Subtypes of panic attacks and ICD-9 classification.

No single ICD-9 category corresponds to panic disorder (DSM-III). To investigate whether patients with panic attacks can be identified by means of ICD-9, 97 patients with three panic attacks within 3 weeks were recruited from various medical centers, and were classified independently according to DSM-III and ICD-9. The ICD-9 diagnoses were scattered over a broad range of categories, and it was impossible to identify patients with panic disorder in this manner. Anxiety state, affective psychosis, and depressive neurosis were the most frequent ICD-9 diagnoses. The boundary between affective psychosis on the one hand and anxiety state and depressive neurosis on the other hand was validated by …