Delirium, dementia and why sudden change matters

Delirium and dementia can occur together but are different. Dementia usually appears gradually over months or years. Delirium develops over hours or days and often fluctuates between better and worse across the day and night.

NICE advises that when it is hard to distinguish delirium from dementia, or delirium occurs on top of existing dementia, the delirium should be managed first. This is important in care homes because many residents already have dementia or baseline cognitive impairment.

Why staff should not dismiss sudden change

• Existing dementia does not rule delirium out: dementia increases the risk of delirium.
• Acute confusion is not normal ageing: a sudden decline in attention, alertness or engagement requires prompt action.
• Fluctuation is a clue: being better at one time and much worse later can indicate delirium.
• Quiet change matters too: reduced conversation, slower movement and eating less can be warning signs.

Manager focus: baseline and review

When confusion changes suddenly, manage the acute change first. Do not let a dementia label hide a new problem.