Underdiagnosis of psychoactive-substance-induced organic mental disorders in emergency psychiatry.

The tendency of emergency psychiatrists to make alcohol- and drug-related diagnoses was examined before and after the addition of a standardized psychoactive substance use questionnaire. The addition of the questionnaire resulted in a significant increase in the number of psychoactive-substance-induced organic mental disorder (substance-induced disorder) diagnoses. The questionnaire selectively increased the recognition of nonalcoholic substance-induced disorders while not significantly increasing the diagnoses of alcohol-induced disorders when alcohol was used alone. This suggests that nonalcoholic substance-induced disorders are underdiagnosed in emergency psychiatry. With the increase in the diagnoses of substance-induced disorders, there was a significant decrease in the frequency of psychotic disorder diagnoses and a significant increase in the frequency of adjustment disorder diagnoses. The clinical impact of underdiagnosing and misdiagnosing substance-induced disorders is discussed. Overall, the findings suggest that an increased awareness of substance use history, by the use of a standardized questionnaire, is an effective means of increasing the diagnostic yield of substance-induced disorders in the psychiatric emergency room. Follow-up studies using urine drug screening are recommended.