Abstracts

Rationale: The RNS System is a cranially implanted brain-responsive neurostimulation system that directly stimulates seizure foci to help control focal-onset seizures. There have been landmark studies on the efficacy and safety of the RNS System (1,4). Significant improvements in quality of life in epilepsy (QOLIE) were observed in patients with the RNS System during the RNS clinical trials (2,3). This is a retrospective self-controlled study of QOLIE for patients with RNS treated at Southern Kaiser Permanente during the COVID pandemic.

Methods: Our data was collected between 2020-2021. There were 10 adult patients implanted with the RNS System at Southern Kaiser Permanente. Among them, there was one patient whose RNS was never turned on, therefore, was excluded from the study.

A 31-item QOLIE questionnaire was administered in-person or by telephone. QOLIE-31 scores were compared from before the RNS placement and at the time of the interview.

The impact of event scale (IES) was also included to evaluate the impact of the ongoing pandemic.

All the patients underwent epilepsy presurgical evaluation prior to the RNS placement, including EEGs, MRI Brain, PET CT, MEG, and neuropsychiatric evaluations.

Results: The total QOLIE scores improved in all 9 patients at the time of interview compared to those before RNS implantation (on average, from 37.6 to 59.4, P=0.00901). Each subscore on average also had consistent and statistically significant improvement after RNS placement, including the seizure worry (2.01 to 4.81, P=0.0139), emotional wellbeing (7.33 to 10.9, P=0.0572), the overall quality of life (5.34 to 10.2, P=0.00380), and energy (3.80 to 7.07, P=0.0168).

Most QOLIE subscores improved for each individual patient except for patient 8. Patient 8 had a significantly decreased subscore in social function and unchanged subscores in emotional wellbeing, medication effect, and cognition. This patient also had the highest IES score at 45, and experienced severe life impact from the pandemic, which may have accounted for his subscores. Nonetheless, the rest of 8 patients’ IES scores fell in the range of mild to moderate impact of the pandemic.

Conclusions: The RNS System improved patient’s quality of life, despite the global COVID pandemic. Potential recall bias and small sample size were discussed which may direct future research.

Funding: Please list any funding that was received in support of this abstract.: No sources of funding. No disclosures.

REFERENCES

1. Heck CN, 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 Mar;55(3):432-41.

2. Loring DW, et al. Mood and quality of life in patients treated with brain-responsive neurostimulation: The value of earlier intervention. Epilepsy Behav. 2021 Apr;117:107868.

3. Meador KJ, et al. Quality of life and mood in patients with medically intractable epilepsy treated with targeted responsive neurostimulation. Epilepsy Behav. 2015 Apr;45:242-7.

4. Nair DR, et al. Nine-year prospective efficacy and safety of brain-responsive neurostimulation for focal epilepsy. Neurology. 2020 Sep 1;95(9):e1244-e1256.