love is unwell, you’re carrying a lot. Carer burnout is real and treatable.

Two things worth doing this week:

• Call the Dementia Australia National Helpline on 1800 100 500 — free, confidential, 7 days.
• See your own GP for a Mental Health Care Plan.

You’ll be a better carer if you take care of yourself first.

• Dementia Australia National Helpline — 1800 100 500 (free, 7 days)
• Dementia Australia — dementia.org.au
• My Aged Care — myagedcare.gov.au
• NDIS — ndis.gov.au
• Brain Foundation Australia — brainfoundation.org.au
• DBMAS (behaviour management advisory) — 1800 699 799
• Carers Australia — 1800 422 737
• Lifeline (mental health crisis) — 13 11 14
• NSW Trustee & Guardian — tag.nsw.gov.au