Kontos Anna, Willoughby Scott, van den Heuvel Cameron, Kennedy Declan, Martin James, Hodge Greg, Worthley Matthew, Chin Adelene Kaihui, Nelson Adam, Teo Karen, Baumert Mathias, Pamula Yvonne, Lushington Kurt
Robinson Research Institute, University of Adelaide, 3rd Floor Norwich Building, 55 King William Street, North Adelaide, 5006, Australia.
Discipline of Paediatrics, School of Medicine, University of Adelaide, Adelaide, Australia.
Heart Vessels. 2018 May;33(5):537-548. doi: 10.1007/s00380-017-1090-4. Epub 2017 Nov 22.
Sleep-disordered breathing (SDB) is associated with cardiovascular disease and systemic inflammation in adults but this remains to be explored in children, especially in children with the most common form of SDB, i.e. primary snoring/mild SDB. This pilot study investigated the relationship between the cardiovascular function and inflammation in children with mild SDB. Nineteen participants aged 5-14 years underwent overnight polysomnography, cardiac magnetic resonance imaging (aortic blood flow velocity and left and right ventricular systolic function) and assessment for inflammatory markers (intracellular cytokine analysis of T cells by flow cytometry). Parents also completed the Sleep Disturbances Scale for Children (SDSC). Children with mild SDB exhibited increased ascending aortic peak systolic velocity compared to controls (SDB 119.95 m/s vs. control 101.49 m/s, p < 0.05). No significant group differences were observed for left and right ventricular ejection fraction or mean aortic blood flow velocity from either the ascending aorta or pulmonary artery. Children with mild SDB had increased inflammatory markers as demonstrated by elevated T cell interferon gamma (IFNγ) (SDB 52 ± 4% vs. control 25 ± 3% positive cells, p < 0.005) and tumour necrosis factor alpha (TNFα) (SDB 39 ± 4% vs. control 20 ± 2% positive cells, p < 0.005) expression from CD8 cells. A strong positive correlation was observed between ascending aorta peak blood flow velocity and both TNFα and IFNγ (TNFα, r = 0.54, p < 0.03; IFNγ, r = 0.63, p < 0.005, respectively). Polysomnography revealed that oxygen saturation (SaO) nadir was significantly lower in children with mild SDB compared to controls (SDB 92.3 ± 2.7% vs. control 94.4 ± 1.6%, p < 0.05). A lower SaO nadir was associated with an increased ascending aorta peak systolic velocity (r = - 0.48, p < 0.05). As well, both a lower SaO nadir and an increased ascending aorta peak systolic velocity were associated with higher SDSC Sleep-Disordered Breathing and Disorder of Initiating and Maintaining Sleep subscale scores but not the polysomnographic-derived Obstructive Apnea-Hypopnea Index. The finding of elevated ascending aortic peak systolic blood flow velocity and its association with increased inflammatory markers suggests that the profile of cardiovascular changes noted in adult SDB may also occur in children with mild SDB.
睡眠呼吸紊乱（SDB）在成人中与心血管疾病和全身炎症相关，但在儿童中仍有待探索，尤其是在患有最常见形式的SDB（即原发性打鼾/轻度SDB）的儿童中。这项初步研究调查了轻度SDB儿童的心血管功能与炎症之间的关系。19名年龄在5至14岁的参与者接受了夜间多导睡眠监测、心脏磁共振成像（主动脉血流速度以及左右心室收缩功能）以及炎症标志物评估（通过流式细胞术对T细胞进行细胞内细胞因子分析）。家长们还完成了儿童睡眠障碍量表（SDSC）。与对照组相比，轻度SDB儿童的升主动脉收缩期峰值速度增加（SDB组为119.95m/s，对照组为101.49m/s，p<0.05）。对于左、右心室射血分数或来自升主动脉或肺动脉的平均主动脉血流速度，未观察到显著的组间差异。轻度SDB儿童的炎症标志物增加，表现为CD8细胞中T细胞干扰素γ（IFNγ）升高（SDB组为52±4%阳性细胞，对照组为25±3%阳性细胞，p<0.005）以及肿瘤坏死因子α（TNFα）升高（SDB组为39±4%阳性细胞，对照组为20±2%阳性细胞，p<0.005）。观察到升主动脉峰值血流速度与TNFα和IFNγ均呈强正相关（TNFα，r = 0.54，p<0.03；IFNγ，r = 0.63，p<0.005）。多导睡眠监测显示，轻度SDB儿童的氧饱和度（SaO）最低点显著低于对照组（SDB组为92.3±2.7%，对照组为94.4±1.6%，p<0.05）。较低的SaO最低点与升主动脉收缩期峰值速度增加相关（r = -0.48，p<0.05）。此外，较低的SaO最低点和增加的升主动脉收缩期峰值速度均与较高的SDSC睡眠呼吸紊乱及入睡和维持睡眠障碍子量表得分相关，但与多导睡眠监测得出的阻塞性呼吸暂停低通气指数无关。升主动脉收缩期峰值血流速度升高及其与炎症标志物增加的关联这一发现表明，在成人SDB中所观察到的心血管变化特征在轻度SDB儿童中也可能出现。
