Vagus nerve stimulation in epilepsy: Efficiency and safety of outpatient practice

Disparities in Access to Deep Brain Stimulation and Responsive Neurostimulation Approaches to Drug-Resistant Epilepsy

BACKGROUND

Epilepsy affects 1% to 2% of the global population, and those who are resistant to medical treatment may be candidates for neuromodulation. In select populations, brain stimulation approaches including deep brain stimulation (DBS) and responsive neurostimulation (RNS) are used. Although studies have shown that patients from Black, Hispanic, lower income, and rural communities have less access to epilepsy care and have lower rates of epilepsy surgery, disparities in the use of brain stimulation for epilepsy treatment are currently not known.

MATERIALS AND METHODS

We queried the US National Inpatient Sample data base from January 1, 2014 to December 31, 2019 for all patients discharged with an International Classification of Diseases (ICD) Ninth Revision or ICD Tenth Revision diagnosis of drug-resistant epilepsy. Among these patients discharged, the rates of brain stimulation treatment, including DBS and RNS, were reported in each subgroup of race, ethnicity, and insurance. To generate national estimates, all analyses were weighted.

RESULTS

A total of 237,895 patients discharged with drug-resistant epilepsy were identified, of whom 4,925 (2.1%) received brain stimulation treatment for drug-resistant epilepsy. Black patients (n = 420, 0.9%, odds ratio [OR] = 0.51, 95% CI [0.40, 0.64]) were less likely to receive brain stimulation treatment than were White patients (n = 3300, 2.4%). There was no significant difference between Asian (n = 105, 2.3%, OR = 0.80, 95% CI [0.53, 1.33]) and Hispanic (n = 655, 2.6%, OR = 0.95, 95% CI [0.77, 1.17]) patients and White patients. No significant difference was observed between female (n = 2515, 2.1%, OR = 1.02, 95% CI [0.89, 1.17]) and male (n = 2410, 2.0%) patients either. Patients with Medicare (n = 1150, 1.2%, OR = 0.69, 95% CI [0.57, 0.84]) or Medicaid (n = 1150, 1.8%, OR = 0.52, 95% CI [0.44, 0.62]) were less likely to receive brain stimulation treatment than were those with private insurance as the primary payer (n = 2370, 3.9%).

CONCLUSIONS

We discovered significant disparities in the use of brain stimulation treatments for drug-resistant epilepsy based on race and insurance status. More research will be required to determine the cause of these disparities.

Predictors of vagus nerve stimulation complications among pediatric patients with drug-resistant epilepsy

OBJECTIVE

Complications from vagus nerve stimulator (VNS) procedures are common and can have important implications for morbidity and seizure control, yet predictors of complications are poorly understood. The objective of this study was to assess clinical factors associated with minor and major complications from VNS procedures among pediatric patients with drug-resistant epilepsy.

METHODS

The authors performed an 11-year retrospective review of patients who underwent VNS procedures for drug-resistant epilepsy at age < 21 years. The primary outcome was complications (minor or major) following VNS surgery. Preoperative and surgery characteristics were compared between patients who developed versus those who did not develop complications. Multivariable Poisson regression was performed to determine the association between preoperative characteristics and infection.

RESULTS

Of 686 surgeries, 48 complications (7.0%) developed; there were 7 minor complications (1.0%) and 41 major complications (6.0%). Surgeries with minor complications were an average of 68 minutes longer than those without minor complications (p < 0.001). The incidence rate of infection was 1 per 100 person-years, with 3% of procedures complicated by infection. Poisson regression revealed that after adjusting for age at surgery, duration of surgery, and primarily motor seizure semiology, the incident rate of infection for revision surgeries preceded by ≥ 2 procedures was 19 times that of first-time revisions.

CONCLUSIONS

The overall minor complication rate was 1% and the overall major complication rate was 6% for VNS procedures. Longer surgery duration was associated with the development of minor complications but not major complications. Repeat incisions to the VNS pocket may be associated with higher incident rate of infection, highlighting a need for longer-lasting VNS pulse generator models.

Outpatient vagus nerve stimulation surgery in patients with drug-resistant epilepsy with severe intellectual disability

PURPOSE

Vagus nerve stimulation (VNS) implantation is increasingly proposed in outpatient procedure. Some epilepsy syndromes are associated with severe neurodevelopmental disabilities (intellectual disability, autism) and often motor or sensory handicaps, making ambulatory surgery more complex.

METHODS

We prospectively assessed the feasibility and safety of outpatient VNS implantation in 26 adult patients with drug-resistant epilepsy with severe intellectual disability between December 2017 and October 2020.

RESULTS

The male-to-female ratio was 0.9 and the mean age on surgery day was 23.1 years. Seventeen patients (65.4%) suffered from epileptic encephalopathy, 7 (26.9%) from cryptogenic or genetic generalized epilepsy, and 2 (7.7%) from severe multifocal epilepsy. Postoperatively, all patients were discharged the day of surgery. No patient was admitted to a hospital or have consulted within one month due to postoperative complications. There was no surgery-related complication during patients' follow-up.

CONCLUSION

Our study highlights the safety and feasibility of VNS surgery in an outpatient setting for patients with severe intellectual disability. We report detailed protocol and preoperative checklist to optimize outpatient VNS surgery in these not able-bodied patients. Severe disabilities or epilepsy-associated handicaps should not be an exclusion criterion when considering ambulatory VNS implantation.