创伤后应激障碍（Post-traumatic stress disorder，PTSD）是个体经历一个或多个创伤事件后出现的一种以闯入性创伤情感记忆、高警觉性和回避为主要临床表现的精神障碍。既往研究表明，创伤幸存者的夜间睡眠障碍对创伤相关恐惧情感记忆的异常巩固与强化以及PTSD的发生发展起重要作用。已有学者提出，PTSD患者夜间睡眠障碍应作为该疾病的临床核心表现。2018年，美国圣安东尼奥军事医疗中心Vincent Mysliwiec教授首次提出“创伤相关睡眠障碍（Trauma associated sleep disorder，TASD）”应作为一种独立的睡眠疾病存在。
本研究通过对既往已发表的PTSD客观睡眠研究数据进行meta分析，系统探讨了PTSD患者夜间睡眠结构特征变化。同时，综合考虑了PTSD的临床异质性特点，探讨了患者一般人口学因素、创伤事件类型（战争、自然灾害、性暴力等）、抗抑郁药及镇静催眠药使用等因素对PTSD患者夜间睡眠结构的影响。结果发现与健康对照组相比，PTSD患者夜间总睡眠时间减少、睡眠效率降低、入睡后觉醒时间增加、慢波睡眠比例减少。进一步分析发现，女性PTSD患者较男性患者更易出现夜间客观睡眠数量减少及睡眠质量下降；抗抑郁药的使用可能导致患者夜间睡眠障碍更加明显；患者所经历的创伤事件类型不同，睡眠结构特征不同。不仅如此，PTSD症状量表评分越高，患者慢波睡眠比例减少越明显，提示慢波睡眠比例减少可能是反映PTSD临床症状严重程度的重要电生理标志。
PTSD动物模型研究表明，创伤后快速眼球运动期（REM）睡眠紊乱可能是创伤相关恐惧情感记忆形成的病理生理学基础。本研究通过对大样本PTSD患者分析发现，年龄小于30岁的PTSD患者更容易出现REM睡眠比例下降，而年龄大于30岁的患者REM睡眠比例与健康对照组相比无明显差异，间接提示REM睡眠比例在创伤事件发生后出现先下降后逐渐恢复正常水平的变化特点。该研究结果还提示未来探索针对创伤后早期REM睡眠紊乱的有效干预手段可能有助于预防PTSD的发生发展。美国霍华德大学医学院精神病学与行为科学系Thomas A. Mellman教授于Sleep Medicine Reviews同期发表特邀评论文章高度评价本研究的理论及实践意义。
本研究在中国国家自然科学基金委重点（81530002）和国际合作（81629002）及科技部973（2015CB856406）等研究基金资助下完成。
Thomas A. Mellman教授：By providing a comprehensive, up-to-date, methodologically sound review and meta-analysis of sleep studies of posttraumatic stress disorder (PTSD) with analysis of multiple relevant covariates, Zhang et al. have made a valuable contribution to the literature on a critically important aspect of PTSD. The findings of Zhang et al. increase confidence that, overall, there is objective evidence of disrupted sleep with PTSD and that the evidence is stronger for younger, female, and civilian trauma-exposed populations. Of further interest is that the differences were a function of comparisons with controls characterized as healthy as opposed to controls who were recruited for being trauma-exposed. A factor contributing to differences not being observed with trauma-exposed controls could be the insomnia/sleep disturbance that develops post-trauma absent a diagnosis of PTSD that is not uncommon in trauma-exposed cohorts. In addition, Zhang et al. found that rapid eye movement sleep (REMS) percentage is diminished in PTSD, compared with controls, among studies with participants less than 30 y of age. PTSD related to childhood trauma is not well represented in the sleep PTSD literature, so it is likely (as suggested by the authors) that younger age is a surrogate for more recent onset of PTSD in their analysis. Therefore, the extant literature continues to support that during acute and early phases of PTSD there are factors inhibiting and/or disrupting REMS.
The new report by Zhang et al. adds coherence to conceptualizing findings and provides a point of reference for future studies. Understanding sleep patterns with PTSD is critical for effectively target distressing symptoms that exacerbate other features of the disorder and interfere with adaptive emotional processing. In addition, sleep is a state that when achieved is relatively unencumbered by the environment and an individual's intent, and the neurobiological regulation and substrates of sleep are relatively well understood. Hopefully, with nuanced consideration of individual/clinical factors, and further application of emerging molecular, neuroimaging and other research tools, continuing investigation of sleep in PTSD will contribute to realizing personalized/precision approaches to preventing and promoting recovery from PTSD.
