Association between epilepsy and systemic autoimmune diseases: A meta-analysis

PURPOSE To investigate the association between systemic autoimmune diseases (SAD) and epilepsy and to determine whether the strength of this association is increased in the young. METHODS A meta-analysis was done, analyzing the association between epilepsy and SAD using the available data in Medline and Embase through February 2016. We followed the recommendations of the PRISMA (preferred reporting items for systematic reviews and meta-analyses) statement and the MOOSE (meta-analysis of observational studies in epidemiology) guidelines. RESULTS A total of twenty-five studies met the inclusion criteria for this meta-analysis, which included 10,972 patients with epilepsy (PWE) and 2,618,637 patients with SAD. The PWE cohort was shown to have more than a 2.5-fold increased risk of SAD. The patients with SAD were also shown to have a more than 2.5-fold increased risk of epilepsy. The results indicated that patients <20 years of age had a 3-fold increased risk of SAD and epilepsy (OR=3.04 [95% CI 1.27-7.27], P=0.01; OR=3.15 [95% CI 1.92-5.15], P<0.01; respectively), and these risks were shown to be higher than patients >20 years of age. The PWE cohort had a 2.6-fold increased risk of celiac disease (OR=2.65 [95% CI 1.41-4.97], P<0.01). The patients with systemic lupus erythematosus had a 4.5-fold increased risk of epilepsy (OR=4.57 [95% CI 2.40-8.67], P<0.01). CONCLUSIONS There is an association between epilepsy and SAD, which was shown to be stronger at a young age.