Department of Psychology, University of Salzburg, Laboratory for Sleep, Cognition, and Consciousness Research, Salzburg, Austria.
University of Salzburg, Centre for Cognitive Neuroscience, Salzburg, Austria.
Eur J Neurol. 2019 Aug;26(8):1051-1059. doi: 10.1111/ene.13935. Epub 2019 Mar 19.
Healthy circadian rhythmicity has been suggested to relate to a better state of brain-injured patients and to support the emergence of consciousness in patient groups characterized by a relative instability thereof such as patients with disorders of consciousness (DOC).
Going beyond earlier studies, a systems-level perspective was adopted and, using multilevel modelling, the joint predictive value of three indices of circadian rhythm integrity derived from skin temperature variations, melatoninsulfate secretion, and physical activity (wrist actigraphy) patterns was evaluated for the behaviourally assessed state [Coma Recovery Scale - Revised (CRS-R) score] of DOC patients [13 unresponsive wakefulness syndrome; seven minimally conscious (exit) state]. Additionally, it was assessed in a subset of 16 patients whether patients' behavioural repertoire (CRS-R score) varied (i) with time of day or (ii) offset from the body temperature maximum (BT ), i.e. when cognitive performance is expected to peak.
The results reveal that better integrity of circadian melatoninsulfate and temperature rhythms relate to a richer behavioural repertoire. Moreover, higher CRS-R scores are, by trend, related to assessments taking place at a later daytime or deviating less from the pre-specified time of occurrence of BT .
In conclusion, the results suggest that therapeutic approaches aimed at improving circadian rhythms in brain-injured patients are promising and should be implemented in hospitals or nursing homes. Beyond this, it might be helpful to schedule diagnostic procedures and therapies around the (pre-assessed) BT (≈4 pm in healthy individuals) as this is when patients should be most responsive.
健康的昼夜节律性被认为与脑损伤患者的更好状态有关，并支持意识在以相对不稳定为特征的患者群体中出现，例如意识障碍（DOC）患者。
超越早期研究，采用系统水平的观点，并使用多层次建模，评估了从皮肤温度变化、褪黑素分泌和身体活动（腕部动作）模式中得出的三个昼夜节律完整性指标对行为评估状态（昏迷恢复量表修订版（CRS-R）评分）的预测价值DOC 患者[13 例无反应性觉醒综合征；7 例最小意识（出口）状态]。此外，在 16 名患者的亚组中评估了患者的行为范围（CRS-R 评分）是否（i）随时间变化或（ii）与体温最大值（BT）偏移，即当认知表现预计达到峰值时。
结果表明，昼夜节律褪黑素和温度节律的完整性较好与更丰富的行为范围相关。此外，较高的 CRS-R 评分趋势与在较晚的白天进行的评估相关，或与 BT 发生时间的偏差较小。
总之，这些结果表明，旨在改善脑损伤患者昼夜节律的治疗方法很有前途，应在医院或疗养院实施。除此之外，围绕（预先评估的）BT（健康个体约为 4 下午）安排诊断程序和治疗可能会有所帮助，因为这是患者最敏感的时候。
