Interactions between seizure frequency, psychopathology, and severity of intellectual disability in a population with epilepsy and a learning disability.

Despite observations associating lower IQ and psychopathology in epilepsy, the possible differential effects of varying severity of learning (intellectual) disability (LD) on the manifestation of psychopathology in people with LD and epilepsy have not been clarified. In this study of retrospectively collected data describing the epilepsy, learning disability, and psychopathology of 175 patients with epilepsy and LD over a 3-month period, we observed that 65 patients had no recent seizures, whereas 110 had experienced at least one seizure in the preceding 3 months. We found that depression and psychoses were more common in those with no seizures in the preceding 3 months, but that which of these psychiatric states was manifest was related to the severity of LD. Psychosis rates were higher in those with mild LD, whereas depression rates were higher in those with severe LD.