Secondary depression in transdiagnostic group cognitive behavioral therapy among individuals diagnosed with anxiety disorders

•Anxiety and depression are often comorbid. Transdiagnostic treatments may affect comorbidity more than diagnosis-specific protocols.•We examined changes in anxiety and depression in transdiagnostic group CBT for anxiety (TGCBT) in individuals with and without depression.•After 12 weeks of TGCBT, those with comorbid depression were compared to those without on indices of anxiety and depression.•Anxiety improved in all although the depressed group scored higher at pre-treatment. Depressive symptoms reached sub-clinical levels in all.•TGCBT appears to be an effective option for treating anxious patients with comorbid depression, presenting an efficient tool for clinicians.

Anxiety and depression co-occur at high rates, and their comorbidity typically creates a more severe clinical presentation then either alone. The effect of comorbid depression appears to vary across anxiety and related disorders. Transdiagnostic treatments present a promising option to improve comorbid conditions by targeting shared factors (e.g., information processing biases). The purpose of this study was to examine the reciprocal effects of secondary depression in transdiagnostic group cognitive behavioral therapy for anxiety (TGCBT). 120 individuals diagnosed with a primary anxiety disorder, 42 of whom had a depressive diagnosis, were enrolled in 12 weeks of TGCBT. Depressed individuals were compared to those without a depressive diagnosis on both clinician-rated and self-reported anxiety and depression following TGCBT. Although depressed individuals scored higher on most indices of anxiety at pre-treatment, both groups improved similarly with some evidence of greater improvement among those with comorbid depression. All individuals improved in self-reported depressive symptoms and comorbid depression improved to subclinical levels. These results posit TGCBT as an effective, efficient option for treating patients with anxiety and comorbid depression.