Isolated dream‐enactment behaviours as a prodromal hallmark of rapid eye movement sleep behaviour disorder
Bei Huang, Ji-Hui Zhang, Jing Wang, S. W. Chau, J. Chan, M. W. Yu, S. Li, Li Zhou, V. Mok, Yun K. Wing, Ya-Ping Liu
Journal of Sleep Research November 21, 2022 DOI: 10.1111/jsr.13791 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Cross-sectional study Peer reviewed |
|---|---|
| Sample size | 127 |
| Population | First-degree relatives aged over 40 years of patients with REM sleep behaviour disorder |
| Key findings | Relatives of RBD patients with isolated recurrent dream-enactment behaviours showed higher rates of nightmares (27.6% vs 11.2%), current smoking (27.6% vs 3.1%), type 2 diabetes (24.1% vs 10.2%), anxiety disorder (24.1% vs 11.2%), and constipation (31.0% vs 7.1%) than matched relatives without such behaviours. The authors argue this supports isolated DEB as a possible prodromal feature of RBD and α-synucleinopathy neurodegeneration. |
Abstract
Recurrent dream‐enactment behaviours (DEB) and rapid eye movement (REM) sleep without atonia (RSWA) are two diagnostic hallmarks of REM sleep behaviour disorder (RBD), a specific prodrome of α‐synucleinopathy. Whilst isolated RSWA (without DEB) was suggested as a prodrome of RBD, the implication of ‘isolated’ recurrent DEB remains under‐investigated. In this cross‐sectional study, we sought to investigate neurodegenerative markers amongst the first‐degree relatives (FDRs, aged >40 years) of patients with RBD who underwent clinical assessment for DEB, neurodegenerative markers, and video‐polysomnography assessment. Isolated recurrent DEB was defined as: (i) three or more episodes of DEB, (ii) had a DEB episode in the past 1 year, and (iii) subthreshold RSWA. We identified 29 FDRs (mean [SD] age 53.4 [8.3] years, 55.2% male) with isolated recurrent DEB and 98 age and sex‐matched FDRs as controls. Isolated DEB was associated with nightmare (27.6% versus 11.2%, p = 0.02), and the DEB group had a higher rate of current smoking (27.6% versus 3.1%, p = 0.006), type 2 diabetes mellitus (24.1% versus 10.2%, p = 0.003), anxiety disorder (24.1% versus 11.2%, p = 0.02), and constipation (hard lump of stool, 31.0% versus 7.1%, p < 0.001) than the control group. The present findings revealed that family relatives of patients with RBD with isolated recurrent DEB have increased risk of RBD and neurodegenerative features, which adds to the emerging data that isolated DEB is a prodromal feature of RBD and α‐synucleinopathy neurodegeneration.