Longitudinal course of bipolar I disorder☆

Abstract 

The course of bipolar I disorder is characterized by frequently fluctuating levels of manic and depressive symptoms. In the current study, we sought to characterize the month-by- month course of this disorder in 61 patients who were originally enrolled in a clinical trial and were followed for a mean of 23.7 months (SD = 6.1). All patients in the trial received medication management; some received family psychosocial interventions as well. On a monthly basis, we assessed symptom severity using the Modified Hamilton Rating Scale for Depression (MHRSD) and the Bech-Rafaelson Mania Scale (BRMS). Each month, we categorized each participant as fully symptomatic, partially symptomatic, or asymptomatic in terms of both depressed and manic symptoms. We found that the median percent time fully symptomatic was 8%, the median percent time partially symptomatic was 22%, and the median percent time asymptomatic was 59%. Using DSM-IV-TR criteria for defining an acute mood episode, we found that the median length of episode was 1 month, and participants experienced, on average, one episode every 8 months. Estimates concerning percent time fully symptomatic and asymptomatic converge with those reported in other datasets.