Dementia is not simply forgetfulness or an inevitable consequence of ageing. It is a clinical syndrome caused by diseases that progressively affect memory, thinking, behaviour and the ability to manage everyday life. The most common cause is Alzheimer's disease, but other types include vascular dementia, dementia with Lewy bodies, Parkinson's disease dementia, frontotemporal dementia and mixed dementia. Establishing the correct diagnosis matters because treatment and prognosis differ between these conditions.

As a consultant geriatrician, I assess dementia as part of a whole-person comprehensive geriatric assessment rather than as a single issue — reviewing memory alongside mood, function, medication and general health, since conditions such as depression, medication side effects, hearing loss, thyroid disease and vascular risk can all mimic or compound cognitive symptoms.

What are the early signs of dementia?

Dementia often develops gradually. The first changes may be noticed by a spouse, relative or close friend rather than by the person experiencing them.

Possible early signs include:

• Repeatedly asking the same questions
• Forgetting recent conversations, appointments or events
• Difficulty finding words or following conversations
• Becoming confused about dates, places or familiar journeys
• Problems managing medication, bills or finances
• Difficulty planning, organising or completing familiar tasks
• Poor judgement or increased vulnerability to scams
• Changes in mood, motivation, personality or behaviour
• Loss of confidence when driving
• Increasing dependence on relatives for everyday activities

Occasional forgetfulness does not necessarily mean dementia. Similar symptoms may occur with depression, anxiety, poor sleep, medication side effects, thyroid disease, vitamin deficiencies, infection, delirium or other medical conditions.

Families who want more detail can read my separate guide: Early Signs of Dementia: What Families in Sheffield Should Not Ignore.

When should someone seek a dementia assessment?

An assessment should be considered when cognitive changes are:

• Persistent or progressively worsening
• Noticeable to relatives or carers
• Affecting work, driving, medication management or finances
• Interfering with cooking, shopping, household tasks or self-care
• Associated with personality change, hallucinations or unusual behaviour
• Creating concerns about safety or vulnerability

Seeking advice early does not mean that dementia will necessarily be diagnosed. However, it provides an opportunity to identify treatable causes, make an accurate diagnosis and plan appropriate support.

Diagnosis

How is dementia diagnosed?

There is no single test that can diagnose every type of dementia. Diagnosis requires information from several sources.

What happens after a dementia diagnosis?

Following assessment, I explain:

• The most likely type of dementia
• The evidence supporting the diagnosis
• Whether any additional investigation is required
• Available medication and non-drug treatments
• Driving and safety implications
• Recommended follow-up
• Support available for the patient and family

I provide a detailed report to the patient and their GP, with consent.

Treatment

Can dementia be treated?

There is currently no cure for the common degenerative dementias, but treatment can reduce symptoms and may help some people maintain function and independence for longer.

Treatment must be selected according to the type and severity of dementia, other medical conditions, pulse rate, medication burden and the person's preferences.

Donepezil and rivastigmine

Donepezil and rivastigmine are acetylcholinesterase inhibitors. They are commonly used for mild-to-moderate Alzheimer's disease and may also be used in some other dementias.

For Alzheimer's disease, I most commonly start with:

If it is tolerated, I usually review the patient after approximately four weeks and consider increasing the dose to:

Possible adverse effects include nausea, diarrhoea, disturbed sleep, vivid dreams, dizziness, loss of appetite and a slow pulse. Treatment must therefore be individualised.

If donepezil is not tolerated, a rivastigmine patch may be considered. The patch can be useful when gastrointestinal adverse effects, swallowing difficulties or problems with tablets are concerns.

For Parkinson's disease dementia, rivastigmine — usually as a patch — is often my preferred first treatment (see my Parkinson's disease assessment page).

When is memantine used?

Memantine works differently from donepezil and rivastigmine.

It may be considered:

• For moderate Alzheimer's disease when acetylcholinesterase inhibitors are contraindicated or not tolerated
• For severe Alzheimer's disease
• In addition to an acetylcholinesterase inhibitor when Alzheimer's disease has progressed to the moderate or severe stage
• In selected patients with dementia with Lewy bodies or Parkinson's disease dementia when acetylcholinesterase inhibitors cannot be used

For example, memantine may be more appropriate when there is significant intolerance or a contraindication such as clinically important bradycardia.

Medication decisions should follow the diagnosed dementia subtype. These drugs are not routinely appropriate for pure vascular dementia or frontotemporal dementia unless there is another relevant coexisting dementia.

NICE recommends acetylcholinesterase inhibitors and memantine only for defined clinical indications.

Shared care

Why are private prescriptions initially required?

Donepezil, rivastigmine and other dementia medicines are locally managed as specialist-initiated or shared-care medicines within South Yorkshire.

When treatment is initiated privately, I issue the initial private prescription and retain responsibility while the medicine is started and adjusted.

The usual pathway is:

1. I initiate treatment using a private prescription.
2. I review the patient after approximately four weeks.
3. If appropriate, I increase or adjust the dose.
4. A further review is arranged after another four weeks when clinically required.
5. Once the treatment is stable, optimised and tolerated, I ask the GP to consider taking over NHS prescribing under the applicable shared-care arrangement.

Transfer to the GP is not automatic. The GP must receive the relevant clinical information and agree to accept prescribing responsibility. Until shared care has been formally accepted, private prescriptions remain necessary.

This process ensures that adverse effects, pulse rate, tolerability and early response are assessed while treatment is being established.

Ongoing care

Why is a six-month review important?

Dementia is progressive, and a medication that was initially suitable may need to be reconsidered as the condition changes.

A six-month review can assess:

• Cognitive and functional change
• Medication benefit and adverse effects
• Ability to manage everyday activities
• Behavioural or psychological symptoms
• Falls, weight loss and physical health
• Driving and home safety
• Carer concerns and support needs
• Whether the diagnosis or treatment plan remains appropriate

If Alzheimer's disease has progressed into the moderate or severe stage despite donepezil treatment, adding memantine may be considered. A fall in a cognitive-test score alone does not determine treatment; the decision should also consider function, behaviour, carer observations and the overall clinical picture.

Regular review also helps identify unrelated problems — such as infection, depression, medication side effects or delirium — which can cause an apparent sudden deterioration.

What non-medication treatment can help?

Medication is only one part of dementia care. Other important measures include:

• Regular physical activity
• Treatment of hearing or visual impairment
• Good sleep and adequate nutrition
• Management of blood pressure, diabetes and vascular risk
• Social engagement and meaningful activity
• A predictable daily routine
• Medication supervision where necessary
• Occupational therapy and falls prevention
• Advance care planning and lasting power of attorney
• Practical and emotional support for carers

The best plan is individualised to the person's diagnosis, health, abilities, priorities and family circumstances.

Dementia in Sheffield – when to act

If you are concerned about memory loss, cognitive decline or changes in a relative's ability to manage everyday life, a comprehensive geriatric assessment can help clarify the cause and identify the most appropriate next steps. Early assessment provides the best opportunity to identify treatable contributors, establish the correct diagnosis and make a practical plan for treatment and future care.