Comparing Delirium and Dementia
Feature |
Delirium |
Dementia |
|
Development |
Sudden, sometimes with a definite beginning point |
Slow, with an uncertain beginning point |
|
Cause |
Almost always another condition, such as an infection, dehydration, or use or stopping of certain drugs |
Usually a brain disorder, such as Alzheimer disease, vascular dementia, or dementia with Lewy bodies |
|
Main early symptom |
Inability to pay attention |
Loss of memory, especially for recent events |
|
Effect at night |
Almost always worse |
Often worse |
|
Level of alertness (consciousness) |
Impaired to varying degrees, can vary from being hyperalert to sluggish |
Normal until late stages |
|
Orientation to surroundings |
Varies |
Impaired |
|
Effect on language |
Slowed speech, often with incoherent and inappropriate language |
Sometimes difficulty finding the right word |
|
Memory |
Varies |
Lost, especially for recent events |
|
Progression |
Causes variations in mental function—people are alert one moment and sluggish and drowsy the next |
Slowly progresses, gradually but eventually greatly impairing all mental functions |
|
Duration |
Days to weeks, sometimes longer |
Almost always permanent |
|
Need for treatment |
Immediate |
Needed but less urgently |
|
Effect of treatment |
Usually resolution of the symptoms |
May slow progression but cannot reverse or cure the disorder |