Authors :
Presenting Author: Tamara Jafar, BS – University of Southern California
Mani Ratnesh Sandhu, MD – Resident, Neurosurgery, Universtiy of Iowa Hospitals and Clinics; Benjamin Gruenbaum, MD, PhD – Mayo Clinic; Tore Eid, Md, PhD – Yale University; Robert Duckrow, MD – Yale University; Dennis Spencer, MD – Yale University; Hitten Zaveri, PhD – Yale University
Rationale: Patients with drug-resistant epilepsy are faced with the challenge of uncontrolled seizures and the added burden of psychiatric comorbidities. Depression is the most common comorbidity of epilepsy; epileptic patients display a four to five higher rate of depression and suicide compared with healthy population (Blaszczyk 2016). There is a growing interest in the role of neurostimulation techniques, including deep brain stimulation (DBS), responsive neurostimulation (RNS), and vagus nerve stimulation (VNS), for managing both epilepsy and psychiatric comorbidities. By reviewing the existing literature, we seek to provide insights into the potential benefits of neurostimulation in this patient population.
Methods: Following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, a systematic review was performed of studies, until June 2023, reporting outcomes following DBS, RNS, and VNS implantation in drug-resistant epilepsy. Specific search criteria were used for DBS (“deep brain stimulation,” “DBS,” “anterior thalamic nucleus,” in the title and “epilepsy” or “seizure”), RNS (“responsive neurostimulation” or “RNS” in the title and “epilepsy” or “seizure”), VNS (“vagus,” “vagal,” or “VNS” in the title and “epilepsy” or “seizure”), and “psychiatric disorders,” “depression,” “anxiety,” “mood disorders,” and “obsessive compulsive disorder.”
Results: With above selection criteria, 136 underwent full-text reviews, and 111 studies were included. Sufficient data for meta-analysis were available from forty-three studies for DBS (n = 417 patients), for RNS (eighteen studies, n = 541), and for VNS (ten studies, n = 510). The mean follow up duration for RNS was 20.65 months, for DBS 30.57 months, and for VNS 19.2 months. After RNS implantation, 6% of patients had depression and other comorbidities. Several studies have shown improvement in depression and anxiety scores after DBS in patients (Witt 2008, Funkiewiez 2004). The meta-analysis demonstrated that neurostimulation was associated with a significant reduction in psychiatric symptom severity in patients with drug resistant epilepsy and comorbid psychiatric conditions.
Conclusions: A meta-analysis of recent literature on neurostimulation techniques, including DBS, RNS, VNS demonstrates potential benefits in managing both drug-resistant epilepsy and psychiatric comorbidities. DBS has shown promise in reducing seizure frequency and improving psychiatric symptoms associated with drug-resistant epilepsy. RNS and VNS have demonstrated efficacy in reducing seizures and preliminary evidence suggests potential benefits in improving depressive and anxiety symptoms.
Funding: None