22
AASM Membership Sections Newsletter
■
Issue #6
American Academy
of Sleep Medicine
Her clinical practice is in Sleep
Medicine and she is the Director
of the Insomnia Program at the
Northwestern Sleep Disorders Center.
Michael Howell, MD
Dr. Michael Howell, MD, is an
Associate Professor of Neurology
at the University of Minnesota.
He is the Program Director of the
Fellowship in Sleep Medicine at the
Minnesota Regional Sleep Disorders
Center, Hennepin County Medical
Center (MRSDC). He is also the
Medical Director of the Fairview
Sleep Center-Edina. He completed
his residency in neurology at the
University of Minnesota and his sleep
medicine training at the MRSDC.
His discovery work includes the
characterization and management
of parasomnias; in particular, REM
sleep behavior disorder.
Thomas W. Uhde, MD
Dr. Thomas W. Uhde, MD, is
Professor and Chair of the
Department of Psychiatry and
Behavioral Sciences at the Medical
University of South Carolina (MUSC).
He is also the Executive Director
of the Institute of Psychiatry at
the Medical University of South
Carolina and holds appointments
as clinical professor at both Wayne
State University and the Uniformed
Services University of the Health
Sciences (USUHS). His research
interests are focused on anxiety
and sleep disorders, particularly
sleep panic attacks, recurrent
isolated sleep paralysis, narcolepsy,
hypersomnia, PTSD-related
nightmares and REM behavior
disorder. ■
cutoff score for RBD). The current findings
demonstrate the high prevalence of motor
phenomena in a healthy adult sample and
stress the importance of normative data in
both research and in the clinic.
Publication 3:
Publication:
Iranzo A, Fernández-Arcos
A, Tolosa E, Serradell M, Molinuevo JL,
Valldeoriola F, Gelpi E, Vilaseca I, Sánchez-
Valle R, Lladó A, Gaig C, Santamaría
J. Neurodegenerative disorder risk in
idiopathic REM sleep behavior disorder:
study in 174 patients. PLoS One. 2014 Feb
26;9(2):e89741.
Review:
Dr. Iranzo and colleagues
describe the longitudinal risk
of phenoconversion to an overt
synucleinopathy neurodegenerative
syndrome in 174 patients (78.2% men) who
initially presented with idiopathic REM
sleep behavior disorder between 1991-
2013. Using Kaplan-Meier survival analysis,
they determined that phenoconversion
to Parkinson’s disease, mild cognitive
impairment or multiple system atrophy
occurred in 33.1% of their sample at 5 years,
75.7% at 10 years and 90.9% at 14 years
follow-up. The median interval between
idiopathic RBD diagnosis and eventual
neurodegenerative phenoconversion was
7.5 +/- 0.5 years (95% CI 6.5-8.4 years).
In all 6 autopsied patients, diffuse Lewy
body pathology was found. Along with
the cohorts from Minneapolis (Schenck
et al, Sleep Medicine 2013; 14(8):744-8)
and Montreal (Postuma et al, Neurology
2009; 72(15):1296-300), this latest (and to
date, largest) longitudinal cohort follow-
up series from Barcelona cements the
unfortunate conclusion that idiopathic
RBD is in most cases a covert form of
synucleinopathy neurodegneration (at
least when presenting as prototypical
violent parasomnia behavior in an older
adult). These data crucially inform
patient counseling, need for longitudinal
annual neurologic follow-up and eventual
neuroprotective trials (Schenck et al,
Sleep Medicine 2013; 14(8):795-806.) in
idiopathic RBD. It remains unclear whether
idiopathic or antidepressant-associated
RBD younger adult patients (i.e., under
age 50) also are destined to follow a similar
course toward overt phenoconversion to a
neurodegenerative disorder. Population-
based and non-sleep center based cohorts of
younger RBD patients also require study.
Publication 4:
Publication:
Holtbernd F, Gagnon JF,
Postuma RB, Ma Y, Tang CC, Feigin A,
Dhawan V, Vendette M, Soucy JP, Eidelberg
D, Montplaisir J. Abnormal metabolic
network activity in REM sleep behavior
disorder. Neurology. 2014 Feb 18;82(7):620-
7.
Review:
Eighty to ninety percent
of surviving patients with idiopathic
REM Sleep Behavior Disorder (RBD)
eventually develop a neurodegenerative
disorder characterized by alpha-synuclein
deposition, most commonly Parkinson’s
disease (PD), dementia with Lewy bodies
(DLB) and multiple system atrophy. PD
is associated with specific disease-related
metabolic network named the PD-related
covariance pattern (PDRP), whose
metabolic activity correlates well with
clinical manifestations of PD. This study
examined if similar cerebral networks exist
in individuals with idiopathic RBD using
brain imaging with 18F-fluorodeoxyglucose
PET and ethylcysteinate dimer SPECT. The
subgroup imaged by SPECT was followed
clinically for 4.6 years, and PDRP was
measured in all study participants. PDRP
was elevated in participants with RBD.
Further, the PDRP expression predicted
the phenoconversion from RBD to PD or
DLB. This study provides an additional
algorithm for predicting clinical evolution
of individuals affected by RBD.
