All of the following are true about delirium and dementia EXCEPT _________.

Delirium and dementia are the most common causes of cognitive impairment. Delirium and dementia are separate disorders but are sometimes difficult to distinguish. One of the differences between delirium and dementia is that the former emerges suddenly with a definite beginning point whereas the latter’s onset is slow and gradual, making it difficult to determine the exact date on which dementia started.