ANTENATAL STEROID EXPOSURE AND BLOOD PRESSURE IN CHILDHOOD

我们假设极低出生体重儿（VLBW; 1501 g）产前暴露于糖皮质激素（ANCS） 与14岁时血压升高有关。ANCS通常用于预期怀孕的母亲 来提高早产儿的存活率。然而，ANCS与升高的 14岁时的血压。儿童期血压与成年期血压相关， 后者影响心血管疾病发病率的风险。在极低出生体重婴儿中， 暴露于ANCS的风险很高;因此，拟议的研究与重大的公共卫生问题有关。 动物研究表明，ANCS与成年期血压升高之间存在联系， ANCS可能通过降低肾素-血管紧张素系统的活性改变发育中的肾脏和大脑 （RAS）。这些改变导致肾脏结构和功能的终身变化以及心血管控制的改变， 使成年人易患高血压。 拟议研究的对象是1992-1995年出生的单胎VLBW儿童，在我们的 重症监护室，并在我们的门诊新生儿随访诊所随访至一岁调整年龄。在 该样本ANCS暴露频率为47%。我们建议测量以下内容：1）静息血液 在儿童14岁生日后一年的3次访视时测量血压、身高和体重，2）动态血压，3） 血压对运动和冷应激的反应，4）心率变异性，5）唾液皮质醇，6）健身水平， 身体活动，7）使用DXA扫描的身体组成，8）微量白蛋白尿，9）尿液中RAS的元素， 血液和10）估计的肾小球滤过率。经调整的围产期接触和一年内生长数据 年龄将从医疗记录和计算机化数据库中获得。多变量分析将用于估计 暴露于ANCS的儿童与未暴露于ANCS的儿童之间的血压差异，调整 潜在的混杂因素和一些已知的血压相关因素。

We hypothesize that exposure to antenatal glucocorticoids (ANCS) in very low birth weight (VLBW;1501g) infants is associated with elevated blood pressure at 14 years of age. ANCS are frequently given to mothers who are expected to deliver prematurely to improve survival of premature infants. However, ANCS have been associated with elevated blood pressure at 14 years of age. Childhood blood pressure is correlated with blood pressure in adulthood, and the latter influences the risk of cardiovascular morbidity. Among VLBW babies, both the survival rate and the rate of exposure to ANCS are high; thus, the proposed research is pertinent to a significant public health concern. Supporting the proposed link between ANCS and elevated blood pressure in adulthood, animals studies indicate that ANCS alter the developing kidney and brain, possibly by decreasing the activity of the renin-angiotensin system (RAS). These alterations lead to lifelong changes in kidney structure and function and altered cardiovascular control, predisposing the adult to hypertension. The subjects for the proposed study are VLBW children who were singleton births, born 1992-1995, cared for in our intensive care nurseries, and followed in our out-patient neonatal follow up clinic through one year adjusted age. In this sample the frequency of ANCS exposure is 47%. We propose measurements of the following: 1) resting blood pressure, height, and weight, at 3 visits in the year after the child's fourteenth birthday, 2) ambulatory blood pressure, 3) blood pressure response to exercise and cold stress, 4) heart rate variability, 5) salivary cortisol, 6) level of fitness and physical activity, 7) body composition using DXA scans, 8) microalbuminuria, 9) elements of the RAS in the urine and blood, and 10) estimated glomerular filtration rate. Data on perinatal exposures and growth through one year adjusted age will be obtained from medical records and a computerized database. Multivariate analyses will be used to estimate the difference in blood pressure between children exposed to ANCS and those not exposed to ANCS, adjusting for potential confounders and a number of known correlates of blood pressure.