Delirium: a test of the Diagnostic and Statistical Manual III criteria on medical inpatients.

Although 10% to 15% of patients admitted to acute care hospitals are in a state of delirium, few patients are given this diagnosis by their clinician. We field-tested the Diagnostic and Statistical Manual III (DSM-III) criteria for diagnosing delirium on 133 consecutively admitted patients to an acute medical ward. Twenty patients were delirious using DSM-III criteria, 19 more patients than were reported by the primary clinician. Seven delirious patients were less than 65 years of age (range, 32 to 64 years). Sixty-five percent of patients with delirium died, whereas significantly fewer (3.3%) of patients without delirium died (P less than .0001). We found that delirium could be readily and reliably detected (kappa coefficient of agreement = 0.62 for interrater reliability) using the DSM-III criteria. Clinicians should routinely screen hospitalized patients of all ages using DSM-III criteria to identify delirious patients for an immediate evaluation and treatment.