How Much Does Bipolar II Depression Differ from Unipolar Depression?

Discriminating between bipolar II depression and unipolar depression matters a great deal because their appropriate treatment often differs. Yet, historical details that might differentiate the conditions are sometimes unknown, and phenomenological distinctions can be difficult to discern. In an effort to distinguish the phenotypes of bipolar II and unipolar depressions, investigators examined 32 depressive symptoms as rated by 394 depressed patients who were diagnosed with bipolar II disorder (n=119) or unipolar depressive disorder (n=275; 104 with melancholic features).

Sex and symptom severity did not differ between the three groups, but the melancholic subgroup was significantly older. Only perceived slower cognition and less need to be …