Essential Tremor: Current Concepts and Controversies

Dr. Kuo is a Movement Disorders specialist caring for patients with cerebellar ataxia, including spinocerebellar ataxia and multiple system atrophy, and a variety of other movement disorders, such as essential tremor and Parkinson’s disease. As a physician-scientist, his research is funded by National Institutes of Health to study the role of the cerebellum in movement disorders, implicating in ataxia and tremor. He leads a multi-disciplinary research team(link is external and opens in a new window) to study the disease mechanism and to develop therapies for movement disorders via translational research and clinical trials. Dr. Kuo is the Director for the Initiative for Columbia Ataxia and Tremor(link is external and opens in a new window) (ICAT), an interdisciplinary research group to study how the cerebellum plays a role in neurological and neurodegenerative disorders. He also serves as one of the tri-leaders for the Clinical Research Consortium for Spinocerebellar Ataxias, constituting 15 medical centers in the U.S. to study patients living with spinocerebellar ataxias. Aiming to promote research collaboration, Dr. Kuo organizes International Tremor Congress(link is external and opens in a new window) every other year, bringing researchers together to advance therapies for tremor. He was elected in 2020 as the Vice Chair for the Movement Disorders Section at American Academy of Neurology(link is external and opens in a new window). Dr. Kuo has received multiple scientific awards as the recognition of his contributions to neurology, including 2016 Louis V. Gerstner Jr. Scholar Merit Award, 2019 American Academy of Neurology Jon Stolk Award for Movement Disorders, and 2020 American Neurological Association Derek Denny-Brown Award. Elan Louis, M.D., is Professor and Chair of the Department of Neurology at UT Southwestern Medical Center. He specializes in disorders of involuntary movement and is considered the world’s leading scholar in essential tremor (ET). Dr. Louis earned his medical degree at Yale University and a master’s degree in epidemiology at Columbia University. He completed a residency in neurology at Columbia-Presbyterian Medical Center and then received advanced training in movement disorders and neuroepidemiology through fellowships at Columbia University. Dr. Louis served in Yale University’s Department of Neurology from 2015 to 2020 as a tenured Professor of Neurology and Epidemiology, Chief of the Movement Disorders Division, Associate Chair of Outpatient Clinical Research, and Co-Director of the Center for Neuroepidemiology and Clinical Neurological Research. Prior to that, he was a tenured Professor of Neurology and Epidemiology at Columbia University’s College of Physicians and Surgeons, where he was also the Associate Chairman for Academic Affairs and Faculty Development. Certified by the American Board of Psychiatry and Neurology, Dr. Louis joined the UT Southwestern faculty in 2020. Dr. Louis’s research focuses on the genetics, epidemiology, and pathophysiology of tremor disorders. His work on essential tremors has been cited in the New York Times as “pioneering,” and, in fact, his research has challenged many of the prevailing notions about ET and has substantially recreated the dialogue in the ET field. He collaborates with investigators in Spain, Turkey, Mexico, and other countries, examining the epidemiology of ET in these populations. Dr. Louis established the Essential Tremor Centralized Brain Repository – a national centralized brain bank for the study of ET. He has received continuous funding from the National Institutes of Health (NIH) since 1995 and continuous R01 funding since 2000, as well as funding from the International Essential Tremor Foundation, the Charles A. Dana Foundation, the Parkinson's Disease Foundation, and a Paul Beeson Physician Faculty Scholars Award from the American Federation for Aging Research. He has authored more than 700 peer-reviewed scientific articles and book chapters and written invited editorials and reviews for Annals of Neurology, New England Journal of Medicine, and Lancet Neurology. He is the founding Editor-in-Chief of Tremor and Other Hyperkinetic Movements, and he serves on the editorial board of more than 10 other scholarly journals He is also the editor of Merritt’s Textbook of Neurology, one of the premier general neurology textbooks in the country. Dr. Louis has served on multiple medical advisory boards, including the boards of the International Essential Tremor Foundation, the Tremor Action Network, and HopeNET, and he is a member of the American Academy of Neurology, the American Neurological Association, and the International Parkinson and Movement Disorder Society. He is committed to the care of patients with involuntary movements and has been listed by Castle Connolly as one of the Top Doctors in the field of Neurology.

1. What’s in a name? nomenclature of essential tremor- syndrome or family of diseases? Louis & Kuo Is essential tremor a family of diseases or a syndrome? A family of diseases Riboldi & Frucht Is essential tremor a family of diseases or a syndrome? A syndrome Pandey

2. Essential tremor- Is this an electrical or a degenerative disorder? Or is it both? Louis & Kuo Is essential tremor a degenerative disorder or an electric disorder? A degenerative disorder Faust Is essential tremor a degenerative disorder or an electric disorder? An electric disorder Cho

3. How important is the inferior olive in essential tremor? An evolving story Kuo & Louis Is inferior olive central to the pathophysiology of essential tremor? Yes Lang & Handforth Is inferior olive central to the pathophysiology of essential tremor? No Manto

4. Essential tremor as a harbinger- what is the cognitive fallout of having essential tremor? Louis & Kuo Does essential tremor increase the risk of dementia? Yes Cosentino & Shih Does essential tremor increase the risk of dementia? No Rajput

5. Is essential tremor a disorder primarily due to GABA dysfunction? Kuo & Louis Is essential tremor a disorder of primary GABA dysfunction? Yes Gironell Is essential tremor a disorder of primary GABA dysfunction? No Bellows &Jimenez-Shahed

6. The future of pharmacotherapies for essential tremor: enhancing GABA neurotransmission or reducing neuronal hyper-excitability? Kuo & Louis What is the next generation of medication for essential tremor? Enhancing GABAergic inhibition Ondo What is the next generation of medication for essential tremor? Reduction of hyper-excitability Shukla