Cognitive and Guided Mastery Therapies for Panic Disorder with Agoraphobia: 18-Year Long-Term Outcome and Predictors of Long-Term Change

In this study, we wished to compare the long-term outcome of (medication-free) panic disorder with agoraphobia patients randomized to cognitive or guided mastery therapy. Thirty-one (67.4%) of 46 patients who had completed treatment were followed up about 18years after end of treatment. In the combined sample and using intent-to-follow-up analyses, there were large within-group effect sizes of -1.79 and -1.63 on the primary interview-based and self-report outcome measures of avoidance of situations when alone, and 56.5% no longer had a panic disorder and/or agoraphobia diagnosis. No outcome differences between the two treatments emerged. Guided mastery was associated with greater beneficial changes in catastrophic beliefs and self-efficacy. For two of five outcome measures, more reduction in panic-related beliefs about physical and mental catastrophes from pre- to post-treatment predicted lower level of anxiety from post-treatment to 18-year follow-up when the effect of treatment changes in (a) self-efficacy and (b) anxiety was controlled. However, for one of the outcome measures, this effect attenuated with time. Copyright (c) 2014 John Wiley & Sons, Ltd.