Psychiatry: disorder groups
Delirium, dementia & neurocognitive disorders
Neurocognitive disorders are declines in thinking, memory and attention caused by brain disease: delirium (sudden confusion) and dementia (gradual decline). Psychiatrists assess cognition, find causes and manage the behavioural symptoms that distress families most.
Depth by stage, Pre-U → Consultant (details)
What is it?
Delirium is an acute state of confusion that develops over hours or days, often in elderly or very ill hospital patients, caused by infection, medication, surgery, dehydration or alcohol withdrawal. It is a medical emergency, frequently missed, and raises the risk of death.
Dementia (major neurocognitive disorder) is a progressive decline in memory, thinking and daily functioning. Common causes are Alzheimer's disease, vascular disease, Lewy body disease and frontotemporal dementia. Mild neurocognitive disorder describes smaller changes that do not yet affect independence.
As Malaysia's population ages, dementia is becoming more common, and families often provide most of the care at home.
Why does a psychiatrist need it?
Psychiatrists are asked to assess confusion on medical wards, diagnose dementia, manage agitation, depression and psychosis in dementia, advise on capacity and safety, and support carers. Getting delirium and dementia right prevents harmful sedation and missed medical illness.
What level is expected at each stage?
Scale: 1. Aware → 2. Understands → 3. Applies → 4. Masters / Teaches. What the levels mean.
- Pre-UNot expected
- Pre-clinicalAwareLearns brain anatomy of memory and the pathology of Alzheimer's disease.
- ClinicalUnderstandsPerforms brief cognitive tests and knows the difference between delirium and dementia.
- HousemanshipAppliesRecognises and manages delirium in medical and surgical wards, finding and treating causes.
- Medical officerAppliesAssesses cognition, manages behavioural symptoms and contributes to capacity assessments.
- Psych traineeMasters / TeachesDiagnoses dementia subtypes, manages complex cases and advises on capacity and law.
- Specialist / consultantMasters / TeachesLeads memory and liaison services; old age subspecialists set standards.
What are the key topics?
Conditions
- Delirium (hyperactive, hypoactive, mixed)
- Dementia due to Alzheimer's disease
- Vascular dementia
- Dementia with Lewy bodies and Parkinson's disease dementia
- Frontotemporal dementia
- Dementia due to other causes: alcohol, HIV, head injury, prion disease
- Mild neurocognitive disorder
Assessment
- Delirium screening such as the 4AT or CAM
- Cognitive tests: MMSE, MoCA, Addenbrooke's Cognitive Examination
- History from family about onset and course
- Reversible causes: thyroid, vitamin B12, folate, infections, medications, depression ('pseudodementia')
- Neuroimaging (CT/MRI) and sometimes other investigations
- Capacity and risk assessment: driving, wandering, finances, cooking
Management
- Delirium: treat cause, reorientation, family presence, avoid sedatives where possible
- Dementia medicines: cholinesterase inhibitors (donepezil, rivastigmine, galantamine) and memantine
- Behavioural and psychological symptoms of dementia (BPSD): non-drug approaches first
- Antipsychotic risks in dementia (stroke, death); special caution in Lewy body dementia
- Carer support, advance care planning, legal matters such as powers of attorney
How is it learned and assessed?
- Pre-clinical neuroanatomy and pathology
- Medical and geriatric postings in clinical years and housemanship
- Old age and liaison rotations in psychiatric training
- MMed Part I and II; MRCPsych Paper A (neuroscience) and B; CASC (cognitive examination, explaining dementia diagnosis)
Typical textbooks and resources
- Shorter Oxford Textbook of Psychiatry — Oxford University Press
- Lishman's Organic Psychiatry — Wiley-Blackwell
- Oxford Textbook of Old Age Psychiatry — Oxford University Press
- MOH Malaysia Clinical Practice Guidelines on dementia — Ministry of Health
Titles are widely used examples; editions change. Use university libraries or legitimate purchases.
Common questions
What is the difference between delirium and dementia?
Delirium starts suddenly, fluctuates and is usually caused by an acute illness or medication; it can often be reversed. Dementia develops gradually over months to years and is usually progressive.
Can dementia be cured?
Most types cannot be cured, but some causes of memory problems are treatable, and medicines, support and planning can improve quality of life for the person and family.