Synopsis
Assess persistent cognitive and functional decline using supported history, collateral and subtype-directed examination, separate delirium and treatable contributors from neurodegeneration, and plan diagnosis, capacity, safety and carer support without premature labelling.
- Dementia is acquired cognitive decline that interferes with everyday function; a low score without functional change does not establish it.
- First establish chronology and baseline through the person and collateral: memory, executive, language, visuospatial, behaviour, IADLs and ADLs.
- Exclude delirium first with 4AT when change is acute or fluctuating and reassess after acute illness, pain and communication barriers improve.
- Use a validated brief tool such as GPCOG in primary care, but do not exclude dementia solely because a normal score conflicts with convincing history.
- Check hearing, vision, language, education, motor and speech impairment before interpreting performance and record the test conditions.
- Review anticholinergic, sedative and opioid medicines, alcohol, sleep and mood and make cautious monitored changes when they plausibly contribute.
- Core examination includes neurological and gait assessment, parkinsonism, eye movements, focal signs and cardiovascular risk; function and home safety are equally important.
- Routine blood work commonly includes FBC, renal, liver, calcium, glucose or HbA1c, thyroid, B12 and folate, adapted to the clinical picture.
- Structural imaging is usually offered to exclude reversible lesions and support subtype unless dementia is already established and the result would not change care.
- Refer for specialist subtype assessment; discuss diagnosis, driving, advance planning, capacity, carer assessment, support and review in accessible language.
Key red flags
Rapid progression over weeks, seizures, focal deficits, early gait disorder, severe headache or systemic illness requires expedited neurological and medical investigation.
Acute fluctuation or inattention is delirium until assessed, even when family has noticed longer memory difficulty.
Getting lost, unsafe cooking, medication duplication, scams, driving incidents or self-neglect requires immediate functional and safeguarding risk mitigation.
Depression with suicide intent, psychosis, starvation or profound withdrawal needs same-day mental-health and medical review.
A screening score must not be used to infer global incapacity, mandate residential care or remove control of finances.
Strong anticholinergic or sedative burden, alcohol dependence and sensory loss may materially worsen cognition and must be addressed without promising full reversal.
Weeks-to-months progression, seizure or new focal finding requires expedited alternative-disease investigation.
Scams, wandering, unsafe cooking or medication errors require immediate risk mitigation while diagnosis proceeds.
Investigation priorities
Identify superimposed delirium before dementia interpretation.
Management branches
Persistent cognitive concern is raised by the person, carer or clinician.
- Optimise communication, use 4AT if acute change exists and obtain collateral cognition and function chronology.
- Complete validated cognitive, mood, medicine, sensory, neurological and targeted blood assessment.
- Arrange structural imaging and specialist subtype diagnosis unless results would not alter care.