Prevalence and risk factors for autism spectrum disorder in epilepsy: a systematic review and meta‐analysis

<jats:sec><jats:title>Aim</jats:title><jats:p>To assess the prevalence and risk factors for autism spectrum disorder (<jats:styled-content style="fixed-case">ASD</jats:styled-content>) in epilepsy, and to better understand the relationship and comorbidity between these disorders.</jats:p></jats:sec><jats:sec><jats:title>Method</jats:title><jats:p>Psych<jats:styled-content style="fixed-case">INFO</jats:styled-content> and PubMed were searched for articles published in the past 15 years that examined the prevalence of <jats:styled-content style="fixed-case">ASD</jats:styled-content> in individuals with epilepsy.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>A total of 19 studies were found with a pooled <jats:styled-content style="fixed-case">ASD</jats:styled-content> prevalence of 6.3% in epilepsy. When divided by type, the risks of <jats:styled-content style="fixed-case">ASD</jats:styled-content> for general epilepsy, infantile spasms, focal seizures, and Dravet syndrome were 4.7%, 19.9%, 41.9%, and 47.4% respectively. Studies with populations under 18 years showed a 13.2 times greater risk of <jats:styled-content style="fixed-case">ASD</jats:styled-content> than study populations over 18 years, and samples with most (>50%) individuals with intellectual disability showed a greater risk 4.9 times higher than study populations with a minority of individuals with intellectual disability. The main risk factors for <jats:styled-content style="fixed-case">ASD</jats:styled-content> reported in the 19 studies included presence of intellectual disability, sex, age, and symptomatic aetiology of epilepsy.</jats:p></jats:sec><jats:sec><jats:title>Interpretation</jats:title><jats:p>Current research supports a high prevalence of <jats:styled-content style="fixed-case">ASD</jats:styled-content> in epilepsy. This study helps to define the clinical profile of patients with epilepsy who are at risk for <jats:styled-content style="fixed-case">ASD</jats:styled-content>, which may help clinicians in early screening and diagnosis of <jats:styled-content style="fixed-case">ASD</jats:styled-content> in this population.</jats:p></jats:sec><jats:sec><jats:title>What this paper adds</jats:title><jats:p> <jats:list list-type="bullet"> <jats:list-item><jats:p>Critical evaluation of previous studies examining the prevalence of autism spectrum disorder (ASD) in individuals with epilepsy.</jats:p></jats:list-item> <jats:list-item><jats:p>A meta‐analysis of 19 studies showed a pooled ASD prevalence of 6.3% in individuals with epilepsy.</jats:p></jats:list-item> <jats:list-item><jats:p>Studies that included a majority of individuals with intellectual disability or younger population age had a higher prevalence of autism.</jats:p></jats:list-item> <jats:list-item><jats:p>Risk factors reported in studies included presence of intellectual disability, sex, age, and symptomatic epilepsy origin.</jats:p></jats:list-item> </jats:list> </jats:p></jats:sec>