Time to remission and relapse after the first hospital admission in severe bipolar disorder

Few studies of the time to remission and first relapse in severe bipolar disorder have been based on epidemiologically defined samples or have examined patient characteristics and time-varying indicators of medication use simultaneously. Using a cohort from the Suffolk County Mental Health Project, we describe these temporal patterns and their relationships with childhood, illness, and treatment characteristics. A multi-facility cohort of 123 first-admission inpatients with DSM-IV bipolar disorder with psychotic features was followed for 4 years. Dates of the first complete remission (lasting at least 2 months), subsequent relapses, and use of antimanic (AM),antipsychotic (AP), and antidepressant (AD) medications were recorded. Childhood and illness characteristics were ascertained at baseline using standard instruments. By the 4-year point, 83.7% had achieved a full remission, with 42.3% remitting within 3 months, 63.4% within 6 months, and 74.8% within 1 year. Overall, younger age of onset, history of childhood psychopathology, and higher Brief Psychiatric Rating Scale (BPRS) anxiety/depression scores were significantly associated with longer time to remission. Discontinuing AM, AP and AD (compared to never using) and taking AP and AD (compared to never using) were significantly associated with remission in the multivariate analysis. Of the 103 participants with complete remission, 61.2% suffered a relapse; 24.3 % relapsed within 6 months of remission, and 35.9% within a year. Overall, 32.5% of the 123 participants had a single episode followed by full remission. Childhood internalizing-type problems, higher BPRS anxiety/depression and Hamilton depression scores, and an admission episode not involving mania, but not patterns of medication use, were associated with shorter time to relapse. By 4-year follow-up, the majority of severely ill bipolar patients had remitted from their initial episode, but more than half subsequently relapsed. Illness characteristics, especially depressive symptoms, and medication treatment were associated with the early course, although medication use after remission was not associated with relapse.