title: Population-level evidence for an autoimmune etiology of epilepsy.
abstract: OBJECTIVE
  Epilepsy is a debilitating condition, often with neither a known etiology nor an effective treatment. Autoimmune mechanisms have been increasingly identified.
  
  
  OBJECTIVE
  To conduct a population-level study investigating the relationship between epilepsy and several common autoimmune diseases.
  
  
  METHODS
  A retrospective population-based study using claims from a nationwide employer-provided health insurance plan in the United States. Participants were beneficiaries enrolled between 1999 and 2006 (N = 2 518 034).
  
  
  METHODS
  We examined the relationship between epilepsy and 12 autoimmune diseases: type 1 diabetes mellitus, psoriasis, rheumatoid arthritis, Graves disease, Hashimoto thyroiditis, Crohn disease, ulcerative colitis, systemic lupus erythematosus, antiphospholipid syndrome, Sjögren syndrome, myasthenia gravis, and celiac disease.
  
  
  RESULTS
  The risk of epilepsy was significantly heightened among patients with autoimmune diseases (odds ratio, 3.8; 95% CI, 3.6-4.0; P < .001) and was especially pronounced in children (5.2; 4.1-6.5; P < .001). Elevated risk was consistently observed across all 12 autoimmune diseases.
  
  
  CONCLUSIONS
  Epilepsy and autoimmune disease frequently co-occur; patients with either condition should undergo surveillance for the other. The potential role of autoimmunity must be given due consideration in epilepsy so that we are not overlooking a treatable cause.
authors.affiliation: Australian Institute of Health Innovation, University of New South Wales, Sydney, Australia2Children's Hospital Informatics Program at Harvard-Massachusetts Institute of Technology Health Sciences and Technology, Boston Children's Hospital, Boston, Massac.
authors.forename: Mei-Sing
authors.initials: MS
authors.lastname: Ong
authors.affiliation: Children's Hospital Informatics Program at Harvard-Massachusetts Institute of Technology Health Sciences and Technology, Boston Children's Hospital, Boston, Massachusetts3Center for Biomedical Informatics, Harvard Medical School, Boston, Massachusetts.
authors.forename: Isaac S
authors.initials: IS
authors.lastname: Kohane
authors.affiliation: Department of Biostatics, Harvard School of Public Health, Boston, Massachusetts.
authors.forename: Tianxi
authors.initials: T
authors.lastname: Cai
authors.affiliation: Center for Biomedical Informatics, Harvard Medical School, Boston, Massachusetts5Department of Neurology, Boston Children's Hospital, Boston, Massachusetts.
authors.forename: Mark P
authors.initials: MP
authors.lastname: Gorman
authors.affiliation: Children's Hospital Informatics Program at Harvard-Massachusetts Institute of Technology Health Sciences and Technology, Boston Children's Hospital, Boston, Massachusetts3Center for Biomedical Informatics, Harvard Medical School, Boston, Massachusetts.
authors.forename: Kenneth D
authors.initials: KD
authors.lastname: Mandl
mesh_terms: D000293:Adolescent; D000328:Adult; D001327:Autoimmune Diseases / Q000175:diagnosis* / Q000453:epidemiology*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D004827:Epilepsy / Q000175:diagnosis* / Q000453:epidemiology*; D005500:Follow-Up Studies; D006801:Humans; D007344:Insurance Claim Reporting / Q000639:trends; D011159:Population Surveillance / Q000379:methods; D012189:Retrospective Studies; D014481:United States / Q000453:epidemiology; D055815:Young Adult