Characteristics, interventions, and outcomes of misdiagnosed delirium in cancer patients

Although delirium is a common psychiatric complication in cancer patients, it is often not accurately recognized. To date, the characteristics and outcome of misrecognized patients are unclear in the cancer setting. This retrospective study was planned to determine the recognition by oncologists at the psychiatric consultation, characteristics, reversibility and outcome of misrecognized patients with delirium.

We reviewed charts of 60 patients diagnosed with delirium by the psycho-oncologists who were referred to the psychiatric consultation by the oncologists. Information about demographics, initial assessment by the oncologists, delirium subtype, precipitating factors, intervention for delirium, reversibility, and final status was obtained.

Twenty-two among 60 delirious patients were misrecognized by the oncologists at the time of consultation. They were often diagnosed as having anxiety or other psychiatric disorders. Misrecognized participants were significantly younger than accurately recognized cases of delirium. The psychiatrists made suggestions to the oncologists for all the referred patients, even when they were accurately diagnosed with delirium before consultation. For the correctly recognized patients, the main suggestion was pharmacological reevaluation. For the misdiagnosed cases, the psychiatrists suggested a reconsideration of the strategy for cancer treatment and the provision of information to the patient's family members about their condition.

Despite its high prevalence, delirium is difficult to diagnose for non-psychiatric physicians. Its detection is important not only to give the best treatment option to cancer patients but also to provide the best opportunity to inform their family about their condition and end-of-life issues.