Vascular Functions in Children with Sleep Disordered Breathing

描述(申请人提供)：儿童睡眠呼吸障碍综合征(SDB)包括单纯鼾症、阻塞性低通气性(OH)和不同程度的阻塞性睡眠呼吸暂停(OSA)。该综合征在所有儿童中的发生率超过12%，大多数儿童的严重程度在轻度至中度范围内。虽然严重的SDB的长期心血管后遗症已得到很好的认识，但那些继发于较轻形式的SDB的后遗症仍未确定。缺乏对不太严重的SDB的长期心血管发病率的了解，妨碍了对患有这种疾病的儿童进行适当的管理，并在成年期间预防心血管疾病。我们之前曾报道过一项新的观察，即SDB儿童的左心室重构和肥厚独立于持续性高血压和肥胖发生。然而，左心室重构的机制尚不清楚。我们提供了SDB儿童的新的初步数据，显示急性时相反应物的血浆水平与左心室重量之间有很强的相关性。此外，我们首次提供了有趣的初步数据，表明与对照组相比，患有SDB的瘦和肥胖儿童的颈动脉结构和功能发生了变化，收缩压更高，脉压更宽。这项研究的目标有三个：1)比较患有不同程度SDB的5-13岁儿童和正常对照组的炎性心血管疾病机制；2)确定血浆细胞因子水平与扁桃体中细胞因子水平的关系；3)研究炎症标志物与预后重要的心血管指标的关系，如颈动脉内膜厚度、颈动脉顺应性、脉压、主动脉僵硬和左心室质量和功能。

DESCRIPTION (provided by applicant): The pediatric syndrome of sleep disordered breathing (SDB) encompasses children with simple snoring, obstructive hypoventilation (OH), and varying degrees of obstructive sleep apnea (OSA). The syndrome occurs in more than 12% of all children, with most falling within the mild to moderate range of the severity spectrum. Although the long-term cardiovascular sequelae of severe SDB are well recognized, those that develop secondary to milder forms of SDB remain undefined. The lack of knowledge regarding the long-term cardiovascular morbidity of less severe forms of SDB precludes adequate management of children with the disorder and prevention of cardiovascular disease during adulthood. We have previously reported a novel observation that left ventricular remodeling and hypertrophy in children with SDB occurs independently of sustained hypertension and obesity. The mechanism of left ventricular remodeling however remains undefined. We present novel preliminary data in children with SDB showing a strong association between plasma level of acute phase reactants and left ventricular mass. Moreover, we present intriguing preliminary data demonstrating for the first time that compared to controls, lean and obese children with SDB have structural and functional changes of the carotid artery, higher systolic blood pressure and wider pulse pressure. All are important indicators of blood vessel stiffness and determinants of left ventricular load and mass.The goals of this study are threefold: 1) to compare inflammatory cardiovascular disease mechanisms in 5- to 13-year-old children with varying degrees of SDB to those in normal controls; 2) to determine how cytokine levels in plasma relate to those in tonsils; 3) to examine the relationship between inflammatory markers and prognostically important cardiovascular measures such as carotid intima thickness, carotid compliance, pulse pressure, aortic stiffness and left ventricular mass and function before and after adenotonsillectomy.