PURPOSE: Schizophrenia and epilepsy may share a mutual susceptibility. This study examined the bidirectional relation between the two disorders. METHODS: We used claims data obtained from the Taiwan National Health Insurance database to conduct retrospective cohort analyses. Analysis 1 compared 5,195 patients with incident schizophrenia diagnosed in 1999-2008 with 20,776 controls without the disease randomly selected during the same period, frequency matched with sex and age. Analysis 2 comprised a similar method to compare 11,527 patients with newly diagnosed epilepsy with 46,032 randomly selected sex- and age-matched controls. At the end of 2008, analysis 1 measured the incidence and risk of developing epilepsy and analysis 2 measured the incidence and risk of developing schizophrenia. KEY FINDINGS: In analysis 1, the incidence of epilepsy was higher in the schizophrenia cohort than in the nonschizophrenia cohort (6.99 vs. 1.19 per 1,000 person-years) with an adjusted hazard ratio (aHR) of 5.88 [95% confidence interval (CI) 4.71-7.36] for schizophrenia patients. In analysis 2, the incidence of schizophrenia was higher in the epilepsy cohort than in the nonepilepsy comparison cohort (3.53 vs. 0.46 per 1,000 person-years) with an aHR of 7.65 (95% CI 6.04-9.69) for epilepsy patients. The effect of schizophrenia on subsequent epilepsy was greater for women, but the association between epilepsy and elevated incidence of schizophrenia was more pronounced in men. SIGNIFICANCE: We found a strong bidirectional relation between schizophrenia and epilepsy. These two conditions may share common causes. Further studies on the mechanism are required. Wiley Periodicals, Inc.
PURPOSE:Schizophrenia and epilepsy may share a mutual susceptibility. This study examined the bidirectional relation between the two disorders. METHODS: We used claims data obtained from the Taiwan National Health Insurance database to conduct retrospective cohort analyses. Analysis 1 compared 5,195 patients with incident schizophrenia diagnosed in 1999-2008 with 20,776 controls without the disease randomly selected during the same period, frequency matched with sex and age. Analysis 2 comprised a similar method to compare 11,527 patients with newly diagnosed epilepsy with 46,032 randomly selected sex- and age-matched controls. At the end of 2008, analysis 1 measured the incidence and risk of developing epilepsy and analysis 2 measured the incidence and risk of developing schizophrenia. KEY FINDINGS: In analysis 1, the incidence of epilepsy was higher in the schizophrenia cohort than in the nonschizophrenia cohort (6.99 vs. 1.19 per 1,000 person-years) with an adjusted hazard ratio (aHR) of 5.88 [95% confidence interval (CI) 4.71-7.36] for schizophreniapatients. In analysis 2, the incidence of schizophrenia was higher in the epilepsy cohort than in the nonepilepsy comparison cohort (3.53 vs. 0.46 per 1,000 person-years) with an aHR of 7.65 (95% CI 6.04-9.69) for epilepsypatients. The effect of schizophrenia on subsequent epilepsy was greater for women, but the association between epilepsy and elevated incidence of schizophrenia was more pronounced in men. SIGNIFICANCE: We found a strong bidirectional relation between schizophrenia and epilepsy. These two conditions may share common causes. Further studies on the mechanism are required. Wiley Periodicals, Inc.
Authors: Rosa Michaelis; Venus Tang; Janelle L Wagner; Avani C Modi; William Curt LaFrance; Laura H Goldstein; Tobias Lundgren; Markus Reuber Journal: Cochrane Database Syst Rev Date: 2017-10-27