Department of General Psychology, University of Padova,Padua, Italy.
Clin Auton Res. 2013 Feb;23(1):49-56. doi: 10.1007/s10286-012-0178-2. Epub 2012 Sep 14.
A growing literature supports the association between insomnia and cardiovascular risk. Since only few studies have provided empirical evidence of hyper-activation of the cardiovascular system in insomniacs, the aim of the present study was to analyze cardiac autonomic responses in primary insomnia.
Impedance cardiography and heart rate variability (HRV) measures were assessed in 9 insomniacs and 9 good sleepers during a night of polysomnographic recording.
Insomniacs were found to be characterized by a constant sympathetic hyper-activation which was maintained all night, as suggested by a faster pre-ejection period (PEP) compared to good sleepers. In addition, only insomniacs showed a strong reduction in heart rate in the transition from wake to sleep. Both groups exhibited a reduction in cardiac output and sympathovagal balance, i.e., reductions in low-frequency/high-frequency ratio and increases in high-frequency normalized units of HRV, across the night. In addition, in our sample, a high physiological sympathetic activation (fast PEP) at night was found to be directly associated with low quality of sleep.
These preliminary findings suggest that a constant cardiac sympathetic hyper-activation throughout the night is a main feature of primary insomnia. Our evidences support the association between insomnia and increased risk for cardiovascular diseases.
越来越多的文献支持失眠与心血管风险之间存在关联。由于只有少数研究提供了失眠症患者心血管系统过度激活的经验证据，因此本研究旨在分析原发性失眠症的心脏自主神经反应。
在一夜多导睡眠记录期间，通过阻抗心动描记术和心率变异性（HRV）测量评估了 9 例失眠症患者和 9 例睡眠良好者的情况。
与睡眠良好者相比，失眠症患者被发现表现出持续的交感神经过度激活，这表明其射前期（PEP）更快。此外，只有失眠症患者在从清醒到睡眠的过渡中表现出心率的大幅下降。两组在夜间均表现出心输出量和交感神经迷走神经平衡的降低，即低频/高频比降低，HRV 的高频归一化单位增加。此外，在我们的样本中，夜间高生理交感神经激活（快速 PEP）与睡眠质量低直接相关。
这些初步发现表明，整夜持续的心脏交感神经过度激活是原发性失眠症的一个主要特征。我们的证据支持失眠症与心血管疾病风险增加之间的关联。
