New Treatment Successful for Rare and Disabling Movement Disorder, the Mal de Debarquement Syndrome (MdDS)
People who suffer from a rare illness, the Mal de Debarquement Syndrome (MdDS), now have a chance for full recovery thanks to treatment developed by researchers at the Icahn School of Medicine at Mount Sinai. Their findings were published online in the July issue of Frontiers in Neurology.
People often feel a sensation of movement, called Mal de Debarquement, after they have finished boating, surfing or a sea voyage. The symptoms usually disappear within hours, but in some people, and more frequently in women, symptoms can continue for months or years, causing fatigue, insomnia, headaches, poor coordination, anxiety, depression and an inability to work. Known as the Mal de Debarquement Syndrome (MdDS), the rare condition is marked by continuous feelings of swaying, rocking or bobbing.
“Our study has provided the first effective treatment for this troublesome disorder, and we hope it provides relief to the thousands of people who may be affected worldwide,” said Bernard Cohen, MD, the Morris Bender Professor of Neurology at the Icahn School of Medicine at Mount Sinai.
Until now, there has been no effective treatment for MdDS. Diagnostic tests and early research done at Mount Sinai suggested that MdDS was caused by malfunctioning of the vestibule-ocular reflex (VOR), a mechanism in the inner ear that maintains balance and stabilizes the eyes during head movements, said Dr. Cohen.
The new treatment re-adapts the VOR by moving the visual surroundings as the head is slowly rolled from side to side at the same frequency as the subject’s symptomatic rocking, swaying or bobbing. In the study, the head roll caused vertical eye movements (nystagmus), and subjects tended to turn to one side when marching in place.
Subjects were rocked or swayed at about one cycle per five seconds. Generally, three to five treatments a day for one week were sufficient to produce a cure, and the movements and associated symptoms disappeared. Side effects of the treatments were negligible. Seventy percent of the 24 subjects that were treated in this study (21 women, three men, mean age 43.3 years) reported either a complete or substantial recovery for a mean follow-up of approximately one year after treatment. Six only had transient improvement, while one did not respond to treatment.
“The work of our team also opens up a new area of research on how the Vestibulo-Ocular Reflex can produce head and body oscillations, and may eventually provide insight into other brain diseases that cause repetitive shaking and tremor of the head and body,” Dr. Cohen said.
Mal de Debarquement Syndrome (MdDS) occurs only in a small fraction of those who experience Mal de Debarquement, and has been classified as a rare, disabling disease by the National Institutes of Health (NIH). Exact estimates of its prevalence are not available, but it was present in 1.3 percent of patients at a ‘Neuro Otology Clinic’ at the University of California, Los Angeles (UCLA). This suggests that there are hundreds of people with this syndrome in the United States and thousands worldwide, Dr. Cohen said.
Mingjia Dai, PhD, Assistant Professor of Neurology, worked closely with Dr. Cohen to develop the treatment, treated the subjects and led the group at the Icahn School of Medicine at Mount Sinai. Co-collaborators included Catherine Cho, MD, MSCR, Assistant Professor of Neurology in the Eye Movement and Vertigo Program, and Eric Smouha, MD, Associate Professor of Otolaryngology and Director of Otology-Neurotology.
The study was supported by a grant from the National Institute on Deafness and Other Communication Disorders (NIDCD), (Grant #R21, DC012162), to Dr. Dai.
About the Mount Sinai Health System
The Mount Sinai Health System is New York City's largest integrated delivery system encompassing seven hospital campuses, a leading medical school, and a vast network of ambulatory practices throughout the greater New York region. Mount Sinai's vision is to produce the safest care, the highest quality, the highest satisfaction, the best access and the best value of any health system in the nation. The System includes approximately 6,600 primary and specialty care physicians; 10 joint-venture ambulatory surgery centers; more than 140 ambulatory practices throughout the five boroughs of New York City, Westchester, Long Island, and Florida; and 31 affiliated community health centers. The Icahn School of Medicine is one of three medical schools that have earned distinction by multiple indicators: ranked in the top 20 by U.S. News & World Report's "Best Medical Schools", aligned with a U.S. News & World Report's "Honor Roll" Hospital, No. 13 in the nation for National Institutes of Health funding, and among the top 10 most innovative research institutions as ranked by the journal Nature in its Nature Innovation Index. This reflects a special level of excellence in education, clinical practice, and research. The Mount Sinai Hospital is ranked No. 18 on U.S. News & World Report's "Honor Roll" of top U.S. hospitals; it is one of the nation's top 20 hospitals in Cardiology/Heart Surgery, Gastroenterology/GI Surgery, Geriatrics, Nephrology, and Neurology/Neurosurgery, and in the top 50 in six other specialties in the 2018-2019 "Best Hospitals" issue. Mount Sinai's Kravis Children's Hospital also is ranked nationally in five out of ten pediatric specialties by U.S. News & World Report. The New York Eye and Ear Infirmary of Mount Sinai is ranked 11th nationally for Ophthalmology and 44th for Ear, Nose, and Throat, while Mount Sinai Beth Israel, Mount Sinai St. Luke's and Mount Sinai West are ranked regionally.