Stroemel-Scheder Cindy, Karmann Anna Julia, Ziegler Elisabeth, Heesen Michael, Knippenberg-Bigge Katrin, Lang Philip M, Lautenbacher Stefan
Physiological Psychology, University of Bamberg, Bamberg, Germany.
Department of Anesthesiology and Pain Therapy, Kantonsspital Baden, Baden, Switzerland.
J Pain Res. 2019 Dec 19;12:3381-3393. doi: 10.2147/JPR.S211574. eCollection 2019.
Everyday variations in night sleep in healthy pain-free subjects are at most weakly associated with pain, whereas strong alterations (eg, sleep deprivation, insomnia) lead to hyperalgesic pain changes. Since it remains unclear how substantial sleep alterations need to be in order to affect the pain system and lead to a coupling of both functions, the present study aimed at providing sufficient variance for co-variance analyses by examining a sample consisting of both healthy subjects and chronic pain patients.
A sample of 20 chronic musculoskeletal pain patients and 20 healthy controls was examined. This sample was assumed to show high inter-individual variability in sleep and pain, as pain patients frequently report sleep disturbances, whereas healthy subjects were required to be pain-free and normal sleepers. Sleep of two non-consecutive nights was measured using portable polysomnography and questionnaires. Experimental pain parameters (pressure pain thresholds (PPT), temporal summation of pain (TSP), conditioned pain modulation (CPM)) and situational pain catastrophizing (SCQ) were assessed in laboratory sessions before and after sleep. Pain patients' clinical pain was assessed via questionnaire.
As expected, both groups differed in several sleep parameters (reduced total sleep time and sleep efficiency, more time awake after sleep onset, lower subjective sleep quality in the patients) and in a few pain parameters (lower PPTs in the patients). In contrast, no differences were found in TSP, CPM, and SCQ. Contrary to our expectations, regression analyses indicated no prediction of overnight pain changes by sleep parameters.
Since sleep parameters were hardly apt to predict overnight pain changes, this leaves the association of both systems mainly unproven when using between-subject variance for verification.
在无疼痛的健康受试者中，夜间睡眠的日常变化与疼痛至多仅有微弱关联，而强烈的改变（如睡眠剥夺、失眠）会导致痛觉过敏的疼痛变化。由于目前尚不清楚睡眠改变需要达到何种程度才能影响疼痛系统并导致两种功能的耦合，本研究旨在通过对健康受试者和慢性疼痛患者组成的样本进行检查，为协方差分析提供足够的变异性。
对20名慢性肌肉骨骼疼痛患者和20名健康对照者进行了样本检查。假设该样本在睡眠和疼痛方面表现出较高的个体间变异性，因为疼痛患者经常报告睡眠障碍，而健康受试者要求无疼痛且睡眠正常。使用便携式多导睡眠图和问卷测量两个非连续夜晚的睡眠情况。在睡眠前后的实验室环节中评估实验性疼痛参数（压力疼痛阈值（PPT）、疼痛时间总和（TSP）、条件性疼痛调制（CPM））和情境性疼痛灾难化（SCQ）。通过问卷评估疼痛患者的临床疼痛情况。
正如预期的那样，两组在几个睡眠参数（总睡眠时间和睡眠效率降低、睡眠开始后清醒时间增加、患者主观睡眠质量较低）和一些疼痛参数（患者的PPT较低）方面存在差异。相比之下，在TSP、CPM和SCQ方面未发现差异。与我们的预期相反，回归分析表明睡眠参数无法预测夜间疼痛变化。
由于睡眠参数几乎无法预测夜间疼痛变化，因此在使用受试者间变异性进行验证时，这两个系统之间的关联主要仍未得到证实。
