Exploring the Adoption of Implantable Brain Stimulation into Standard of Care for Central Nervous System Disorders: Proceedings of a Workshop (2024)

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¹ The planning committee’s role was limited to planning the workshop, and the Proceedings of a Workshop was prepared by the workshop rapporteurs as a factual summary of what occurred at the workshop. Statements, recommendations, and opinions expressed are those of individual presenters and participants and are not necessarily endorsed or verified by the National Academies of Sciences, Engineering, and Medicine, and they should not be construed as reflecting any group consensus.

² For more information on DBS, see https://www.hopkinsmedicine.org/health/treatment-tests-and-therapies/deep-brain-stimulation (accessed January 23, 2024).

³ For more information on responsive neurostimulation, see https://www.epilepsy.com/stories/what-responsive-neurostimulation (accessed January 23, 2024).

⁴ For more information on the history of DBS and regulatory approvals, see https://www.ninds.nih.gov/about-ninds/what-we-do/impact/ninds-contributions-approved-therapies/deep-brain-stimulation-dbs-treatment-parkinsons-disease-and-other-movement-disorders (accessed February 26, 2024).

dystonia, epilepsy, and obsessive-compulsive disorder (OCD) (Krauss et al., 2021; Lozano and Lipsman, 2013). Despite this growth, however, there remain unanswered questions about how implantable brain stimulation can be integrated into the standard of care across applicable CNS disorders.

To date, implantable brain stimulation has been most integrated into the standard of care for Parkinson’s disease, as it is used regularly to relieve symptoms such as tremor, on-off fluctuations, and dyskinesia. It works by stimulating the basal ganglia, which can result in an altered basal ganglion neuron firing rate and pattern, increased calcium and neurotransmitter release, and increased blood flow and neurogenesis (Lee et al., 2004; Tawfik et al., 2010; Wichmann et al., 2011). However, it is unclear how these stimulation effects specifically influence Parkinson’s disease symptoms (Okun, 2012).

Despite FDA approval via a humanitarian device exemption for the use of DBS in OCD and promising research in other psychiatric disorders, the use of implantable brain stimulation lags significantly behind other therapeutics. Barriers contributing to its application for psychiatric disorders include limitations in the current knowledge of the neural circuitry underlying these disorders, a lack of understanding of which physiologic changes from implantable brain stimulation are beneficial for which mental illnesses, and a need to identify which approaches are most appropriate for various subgroups of patients (Bilge et al., 2018; Holtzheimer and Mayberg, 2011). There is also a lack of coverage by private insurers for FDA-approved psychiatric indications that can restrict patient access to the therapy (Davis et al., 2021).

For Parkinson’s disease, essential tremor, epilepsy, and psychiatric disorders, a number of challenges preclude the widespread adoption of implantable brain stimulation. One such challenge will be finding ways to making the technology scalable and sustainable. For example, the neurosurgery required to implant a brain stimulation device, coupled with the device’s maintenance, are expensive and might not be reimbursable costs by insurers, especially for off-label therapies (Rossi et al., 2017; Vedam-Mai et al., 2021). If implantable brain stimulation is to be adopted into routine clinical care, addressing barriers such as reimbursement and accessibility may be important to ensure widespread patient adoption.

Both patient and physician engagement play an important role in advancing the use of implantable brain stimulation in clinical care. In a recent study, a survey conducted among patients with Parkinson’s disease found that while patients had reliable knowledge of the procedure and potential side effects, there were still common misconceptions such as believing that implantable brain stimulation would alter the natural course of the disease (Chitnis et al., 2023). Unfortunately, patients who have heard of and are interested in implantable brain stimulation often report feeling

that they were denied treatment from their providers, perhaps because of clinicians’ perception that these technologies are a “last resort” (Borovečki et al., 2023; Lökk, 2011). This perception and a lack of physician and patient education can have ethical implications on patient selection, expectations, and consent (Schermer, 2011).

Despite implantable brain stimulation’s increased use in clinical care, there remain unaddressed barriers to fully adopting this technology into the standard of care for CNS disorders. To better understand the current state of clinical use of the technology as well as patient and physician education and economic considerations related to the technology, on October 31, 2023, the Forum on Neuroscience and Nervous System Disorders of the National Academies of Sciences, Engineering, and Medicine held a workshop, Exploring the Adoption of Implantable Brain Stimulation into Standard of Care for Central Nervous System Disorders.⁵ Participants included clinicians and clinical researchers interested in the use of implantable brain stimulation to treat CNS disorders, several individuals who had differing experiences with implantable brain stimulation, representatives from federal regulatory and funding agencies, officers of advocacy organizations and health systems, and innovators and executives from companies that manufacture implantable devices for treating CNS disorders. Given that implantable brain stimulation is primarily used for movement disorders, a larger portion of the workshop and this proceedings focused on lessons learned from this disease space, which may be useful to other CNS disorders moving forward.

WORKSHOP OBJECTIVES

Tim Denison, a professor of engineering science and clinical neurosciences at Oxford University and co-founder and chief scientific officer of Amber Therapeutics Ltd., described the workshop objectives in his introductory comments. The overall objective was to examine the current state of implantable brain stimulation in the treatment of CNS disorders, the current barriers to adopting this technology into standard of care, and opportunities for scalable utility in the future (see Box 1-1). More specifically, the workshop examined various barriers to the widespread adoption of implantable brain stimulation and what would be required to overcome these barriers. Denison identified four areas in which barriers may exist: (1) clinical necessity and including the lived experience throughout the design process to create solutions and treatments that will improve patient’s lives

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⁵ To learn more about the workshop, see https://www.nationalacademies.org/event/40129_10-2023_exploring-the-adoption-of-implantable-brain-stimulation-into-standard-of-care-for-central-nervous-system-disorders-a-workshop (accessed November 26, 2023).

in a meaningful way, (2) regulatory pathways, (3) workflow viability that considers what clinicians need to adopt new technology, and (4) economic viability that examines what pathways and incentives are necessary to scale this technology.

ORGANIZATION OF THE PROCEEDINGS

This proceedings summarizes the presentations and discussions from the workshop (see Appendix B for the workshop agenda).

Chapter 2 reviews the current state of knowledge regarding the clinical use of implantable brain stimulation for several CNS disorders and discusses lessons learned from approved neuromodulation therapies, cochlear and retinal implants, responsive neurostimulation for epilepsy, and DBS for OCD. Particular attention was paid to the issue of “crossing the chasm,” that is, moving a technology from pilot research and early adopters to mainstream clinical practice. Chapter 3 offers a firsthand look at the experiences of people with various disorders that implantable brain stimulation can address, with the goal of keeping patients at the center of efforts to expand the adoption of this technology.

The next three chapters examine numerous practical barriers to the acceptance of implantable brain stimulation as standard of care. Chapter 4 examines issues related to patient selection and engagement that may hinder increased adoption. Chapter 5 focuses on the roles that professional education and other factors play in leading clinicians to adopt new technologies or existing technologies for different roles. Chapter 6 explores how reimbursement and other economic considerations can speed up or slow down the adoption of a novel treatments.

Finally, Chapter 7 reviews the key points individual speakers made during the workshop and highlights potential next steps for moving the field forward. The references list includes all sources mentioned in Chapters 1–7, and the workshop agenda is provided in Appendix B.

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