9
Distinguishing the 3D's
Delirium Dementia Depression
Onset Acute (hours to
days)
Gradual (months to
years)
Gradual (weeks to
months)
Course Fluctuating Slowly progressive or
chronic
Usually reversible
with treatment
Consciousness Commonly altered Clear except in
advanced stages
Clear
Attention Impaired Intact except in
advanced stages
Generally intact
Mood Variable Variable Low
Apathy Present or Absent Present or Absent Present or Absent
Hallucinations Common in
hyperactive delirium
Usually absent,
except in Lewy body
dementia
Absent except in
depression with
psychotic features
Psychomotor
Changes
Hypoactive or
hyperacitve
Wandering, agitated,
or withdrawn in
some cases
Hypoactive or
hyperactive
Reversibility Usually reversible Not reversible Usually reversible
Signs of other
medical
condition
Present Absent Usually absent
