Depression and panic attacks: the significance of overlap as reflected in follow-up and family study data.

Ninety-one patients with panic attacks limited historically to depressive episodes had more severe depressive symptoms and were less likely to recover during a 2-year follow-up than 417 depressed patients who did not have panic attacks. Family study data clearly distinguished another 15 patients with panic disorder and secondary depression; interviewed relatives of panic disorder patients were significantly less likely to have primary depression and significantly more likely to have various anxiety disorders. These data support the hierarchical system by which many of the contemporary diagnostic systems separate panic disorder and major depression.