A team of Canadian researchers, co-led by Dr. Elysa Widjaja and Dr. Mary Lou Smith, at the Hospital for Sick Children in Toronto, recently completed a cross-Canada study on the outcomes of epilepsy surgery on health-related quality of life in Canadian children.

Epilepsy can have terrible consequences on children’s health-related quality of life (HRQOL). Drug resistant epilepsy refers to poorly controlled seizures despite treatment with two or more anti-seizure medications. The two main treatments for drug resistant epilepsy are surgery or medical therapy. The motivation for assessing HRQOL after surgical and medical therapy was that epilepsy affects multiple aspects of children’s lives, and that parents of children with epilepsy are interested in knowing which treatment is effective not only in improving seizure control, but also their children’s HRQOL. The aims of the study were to compare the effectiveness of epilepsy surgery to medical therapy on improving HRQOL over 2 years, to understand which clinical, parent and family factors can influence the changes in HRQOL following treatment, and to identify the pre-operative factors that can predict HRQOL at 2 years after surgery.

How did the investigators do the study?
This multi-center study recruited children with drug resistant epilepsy treated with epilepsy surgery or medical therapy from eight centers in Canada, including the Hospital for Sick Children in Toronto, BC Children’s Hospital in Vancouver, Alberta Children’s Hospital in Calgary, CHU Ste-Justine in Montreal, The Children’s Hospital in Winnipeg, Royal University Hospital in Saskatoon, McMaster Children’s Hospital in Hamilton and London Health Sciences Centre in London. All children who had suspected focal epilepsy and were being evaluated for epilepsy surgery were eligible for the study. The medical therapy group consisted of children who, after undergoing a standard evaluation for epilepsy surgery, were found not to be candidates for surgery.

What did they measure?
The investigators asked parents to complete questions on their children’s HRQOL outcome and seizure frequency at baseline (time of surgical evaluation), and at 6-month, 1-year, and 2-year follow-ups.
The information on the children’s epilepsy was collected from medical records. Child and parent depressive and anxiety symptoms, as well as family functioning including satisfaction with family relationships, availability of family resources and family demands, were assessed with questionnaires at baseline, 6-month, 1-year and 2-year follow-up. The study also collected information on parents’ demographics including age, sex, employment status, household income, education, and marital status.

What did they find?
Of the 479 children eligible for the study, 265 participated. There were 111 surgical and 154 medical patients. The investigators found that surgical patients experienced significantly greater HRQOL improvement compared to medical patients. They tracked the changes in HRQOL over time and found that the largest improvement in HRQOL among surgical patients occurred in the first six months after surgery. However, HRQOL continued to improve in the first year after surgery, and thereafter remained stable at two years after surgery. Among medical patients, HRQOL remained relatively unchanged over the 2-year follow-up. Social functioning showed improvement after surgery, but cognitive, emotional and physical functioning did not improve after surgery. At the 2-year follow-up, twice as many surgical patients were seizure-free compared to medical patients (72% vs. 33% respectively). Those who were seizure-free were more likely to experience higher HRQOL.
The investigators extended the above findings by examining the contribution of seizure control, child and parent depressive symptoms and the availability of family resources in determining HRQOL after treatment (surgery vs. medical therapy). They found that better HRQOL observed among surgical patients was because of the indirect effect of surgery on improving seizure freedom, which then improved HRQOL. Child and parent depressive symptoms and family resources did not affect the relationship between treatment and HRQOL. It was also shown that the effect of seizure control on HRQOL was not mediated by child or parent depressive symptoms nor family resources.
Building on previous findings, the investigators evaluated the pre-operative predictors of HRQOL 2 years after epilepsy surgery. They showed that among surgical patients, better pre-operative HRQOL and older age at seizure onset were associated with better HRQOL 2 years after surgery. The other clinical variables, parent demographics, parent mood and family factors such as family resources, family relationships and family demands, did not predict HRQOL 2 years after surgery.

Why are the findings important?
This is the largest study assessing the HRQOL after epilepsy surgery in children. The inclusion of surgical and medical patients from multiple centers ensures that the findings are applicable to children with drug resistant epilepsy across Canada. This study provided evidence on the effectiveness of epilepsy surgery in improving children’s HRQOL. Understanding how HRQOL changes after surgery compared to medical therapy is important in counselling children and parents and will help them in their decision regarding treatment options. It was demonstrated that seizure control is the key driver for improved HRQOL, but child and parent depressive symptoms and family resources were not important mediators. This finding highlights the importance of achieving seizure control to improve HRQOL. Improving seizure control and HRQOL in children is important, as this may have downstream effects such as better educational and vocational attainment. Further, pre-operative HRQOL was founds to be the most important predictor for HRQOL 2 years after surgery, highlighting the importance of optimizing pre-operative HRQOL to maximize HRQOL after surgery. Interventions to enhance social skills and self-esteem, and reduce emotional distress, such as counselling, peer-support or cognitive behavioural therapy, as well as increased physical activity in children, could possibly improve HRQOL pre-surgery.