Atypical Antipsychotics for the Treatment of Delirious Elders

Background

Delirium occurs frequently in hospitalized patients and is reported to occur at a rate of 10% to 40% in hospitalized elderly patients. The gold standard of treatment is to treat the underlying cause of delirium and use high-potency antipsychotics such as haloperidol to target the behavioral disturbances. Since the development of atypical antipsychotics, many psychiatric conditions that were previously only treatable using high-potency antipsychotics may now be managed with the atypical agents. This review will examine the current literature on atypical antipsychotics and summarize the results from published trials in order to evaluate the efficacy and potential benefits of atypical antipsychotics for the treatment of delirium in the elderly population.

Methods

A search of the published literature was conducted using MEDLINE and PubMed. The PubMed search was limited to articles that were (1) written in the English language, (2) focused on human subjects above age 65, and (3) were in the format of review articles, randomized controlled trials (RCTs), clinical trials, or meta-analyses. The initial PubMed search was conducted in March 2006 with follow-up investigations in April 2006 and July 2007.

Results

Risperidone, the most thoroughly studied atypical antipsychotic, was found to be approximately 80% to 85% effective in treating the behavioral disturbances of delirium at a dosage of 0.5 to 4 mg daily. Studies of olanzapine indicated that it was approximately 70% to 76% effective in treating delirium at doses of 2.5 to 11.6 mg daily. Very few studies have been conducted using quetiapine; it also appears to be a safe and effective alternative to high-potency antipsychotics. In comparison to haloperidol, the frequency of adverse reactions and side effects was found to be much lower with the use of atypical antipsychotic medications. In the limited number of trials comparing atypical antipsychotics to haloperidol, haloperidol consistently produced a higher rate (an additional 10% to 13%) of extrapyramidal side effects.

Conclusions

A review of current literature supports the conclusion that atypical antipsychotic medications demonstrate similar rates of efficacy as haloperidol for the treatment of delirium in the elderly patient, with a lower rate of extrapyramidal side effects. There is limited evidence of true efficacy, since no double-blind placebo trials exist.

Keywords: Atypical antipsychotics, delirium, elderly