Interictal depression in epilepsy

The relation between depression and epilepsy was evaluated in 96 epileptic out-patients. We found that 50% of epileptic patients fulfilled the DSM-IIIR criteria for depression. The Hamilton Rating Scale for Depression, the Beck Self Depression Inventory and the Zung Anxiety Scale were also used in all patients. The patients with partial seizures with complex semiology (CPS) were more depressed than the patients with primary generalized epilepsy and with partial seizures with elementary semiology. A significant increase in the level of anxiety was also found in the group with CPS compared to the other two groups. No correlations were noted between severity of depression and duration of epilepsy, seizure frequency, socio-economic status, education, and family history of depressive illness. No relationship was observed between anticonvulsant drug levels and depression. We failed to confirm an association between side of epileptic lesion and severity of depression. We suggest that depression in epileptic patients does not represent a psychological reaction to a particular cognitive or physical impairment, but is in some way related to the type of epilepsy.