Long-term outcome of bipolar I and II disorders

The Jorvi Bipolar Study (JoBS) is a collaborative bipolar research project between the Unit of Mental Health of the National Institute for Health and Welfare (former Department of Mental Health and Alcohol Research of the National Public Health Institute), Helsinki and the Department of Psychiatry, Jorvi Hospital (HUCH), Espoo, Finland. JoBS is a prospective, naturalistic cohort study of 191 secondary level care psychiatric in- and outpatients who at intake had a new episode of Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) bipolar disorder (BD). At intake, 1630 patients (aged 18-59 years) were screened using the Mood Disorder Questionnaire (MDQ) for a possible new episode of DSM-IV BD and 490 patients were interviewed using a semi-structured interview (the Structured Clinical Interview for DSM-IV Disorders, researcher version with Psychotic screen, SCID-I/P). An acute phase of DSM-IV BD was verified in 191 patients, who were included in the study cohort. Lifechart-methodology based on DSM-IV was used at baseline and in follow-up interviews at 6 months, 18 months, and 5 years to gather information on the course of the illness in the form of a graphic lifechart. Observer- and self-reported scales were used both at baseline and at follow-up assessments. The aim of this study was to investigate the 5-year outcome with regard to remission, recurrence, time spent ill, and suicide attempts, to assess the influence of the predominant polarity on outcome, and to test whether clinically relevant course characteristics or course classes from the first 18 months predict the long-term outcome. In this 5-year follow-up, BD patients spent about half of their time ill; almost one-third of the time in illness episodes and about one-sixth of the time with subthreshold symptoms. Contrary to earlier long-term studies, no difference was found between patients with BD I and BD II in time spent in depressive states. Almost all (96%) of the patients recovered from the index episode, but the majority (87%) had a recurrence in follow-up. Among patients with a depressive index phase, severity of depression, cluster C personality disorders, and lifetime psychotic symptoms predicted worse outcome. During the 5-year follow-up, 28% of the patients attempted suicide. More than half (57%) had at least one suicide attempt (SA) during their lifetime. The variations in incidences of SAs between the illness phases were remarkably large. The incidence was highest, over 120-fold that in euthymia, during mixed states, and also very high, almost 60-fold that in euthymia, in major depressive episodes (MDEs). During MDEs, duration and severity of depression and comorbid cluster C personality disorders predicted the risk. The variations in incidence rates exceed the potency of trait characteristics as risk factors, implying that the question of when is the risk highest, rather than who is at risk, might be more relevant when assessing suicide risk in BD. Reducing time spent in high-risk states is crucial for suicide prevention. Dimensional course characteristics established from the first 18 months of follow-up predicted outcomes over the subsequent follow-up period up to 5 years. The proportion of time depressed, the severity of depressive symptoms, and the proportion of time manic predicted more time spent ill in follow-up. The proportion of time manic, the severity of manic symptoms, and depression-to-mania switching predicted a greater likelihood of hospital admissions in follow-up. These dimensional descriptors of clinical course may be useful in predicting the long-term outcome of BD. About half (52%) of the patients had a predominant polarity when setting the threshold in at least two-thirds of lifetime episodes to be either manic or depressive polarity. For 16% of the patients, the predominant polarity was manic (MP), for 36% depressive (DP), and for 48% a predominant polarity could not be applied (no-polarity group, NP). However, the classification of predominant polarity was influenced by the time frame used. In the 5-year follow-up, the MP group spent significantly more time euthymic, less time in MDEs, and more time in manic states than the two other groups. The MP group had significantly lower incidence of SAs in follow-up and lower prevalence of lifetime comorbid anxiety disorders, but more lifetime psychotic symptoms. An association existed between the predominant polarity and the polarity of the first illness episode. Overall, according to this study, predominant polarity has predictive validity in the long-term course of BD. The MP group seemed to have a better prognosis than the two other groups, which resembled each other in many respects. According to this long-term follow-up study, most BD patients recovered from the index episode, but suffered from recurrent illness episodes. When depressed, not only the severity and duration of depression but also comorbid cluster C personality disorders and lifetime psychotic symptoms may indicate worse outcome. These risk factors and especially the high-risk states for suicidality should be recognized and intensively treated in clinical practice. Dimensional course descriptors and predominant polarity may be helpful in predicting outcome.