Dependence on benzodiazepines in patients with panic disorder: a cross-sectional study.

Aims: The aim of this cross-sectional study was to examine the prevalence of psychological dependence on benzodiazepines in outpatients with panic disorder and elucidate demographic and clinical characteristics associated with this condition.
Methods: Subjects were eligible if they were outpatients in four clinics in Tokyo, Japan, aged 18 years or older and met the diagnostic criteria for panic disorder according to the ICD-10. The subjects received the following assessments: the Severity of Dependence Scale, Japanese Version (SDS), the Self-Report Version of Panic Disorder Severity Scale, Japanese Version (PDSS-SR), and the Quick Inventory of Depressive Symptomatology-Self Report, Japanese Version. The following information was also collected: age, sex, ethnicity, duration of illness, physical and psychiatric comorbidities, and details of prescribed psychotropic medications.
Results: The data from 51 outpatients showed that 31 patients (60.8%) showed psychological dependence (i.e. a total score of ≥5 in the SDS). The proportion of patients with dependence was significantly lower in remitted patients (i.e. a total score of ≤4 in the PDSS) (44.1%, n = 15/34) than those who were not (94.1%, n = 16/17) (Pearson χ(2)  = 11.9, P < 0.001). A multiple regression analysis showed that the PDSS scores showed a positive correlation with the SDS total scores (β = 0.60, 95% confidence interval = 0.30-0.90, P = 0.0001).
Conclusion: These findings emphasize the need for enhanced awareness about benzodiazepine dependence in patients and psychiatrists, as well as especially close attention to patients with panic disorder who present severe symptomatology.
(© 2014 The Authors. Psychiatry and Clinical Neurosciences © 2014 Japanese Society of Psychiatry and Neurology.)