Differentiation of DSM-III-R anxiety disorders by severity of illness and symptom onset sequences.

187 patients were investigated by a structured interview for DSM-III-R and various clinicians' and patients' ratings. A high frequency of comorbidity between different anxiety disorders and between anxiety and depression was found. According to sociodemographic data, various anxiety disorders showed more similarities than differences. Patients with a generalized anxiety disorder showed an earlier age at onset compared to patients with panic disorder as well as a greater severity of illness and comorbidity. Avoidance behavior occurred before, simultaneous with, as well as after the onset of panic disorder.