title: Low levels of acetylcholine in later years contributes to confusion.
abstract: Delirium is a state of confusion that is usually of abrupt onset and short duration. It is particularly associated with increasing age. One possibility is that, with age, the blood/brain barrier becomes more permeable, making older people more susceptible to toxins. It is also known that delirium is associated with reduced acetylcholine in the brain. People with dementia may already have low levels of acetylcholine so they are at particular risk and can become delirious with even minor physical problems such as constipation. Failure to identify and treat the underlying cause increases mortality and increases the length of hospital stays.