Relationship and chronology of depression, agoraphobia, and panic disorder in the general population.

The comorbidity of disorders and chronology of first symptoms of depression, agoraphobia, and panic disorder were investigated. The Diagnostic Interview Schedule was administered to 3258 household residents. Strong associations were shown among all three disorders. However, the comorbidity of agoraphobia and panic disorder seemed to be accounted for by the relationship of both disorders with depression. The mean age at appearance of first symptoms was earlier for agoraphobia (low teens) than for depression or panic disorder (both about age 20). The results do not support the view that panic disorder is an integral component of agoraphobia, but rather that it is more closely associated with depression. The fact that agoraphobia precedes depression casts doubt on the thesis that depression is primary to anxiety disorders. Interpretation should, however, be viewed with caution because of the retrospective nature of the diagnostic instrument.