Vascular Functions in Children with Sleep Disorder Breathing

描述（由申请人提供）：儿童睡眠呼吸障碍综合征（SDB）包括单纯打鼾、阻塞性通气不足（OH）和不同程度的阻塞性睡眠呼吸暂停（OSA）的儿童。该综合征发生在超过12%的儿童中，大多数属于轻度至中度的严重程度范围。虽然严重SDB的长期心血管后遗症是公认的，但继发于轻度SDB的后遗症仍不明确。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的适当管理和成年期心血管疾病的预防。我们以前曾报道过一个新的观察结果，即SDB儿童的左心室重塑和肥厚独立于持续性高血压和肥胖。然而，左心室重构的机制仍不清楚。我们提出了新的初步数据，在SDB儿童显示急性期反应物的血浆水平和左心室质量之间有很强的关联。此外，我们提出了有趣的初步数据首次表明，与对照组相比，瘦和肥胖的SDB儿童的颈动脉的结构和功能的变化，更高的收缩压和更广泛的脉压。所有这些都是血管硬度的重要指标，也是左心室负荷和质量的决定因素。本研究的目的有三个：1）比较5- 13岁不同程度SDB儿童与正常对照儿童的炎症性心血管疾病机制; 2）确定血浆中细胞因子水平与扁桃体中细胞因子水平的关系;（3）研究扁桃体切除术前后炎症标志物与颈动脉内膜厚度、颈动脉顺应性、脉压、主动脉僵硬度、左心室质量和功能等重要心血管指标的关系。

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.