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

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.

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.

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).

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.