Psychiatric comorbidity in DSM-III-R hypochondriasis.

Forty-two DSM-III-R hypochondriacs from a general medical clinic were compared with a random sample of 76 outpatients from the same setting. Patients completed a research battery that included a structured diagnostic interview (Diagnostic Interview Schedule) and self-report questionnaires to measure personality disorder caseness, functional impairment, and hypochondriacal symptoms. Psychiatric morbidity in the hypochondriacal sample significantly exceeded that of the comparison sample. Hypochondriacs had twice as many lifetime Axis I diagnoses, twice as many Diagnostic Interview Schedule symptoms, and three times the level of personality disorder caseness as the comparison group. Of the hypochondriacal sample, 88% had one or more additional Axis I disorders, the overlap being greatest with depressive and anxiety disorders. One fifth of the hypochondriacs had somatization disorder, but the two conditions appeared to be phenomenologically distinct. Hypochondriacal patients with coexisting anxiety and/or depressive disorder (secondary hypochondriasis) did not differ greatly from hypochondriacal patients without these comorbid conditions (primary hypochondriasis). Because the nature of hypochondriasis remains unclear and requires further study, we suggest that its nosologic status not be altered in DSM-IV.