Neurogenic Orthostatic Hypotension is Common in Isolated REM Sleep Behavior Disorder
Mitchell Miglis1, Miranda M. Lim2, Jenny Zitser3, Emmanuel During4, Don Bliwise5, Dan Huddleston5, Michael Howell6, Erik St. Louis7, Jean Francois Gagnon8, Aleksandar Videnovic9, Alon Avidan10, Carlos Schenck11, Ronald Postuma12, Bradley Boeve7, Yo-El Ju13, Jonathan E. Elliott2
1Stanford University Medical Center, 2VA Portland Health Care System and Oregon Health & Science University, 3Tel Aviv Sourasky Medical Center, 4Mt Sinai, 5Emory University, 6University of Minnesota, 7Mayo Clinic, 8University of Quebec, 9MGH Neurological Clinical Research Institute, 10David Geffen School of Medicine at UCLA, 11Minnesota Regional Sleep Disorders Center, 12Montreal General Hospital, 13Washington University
Objective:
To characterize the prevalence of neurogenic orthostatic hypotension (nOH) in REM sleep behavior disorder (RBD) and associations with other prodromal features of the disease.
Background:
Rapid eye movement (REM) sleep behavior disorder (RBD) is a prodromal synucleinopathy for most patients, and the majority of individuals with isolated RBD (iRBD) will phenoconvert to clinically manifest synucleinopathy within a decade. Autonomic dysfunction is common in iRBD, however the prevalence of neurogenic orthostatic hypotension (nOH) in iRBD is unknown. We aimed to prospectively evaluate the prevalence of nOH in a large multicenter cohort of participants with iRBD.
Design/Methods:
Participants >18 years of age with overnight polysomnogram-confirmed iRBD were enrolled from the North American Prodromal Synucleinopathy (NAPS) Consortium. Participants were excluded if they were on antihypertensives or other medications that might contribute to OH. All participants underwent 3-min orthostatic stand testing with blood pressure (BP) and heart rate (HR) measurements. The ΔHR/Δ systolic BP ratio was calculated for all participants. nOH was defined as OH with a ΔHR/ΔSBP ratio of <0.5. All participants also completed a battery of questionnaires including the Scales for Outcomes in Parkinson’s Disease – Autonomic Dysfunction (SCOPA-AUT), as well as detailed cognitive, motor, and sensory testing.
Results:
334 iRBD participants met eligibility criteria. OH was identified in 87 (26%) participants, of which 69 (21%) met criteria for nOH (ΔHR/ΔSBP 0.31±0.24) and 18 (5%) met criteria non-neurogenic OH (ΔHR/ΔSBP 0.70±0.27). There was no difference in participant age, age of RBD onset, or years of education across groups. Pupillary and sexual dysfunction as measured by SCOPA-AUT subdomain scores, as well as olfaction, were all significantly worse in those with nOH and non-neurogenic OH compared to those without OH.
Conclusions:
nOH is common in those with RBD. These data support the rationale to routinely include orthostatic stand testing in the evaluation of patients with iRBD.