Increased probability of remaining in remission from panic disorder with agoraphobia after drug treatment in patients who received concurrent cognitive-behavioural therapy: a follow-up study

Abstract

Background: Many short-term trials suggested that the combination of psychotherapy with medication might be more effective than either treatment alone. However, only few studies examined the long-term effectiveness of this combination.

Methods: A private practice sample of consecutive patients with DSM-III-R panic disorder with agoraphobia who achieved remission after drug treatment with or without concurrent cognitive-behavioural psychotherapy were followed up. Patients were assessed before treatment, after treatment and at each follow-up contact with the Marks-Sheehan Phobia Scale, the Hamilton Anxiety Rating Scale, and the Hamilton Depression Rating Scale. Kaplan-Meier survival analysis was performed on the time to panic disorder relapse. Cox regression analysis was used to control for the possible confounding effect of factors other than treatment.

Results: Of patients who received medication alone (n = 32), 25 (78.1%) relapsed, prevalently (65.6%) during the first year. The estimated mean survival time was 12 months (95% CI 7-17). Of patients who received integrated treatment (n = 21), only 3 (14.3%) relapsed. The estimated mean survival time was 65 months (95% CI 44-86). Treatment was the only variable associated with the occurrence of relapse, with a hazard ratio of 12.6 (95% CI 2.5-63.3) for patients who received only medication.

Conclusions: Some methodological limitations, such as treatment allocation by preference, suggest caution in the interpretation of our results. However, the long-term therapeutic advantage of integrated treatment over medication alone was large and independent from known prognostic factors. The long-term effectiveness of integrated treatment should be tested with a randomised controlled trial.