| Prevalence |
Older adults are more likely than others to develop delirium. Between 14% and 24% of patients admitted to a hospital are delirious. Approximately 70–87% of people in intensive care may become delirious. Delirium occurs in up to 60% of nursing home residents. Up to 80% of terminally ill patients will become delirious at the end of life (Brown & Boyle, 2002). |
| Comorbidity |
Delirium may occur along with another neurocognitive disorder or as a result of a substance-related disorder. |
| Onset |
When delirium arises after head trauma, symptoms often develop immediately. |
| Course |
Delirium typically resolves, and does so sooner, when the underlying problem is treated. Symptoms of delirium typically fluctuate over the course of the day. For most people, symptoms completely subside within a few hours or days; for others, especially the elderly, symptoms may persist for months or longer. People who had relatively good health and cognitive functioning before their delirium began are likely to make a better recovery than those with poor health and cognitive functioning. People with previous episodes of delirium are vulnerable to subsequent episodes. |
| Gender Differences |
Among elderly people, men are more likely than women to become delirious. |
| Cultural Differences |
Countries have different guidelines for diagnosing delirium, which can prohibit making meaningful comparisons across countries (Leentjens & Diefenbacher, 2006). |
| Source: Unless otherwise noted, the source for information is American Psychiatric Association, 2013. |