Abstract-Masked hypertension, an elevated daytime ambulatory blood pressure in the presence of a normal office blood pressure, confers an increased cardiovascular risk to adults. We investigated the prevalence, persistence, and clinical significance of masked hypertension in children and adolescents. We enrolled 592 youths (6 to 18 years old). Youths with masked hypertension (nϭ34) and a random sample of the normotensive participants (nϭ200) were followed-up. In a nested case-control study, we compared echocardiographic left ventricular mass among cases with persistent masked hypertension and normotensive controls. At baseline, mean age was 10.2 years; 535 youths were normotensive on office and daytime ambulatory blood pressure measurement (90.4%), and 45 had masked hypertension (7.6%). Compared with normotensive controls, participants with masked hypertension had a higher ambulatory pulse rate, were more obese, and were 2.5-times more likely to have a parental history of hypertension. Among 34 patients with masked hypertension (median follow-up 37 months), 18 became normotensive, 13 had persistent masked hypertension, and 3 had sustained hypertension. Patients with persistent masked hypertension (nϭ17) or who progressed from masked to sustained hypertension (nϭ3) had a higher left ventricular mass index (34.9 versus 29.6 g/m 2.7 ; Pϭ0.023) and a higher percentage with left ventricular mass index above the 95th percentile (30% versus 0%; Pϭ0.014) than normotensive controls. In children and adolescents, masked hypertension is a precursor of sustained hypertension and left ventricular hypertrophy. This condition warrants follow-up and, once it becomes persistent, is an indication for blood pressure-lowering treatment.

Abstract-The objective was to analyze pulse wave velocity (PWV) in normotensive, high-normal, and hypertensive youths by using aortic-derived parameters from peripheral recordings. The impact of obesity on vascular phenotypes was also analyzed. A total of 501 whites from 8 to 18 years of age were included. The subjects were divided according to BP criteria: 424 (85%) were normotensive, 56 (11%) high-normal, and 21 (4%) hypertensive. Obesity was present in 284 (56%) and overweight in 138 (28%). Pulse wave analysis using a SphygmoCor device was performed to determine central blood pressure (BP), augmentation index, and measurement of PWV. Among the BP groups, differences appeared in age, sex, and height but not in body mass index. Significant differences in peripheral and central systolic and diastolic BPs and pulse pressures were observed within groups. A graded increase in PWV was present across the BP strata without differences in augmentation index. Using a multiple regression analysis, age, BP groups, and obesity status were independently associated with PWV. Older and hypertensive subjects had the highest PWV, whereas, from normal weight status to obesity, PWV decreased. Likewise, PWV was positively related to peripheral or central systolic BP and negatively related to body mass index z score. For 1 SD of peripheral systolic BP, PWV increased 0.329 m/s, and for 1 SD of body mass index z score PWV decreased 0.129 m/s. In conclusion, PWV is increased in hypertensive and even in high-normal children and adolescents. Furthermore, obesity, the factor most frequently related to essential hypertension in adolescents, blunted the expected increment in PWV of hypertensive and high-normal subjects. (Hypertension. 2012;60:550-555.)Key Words: hypertension Ⅲ obesity Ⅲ children Ⅲ adolescents Ⅲ augmentation index Ⅲ pulse wave velocity C ardiovascular damage occurring in adults finds its roots in risk factors operating early in life. Among the factors influencing cardiovascular risk, blood pressure (BP) values represent an important measurable marker of the level of potential cardiovascular risk in children and adolescents. The need to identify cardiovascular risk factors, including high BP, in youth, is acknowledged more and more frequently. Consequently, measurement of BP has become a routine part of pediatric care, and asymptomatic hypertension is now detected in pediatric care practice.BP phenotype is determined not only by conventional risk factors but also by weight gain in childhood. The adverse effects of excessive weight gain on BP and the association of weight gain with higher incidence of BP elevation represent major issues in health care.1-5 Elevation of systolic and/or diastolic BP indicates high BP in the child. In addition, children and adolescents with mild BP elevation, in the high-normal range, are much more common than was thought in the past, ranging from 3.4% to 15.7%. 6,7 Rather than having a goal of classifying children as high-normal, we should be identifying those who may be at risk for the developm...