Polysomnographic Sleep in Idiopathic Nightmares: A Systematic Review and Meta-Analysis
Jiaxue Huang, Meiou Wang, Wenxin Bao, Wenqi Lü, Yongming Wang, Shuyao Wu, Xiangdong Tang, Rong Ren, Ye Zhang
Nature and Science of Sleep September 1, 2026 DOI: 10.2147/nss.s602539 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Systematic review and meta-analysis Peer reviewed |
|---|---|
| Sample size | 224 |
| Population | Individuals with nightmares and healthy controls |
| Topics | Dreaming |
| Key findings | Meta-analysis of seven case-control studies (112 individuals with nightmares and 112 controls) found no significant differences in sleep macro-architecture, including total sleep time, wake after sleep onset, and sleep stage percentages. The authors conclude that micro-architecture measures such as cyclic alternating pattern and power spectral analysis warrant investigation, but caution that limited data prevent confident conclusions. |
Abstract
Objectives: This study conducted a systematic evaluation of polysomnographic differences between individuals with nightmares and healthy controls.
Methods: Electronic searches of All EBM databases, EMBASE, Web of Science, and MEDLINE identified 14 eligible case-control studies; seven studies involving 112 individuals with nightmares and 112 controls were included in meta-analysis.
Results: The meta-analysis of sleep macro-architecture (such as total sleep time, wake after sleep onset, and sleep stage percentages) revealed no significant differences between individuals with nightmares and healthy controls. Furthermore, the limited available data regarding sleep micro-architecture (cyclic alternating patterns (CAP) and power spectral analysis (PSA)) and autonomic measures (heart rate and heart rate variability) in studies not subjected to meta-analysis makes it difficult to draw confident conclusions.
Conclusions: Our meta-analysis revealed no significant differences in sleep macro-architecture. This finding highlights the importance of investigating sleep micro-architecture (such as CAP and PSA), which may be relevant to the physiology of nightmares. However, these findings should be interpreted cautiously and validated in future studies because of the limited available data.
Comparable studies
Other systematic reviews and meta-analyses on dreaming, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Dreaming as mind wandering: evidence from functional neuroimaging and first-person content reports. | 2013 | Systematic review with meta-analytic comparison | |
| Lucid dreaming incidence: A quality effects meta-analysis of 50 years of research | 2016 | Meta-analysis | |
| The effectiveness of lucid dreaming therapy in patients with nightmares: A systematic review. Adults with chronic and recurring nightmares | 2023 | Systematic review | |
| The relationships between insomnia, nightmares, and dreams: A systematic review Individuals without a concomitant psychopathology, including those with insomnia or... | 2024 | Systematic review | |
| Psychosocial treatments for nightmares in adults and children: a systematic review | 2023 | Systematic review |