Predictors of Presurgical Evaluation Among Patients with Drug-resistant Epilepsy Using the Observational Medical Outcomes Partnership Common Data Model: Single-center Pilot Study

Introduction: Surgery is an underutilized treatment option for patients with drug-resistant epilepsy (DRE). There is a need for longitudinal, population-based studies that characterize barriers to comprehensive presurgical evaluation for patients with DRE.

Methods: We queried our center’s electronic health record derived Observational Medical Outcomes Partnership database for patients meeting a validated, highly specific phenotype for DRE between 1/1/2015 and 4/1/2020. The primary outcome, a proxy for evaluation, was completion of 3 categories of neurodiagnostic studies: ≥1 MRI brain (or other advanced imaging PET, SPECT, fMRI, or Wada), ≥1 inpatient video EEG, and ≥1 neuropsychological evaluation (i) between 2 years before and after the index date and (ii) any time preceding 4/1/2022. We performed logistic regression to identify factors associated with evaluation.

Results: 2,741 patients met the inclusion criteria for DRE; 393 (14.3%) completed evaluation within +/- 2 years and 696 (25.4%) all time. Neuropsychological testing was the least frequently completed study, performed in 526 (19.2%) +/- 2 years and 827 (30.2%) all time. Patients were less likely to complete evaluation if they had Hispanic or Latino ethnicity (OR 0.56, 95% CI 0.43-0.74, p< 0.0001) or generalized epilepsy (OR 0.21, 0.12-0.26, p< 0.0001). Patients were more likely to complete evaluation if they had ≥2 outpatient epilepsy visits in the preceding year (OR 7.95, 4.32-14.65, p< 0.0001), ≥1 inpatient visit (OR 3.59, 2.81-4.58, p< 0.0001), or age 20-39 years (OR 1.67, 1.28-2.19, p< 0.0001).

Conclusion : The rate of comprehensive evaluation among patients with probable DRE at our center exceeds national estimates of < 2%, but fewer than a third of potentially eligible patients complete the necessary studies. More frequent epilepsy visits and access to neuropsychological testing may be proximate steps towards comprehensive evaluation. There is a particular need among Hispanic or Latino populations, as well as children and older adults.