January 15, 1999

APA's Board of Trustees approved a set of practice guidelines on the treatment of patients with delirium last month at its meeting in Denver. It is the 10th APA practice guideline.

Delirium was selected by APA's Steering Committee on Practice Guidelines because it is a major psychiatric disorder that affects between 10 percent and 30 percent of the hospitalized medically ill and between 10 percent and 40 percent of the hospitalized elderly. As many as 51 percent of postoperative patients develop delirium and as many as 80 percent of those with terminal illnesses develop delirium near death, according to the guideline.

Work group chair Paula Trzepacz, M.D., told Psychiatric News that the disorder has high morbidity and mortality rates.

"Although delirium is usually reversible, there is an abrupt and acute change in the patient's mental status," said Trzepacz, a professor of psychiatry and neurology at the University of Mississippi Medical Center in Jackson. "The sooner he or she is accurately diagnosed and treated, the better the chances of a good outcome."

However, "many studies show that the disorder is underdiagnosed and under-treated even after educating medical housestaff about delirium," she noted. "The psychiatrist in the role of consultant needs to educate the primary care physician about what tests to order for a thorough work-up and advocate for appropriate treatment. The consultant should continue to stay involved in the case."

The purpose of the 66-page guideline is to assist psychiatrists in caring for patients diagnosed with delirium according to DSM-IV criteria. The major sections inform the physician about the definition of the disease, epidemiology and natural history, treatment principles and alternatives, the formulation and implementation of a treatment plan, and clinical features influencing treatment.

The executive summary contains several recommendations rated numerically from one to three, with one being the highest, based on the work group's level of clinical confidence.

One highly rated recommendation states, "Antipsychotic medications are often the pharmacologic treatment of choice. Haloperidol is most frequently used because it has few anticholinergic side effects, few active metabolites, and a relatively lower likelihood to cause sedation and hypotension."

Trzepacz commented, "There is significant empirical evidence to support the use of haloperidol as the primary pharmacological treatment. But we need more controlled studies on the treatment of delirium.

Behind in Research

"In my opinion, we are behind in doing research in this area [compared with other psychiatric disorders]. In addition to studying efficacy, we need to look at how certain symptom profiles of delirium might respond differentially to specific pharmacological choices."

A statement that might be endorsed based on individual circumstances reads, "Patients with delirium who can only tolerate lower doses of antipsychotic medications may benefit from the combination of a benzodiazepine and antipsychotic medication."

Trzepacz emphasized the importance of making a differential diagnosis. A section in the guideline is devoted to describing the differences between delirium and dementia, which share some common features such as cognitive disturbances.

"Even psychiatric patients can become delirious at any time due to medical problems such as a toxic response to medications," states the guideline.

Treatment Complex

The authors emphasize that the treatment of patients with delirium is complex and involves the consideration of many factors. Common causes of delirium include general medical conditions and substance abuse withdrawal.

"Psychiatrists are uniquely positioned with their knowledge of medicine and behavioral syndromes to diagnose the disorder correctly," commented Trzepacz. "However, while looking for the underlying causes, the psychiatrist should not delay in treating the symptoms of delirium with medications such as haloperidol."

The authors also recommend supplementing the standard psychiatric, general medical, and neurological tests with formal screening and diagnostic instruments.

The new practice guideline will be published in a spring issue of the American Journal of Psychiatry. The work group members are William Breitbart, M.D., James Levenson, M.D., D. Richard Martini, M.D., John Franklin, M.D., and Philip Wang, M.D. (consultant).

To view the full text of APA's practice guidelines, visit APA's Web site at www.psych.org/clin--res/prac--guide.html. The delirium guideline will be online sometime in the spring. The other guidelines address eating disorders, major depression, bipolar disorder, substance abuse disorders, psychiatric evaluation of adults, Alzheimer's disease, panic disorder, schizophrenia, and nicotine dependence.