Geriatric Psychiatry and Neurocognitive Disorders
What the exam tests
Geriatric items test delirium versus dementia, dementia subtypes, depression, capacity and behavioural symptoms. Acute confusion is a medical emergency until proven otherwise.
Core rules
- Delirium is acute, fluctuating and associated with inattention; look for infection, drugs, pain, constipation, hypoxia and metabolic causes.
- Dementia is chronic progressive cognitive decline with preserved consciousness until late; Alzheimer disease is the commonest cause, followed by vascular dementia.
- Lewy body dementia shows fluctuating cognition, visual hallucinations and parkinsonism; antipsychotics can cause severe sensitivity reactions.
- Frontotemporal dementia presents early with personality and language change; vascular dementia is stepwise with focal signs.
- Depression can mimic dementia; MCI is cognitive decline with preserved daily function.
- Manage behavioural symptoms with environmental and psychosocial measures first; use antipsychotics cautiously and briefly.
Worked example
A 78-year-old becomes confused over two days after a urinary infection, with fluctuating attention and poor sleep. This is delirium, not dementia. The reasoning is acute onset, fluctuating course and inattention. Treat the infection, review drugs, reorient, hydrate and avoid restraints. Dementia may coexist, but the acute change needs urgent medical assessment.
Traps that cost marks
Do not label acute confusion as dementia. Do not miss anticholinergic burden, alcohol withdrawal or subdural haematoma. Do not give antipsychotics to a patient with suspected Lewy body dementia without weighing severe sensitivity. Do not equate depression with irreversible dementia without follow-up.