Dementia Assessment and Differentials:: PLAB 2 Mock 1st attempt

Practice a case with the AI patient 🤖

Summary:

This station involves assessing a patient with memory loss to differentiate between acute (delirium) and chronic (dementia) causes, conduct a focused MMSE within time constraints, and formulate an appropriate management plan while demonstrating structured data gathering and patient-centred communication.

Key Points

Main topic/system involved: Cognitive Neurology and Psychiatry

• Differential Diagnosis

  • Differentiate delirium (acute confusion, often reversible, e.g. infection, hypoxia) from dementia (chronic progressive cognitive decline).

  • Important questions:

    • Is this an acute or chronic presentation?

    • Onset, duration, and progression of symptoms.

• Types of Dementia

  • Alzheimer’s disease – progressive memory loss

  • Vascular dementia – history of strokes or vascular risk factors

  • Frontotemporal dementia – behavioural changes, speech disturbances, lack of insight

  • Parkinsonism-related dementia – tremors, rigidity

• Relevant History to Elicit

  • Family history of dementia

  • Past medical history (stroke, Parkinson’s, depression)

  • Associated symptoms: tremors, speech issues, hallucinations (psychosis)

Mini-Mental State Examination (MMSE) Approach

• Orientation – Time (day, date, month, year), Place (country, county, hospital)

• Registration and Recall

  • State three random words and ask immediate repetition (registration), followed by delayed recall after a distractor task.

• Attention

  • Tasks such as spelling “WORLD” backwards or serial sevens.

• Language

  • Phrase repetition: “No ifs, ands or buts.”

• Praxis

  • Normally includes drawing tasks, but omitted in telephone consultations.

Telephone Consultations Consideration

• Focus on aspects feasible without visual cues:

  • Orientation, registration, attention, recall, language.

• State that a full MMSE will be done in clinic for comprehensive assessment.

Important Considerations

• Always differentiate delirium from dementia at the outset.

• Assess insight – patients with frontotemporal dementia often lack insight.

• Rule out psychosis with questions on hallucinations or thought interference.

• Time management:

  • Ask one or two questions per MMSE domain to identify deficits efficiently within 8 minutes.

• Clearly introduce MMSE to the patient before starting.

• If significant deficits are found, move to management promptly rather than completing full MMSE.

Diagnostic Approach

1. Establish if acute (delirium) or chronic (dementia)

2. Identify onset, progression, and impact on daily life

3. Check family and medical history

4. Conduct focused MMSE:

   • Orientation: time/place (5 questions each)

   • Registration and recall: three objects

   • Attention: WORLD backwards or serial sevens

   • Language: phrase repetition

5. Evaluate for psychosis symptoms if suspected

6. Formulate differential diagnosis based on findings

Management

• Explain suspected diagnosis sensitively.

• Arrange:

  • Blood tests (FBC, U&E, LFTs, calcium, TFTs, B12, folate)

  • Neuroimaging (CT/MRI) if needed

  • Referral to Memory Clinic / Elderly Care / Neurology / Psychiatry

• Provide supportive resources to patient and family.

• Advise on safety-netting (e.g. worsening confusion, risk to self).

Communication Skills

• Empathise with memory concerns, validate their distress.

• Avoid rehearsed phrases; remain natural.

• Signpost transitions: e.g. “I’d like to ask you some questions to assess your memory.”

• Avoid unnecessary assurances or overpromising services.

Ethical Considerations

• Consent and capacity assessment before MMSE.

• Confidentiality, especially during collateral history taking.

• Consider safeguarding if self-neglect or abuse is suspected.

Additional Resources

• NICE CG42: Dementia – Assessment, management and support

• GMC Good Medical Practice (2024)

• PLAB 2 examiner top tips for psychiatry and cognitive assessment stations