Cunningham Hannah A, Dovek Laura, Recoder Natasha, Bryant-Ekstrand Mohini D, Ligman Brittany R, Piantino Juan, Lim Miranda M, Elliott Jonathan E
bioRxiv. 2024 Sep 24:2024.09.20.614142. doi: 10.1101/2024.09.20.614142.
Individuals with comorbid REM sleep behavior disorder (RBD) and neurotrauma (defined by traumatic brain injury and post-traumatic stress disorder) have an earlier age of RBD symptom onset, increased RBD-related symptom severity and more neurological features indicative of prodromal synucleinopathy compared to RBD only. An early sign of neurodegenerative condition is autonomic dysfunction, which we sought to evaluate by examining heart rate variability during sleep. Participants with overnight polysomnography were recruited from the VA Portland Health Care System. Veterans without neurotrauma or RBD (controls; n=19), with RBD only (RBD, n=14), and with RBD and neurotrauma (RBD+NT, n=19) were evaluated. Eligible 5-minute NREM and REM epochs without apneas/hypopneas, microarousals, and ectopic beats were analyzed for frequency and time domain (e.g. low frequency power, LF; high frequency power, HF; root mean square of successive RR intervals, RMSSD; % of RR intervals that vary ≥50 ms, pNN50) heart rate variability outcomes. Heart rate did not significantly differ between groups in any sleep stage. Time domain and frequency domain variables (e.g., LF power, HF power, RMSSD, and pNN50) were significantly reduced in the RBD and RBD+NT groups compared to controls and RBD only during NREM sleep. There were no group differences detected during REM sleep. These data suggest significant reductions in heart rate variability during NREM sleep in RBD+NT participants, suggesting greater autonomic dysfunction compared to controls or RBD alone. Heart rate variability during sleep may be an early, promising biomarker, yielding mechanistic insight for diagnosis and prognosis of early neurodegeneration in this vulnerable population.
Comorbid REM sleep behavior disorder (RBD) and neurotrauma (NT, traumatic brain injury + post-traumatic stress disorder; RBD+NT) is associated with increased neurodegenerative symptom burden and worsened health. Sleep and autonomic function are integrally and bidirectionally related to neurodegenerative processes. In the current study, we sought to determine if early signs of autonomic dysfunction, measured via heart rate variability (HRV), were present during sleep in comorbid RBD+NT compared to RBD only and controls. Our data show reduced time and frequency domain HRV during NREM sleep in RBD+NT Veterans compared to RBD only and controls. These data contribute evidence that participants with RBD and comorbid NT demonstrate significantly worse autonomic dysfunction compared to age/sex matched participants with RBD alone.
与单纯快速眼动睡眠行为障碍（RBD）患者相比，患有共病性RBD和神经创伤（由创伤性脑损伤和创伤后应激障碍定义）的个体RBD症状出现的年龄更早，RBD相关症状严重程度增加，且有更多提示前驱性突触核蛋白病的神经学特征。神经退行性疾病的一个早期迹象是自主神经功能障碍，我们试图通过检查睡眠期间的心率变异性来进行评估。从波特兰退伍军人医疗保健系统招募进行夜间多导睡眠图检查的参与者。对没有神经创伤或RBD的退伍军人（对照组；n = 19）、仅患有RBD的退伍军人（RBD组，n = 14）以及患有RBD和神经创伤的退伍军人（RBD + NT组，n = 19）进行评估。分析符合条件的5分钟非快速眼动（NREM）和快速眼动（REM）睡眠期，这些睡眠期无呼吸暂停/低通气、微觉醒和异位搏动，以获取心率变异性的频率和时域指标（例如低频功率，LF；高频功率，HF；连续RR间期的均方根，RMSSD；RR间期变化≥50 ms的百分比，pNN50）。在任何睡眠阶段，各组之间的心率均无显著差异。与对照组和仅患有RBD的组相比，RBD组和RBD + NT组在NREM睡眠期间时域和频域变量（例如LF功率、HF功率、RMSSD和pNN50）显著降低。在REM睡眠期间未检测到组间差异。这些数据表明，RBD + NT参与者在NREM睡眠期间心率变异性显著降低，这表明与对照组或单独的RBD患者相比，其自主神经功能障碍更严重。睡眠期间的心率变异性可能是一种早期且有前景的生物标志物，可为这一脆弱人群早期神经退行性变的诊断和预后提供机制性见解。
共病性RBD和神经创伤（NT，创伤性脑损伤 + 创伤后应激障碍；RBD + NT）与神经退行性症状负担增加和健康状况恶化相关。睡眠和自主神经功能与神经退行性过程密切相关且相互影响。在本研究中，我们试图确定与仅患有RBD的患者和对照组相比，通过心率变异性（HRV）测量的共病性RBD + NT患者在睡眠期间是否存在自主神经功能障碍的早期迹象。我们的数据显示，与仅患有RBD的退伍军人和对照组相比，RBD + NT退伍军人在NREM睡眠期间时域和频域HRV降低。这些数据证明，与年龄/性别匹配的仅患有RBD的参与者相比，患有RBD和共病性NT的参与者自主神经功能障碍明显更严重。
