The Importance of Subsyndromal Symptoms in Bipolar Disorder

Bipolar disorder continues to be characterized by poor clinical and functional outcomes in manypatients. Poor outcomes may be related to subsyndromal symptoms, defined as symptoms that fail tomeet the full diagnostic criteria for a mood episode. Several recent studies indicate that subsyndromalsymptoms in bipolar disorder are strongly associated with deficits in both social and occupationalfunctioning. Furthermore, subsyndromal symptoms appear to increase the risk of relapse. Combined,these factors emphasize the importance of aggressive treatment strategies at the onset of subsyndromalsymptoms. In addition, the use of subsyndromal symptoms to broaden the diagnostic criteriafor bipolar disorder is receiving increased attention. This article reviews and discusses these importantissues.