Accelerated TMS for Seizure-Type Functional Neurologic Disorders

Overview

The purpose of this project is to assess the feasibility, tolerability, and preliminary efficacy of using an accelerated, intermittent theta burst stimulation (a-iTBS-rTMS) protocol targeting the left dorsolateral prefrontal cortex (l-dlPFC) for Psychogenic Non-Epileptic Seizures (PNES) or Seizure-Type Functional Neurologic Disorder (FND-seiz) in an open-label fashion. Following screening, consent, and enrollment, participants will receive 6-to-10 iTBS-rTMS sessions per day (i.e., theta burst; 600 pulses per session; 6000 pulses per day) over a 3-to-5 treatment days with a target of 30 total sessions (18,000 total pulses). TMS will be targeted to Beam F3 for comparison to the bulk of the literature and to most mimic replicable and clinical use. This proposed iTBS-rTMS protocol was chosen given its previously shown safety, tolerability, and effectiveness in other conditions, but also as it has the potential to shorten treatment to only 3 days, which investigators theorize will be more feasible for patients with FND-seiz. Feasibility will be measured as the percentage of participants who receive at least 20 treatment sessions within the 3-to-5-day window. Other than self-assessments used in the safety screening process or to monitor TMS benefits and risks, secondary subjective measures will assess previously investigated FND-seiz-specific outcomes, which will be obtained prior to intervention and 4-weeks post-intervention. In addition to monthly seizure frequency, this will include validated measures regarding stigma, health-related QOL, depression, PTSD, somatic symptoms, psychosocial functioning, psychological distress, and clinical and participant impression of improvement and satisfaction. Sub-analysis will further divide participants with mild to no depression and/or PTSD versus moderate to severe depression and/or PTSD to further assess how the TMS effects known to effect other highly comorbid disorders with FND-seiz, may indirectly affect FND-seiz outcomes.

Seizure-Type Functional Neurologic Disorders (FND-seiz) are strikingly prevalent-accounting for 5-15% of epilepsy center referrals and up to 40% of epilepsy monitoring unit admissions-when considering the associated barriers to treatment and dismal outcomes. Due to resource-intensive requirements, diagnosis is often delayed by years. In the interim, patients frequently receive inappropriate antiseizure medications and have high utilization of emergency services. Years after diagnosis, many FND-seiz patients continue to experience non-epileptic seizures (NS) and have high rates of disability. Due to stigma and psychosocial barriers, engagement and responses to the standard of care, Cognitive Behavioral Therapy (CBT), are inconsistent. As many patients are told they may have epilepsy prior to receiving an accurate diagnosis, there is an obvious disconnect between the recommended psychological treatment and the physical nature of their symptoms, which can limit acceptance of the diagnosis and subsequently CBT engagement. Furthermore, the only powered RCT (the CODES trial) examining CBT in FND-seiz failed to show a significant seizure reduction at 12 months follow up and the overall effect size was lower than previously thought highlighting the limitations of a "one-size-fits-all" model for a highly comorbid disorder. Ultimately, patients with FND-seiz have been found to have a poorer overall quality of life compared to epilepsy and a standardized mortality rate 2.5 times greater the general population and comparable to that of drug-resistant epilepsy Together these factors underscore the need for alternate treatments capable of addressing psychosocial challenges unique to FND-seiz or further investigating the underlying neurobiology. Investigators theorize that offering a brain-network based approach may reduce stigma associated with confusion over the "psychological" rather than "neurological" etiologic conception of FND-seiz, which if effective, may be a more feasible for some patients. Brain-imaging research and prior reports of benefit with neurostimulation suggests TMS to the left dorsolateral prefrontal cortex (l-dlPFC) has the potential to improve cortico-limbic or cortico-sensorimotor governance, which Investigators theorize in FND-seiz may decrease NS frequency or improve quality of life. Thus, Investigators aim to investigate the feasibility and tolerability of an accelerated, intermittent theta-burst TMS protocol in FND-seiz to best mimic current clinical trends and optimize TMS feasibility, which may have several applications for the FND-seiz population. In clinical practice, the known, but rare risk of inducing an epileptic seizure with TMS and the difficulty differentiating epileptic from non-epileptic seizures, may decrease the comfort of TMS providers to use TMS in FND-seiz patients when indicated for other disabling disorders. In tandem with exploring the feasibility and tolerability of this intervention, Investigators hope to employ and investigate an informed safety protocol, with input from experts in the fields of epilepsy and brain stimulation. Helping providers safely screen patients, more decisively exclude patients with an inaccurate diagnosis or concomitant epilepsy and having a protocol to follow when treating FND-seiz patients who experience a NS during TMS stimulation may increase TMS access for FND-seiz patients with other TMS indications. Finally, as preliminary evidence here at MUSC also suggests combining TMS with CBT for other indications may have a synergistic effect and improve attrition with CBT, if TMS is preliminarily efficacious alone in FND-seiz specific outcomes in a small, open-label sample, this investigation may also help optimize future methodologies examining the use of TMS in FND-seiz.