Abstracts

Rationale: Despite evidence of the benefits of pediatric epilepsy surgery, a substantial proportion of children with medically intractable epilepsy fail to receive this care in a timely manner. We examined the relative contribution of clinical, diagnostic and sociodemographic factors with time to resective surgery in a large cohort of children over the past 25 years. Methods: Clinical (age of onset, mean 2.5 years); seizure frequency, (79.4% ≥ daily seizures); history of infantile spasms, (33.5%); etiology, (51.2% neurodevelopmental); diagnostic (magnetic resonance imaging (MRI) prior to referral, 76.0%) and sociodemographic (gender, male 53%; race/ethnicity, 76.9% non-Hispanic white, 19.2% Hispanic; 78.3% private insurance) data were retrospectively abstracted from medical records of 430 children who had resective epilepsy surgery at UCLA (<18 years at time of surgery) from 1986 to 2010. Multivariable Cox proportional hazards models were used to measure the association of clinical, diagnostic and sociodemographic variables with ‘time to surgery' (age of onset to age of surgery, years; mean 4.5 years, SD=3.9) controlling for year of surgery. Results: In multivariate analysis, older age of epilepsy onset (HR 1.09; 95% CI 1.05-1.14); active (HR 5.67; 95% CI 3.74-8.60) and successfully treated infantile spasms (HR 2.20; 95% CI 1.63-2.96); daily seizures (HR 2.09; 95% CI 1.58-2.76); MRI prior to referral (HR 1.95; 95% CI 1.47-2.58); Hispanic ethnicity (HR 1.38; 95% CI 1.01-1.87); and private insurance (HR 1.54; 95% CI 1.14-2.09) (vs. Medicaid) were significantly associated with a shorter ‘time to surgery' (Table 1; p<0.04). There were significant race-insurance group differences in ‘time to surgery' (Log-rank p=0.049) with shortest ‘time to surgery' amongst those of Hispanic ethnicity with private insurance (Figure 1). Conclusions: While shorter time to pediatric resective epilepsy surgery is most strongly associated with greater disease severity (history of infantile spasms, daily seizures) and older age at epilepsy onset, other non-clinical diagnostic and sociodemographic factors also play a role. The finding that having an MRI prior to referral shortened time to surgery may reflect unmeasured factors such as referring physician and parent knowledge and advocacy. Furthermore, the observation that Hispanic (vs. non-Hispanic white) children with private insurance experienced a shorter time to surgery was unanticipated and warrants further investigation, but may reflect regional race/ethnicity differences and outreach efforts. Identifying the clinical and non-clinical impediments to timely surgery is important for developing interventions designed to improve access and outcomes.