Mixed depressive features predict maniform switch during treatment of depression in bipolar I disorder

Case observations imply that depressed patients with mixed features are of high risk for maniform switch during acute treatment.

The medical records of 158 bipolar I depressives were examined with respect to mixed depressive features at admission, naturalistic medications, and maniform switch during inpatient treatment.

Besides pharmacological variables, the number of mixed depressive symptoms (flight of ideas, racing thoughts, logorrhea, aggression, excessive social contact, increased drive, irritability, and distractibility) at admission was associated with a higher risk for, and the acceleration of, maniform switch during inpatient treatment.

This was a retrospective study in patients receiving naturalistic treatment. The cohort was hospital based and thus not representative of the full range of bipolar affective disorder.

In line with recent studies, our results underline the factors inherent in subjects at a higher risk of switch. Investigation of the relationships between several inherent factors and their interactions with pharmacological treatments may be important in resolving the controversy surrounding antidepressant-induced mania. Further validation studies on mixed depression are warranted.