Rationale: Epilepsy surgical management with responsive neurostimulation (RNS, Neuropace ©) involves regular downloading of electrocorticography data, which is then uploaded to a secure server for analysis by the epileptologist. The influence of patient factors such as patient adherence, reliability in downloading RNS data, and socioeconomic barriers on patient outcomes remains unknown. To address this gap, we aimed to identify barriers that affect patient outcomes in a diverse patient cohort in Baltimore, Maryland who underwent RNS placement.
Methods: We conducted a retrospective review of patients with medically refractory epilepsy who underwent surgical evaluation at our Level IV Epilepsy Center between February 2017 and January 2023. Patients with an active RNS implantation were included. Data collected included patient demographics, epilepsy history and evaluation, seizure outcomes, and social determinants of health. Median household income was collected using the Agency for Healthcare Research and Quality data. RNS download frequency was used as a surrogate marker for compliance and was obtained from the RNS patient data management system (PDMS) event list. The number of downloads was then categorized into the following groups: Daily (at least once per day), Weekly (one to six times per week), Monthly (one to three times per month), Quarterly (< 1 time per month). Seizure reduction outcomes were reported in quartiles during each clinical visit. A responder was defined as having a 50% or greater reduction in seizure frequency.
Results:
There were 17 patients evaluated. Mean age was 34 years (range 23-58), mean duration of implant was 4.0 years (SD 2.0), 7/17 (41%) were female, 3/17 (18%) were black, and 5/17 (29%) had a low median household income. There were 4/17 (24%) who did not graduate high school, 4/17 (24%) who completed high school, and 3/17 (18%) with a college degree or higher. Testing demonstrated 10/17 (59%) with low FSIQ (less than 25th percentile). At the most recent visit, upload frequency: 8/17 (47%) daily (as recommended), 4/17 (24%) weekly, 3/17 (18%) monthly, and 2/17 (12%) quarterly. At one and two years post implant, 7/15 (47%) and 6/12 (50%) patients achieved greater than 50% seizure reduction frequency, respectively. At the most recent visit, 15/17 (88%) patients achieved greater than 50% seizure reduction frequency and 14/17 (82%) reported seizure severity of better or much better.
Conclusions: Our patient cohort represents an urban and underserved community with several barriers to medical care. Despite these barriers, our patients have had good seizure response with RNS therapy that is consistent with reported literature.
1 Our group has implemented additional educational and social interventions in our clinic to further aid in overcoming these barriers. Social, educational, and compliance concerns should not deter consideration for RNS or other surgery in medically refractory epilepsy patients.
1 Heck CN, King-Stephens D, Massey AD, et al. Two-year seizure reduction in adults with medically intractable partial onset epilepsy treated with responsive neurostimulation: final results of the RNS System Pivotal trial. Epilepsia. 2014;55(3):432-441.
Funding: None