Horne Rosemary S C, Sakthiakumaran Ashwini, Bassam Ahmad, Thacker Julie, Walter Lisa M, Davey Margot J, Nixon Gillian M
The Ritchie Centre, Department of Paediatrics, Monash University and Hudson Institute of Medical Research, Melbourne, VIC, Australia.
Melbourne Children's Sleep Centre, Monash Children's Hospital, Melbourne, VIC, Australia.
Pediatr Res. 2021 Oct;90(4):819-825. doi: 10.1038/s41390-020-01285-6. Epub 2020 Nov 23.
Sleep disordered breathing (SDB) in typically developing (TD) children is associated with adverse cardiovascular effects. As children with Down syndrome (DS) are at increased risk for SDB, we aimed to compare the cardiovascular effects of SDB in children with DS to those of TD children with and without SDB.
Forty-four children with DS (3-19 years) were age and sex matched with 44 TD children without SDB (TD-) and with 44 TD children with matched severity of SDB (TD+). Power spectral density was calculated from ECG recordings, for low frequency (LF), high frequency (HF), total power and the LF/HF ratio.
Children with DS had lower HF power, and higher LF/HF during sleep and when awake. There were no differences between groups for LF power. SpO nadir, average SpO drop and SpO > 4% drop were larger in the DS group compared to the TD+ group (p < 0.05 for all).
Our findings demonstrate significantly reduced parasympathetic activity (reduced HF power) and increased LF/HF (a measure of sympathovagal balance) in children with DS, together with greater exposure to hypoxia, suggesting SDB has a greater effect in these children that may contribute to an increased risk of adverse cardiovascular outcomes.
Sleep disordered breathing in children with Down syndrome exacerbates impaired autonomic control and increases exposure to hypoxia, compared to typically developing children. In typically developing children sleep disordered breathing has adverse effects on autonomic cardiovascular control. The prevalence of sleep disordered breathing is very high in children with Down syndrome; however, studies on the effects on cardiovascular control are limited in this population. This study supports screening and early treatment of sleep disordered breathing in children with Down syndrome.
在发育正常（TD）的儿童中，睡眠呼吸障碍（SDB）与不良心血管效应相关。由于唐氏综合征（DS）患儿患SDB的风险增加，我们旨在比较DS患儿中SDB的心血管效应与有和没有SDB的TD患儿的心血管效应。
44名DS患儿（3至19岁）在年龄和性别上与44名无SDB的TD患儿（TD-）以及44名SDB严重程度匹配的TD患儿（TD+）进行匹配。从心电图记录中计算出低频（LF）、高频（HF）、总功率和LF/HF比值的功率谱密度。
DS患儿在睡眠和清醒时HF功率较低，LF/HF较高。各组之间LF功率没有差异。与TD+组相比，DS组的SpO最低点、平均SpO下降和SpO下降>4%更大（所有p<0.05）。
我们的研究结果表明，DS患儿的副交感神经活动显著降低（HF功率降低），LF/HF升高（交感迷走神经平衡的一种测量指标），同时缺氧暴露增加，这表明SDB对这些患儿的影响更大，可能导致不良心血管结局的风险增加。
与发育正常的儿童相比，唐氏综合征患儿的睡眠呼吸障碍会加剧自主控制受损并增加缺氧暴露。在发育正常的儿童中，睡眠呼吸障碍对自主心血管控制有不良影响。唐氏综合征患儿中睡眠呼吸障碍的患病率非常高；然而，该人群中关于对心血管控制影响的研究有限。本研究支持对唐氏综合征患儿进行睡眠呼吸障碍的筛查和早期治疗。
