Does adenotonsillectomy change vascular function in children with sleep breathing disorders?

睡眠呼吸障碍影响10%的儿童，严重时，上呼吸道阻塞会导致生长、发育、大脑功能和心脏健康的严重缺陷。但即使是轻微的打鼾（没有阻塞）也可能导致向大脑和心脏供血的动脉以及胳膊和腿上的小动脉的健康状况不佳。对于患有糖尿病和肥胖等疾病的成人和儿童来说，血管健康状况不佳会大大增加未来心脏病发作、心绞痛和中风的风险。患有严重睡眠呼吸障碍（如睡眠呼吸暂停综合症）的儿童目前的治疗方法是切除扁桃体和腺样体，这通常会解决打鼾问题并改善睡眠，但目前尚不清楚是否对血管健康有任何好处。儿童血管疾病的最早症状是血管内膜功能异常（内皮功能障碍）和血管内膜增厚（内膜中厚）。它们早于成年人的动脉粥样硬化疾病，动脉粥样硬化会导致心脏病和中风，以及糖尿病肾病和眼病。这些变化可以使用颈部和手臂动脉的超声成像准确且无创地测量。我们的主要目的是评估患有不同严重程度的睡眠呼吸障碍的儿童是否会发生血管健康的变化，次要目的是测量在两个睡眠期间（当打鼾发生时）心血管控制的任何变化。最重要的是，通过对儿童手术前后的评估，我们将能够首次看到儿童打鼾的治疗是否能改善血管健康。这项研究可能对打鼾儿童的临床管理有重大意义，这些儿童可能需要在更早的年龄进行治疗，以防止血管健康状况不佳，并在以后的生活中增加患心血管疾病的风险。

Sleep breathing disorders affect 10% of all children and when severe, obstruction in the upper airways causes serious deficits in growth, development, brain function and heart health. But even mild snoring (without obstruction) may also cause poor health in the arteries that supply blood to the brain and heart, as well as the smaller arteries in the arms and legs. In both adults and children with conditions like diabetes and obesity, poor blood vessel health has been shown to greatly increase the future risk of heart attacks, angina and strokes. Children with severe sleep breathing disorders (such as sleep apnoea syndrome) are currently treated by removal of the tonsils and adenoids, which typically resolves snoring and improves sleep, but it is not yet known whether there are any benefits for blood vessel health. The earliest signs of blood vessel disease in children are abnormal function of the lining of the blood vessels (endothelial dysfunction) and thickening of the lining of blood vessels (intima media thickness). They precede the adult diseases of atherosclerosis - which causes heart attacks and strokes, and diabetic kidney and eye disease. These changes can be measured accurately and non-invasively using ultrasound imaging of arteries in the neck and arm. Our primary aim is to assess whether changes in blood vessel health occur in children with sleep breathing disorders across the range of severity, with a secondary aim to measure any changes in cardiovascular control during both sleep (when snoring occurs). Most importantly, by assessing children before and after surgery, we will be able to see for the first time whether treatment of childhood snoring improves blood vessel health. This study may have major implications for the clinical management of snoring children, who may require treatment at an earlier age to prevent poor blood vessel health and an increased risk of cardiovascular diseases later in life.