title: Epilepsy in autism: features and correlates.
abstract: BACKGROUND
  Epilepsy occurs in a significant minority of individuals with autism, but  few long-term follow-up studies have been reported, so the prevalence,  features (type of seizures, age at onset and severity, etc.) and correlates  (IQ history of regression, family history) have only partially been  identified.
  
  
  OBJECTIVE
  To undertake a long-term follow-up study of individuals with autism in  order to better characterise the features and correlates of epilepsy in  individuals with autism.
  
  
  METHODS
  One hundred and fifty individuals diagnosed with autism in childhood were  followed up when they were 21+ years of age. All individuals were screened for  a history of possible seizures by parental/informant questionnaire. An  epilepsy interview was undertaken and medical notes reviewed for individuals  with a history of possible seizures. The features and correlates of epilepsy  were examined using survival and regression analysis.
  
  
  RESULTS
  Epilepsy developed in 22% of participants. In the majority, seizures began  after 10 years of age. Generalised tonic-clonic seizures predominated  (88%). In over a half (19/33), seizures occurred weekly or less frequently and  in the majority of individuals (28/31) they were controlled with the  prescription of one to two anticonvulsants. Epilepsy was associated with  gender (female), intellectual disability and poorer verbal abilities. Although  the presence of epilepsy in the probands was not associated with an increased  risk of epilepsy in their relatives, it was associated with the presence of  the broader autism phenotype in relatives. This indicates that the familial  liability to autism was associated with the risk for epilepsy in the  proband.
  
  
  CONCLUSIONS
  Epilepsy is an important medical complication that develops in individuals  with autism. Seizures may first begin in adolescence or adulthood. Putative  risk factors for epilepsy in autism were identified and these will require  further investigation in future studies.
authors.affiliation: Department of Child & Adolescent Psychiatry and MRC Centre for Social Genetic & Developmental Psychiatry, Institute of Psychiatry, Kings College London, UK. Patrick.Bolton@kcl.ac.uk
authors.forename: Patrick F
authors.initials: PF
authors.lastname: Bolton
authors.forename: Iris
authors.initials: I
authors.lastname: Carcani-Rathwell
authors.forename: Jane
authors.initials: J
authors.lastname: Hutton
authors.forename: Sue
authors.initials: S
authors.lastname: Goode
authors.forename: Patricia
authors.initials: P
authors.lastname: Howlin
authors.forename: Michael
authors.initials: M
authors.lastname: Rutter
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D014150:Antipsychotic Agents / Q000627:therapeutic use; D001321:Autistic Disorder / Q000188:drug therapy / Q000453:epidemiology*; D002648:Child; D002675:Child, Preschool; D004827:Epilepsy / Q000188:drug therapy / Q000453:epidemiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D015995:Prevalence; D012307:Risk Factors; D012720:Severity of Illness Index; D016019:Survival Analysis; D055815:Young Adult
chemical_list: D014150:Antipsychotic Agents