Residual symptoms and comorbidity in panic disorder.

Background: The aim of this study was to assess the outcome of the comorbid conditions of panic disorder after 1 year of treatment, emphasizing the detection of residual symptoms and their relationship to other clinical variables. Methods: Subjects (N = 64) were assessed by the Structured Clinical Interview for DSM-III-R and the Eysenck Personality Questionnaire. Comorbidity with other disorders, scores on Hamilton Anxiety Rating Scale and Hamilton Depression Rating Scale were assessed at baseline and after 12 months. Criteria for residual anxiety/somatic symptoms were defined. Results: Reduction in generalized anxiety disorder rates accounted for a significant decrease in comorbidity at 1-year follow-up, with regard to baseline assessment. When the more severe symptoms of the disorder had remitted, a third of the patients referred physical symptoms with some concern over a fluctuating state of anxiety. The said symptoms were neither a recurrence of panic disorder nor did they account for other anxiety or somatoform disorders. Lower scores on extraversion predict higher risk of residual symptoms. Discussion: The persistence of residual anxiety/somatic symptoms in a third of the patients who apparently achieved a good response to treatment of panic disorder might characterize a minor form of chronic persistence of this condition. Conclusions: The subgroup of patients with residual symptoms would not be detectable by follow-up studies, which focus on the assessment of relapse of panic disorder by means of strictly defined diagnostic criteria.