Taiwanese researchers have found for the first time a strong genetic association between schizophrenia and epilepsy.
Investigators discovered patients with epilepsy were nearly eight times more likely to develop schizophrenia and those with schizophrenia were close to six times more likely to develop epilepsy.
While a bidirectional relationship has been established between depression, mood disorder and epilepsy, the current study is the first to investigate this type of relation between schizophrenia and epilepsy.
The strong association between the diseases may be a result of genetic, environmental or neurobiological causes.
Using data from the Taiwan National Health Insurance database, the team identified 5,195 patients with schizophrenia and 11,527 patients with epilepsy who were diagnosed between 1999 and 2008.
The patient groups were compared to age and sex-matched controls. Researchers then analyzed the incidence and risk of developing epilepsy in the schizophrenia patient group and schizophrenia in the epilepsy cohort.
The findings showed that the incidence of epilepsy was nearly seven times that of normal in the schizophrenia patient group, and that the incidence of schizophrenia was three times that of normal among individuals diagnosed with epilepsy.
Researchers also reported that schizophrenia incidence was slightly higher in men with epilepsy than in women with the disease.
“Our research results show a strong bidirectional relation between schizophrenia and epilepsy,” said lead author I-Ching Chou, M.D. “This relationship may be due to common pathogenesis in these diseases such as genetic susceptibility and environmental factors, but further investigation of the pathological mechanisms are needed.”
The study is published in the journal Epilepsia.