Manic episode in epilepsy and bipolar I disorder: a comparative analysis of 13 patients.

PURPOSE: To determine whether the manic episode of patients with epilepsy has different characteristics from manic episode of patients with bipolar disorder.
METHODS: Interictal manic episodes in patients with epilepsy (epilepsy group) were compared with mood disorders in patients with bipolar I disorder (bipolar group), as defined by the DSM-IV. There were 13 patients (five women and eight men) in each group.
RESULTS: Five epilepsy patients had relatives with epilepsy and/or convulsions, and four bipolar patients had relatives with mood disorders. In the epilepsy group, two had substance-related or organic factors associated with the episodes besides epilepsy, and two exhibited a postictal manic state that had the same symptoms as those of their interictal manic episodes. Ten patients of the epilepsy group had dependent-childish behavior. The epilepsy group had fewer severe mood episodes than the bipolar group. Ten epilepsy patients had fluctuating mood disturbances, and eight had rapid cycling of mood episodes. The epileptogenic zone was in the frontal and/or temporal lobes of eight patients and in multiple lobes of two others; it could not be localized in the three remaining patients.
CONCLUSIONS: The clinical features of the interictal manic episodes in the epilepsy group were different from those in the bipolar group. The manic episodes of the epilepsy group appeared heterogeneous in their causal factors. An epileptogenic zone in the frontal and temporal lobes seems to play an important role in the mood episodes of the majority of patients with epilepsy.