Validation of the Generalized Anxiety Disorder-7 (GAD-7) in Russian people with epilepsy

To assess the capacity of Generalized Anxiety Disorder-7 (GAD-7) to detect anxiety disorders in a Russian sample of patients with epilepsy and to validate this instrument for rapid screening of anxiety in these patients.

Study included 233 patients with epilepsy, both inpatients and outpatients. For all patients Mini-International Neuropsychiatric Interview was conducted as a gold standard for diagnosis of mental disorders. All patients also completed the questionnaires - the Russian version of GAD-7 and Hospital Anxiety and Depression Scale (HADS) to assess convergent validity. Chi-square and Fisher's exact tests were used to compare categorical variables, and the Mann-Whitney test was used for the quantitative ones. Internal consistency was assessed using Cronbach's alpha, Cronbach's alpha at point deletion, and corrected point-to-point correlation. ROC analysis was used to evaluate the properties of the GAD-7 to determine anxiety disorders.

Among 97 (41.6%) patients with epilepsy diagnosed with any anxiety disorders, 42 (18%) had panic disorder, 37 (15.9%) had agoraphobia, 17 (7.3%) had social anxiety disorder, and 64 (27.5%) had generalized anxiety disorder; 42 patients (18%) showed a combination of several anxiety disorders. The overall GAD-7 score was similar to other epilepsy studies, but higher cutoff scores characterize our sample. The scale performed well in detecting any anxiety disorder with the AUC of 0.866 and the optimal cutoff point > 8 points, and in detecting GAD with AUC = 0.922 and the optimal cutoff point > 9 points, showing overall acceptable sensitivity.

Russian version of the GAD-7 could be used as a screening tool for any anxiety disorders in PWE with the optimal cutoff score > 8 points.