High prevalence of benzodiazepine dependence in out-patient users, based on the DSM-III-R and ICD-10 criteria.

Despite the fact that there have been many reports on benzodiazepine (BZD) dependence, consensus about its definition has not been reached. Reliable prevalence data to estimate the dependence liability of BZDs are therefore lacking. This study is the first to assess the prevalence of BZD dependence in out-patient BZD users (115-general practice (GP) patients, 124 psychiatric out-patients and 33 self-help patients) on the basis of the DSM-III-R and ICD-10 substance dependence criteria. Past year and lifetime diagnoses of BZD dependence were made by means of the Schedules for Clinical Assessments in Neuropsychiatry (SCAN). High prevalence figures were found, ranging from 40% in the GP patients (DSM-III-R past year) to 97% in the self-help patients (ICD-10 lifetime), indicating that BZD users run a high risk of developing BZD dependence. The clinical management of BZD use could benefit from further development of diagnostic instruments such as a self-report questionnaire which reflects the severity of BZD dependence.