Heterogeneity of prior admission history among patients with bipolar disorder

Background: Patients on a first admission for bipolar disorder often have a history of other psychiatric diagnoses for previous admissions. Aims: The current study examines the time course and diagnoses of psychiatric admissions prior and subsequent to a first hospitalisation for a diagnosis of bipolar disorder. Method: The prior admission histories (over the period 1965–1989) of 1167 patients who had been hospitalised in state mental health facilities with their first admission with diagnosis of bipolar disorder between 1983 and 1989 were examined. Results: A total of 542 (46.4%) patients had at least one previous hospitalisation with a psychiatric diagnosis other than bipolar disorder. Two prominent groups emerged; one group which had primarily a history of prior admissions with diagnoses of depression over 1–3 years, and a second which mainly had previous admissions for schizophrenia, over a period longer than for those with a primarily depressive history. The group with a history of schizophrenia was significantly younger and had a greater number of admissions prior to the first bipolar disorder diagnosis than the depression group. Limitations: This was a record-based study which did not examine cases which were not hospitalised. Conclusions: There appeared to be three distinct patterns of prior presentations in those patients admitted with a diagnosis of bipolar disorder.