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 medications | 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 |