Our objective was to assess epilepsy surgery outcomes in older adults with drug-resistant epilepsy (DRE) and examine how clinical factors may be associated with seizure freedom 1 year following surgical treatment.
Approximately 1 in 3 people with epilepsy are resistant to pharmacological therapy and therefore candidates for surgical evaluation. Epilepsy surgery is thought to be underused in older adults, a population with an increased prevalence of seizures, although recent literature suggests that surgical outcomes may be comparable to younger populations.
A retrospective cohort study was conducted of patients aged > 55 years with DRE who underwent epilepsy surgery between 2016 and 2023 within the Mount Sinai Health System. Interventions included resection, laser interstitial thermal therapy (LITT), and neuromodulation: vagus nerve stimulation (VNS) and responsive neurostimulation (RNS). Surgical efficacy was classified one year postoperatively using the Engel Surgical Outcome Scale. Engel Class I reflects freedom from disabling seizures. We built a multivariable logistic regression model in R to assess factors associated with seizure-freedom, including age, antiseizure medication burden, and prior epilepsy surgery.
This study included 43 patients (mean age 61.3 years at surgery). 24 patients (55.8%) achieved Engel Class I outcomes. There was a significant difference (p= 0.0024) in the number of failed medications between Engel I (3.17 ± 1.74) and non-Engel I patients (4.89 ± 1.73). In our multivariable model accounting for age at seizure onset and prior epilepsy surgery, fewer failed medications was associated with an increased likelihood of seizure freedom at 1 year (OR= 0.586, 95% CI= 0.34-0.916, p= 0.031).
Our findings support the effectiveness of neurosurgical treatment for DRE in older adults, with over half of the patients achieving an Engel I outcome. The association between quantity of failed medications and seizure freedom may suggest the importance of early surgical evaluation and intervention in the aging population.