Agoraphobia in adults: incidence and longitudinal relationship with panic

Background Theories regarding how spontaneous panic and agoraphobia relate are based mostly on cross-sectional and/or clinic data. Aims To determine how spontaneous panic and agoraphobia relate longitudinally, and to estimate the incidence rate of and other possible risk factors for first-onset agoraphobia, using a general population cohort. Method A sample of 1920 adults in east Baltimore were assessed in 1981-1982 and the mid- 1990s with the Diagnostic Interview Schedule (DIS). Psychiatrist diagnoses were made in a subset of the sample at follow-up (n=816). Results Forty- one new cases of DIS/ DSM -III - R agoraphobia were identified (about 2 per 1000 person-years at risk). As expected, baseline DIS/ DSM -III panic disorder predicted first incidence of agoraphobia (OR=12,95% CI 3.2-45), as did younger age, female gender and other phobias. Importantly, baseline agoraphobia without spontaneous panic attacks also predicted first incidence of panic disorder (OR=3.9,95% CI 1.8-8.4). Longitudinal relationships between panic disorder and psychiatrist- confirmed agoraphobia were strong (panic before agoraphobia OR=20,95% CI 2.3-180; agoraphobia before panic OR=16,95% CI 3.2-78). Conclusions The implied one-way causal relationship between spontaneous panic attacks and agoraphobia in DSM - IV appears incorrect. Declaration of interest None.