Abstracts

Rationale: In addition to seizures, school-aged children with epilepsy can have co-existing cognitive and behavioural difficulties but the spectrum and prevalence of such difficulties is uncertain. Thus, the aim of the Children with Epilepsy in Sussex Schools (CHESS) study was to combine the use of standardised measures of cognition and behaviour to determine the prevalence of clinical diagnoses of common comorbid neurobehavioral conditions and factors associated with such diagnoses in school-aged children with active epilepsy. Methods: 85 (74% of eligible population in a defined geographical region in the UK) school-aged children (4-15 years) with active epilepsy (on one or more Anti Epileptic Drug (AED) and/or had a seizure in the last 12 months) underwent comprehensive psychological assessment in 2011/2012. The assessment protocol included measures of global and specific aspects of cognition, and screening measures for Autism Spectrum Disorder (ASD), Attention Deficit Hyperactivity Disorder (ADHD), Developmental Coordination Disorder (DCD), Depression and Anxiety. Consensus neurobehavioral diagnoses were made with respect to DSM-IV criteria by a child psychologist, child and adolescent psychiatrist and paediatrician. Factors associated with intellectual disability and behavioural disorders in this population were analysed using logistic regression. Results: 41% of the children were functioning within the Intellectually Disabled (ID) (IQ<70) range and 54% had an IQ score 1SD below average (IQ<85). 60% of children met consensus diagnostic criteria for at least one DSM-IV behavioural disorder (see Table 1 for individual disorders). Only 20% of children had previously been diagnosed with a DSM-IV disorder. The group mean score on the Processing Speed Index of the Wechsler tests was significantly below assessed IQ (p<.01) and mean score on the coding subtest was significantly below all of the other Wechsler subtests based on paired t-test comparisons (p<.05). Almost 80% of children with active epilepsy had a DSM-IV disorder and/or cognitive impairment (IQ< 85). Logistic regression revealed that seizures in the first 24 months of life, being on more than one AED (OR 5.9, 95% CI 1.7-20.6) and having experienced tonic-clonic seizures (OR 6.4, 95% CI 2.1-52.0) were all independently associated with IQ<70 (see Table 2). None of the epilepsy related factors (i.e., age of first seizure, duration of epilepsy, seizure frequency, being on more than one AED, seizure type) independently predicted the presence of ADHD, DCD or an anxiety disorder. Conclusions: A very high proportion of school-aged children with active epilepsy had cognitive and behavioural problems. Two-thirds of children who met DSM-IV criteria for a behavioural disorder had not previously been diagnosed. Some epilepsy related factors were significantly associated with intellectual disability but, in the main, were not associated with behavioural disorders.