Відмінності між делірієм та деменцією*

Feature

Delirium

Dementia

Onset

Sudden, with a definite beginning point

Slow and gradual, with an uncertain beginning point

Duration

Days to weeks, although it may be longer

Usually permanent

Cause

Almost always another condition (eg, infection, dehydration, use or withdrawal of certain medications)

Usually a chronic brain disorder (eg, Alzheimer disease, dementia with Lewy bodies, vascular dementia)

Course

Usually reversible

Slowly progressive

Effect at night

Almost always worse

Often worse

Attention

Greatly impaired

Unimpaired until dementia has become severe

Level of consciousness

Variably impaired

Unimpaired until dementia has become severe

Orientation to time and place

Varies

Impaired

Use of language

Slow, often incoherent, and inappropriate

Sometimes difficulty finding the right word

Memory

Varies

Lost, especially for recent events

Need for medical attention

Immediate

Required but less urgently

Effect of treatment

Usually reverses symptoms

May slow progression but cannot reverse or cure the disorder

* Differences are generally true and helpful diagnostically, but exceptions are not rare. For example, traumatic brain injury occurs suddenly but may result in severe, permanent dementia; hypothyroidism may produce the slowly progressive picture of dementia but be completely reversible with treatment.