Abstracts

Rationale: Attention-Deficit/Hyperactivity Disorder (ADHD) has a high prevalence in children with epilepsy, particularly those with severe epilepsy treated at tertiary care centres. At the same time, many of these children have global developmental delays and/or cognitive disabilities that complicate accurate detection and diagnosis of ADHD. The goal of this study was to determine the prevalence and nature of ADHD in children with developmental disability and epilepsy, identify neurological predictors of ADHD symptoms in this population, and determine associations with quality of life. Methods: Eighty-five children with developmental disability and intractable epilepsy with scores of <70 on an adaptive behavior scale (SIB-R) were identified from a tertiary care centre, with mean age of 12.3 (SD = 3.9) and median age at seizure onset of 1.5 years (male:female = 46:39). ADHD symptom severity was measured with the ADHD-IV Rating Scale and quality of life with the Impact of Childhood Epilepsy scale. Results: About 20% of children had a normal behavioral profile with neither inattention nor hyperactivity on parent report (ADHD-RS-IV); 30% had elevations on inattention only, and 50% had elevations on both inattention and hyperactivity-impulsivity. Severity of ADHD was not related to severity of developmental disability, nor to the following epilepsy-related variables: age at onset, duration, seizure frequency, number of AEDs, number of failed AEDs. However, generalized epilepsy was related to worse ADHD symptoms. Severity of ADHD symptoms correlated with worse quality of life. Conclusions: ADHD symptoms of inattention and hyperactivity-impulsivity are not necessarily found in developmental disability occurring in epilepsy. However, a majority of developmentally disabled children with epilepsy may present with inattention or a combined inattention and hyperactivity-impulsivity profile, at a rate higher than previously published rates in epilepsy patients without developmental disability. Notably, there is variability in both the likelihood and nature of ADHD symptoms in children with developmental disability and epilepsy, but ADHD in this context is a marker for poor quality of life.