[Depressive onset episode of bipolar disorder: clinical and prognostic considerations]

Both retrospective and high-risk individuals prospective studies show that a high percentage of patients experience one or more depressive episodes previous the diagnosis of bipolar disorder. Depressive onset bipolar disorders begin earlier than the ones with a manic onset, have a higher duration, a chronic course with frequent recurrences, a depressive dominant polarity, a higher lifetime rate of suicidal behaviour, less psychotic symptoms and more rapid cycling. A relation between frequent rapid cycling and previous prescription of antidepressants was suggested but not rigorously demonstrated. Thus, a high percentage of patients presenting a first depressive episode will later develop bipolar disorder. Several risk factors of bipolarity have been identified and might be detected during each depressive episode by using standardised evaluations and family interviews, if necessary. Among them, an early age at first episode, frequent recurrences, a family history of bipolar disorder, atypical features and hypomanic symptoms are particularly associated with the subsequent development of a bipolar disorder. The impact of a high risk of bipolarity on drug prescription is unclear ; however, one can strongly recommend to intensifying clinical monitoring and to proposing adjunctive psychoeducation.