The effects of cognitive-behavior therapy for panic disorder on comorbid conditions.

In a replication and extension of prior research (Brown, Antony, & Barlow, 1995) examining the impact of treatment on additional diagnoses, our study investigated the effects of cognitive-behavioral treatment for panic disorder on frequency and severity of comorbid conditions in 33 principal panic disorder patients. Patients were diagnosed using the Anxiety Disorders Interview Schedule-Revised (ADIS-R; Di Nardo & Barlow, 1988) and assigned severity ratings indicating degree of distress and/or impairment for both principal panic disorder and comorbid conditions. A high rate of comorbidity (63.6%) was found at pretreatment. Following cognitive-behavioral treatment, there was a significant reduction in the number of patients with at least one additional diagnosis (p < .01); the greatest declines were found in comorbid social phobia and generalized anxiety disorder. Severity ratings also declined significantly from pre- to posttreatment for comorbid social phobia, generalized anxiety disorder, and posttraumatic stress disorder (p < .01) and were marginally significant for depression. There was a trend for comorbidity to reduce likelihood of achieving high improvement in panic at posttreatment. Implications of these findings for classification and treatment mechanisms are discussed.