Stanford ME/CFS Initiative, Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, United States of America.
PLoS One. 2018 Jun 1;13(6):e0197811. doi: 10.1371/journal.pone.0197811. eCollection 2018.
Post-exertional malaise (PEM) is considered to be the hallmark characteristic of myalgic encephalomyelitis/ chronic fatigue syndrome (ME/CFS). Yet, patients have rarely been asked in formal studies to describe their experience of PEM.
To describe symptoms associated with and the time course of PEM.
One hundred and fifty subjects, diagnosed via the 1994 Fukuda CFS criteria, completed a survey concerning 11 symptoms they could experience after exposure to two different types of triggers. We also inquired about onset and duration of PEM and included space for subjects to write in any additional symptoms. Results were summarized with descriptive statistics; McNemar's, paired t-, Fisher's exact and chi-square goodness-of-fit tests were used to assess for statistical significance.
One hundred and twenty-nine subjects (90%) experienced PEM with both physical and cognitive exertion and emotional distress. Almost all were affected by exertion but 14 (10%) reported no effect with emotion. Fatigue was the most commonly exacerbated symptom but cognitive difficulties, sleep disturbances, headaches, muscle pain, and flu-like feelings were cited by over 30% of subjects. Sixty percent of subjects experienced at least one inflammatory/ immune-related symptom. Subjects also cited gastrointestinal, orthostatic, mood-related, neurologic and other symptoms. Exertion precipitated significantly more symptoms than emotional distress (7±2.8 vs. 5±3.3 symptoms (median, standard deviation), p<0.001). Onset and duration of PEM varied for most subjects. However, 11% reported a consistent post-trigger delay of at least 24 hours before onset and 84% endure PEM for 24 hours or more.
This study provides exact symptom and time patterns for PEM that is generated in the course of patients' lives. PEM involves exacerbation of multiple, atypical symptoms, is occasionally delayed, and persists for extended periods. Highlighting these characteristics may improve diagnosis of ME/CFS. Incorporating them into the design of future research will accelerate our understanding of ME/CFS.
运动后不适（PEM）被认为是肌痛性脑脊髓炎/慢性疲劳综合征（ME/CFS）的标志性特征。然而，在正式研究中，很少有患者被要求描述他们的 PEM 体验。
描述 PEM 相关症状及其时间进程。
150 名符合 1994 年 Fukuda CFS 标准的患者完成了一项关于他们在接触两种不同类型的触发因素后可能经历的 11 种症状的调查。我们还询问了 PEM 的发作和持续时间，并为患者留出了填写任何其他症状的空间。结果用描述性统计数据进行总结；采用 McNemar 卡方检验、配对 t 检验、Fisher 确切概率检验和卡方拟合优度检验评估统计学意义。
129 名（90%）患者在体力和认知劳累以及情绪困扰后均出现 PEM。几乎所有患者都因劳累而加重，但 14 名（10%）患者表示情绪无影响。疲劳是最常见的加重症状，但认知困难、睡眠障碍、头痛、肌肉疼痛和流感样感觉也被 30%以上的患者提到。60%的患者至少出现一种炎症/免疫相关症状。患者还提到了胃肠道、直立性低血压、情绪相关、神经和其他症状。劳累引发的症状明显多于情绪困扰（7±2.8 与 5±3.3 个症状（中位数，标准差），p<0.001）。大多数患者的 PEM 发作和持续时间各不相同。然而，11%的患者报告说在发作前至少有 24 小时的一致触发延迟，84%的患者持续 24 小时或更长时间的 PEM。
本研究提供了在患者日常生活中发生的 PEM 的具体症状和时间模式。PEM 涉及多种非典型症状的加重，偶尔会延迟，并持续较长时间。强调这些特征可能有助于 ME/CFS 的诊断。将它们纳入未来研究的设计将加速我们对 ME/CFS 的理解。
