Delirium

People who can communicate when affected by delirium are usually confused and often show an impaired understanding of what is happening to them. They are often distressed and anxious. They may also believe that they are at personal risk, for example feeling that they have been imprisoned or that people who are offering assistance are trying to harm them. Visual hallucinations are also common and can be very frightening. Some people with delirium can appear very restless and hyperactive. This is often a consequence of fear in that they feel unsafe and want to leave to reach a place of safety or to be with family. During a period of delirium, the features can come and go (fluctuate). For example, a patient may be confused, disorientated and fearful at one point overnight but appear calmer and less confused hours later.

People with dementia have a higher risk of developing delirium. Dementia is different to delirium as it is typically caused by anatomical changes in the brain.

The differences between delirium and dementia are that dementia is a gradual onset, affects memory and is not reversible and usually progresses over time. In contrast, delirium develops rapidly, profoundly affects attention and is potentially reversible.