Prevalence of interictal psychiatric disorders in patients with refractory temporal and extratemporal lobe epilepsy in Spain. A comparative study

We aim to investigate whether temporal origin of epilepsy increases the risk of developing a psychiatric disorder and more specifically a major depressive disorder. The lack of standardized diagnostic instruments and the methodologic differences between studies highlight the fact that this issue warrants further, systematic, study. Three-hundred eight patients with complex partial seizures were classified according to temporal or extratemporal origin, following the Commission on Classification and Terminology of the International League Against Epilepsy (ILAE), 1989 localization-related concept. All patients were assessed using the Structured Interview for DSM-IV axis I psychiatric disorders (SCID-I). Lifetime and previous-year prevalence of psychiatric disorders were compared in temporal and extratemporal subgroups, using multivariate analysis. Previous-year major depression was significantly associated with temporal lobe origin. Our results do not support the hypothesis that patients with temporal lobe epilepsy (TLE) have more psychiatric illness in general, although they do suggest a specific connection between TLE and major depression.