Abstract：
OBJECTIVE: Idiopathic/isolated REM sleep behavior disorder (iRBD) is widely regarded as an early sign of neurodegeneration leading to synucleinopathies. While circadian rhythm alterations in iRBD have been preliminarily demonstrated, evidence on melatonin secretion patterns in this clinical condition is limited. To address this knowledge gap, this exploratory study aimed to integrate salivary melatonin measurement with actigraphic monitoring in individuals with iRBD and age-matched healthy controls (HC) under real-life conditions.
METHODS: Participants diagnosed with iRBD and HC underwent clinical evaluation and wore an actigraph for seven days and nights. Salivary melatonin concentrations were measured at five time points during the last night of recording. Comparative analyses were conducted on clinical data, actigraphic parameters, and melatonin levels between the two groups.
RESULTS: iRBD participants (n = 18) showed greater motor (p < 0.01) and non-motor symptoms (p < 0.001), alongside disruptions in circadian sleep-wake rhythm compared to HC (n = 10). Specifically, actigraphy revealed a delayed central phase measurement (p < 0.05), reduced activity during the most active hours (p < 0.001), and decreased relative amplitude (p < 0.05). Total salivary melatonin concentration was significantly lower in iRBD (p < 0.05), with a slight but non-significant phase delay in dim light melatonin onset.
CONCLUSIONS: This exploratory study highlights a dysregulation of circadian sleep-wake rhythm coupled with reduced melatonin secretion in iRBD. Future research could add to these preliminary findings to evaluate novel treatment approaches to regulate the sleep-wake cycle and elucidate the implications of circadian dysregulation in the conversion from iRBD to neurodegeneration.
METHODS: Participants diagnosed with iRBD and HC underwent clinical evaluation and wore an actigraph for seven days and nights. Salivary melatonin concentrations were measured at five time points during the last night of recording. Comparative analyses were conducted on clinical data, actigraphic parameters, and melatonin levels between the two groups.
RESULTS: iRBD participants (n = 18) showed greater motor (p < 0.01) and non-motor symptoms (p < 0.001), alongside disruptions in circadian sleep-wake rhythm compared to HC (n = 10). Specifically, actigraphy revealed a delayed central phase measurement (p < 0.05), reduced activity during the most active hours (p < 0.001), and decreased relative amplitude (p < 0.05). Total salivary melatonin concentration was significantly lower in iRBD (p < 0.05), with a slight but non-significant phase delay in dim light melatonin onset.
CONCLUSIONS: This exploratory study highlights a dysregulation of circadian sleep-wake rhythm coupled with reduced melatonin secretion in iRBD. Future research could add to these preliminary findings to evaluate novel treatment approaches to regulate the sleep-wake cycle and elucidate the implications of circadian dysregulation in the conversion from iRBD to neurodegeneration.
摘要：
目的：特发性/孤立性REM睡眠行为障碍（iRBD）被广泛认为是导致突触核蛋白病的神经变性的早期征兆。虽然已初步证明iRBD的昼夜节律改变，关于褪黑素分泌模式在这种临床情况下的证据是有限的。为了解决这个知识差距，这项探索性研究旨在在现实生活条件下,在iRBD患者和年龄匹配健康对照(HC)患者中,将唾液褪黑素测量与肌动监测相结合.
方法：诊断为iRBD和HC的参与者接受了临床评估，并佩戴了7个昼夜的活动记录仪。在记录的最后一个晚上的五个时间点测量唾液褪黑素浓度。对临床数据进行了比较分析，活动参数，和褪黑激素水平在两组之间。
结果：iRBD参与者（n=18）表现出更大的运动（p<0.01）和非运动症状（p<0.001），与HC相比，昼夜节律睡眠-觉醒节律中断（n=10）。具体来说,肌动描记术显示延迟的中心相位测量(p<0.05)，在最活跃的时间内活动减少（p<0.001），相对振幅降低(p<0.05)。总唾液褪黑素浓度显著低于iRBD（p<0.05），弱光褪黑激素的发作有轻微但不明显的相位延迟。
结论：这项探索性研究强调了iRBD中昼夜节律睡眠-觉醒节律的失调以及褪黑激素分泌的减少。未来的研究可能会增加这些初步发现，以评估调节睡眠-觉醒周期的新治疗方法，并阐明昼夜节律失调在从iRBD转变为神经变性中的意义。
方法：诊断为iRBD和HC的参与者接受了临床评估，并佩戴了7个昼夜的活动记录仪。在记录的最后一个晚上的五个时间点测量唾液褪黑素浓度。对临床数据进行了比较分析，活动参数，和褪黑激素水平在两组之间。
结果：iRBD参与者（n=18）表现出更大的运动（p<0.01）和非运动症状（p<0.001），与HC相比，昼夜节律睡眠-觉醒节律中断（n=10）。具体来说,肌动描记术显示延迟的中心相位测量(p<0.05)，在最活跃的时间内活动减少（p<0.001），相对振幅降低(p<0.05)。总唾液褪黑素浓度显著低于iRBD（p<0.05），弱光褪黑激素的发作有轻微但不明显的相位延迟。
结论：这项探索性研究强调了iRBD中昼夜节律睡眠-觉醒节律的失调以及褪黑激素分泌的减少。未来的研究可能会增加这些初步发现，以评估调节睡眠-觉醒周期的新治疗方法，并阐明昼夜节律失调在从iRBD转变为神经变性中的意义。
