Review Predicting the course and outcome of bipolar disorder: A review T. Treuer a , M. Tohen b, * a Area Medical Center Vienna, Eli Lilly & Company, 1075 Budapest, Madach u 13–14, Hungary b University of Texas Health Science Center, San Antonio, Texas 78229, USA 1. Introduction Prediction of the course and outcome of bipolar disorder (BD) continues to be challenging, despite recent observational studies conducted in North America and Western Europe. Although high diagnostic stability is typical for BD, a recent observational study showed a high prevalence of misdiagnosis and of diagnostic shifts from other psychiatric disorders to BD [59]. BD represents the full spectrum of mood disorders that are chronic and is a major methodological challenge for prediction of the outcome [32] and natural course of the disease [57,79]. The natural course of BD is characterized by a constant risk of recurrences over a patient’s life span, even 30 to 40 years after onset and up to 70 years of age or more, causing impairment of psychosocial functioning, despite the advances in pharmacological and non-pharmacological treatments [76,26]. The influence of modern treatment interventions on the natural course of illness is uncertain. While considered to have a more favorable prognosis than schizophrenia, it is not uncommon for BD to include persisting alterations of psychosocial functioning. Although long-term symptomatic remission does not guarantee functional recovery [4,68,73], it may have a favorable impact on overall prognosis. Observational long-term studies on patients with BD reported persistent impairment with significant disability, including 19% to 23% of months with moderate impairment and 7% to 9% of months with severe overall impairment [74]. Patients with BD I were unable to carry out work role functions during 30% of assessed months, which is significantly more in comparison to patients with unipolar major depression or BD II (21% and 20%, respectively). This degree of disability is similar to that of schizoaffective disorders [29]. Furthermore, neuropsycohlogical impairment due to BD persists during euthymic states, but is likely to be partially confounded by mild affective symptoms in remitted patients [42]. In view of the higher degree of treatment resistance in patients with BD, there is an alarming need to develop significant prognostic, diagnostic and treatment interventions to prevent the burden of this illness. This review article summarizes the main factors involved in predicting the course and outcome of BD. 1.1. Outcome after first episode The decade-long McLean-Harvard First Episode Project has systematically followed large numbers of patients from first hospitalization with bipolar or psychotic affective and non affective disorders, as defined in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV). This study indicates that, despite modern pharmacological treatments, the course and outcome of BD are not satisfactory. Full functional recovery is uncommon and full symptomatic recovery is much slower than syndromal recovery, with earliest morbidity being depressive-dysphoric. Initial depression or mixed-states predicted European Psychiatry 25 (2010) 328–333 ARTICLE INFO Article history: Received 4 September 2009 Received in revised form 2 November 2009 Accepted 9 November 2009 Available online 4 May 2010 Keywords: Bipolar disorder Outcome prediction Treatment ABSTRACT Despite of advances in pharmacological and non-pharmacological treatments, bipolar disorder often entails multiple relapses and impaired psychological functioning. The extent to which modern treatments have influenced the natural course of a mental disorder is uncertain. Prediction of the course and outcome of bipolar disorders continues to be challenging, despite the multiple research efforts worldwide. Due to a lack of laboratory diagnostic tests and biomarkers, psychiatric interview and examination provide the basis for outcome prediction. While considered to have more favorable prognosis than schizophrenia, it is not uncommon for bipolar disorder to include persisting alterations of psychosocial functioning. Although long-term symptomatic remission does not guarantee functional recovery, it may have a favorable impact on long-term overall prognosis. The high degree of treatment resistance in patients with bipolar disorder highlights the need to develop better identification of outcome predictors, prognosis and treatment intervention, designed to reverse or prevent this illness burden. This review summarizes the main factors involved in predicting the course and outcome of bipolar disorder. ß 2010 Elsevier Masson SAS. All rights reserved. * Corresponding author. Tel.: +1 210 567 5329; fax: +1 210 567 8570. E-mail address: tohen@uthscsa.edu (M. Tohen). 0924-9338/$ – see front matter ß 2010 Elsevier Masson SAS. All rights reserved. doi:10.1016/j.eurpsy.2009.11.012