MSc BLOG – Epilepsy in Childhood & ASD
April 16, 2018
Epilepsy in Childhood and the Risk of Autism Spectrum Disorder: MSc in EBHC dissertation
In my clinical practice, I follow many infants and children with epilepsy and rare seizure disorders. Over time, I often noted the development of symptoms and behaviours associated with Autism Spectrum Disorders (ASD) in these children. The evidence for these disorders largely focuses on the risks of developing epilepsy in those with ASD. Clinical commentaries, however, say little about the increased risk of ASD for individuals with epilepsy.
My time in the MSc in Evidence-Based Healthcare enlivened my desire to critically examine the evidence for this relationship and contribute to the understanding of these complex disorders. For my dissertation, I completed a systematic review and meta-analysis of epilepsy in childhood and the risk of autism spectrum disorder.
Epilepsy and ASD are complex, possibly related disorders with a range of associated comorbidities and far reaching developmental consequences. Epilepsy is the most prevalent neurological condition among children younger than sixteen years of age and the second most commonly reported neurological condition in primary practice worldwide. As many as 1 in 26 people will develop epilepsy during their lifetime, and the incidence of epilepsy is highest in the first year of life. In the US, 1 in every 68 children, or up to 3.5 million individuals, is diagnosed with ASD. Currently, no cure exists for ASD, and individuals require supportive and therapeutic services, with considerable financial and societal costs. Individuals with ASD are at heightened risk of developing epilepsy, but consensus is lacking on whether childhood epilepsy increases the risk of ASD.
What did we do?
My systematic review, to my knowledge, is the first to examine the risk of ASD among individuals with epilepsy. We used standard review methods but also a novel statistical method estimating where the true effects are expected for 95% of studies that might be conducted over different settings and in future patients .
What did we find?
This systematic review found that individuals with epilepsy are at considerably greater risk of ASD than the general population (Odds ratio 11 to 12). When comorbid intellectual disability is present, the odds of ASD in epilepsy are seven times higher. Prediction intervals also suggest that future studies would find odds of ASD in epilepsy to be between 9 and 13 times greater than in those without epilepsy. Significantly, the odds of ASD found among individuals with epilepsy were twice as high as the odds of epilepsy among individuals with autism.
What do these results mean?
We identified the risk of ASD among individuals with one of the most common neurological disorders treated in clinical practice. Identifying correlates of risk in vulnerable populations is important to the development and refinement of surveillance systems and early identification of individuals at risk. Greater understanding of the relationship between epilepsy and ASD may allow their co-occurrence to be anticipated, facilitating earlier, more targeted screening and therapies that may improve the developmental outcomes and quality of life for affected individuals.
Early therapeutic intervention can significantly improve outcomes for individuals with both ASD and epilepsy. This review supports recommendations that ASD screening and developmental monitoring should be standard practice in all children with epilepsy, though this is currently not universal.
The review raises important questions about the possible mechanisms underlying both disorders. These are complex, remain elusive, and need further investigation. Future research into these mechanisms may be informed by the characteristics and shared risk highlighted in this review.
Dr. Arsenio Paez
Affiliations: I recently completed the MSc in Evidence-Based Health Care, and am now reading for the DPhil in EBHC. I am faculty in the Department of Physical Therapy, Movement and Rehabilitation Sciences at Northeastern University in Boston, MA, USA, and have a pediatric practice in New York, NY.