THE INFREQUENCY OF PURE CULTURE DIAGNOSES AMONG THE ANXIETY DISORDERS

Background: Anxiety disorders are known to commonly coexist in individ uals, both with other anxiety disorders and with mental disorders from other groupings, such as affective disorders. We questioned how frequ ently anxiety disorders actually occur in isolation, as ''pure culture s.'' Method: We examined diagnostic patterns among the 711 subjects en tered into a large, multicenter study of anxiety disorders, the Harvar d/Brown Anxiety Disorders Research Program (HARP), which focused on pa nic, agoraphobia, generalized anxiety disorder, and social phobias as ''index disorders'' required for intake. Results: We used various defi nitions for ''pure culture.'' By all definitions, subjects with ''pure culture'' represented a minority, especially in cases of generalized anxiety disorder and social phobia, where comorbidity was virtually ub iquitous. ''Pure culture'' status was associated with later onset of i llness and less chronicity. Conclusion: Future studies of anxiety diso rders should aim to document the extensive comorbidity, rather than el iminate it by restrictive diagnostic exclusion criteria; lest they yie ld atypical or even misrepresented groups of patients. Clinicians shou ld not stop at identifying only the ''main'' diagnosis but look for ot her, comorbid diagnoses that are often present.