Gender differences in clinical findings and α-synucleiopathy-related markers in patients with idiopathic REM sleep behavior disorder

Noboru Takeuchi; Taeko Sasai-Sakuma; Yuichi Inoue

doi:10.1016/j.sleep.2019.11.1261

Gender differences in clinical findings and α-synucleiopathy-related markers in patients with idiopathic REM sleep behavior disorder

Sleep Med. 2020 Feb:66:216-219. doi: 10.1016/j.sleep.2019.11.1261. Epub 2019 Dec 17.

Authors

Noboru Takeuchi¹, Taeko Sasai-Sakuma², Yuichi Inoue³

Affiliations

¹ Yoyogi Sleep Disorder Center, Japan; Department of Neuropsychiatry, Kurume University, Japan.
² Department of Clinical Laboratory Science, Faculty of Medical Technology, Teikyo University, Japan; Department of Sleep Medicine, Tokyo Medical University, Japan. Electronic address: staeko@med.teikyo-u.ac.jp.
³ Yoyogi Sleep Disorder Center, Japan; Department of Sleep Medicine, Tokyo Medical University, Japan.

PMID: 31978865
DOI: 10.1016/j.sleep.2019.11.1261

Abstract

Background: Rapid eye movement (REM) sleep behavior disorder (RBD) is a male-predominant parasomnia. Earlier clinical RBD patient studies showed gender differences of clinical symptoms and polysomnographic (PSG) findings. However, no previous investigated this issue by means of validated severity scales or by neuropsychological examination related to alpha-synucleinopathy. This study elucidates gender differences in clinical, physiological, and neuropsychological findings in Japanese idiopathic RBD (iRBD) patients.

Methods: From 220 patients with complaint of sleep-related vocalization or behaviors who visited Yoyogi Sleep Disorder Center from June 2003 through December 2016, 43 female (68.7 ± 7.3 yr) and 141 male patients (66.7 ± 6.7 yr) diagnosed as having iRBD by video-polysomnography (v-PSG) were selected. All subjects answered the RBD questionnaire (RBDQ-JP) and underwent olfactory function test (Sniffin' Sticks test) and cognitive function test (MoCA-J).

Results: Female iRBD patients had later first symptom-witnessed age (sleep-talking 63.2 ± 10.5 yr, behaviors 60.9 ± 8.6 yr) than male patients (sleep-talking 59.1 ± 8.8 yr, behaviors 64.7 ± 8.9 yr). No gender difference was found in age at diagnosis, clinical severity (RBDQ-JP), or olfactory or cognitive function. Regarding electromyogram (EMG) findings during REM sleep, phasic EMG activity was higher in female patients (22.3 ± 17.8% vs. 16.5 ± 16.1%), although no difference was found in tonic EMG activity.

Conclusions: Although female iRBD patient symptoms were first recognized later than those of male patients, they showed elevated EMG activity during REM sleep and showed deteriorated olfactory and cognitive function similarly to male patients at the first medical consultation. Results suggest that disease progression in female RBD patients is equivalent to that in male patients.

Keywords: Cognitive function; Gender difference; Olfactory function; REM atonia loss; Rapid eye movement sleep behavior disorder.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Age of Onset
Aged
Biomarkers*
Cognition / physiology*
Electromyography
Female
Humans
Japan
Male
Neuropsychological Tests
Olfactory Perception / physiology*
Polysomnography
REM Sleep Behavior Disorder / physiopathology*
Sex Factors
Synucleinopathies*

Substances

Biomarkers