Study design
- A literature review identified published and unpublished randomized controlled trials in English and Chinese in which cholinesterase inhibitors were compared with placebo or another drug for treating delirium in non-critically ill patients.6
- Only one study met the criteria to be included in the review. It included 15 participants treated with rivastigmine or placebo.
Outcomes
- The intended primary outcomes were severity of delirium and duration of delirium. However, the included study did not report on the severity of delirium. It also lacked statistical power to determine a difference in duration of delirium between the rivastigmine and placebo groups.
- Secondary outcomes included use of a rescue medication, persistent cognitive impairment, length of hospitalization, institutionalization, mortality, cost of intervention, early departure from the study, and quality of life.
- There was no clear difference between the rivastigmine group and the placebo group in terms of the use of rescue medications, mortality, or early departure from the study. The included study did not report on persistent cognitive impairment, length of hospitalization, institutionalization, cost of intervention, or quality of life.
Conclusion
- This literature review did not find any evidence to support the use of cholinesterase inhibitors for treating delirium. However, because this review included only a single small study, limited conclusions can be drawn from this research.
In summary, delirium is common, especially among patients who are acutely medically ill, and it is associated with poor physical and cognitive clinical outcomes. Because of these poor outcomes, it is important to identify delirium early and intervene aggressively. Clearly, there is a need for further research into short- and long-term treatments for delirium.