Delirium vs. Dementia vs. Depression

Delirium: Onset

Sudden (over hours to day) and fluctuating during the course of the day

Dementia: Onset

Slowly, over months and years

Depression: Onset

May have been gradual with exacerbation during crisis or stress

Delirium: Cause/Contributing Factor

Underlying medical condition such as a urinary tract infection, substance intoxication, or effects of medications

Dementia: Cause/Contributing Factor

• Alzheimer’s disease

• Vascular disease

• Human immunodeficiency Virus Infection

• Neurological disease

• Chronic alcoholism

• Head trauma

Depression: Cause/Contributing Factor

• Lifelong history

• Losses

• Loneliness

• Crises

• Declining health

• Medical conditions

Delirium: Cognition

• Impaired attention span

• Memory deficit

• Disorientation

• Disturbances in perception

• Not related to other cognitive disorders or reduced level of arousal

Dementia: Cognition

• Impaired memory

• Judgment

• Calculations

• Attention Span

• Abstract Thinking & Agnosia

Depression: Cognition

• Difficulty concentrating

• Forgetfulness

• Inattention

Delirium: Activity Level

• Can be increased or reducededreduced

• Restlessness, behaviors may worsen in evening (sundowning)

• Sleep-wake cycle may be reversed

Dementia: Activity Level

• Not altered

• Behaviors may worsen in evening (sundowning)

Depression: Activity Level

• Usually decreased

• Lethargy, fatigue, lack of motivation

• May sleep poorly and awaken in early morning

Delirium: Emotional State

• Rapid swings

• Can be:

  • Fearful

  • Anxious

  • Suspicious

  • Aggressive

  • Have hallucinations and/or delusions

Dementia: Emotional State

• Flat

• Agitation

Depression: Emotional State

• Extreme sadness

• Apathy

• Irritability

• Anxiety

• Paranoid ideation

Delirium: Speech & Language

• Rapid

• Inappropriate

• Incoherent

• Rambling

Dementia: Speech & Language

• Incoherent

• Slow (sometimes due to effort to find the right word)

• Inappropriate

• Rambling

• Repetitious

Depression: Speech & Language

• Slow

• Flat

• Low

Delirium: Prognosis

Reversible with proper and timely treatment

Dementia: Prognosis

Not reversible; progressive

Depression: Prognosis

Reversible with proper and timely treatment