Ambulatory blood pressure monitoring in children and adolescents: recommendations for standard assessment: a scientific statement from the American Heart Association Atherosclerosis, Hypertension, and Obesity in Youth Committee of the council on cardiovascular disease in the young and the council for high blood pressure research

Metabolic abnormalities, cardiovascular disease risk factors, and GFR decline in children with chronic kidney disease

BACKGROUND AND OBJECTIVES

Metabolic abnormalities and cardiovascular disease (CVD) risk factors have rarely been systematically assessed in children with chronic kidney disease (CKD). We examined the prevalence of various CKD sequelae across the GFR spectrum.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Data were used from 586 children participating in the Chronic Kidney Disease in Children (CKiD) study (United States and Canada) with GFR measured by iohexol plasma disappearance. Laboratory values and CVD risk factors were compared across GFR categories and with an age-, gender-, and race-matched community sample.

RESULTS

CKiD participants were 62% male, 66% Caucasian, 23% African American, and 15% Hispanic with a median age of 11 years and a median GFR of 44 ml/min per 1.73 m(2). Compared with those with a GFR ≥ 50 ml/min per 1.73 m(2), having a GFR < 30 ml/min per 1.73 m(2) was associated with a three-fold higher risk of acidosis and growth failure and a four- to five-fold higher risk of anemia and elevated potassium and phosphate. Median GFR change was -4.3 ml/min per 1.73 m(2) and -1.5 ml/min per 1.73 m(2) per year in children with glomerular and nonglomerular diagnoses, respectively. Despite medication and access to nephrology care, uncontrolled systolic hypertension was present in 14%, and 16% had left ventricular hypertrophy. Children with CKD frequently were also shorter and had lower birth weight, on average, compared with norms.

CONCLUSIONS

Growth failure, metabolic abnormalities, and CVD risk factors are present at GFR >50 ml/min per 1.73 m(2) in children with CKD and, despite therapy, increase in prevalence two- to four-fold with decreasing GFR.

Influence of physical activity on cardiorespiratory fitness in children after renal transplantation

BACKGROUND

Cardiorespiratory fitness is significantly reduced in children with end-stage renal disease. The role of renal transplantation in improving cardiorespiratory fitness has not been thoroughly investigated.

METHODS

In this work, we wanted to assess whether, in children after a successful renal transplant, the amount of weekly physical exercise affects cardiorespiratory fitness and left ventricular mass (LVM). The study was conducted on 16 children after renal transplantation and 36 matching healthy controls. Four groups were formed according to the weekly amount of physical exercise; all children received an echocardiogram and underwent a treadmill exercise test according to the Bruce protocol.

RESULTS

Cardiorespiratory fitness is worst in renal transplant children with a weekly physical exercise<3 h; renal transplant children with a physical exercise of 3-5 h per week attain a cardiorespiratory fitness comparable to controls with a sedentary lifestyle (<3-h exercise per week); healthy controls with a weekly physical exercise of 3-5 h per week show the highest levels of cardiorespiratory fitness; the LVM assessed via echocardiography follows the same pattern.

CONCLUSIONS

In children with a successful renal transplant, a weekly physical exercise of 3-5 h significantly improves the cardiorespiratory fitness and the LVM, up to the level of matching healthy controls with a sedentary lifestyle (<3 h exercise per week).

Relationship of aortic pulse wave velocity and baroreceptor reflex sensitivity to blood pressure control in patients with repaired coarctation of the aorta

BACKGROUND

Increased aortic stiffness and reduced baroreceptor reflex sensitivity have been described independently after coarctation of the aorta (CoA) repair. This study sought to determine the relationship between these variables and blood pressure control in adolescents after early CoA repair.

METHODS

Spontaneous baroreceptor reflex sensitivity (sBRS) and aortic pulse wave velocity (PWV) were measured in 29 adolescents after CoA repair and compared with 20 age-matched controls. Patients treated for hypertension or having residual aortic narrowing were excluded. Ambulatory blood pressure (ABP), heart rate variability, and cardiac output were also recorded. After ABP measurement, CoA subjects were classified as normotensive or hypertensive.

RESULTS

Nine patients (31%) were hypertensive according to standard definitions, and this subgroup had higher aortic PWV than the normotensive subgroup (P = .004). There was a significant positive correlation between ABP and PWV seen in the whole CoA group (r(2) = 0.5, P < .01). The normotensive subgroup had increased sBRS compared with controls (P = .02). This difference was not seen between the hypertensive subgroup and controls. There was a significant inverse relationship between sBRS and aortic PWV in the whole CoA group (r(2) = 0.25, P = .01). The normotensive subgroup had a significant reduction in stroke index compared with controls (P = .02), which was not seen in the hypertensive subgroup (P = .96).

CONCLUSIONS

Adolescents with hypertension after CoA repair have increased aortic PWV and a relative reduction in sBRS compared with normotensive CoA patients. Thus, failure of the baroreceptor reflex to compensate for increasing arterial stiffness may herald the onset of hypertension in these patients.

Primary hypertension and special aspects of hypertension in older children and adolescents

The prevalence of hypertension has increased at an accelerated rate in older children and adolescents. This has raised great concern about premature development of cardiovascular disease, which has major long-term health and financial implications. While obesity and sedentary habits largely explain this phenomenon, there are other social and cultural influences that may unmask genetic susceptibility to hypertension in the pediatric population. While it is essential to exclude numerous causes of secondary hypertension in every child, these disorders are not discussed in this review. Rather, the aim of this review is to familiarize pediatricians with casual and ambulatory blood pressure measurement, epidemiology, pathophysiology, and management of several common conditions that play a role in the development of hypertension in children and adolescents. Besides primary hypertension and obesity-related hypertension, emphasis is given to epidemiology, measurement of blood pressure, including ambulatory blood pressure monitoring, hypertension associated with drug use, teenage pregnancy, and video and computer games. Lastly, because pediatricians are increasingly confronted with special issues concerning the management of the hypertensive athlete, this topic is also addressed.

Childhood obesity and cardiovascular disease

Childhood obesity has reached epidemic proportions. Many of these children have risk factors for later disease, including cardiovascular disease. For optimal cardiovascular health, health care professionals must be able to identify children and youth at risk and provide appropriate support as needed. The present article reviews the current medical literature on obesity and cardiovascular disease risk factors in the paediatric population, the long-term cardiovascular consequences of childhood obesity and the importance of early life. Recommendations promoting optimal cardiovascular health in all children and youth are discussed.

Casual blood pressure and neurocognitive function in children with chronic kidney disease: a report of the children with chronic kidney disease cohort study

BACKGROUND AND OBJECTIVES

Children with chronic kidney disease (CKD) are at risk for cognitive dysfunction, and over half have hypertension. Data on the potential contribution of hypertension to CKD-associated neurocognitive deficits in children are limited. Our objective was to determine whether children with CKD and elevated BP (EBP) had decreased performance on neurocognitive testing compared with children with CKD and normal BP.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This was a cross-sectional analysis of the relation between auscultatory BP and neurocognitive test performance in children 6 to 17 years enrolled in the Chronic Kidney Disease in Children (CKiD) project.

RESULTS

Of 383 subjects, 132 (34%) had EBP (systolic BP and/or diastolic BP ≥90(th) percentile). Subjects with EBP had lower mean (SD) scores on Wechsler Abbreviated Scales of Intelligence (WASI) Performance IQ than those with normal BP (normal BP versus EBP, 96.1 (16.7) versus 92.4 (14.9), P = 0.03) and WASI Full Scale IQ (97.0 (16.2) versus 93.4 (16.5), P = 0.04). BP index (subject's BP/95(th) percentile BP) correlated inversely with Performance IQ score (systolic, r = -0.13, P = 0.01; diastolic, r = -0.19, P < 0.001). On multivariate analysis, the association between lower Performance IQ score and increased BP remained significant after controlling for demographic and disease-related variables (EBP, β = -3.7, 95% confidence interval [CI]: -7.3 to -0.06; systolic BP index, β = -1.16 to 95% CI: -2.1, -0.21; diastolic BP index, β = -1.17, 95% CI: -1.8 to -0.55).

CONCLUSIONS

Higher BP was independently associated with decreased WASI Performance IQ scores in children with mild-to-moderate CKD.

Frequency of Familial Hyperaldosteronism Type 1 in a Hypertensive Pediatric Population

Familial hyperaldosteronism type 1 is an autosomal dominant disorder attributed to a chimeric CYP11B1/CYP11B2 gene (CG). Its prevalence and manifestation in the pediatric population has not been established. We aimed to investigate the prevalence of familial hyperaldosteronism type 1 in Chilean hypertensive children and to describe their clinical and biochemical characteristics. We studied 130 untreated hypertensive children (4 to 16 years old). Blood samples for measuring plasma potassium, serum aldosterone, plasma renin activity, aldosterone/renin ratio, and DNA were collected. The detection of CG was performed using long-extension PCR. We found 4 (3.08%) of 130 children with CG who belonged to 4 unrelated families. The 4 patients with CG had very high aldosterone/renin ratio (49 to 242). In addition, we found 4 children and 5 adults who were affected among 21 first-degree relatives. Of the 8 affected children, 6 presented severe hypertension, 1 presented prehypertension, and 1 presented normotension. High serum aldosterone levels (>17.7 ng/dL) were detected in 6 of 8 subjects (range: 18.6 to 48.4 ng/dL) and suppressed plasma renin activity (≤0.5 ng/mL per hour) and high aldosterone/renin ratio (>10) in 8 of 8 children (range: 49 to 242). Hypokalemia was observed in only 1 of 8 children. We demonstrated that the prevalence of familial hyperaldosteronism type 1 in a pediatric hypertensive pediatric population was surprisingly high. We found a high variability in the clinical and biochemical characteristics of the affected patients, which suggests that familial hyperaldosteronism type 1 is a heterogeneous disease with a wide spectrum of presentations even within the same family group.

Hypertension impairs vascular reactivity in the pediatric brain

BACKGROUND AND PURPOSE

Chronic hypertension impairs cerebrovascular regulation in adults, but its effects on the pediatric population are unknown. The objective of this study was to investigate cerebrovascular abnormalities in hypertensive children and adolescents.

METHODS

Sixty-four children and adolescents aged 7 to 20 years underwent transcranial Doppler examinations of the middle cerebral artery at the time of rebreathing CO2. Time-averaged maximum mean cerebral blood flow velocity and end-tidal CO2 were used to quantify cerebrovascular reactivity during hypercapnia. Patients were clinically categorized as hypertensive, prehypertensive, or white coat hypertensive based on 24-hour ambulatory blood pressure measurements. Their reactivities were compared with 9 normotensive control subjects and evaluated against baseline mean blood pressure z-scores and loads.

RESULTS

Untreated hypertensive children had significantly lower hypercapnic reactivity than normotensive children (2.556 +/- 1.832 cm/s x mm Hg versus 4.256 +/- 1.334 cm/s x mm Hg, P < 0.05). Baseline mean diastolic blood pressure z-scores (r = -0.331, P = 0.037) and diastolic blood pressure loads (r = -0.351, P = 0.026) were inversely related to reactivity.

CONCLUSIONS

Untreated hypertensive children and adolescents have blunted reactivity to hypercapnia, indicating deranged vasodilatory reactivity. The inverse relationship between diastolic blood pressure indices and reactivity suggests that diastolic blood pressure may be a better predictor of cerebral end organ damage than systolic blood pressure.

Poor sleep and cardiovascular function in children

We investigated whether sleep quantity and quality were related to 24-hour ambulatory blood pressure and cardiovascular reactivity in children. We studied term-born, healthy 8.0-year olds (SD: 1.4 years) without sleep-disordered breathing (231 and 265 children provided valid data for analyses of ambulatory blood pressure and cardiovascular reactivity, respectively). Sleep was registered with an actigraph for 6 nights on average (SD: 1.2; range: 3 to 13 nights). Ambulatory blood pressure was measured for 24-hours (41% nonschool days) with an oscillometric device. The children underwent the Trier Social Stress Test for Children, during which blood pressure, electrocardiography, and thoracic impedance were recorded and processed offline to give measures of cardiovascular and autonomic function. Neither quantity nor quality of sleep was related to 24-hour ambulatory blood pressure or cardiovascular reactivity after accounting for major covariates (sex, age, height, body mass index, and parental education). Although lower sympathetic nervous system activation and higher cardiac activation under stress were found in the group of children who slept for short duration when they were compared with the average sleep duration group, these associations were not significant after correction for multiple testing and were not seen in linear regression models of the effects of sleep duration. These findings do not support the mainstream of epidemiological findings, derived from samples more heterogeneous in age, sociodemographic characteristics, and health, suggesting that poor sleep is associated with an unhealthy cardiovascular phenotype.

Impact of Stress Reduction Interventions on Hostility and Ambulatory Systolic Blood Pressure in African American Adolescents

This study examined the impact of breathing awareness meditation (BAM), life skills (LS) training, and health education (HE) interventions on self-reported hostility and 24-hour ambulatory blood pressure (ABP) in 121 African American (AA) ninth graders at increased risk for development of essential hypertension. They were randomly assigned to BAM, LS, or HE and engaged in intervention sessions during health class for 3 months. Before, after, and 3 months following intervention cessation, self-reported hostility and 24-hour ABP were measured. Results indicated that between pre- and postintervention, BAM participants displayed significant reductions in self-reported hostility and 24-hour systolic ABP. Reductions in hostility were significantly related to reductions in 24-hour systolic ABP. Between postintervention and follow-up, participants receiving LS showed a significant reduction in hostility but not in 24-hour ABP. Significant changes were not found for the HE group in 24-hour ABP or self-reported hostility, but these change scores were significantly correlated. The implications of the findings are discussed with regard to behavioral stress reduction programs for the physical and emotional health of AAs.

Relationships between renin, aldosterone, and 24-hour ambulatory blood pressure in obese adolescents

Renin-angiotensin system (RAS) activation and abnormalities of ambulatory blood pressure (ABP) are present in obesity, but relationships between components of the RAS and ABP have not been defined in the young. Anthropometric measurements and 24-h ABP were obtained on 30 obese adolescents with and without type 2 diabetes mellitus. Plasma renin activity (PRA), aldosterone, and other cardiovascular risk factors were measured. Median PRA levels were 2.5 [interquartile range (IQR), 1.7-4.1] ng/mL/h and were higher in the diabetic subjects compared with the nondiabetics. Females had significantly higher PRA than males 3.2 (IQR, 2-4.8) versus 1.8 (IQR, 1.1-2.9) ng/mL/h (p = 0.04) and were more obese. BMI Z score and PRA were significantly correlated (rho = 0.46, p < 0.001). PRA inversely correlated with 24-h systolic ABP (rho = -0.46, p = 0.02) and strongly with 24-h pulse pressure (rho = -0.61, p = 0.001). Aldosterone levels were also correlated with 24-h pulse pressure (rho = -0.46, p = 0.02). In multivariate models, lower PRA was independently associated with 24-h systolic blood pressure. In this study, PRA was positively correlated with BMI, but the relationships between components of the RAS and ABP were inverse. Further studies are needed to define the pathophysiologic relationship between RAS components and blood pressure regulation in obese youth.

Office, ambulatory and home blood pressure measurement in children and adolescents

There is an increasing interest in pediatric hypertension, the prevalence of which is rising in parallel with the obesity epidemic. Traditionally the assessment of hypertension in children has relied on office blood pressure (BP) measurements by the physician. However, as in adults, office BP might be misleading in children mainly due to the white coat and masked hypertension phenomena. Thus, out-of-office BP assessment, using ambulatory or home monitoring, has gained ground for the accurate diagnosis of hypertension and decision-making. Ambulatory monitoring is regarded as indispensable for the evaluation of pediatric hypertension. Preliminary data support the usefulness of home monitoring, yet more evidence is needed. Office, ambulatory and home BP normalcy tables providing thresholds for diagnosis have been published and should be used for the assessment of elevated BP in children.

Relationship of home blood pressure with target-organ damage in children and adolescents

The objective of this study was to compare home blood pressure (HBP) vs. ambulatory (ABP) and clinic (CBP) measurements in terms of their association with target-organ damage in children and adolescents. A total of 81 children and adolescents (mean age 13 ± 3 years, 53 boys) referred for elevated CBP had measurements of CBP (1 visit), HBP (6 days) and ABP (24-h). Seventy-six participants were also assessed with carotid-femoral pulse wave velocity (PWV) and 54 with echocardiography. Average CBP was 122.1 ± 15.1/71 ± 12.9 mm Hg (systolic/diastolic), HBP 121.3 ± 11.5/69.4 ± 6.6 mm Hg and 24-h ABP 118.9 ± 12/66.6 ± 6.1 mm Hg. Left ventricular mass (LVM) was correlated with systolic blood pressure (BP) (coefficient r = 0.55/0.54/0.45 for 24-h/daytime/nighttime ABP, 0.53 for HBP and 0.41 for CBP; all P< 0.01). No significant correlations were found for diastolic BP. PWV was also significantly correlated with systolic BP (r = 0.52/0.50/0.48 for 24-h/daytime/nighttime ABP, 0.50 for HBP and 0.47 for CBP; all P < 0.01). Only diastolic ABP and HBP were significantly correlated with PWV (r = 0.30 and 0.28, respectively, P<0.05). In multivariate stepwise regression analysis (with age, gender, body mass index [BMI], clinic, home and 24-h ambulatory systolic/diastolic BP and pulse pressure, clinic, home and 24-h heart rate as independent variables), PWV was best predicted by systolic HBP (R(2) = 0.22, beta ± s.e. = 0.06 ± 0.01), whereas LVM was determined (R(2) = 0.67) by 24-h pulse pressure (beta = 1.21 ± 0.41), age (beta = 2.93 ± 1.32), 24-h heart rate (beta = -1.27 ± 0.41) and BMI (beta = 1.78 ± 0.70). These data suggest that, in children and adolescents, ABP as well as HBP measurements appear to be superior to the conventional CBP measurements in predicting the presence of subclinical end-organ damage.

Underrecognition of elevated blood pressure readings in children after early repair of coarctation of the aorta

Hypertension after repair of coarctation of the aorta (CoA) is the outcome variable most closely associated with adverse long-term events such as stroke and myocardial infarction. This study sought to evaluate the outpatient management of casual blood pressure (BP) measurements in young children after early repair of CoA. A retrospective analysis was performed of clinical findings, echocardiographic data, casual BP recordings, and subsequent BP management of 114 children with CoA repair aged 1-13 years during 338 outpatient visits managed at two congenital cardiac centers. Children with associated significant congenital heart disease or corrective surgery after the age of 6 months were excluded from the study. Blood pressure was documented at 233 clinic visits (69%), and systolic BP (SBP) was above 95th percentile for age and sex in 45 instances (19%). This represented an elevated SBP recording for 31 children (27%), with two or more successive elevated recordings for 11 children (10%). Of 12 subjects receiving antihypertensive medication, three had inadequate BP control. Blood pressure is not documented at approximately 30% of outpatient visits of children with repaired CoA. When elevated BP is documented, in all cases no recorded action was taken. This may have significant implications for cardiovascular outcomes in this cohort of patients.

Role of twenty-four-hour ambulatory blood pressure monitoring in children on dialysis

BACKGROUND AND OBJECTIVES

Pre- or postdialysis BP recordings are imprecise, can be biased, and have poor test-retest reliability in children on dialysis. We aimed to examine the possible differences between pre- and postdialysis BP levels and 24-hour ambulatory BP monitoring (ABPM) in diagnosis of hypertension (HTN).

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Twenty-four children on dialysis had 24-hour ABPM in the interdialytic period, and values were compared with average pre- and postdialysis systolic BP (SBP) and diastolic BP (DBP) recordings that week. Each patient had an echocardiogram to determine presence of left ventricular hypertrophy (LVH).

RESULTS

By ABPM, 8% of patients had white coat HTN and 12% had masked HTN. There was no significant difference in diagnosis of systolic HTN based on ABPM daytime SBP mean or load and postdialysis SBP. However, only 15% of patients had diastolic HTN based on postdialysis measures, whereas 46% of patients had significantly elevated daytime DBP loads and 71% had high nighttime DBP loads on ABPM. Forty-eight percent of patients were SBP nondippers. Children with LVH had higher daytime and nighttime SBP loads, significantly higher daytime and nighttime DBP loads, and lesser degree of nocturnal dipping of SBP compared with those who did not.

CONCLUSION

ABPM is more informative than pre- and postdialysis BPs and improves the predictability of BP as a risk factor for target organ damage. Diagnosis and treatment monitoring of HTN among pediatric dialysis patients is enhanced with addition of ABPM.

Change in left ventricular geometry during antihypertensive treatment in children with primary hypertension

The pattern of the left ventricle (LV) has important significance in adults with hypertension. The aim of the present study was to analyze changes and determinants of LV geometry after 1 year of antihypertensive treatment in children with primary hypertension (PH) in relation to metabolic abnormalities and anthropometrical parameters. In 86 children (14.1 ± 2.4 years) with newly diagnosed PH, LV geometry and biochemical parameters before and after 12 months of standard antihypertensive therapy were assessed. At baseline, normal LV geometry (NG) was found in 42 (48.9%), concentric remodeling (CR) in 4 (4.6%), concentric hypertrophy (CH) in 8 (9.3%), and eccentric hypertrophy (EH) in 32 (37.2%) patients. The prevalence of NG in patients with severe hypertension was significantly lower than in patients with ambulatory hypertension. There were no differences in dipping status in relation to LV geometry. Patients with CH and EH were more viscerally obese than patients with NG. Patients with CH had higher diastolic blood pressure in comparison with EH patients (p < 0.05). The main predictor of relative wall thickness (RWT) was the triglycerides to high density lipoprotein cholesterol (TG/HDL) ratio (R(2 ) = 0.319, β = 0.246, p = 0.004). Patients received 12 months of antihypertensive treatment, either lifestyle modification only (n = 37) or lifestyle modification plus antihypertensive medications (n = 49) if severe ambulatory hypertension or target organ damage were present. After 12 months of treatment the prevalence of EH (37.2% vs 18.6%, p = 0.003) decreased but prevalence of CH did not change. Patients in whom RWT decreased also decreased waist circumference and TG/HDL; the main predictor of RWT decrease was a decrease of the TG/HDL ratio (β = 0.496, R (2) = 0.329, p = 0.002). In adolescents with PH, LV geometry is related to central obesity and insulin resistance. Decrease of abdominal obesity and insulin resistance are the most important predictors of normalization of LV geometry, however CH has lower potential to normalize LV geometry.

Ambulatory arterial stiffness index, pulse pressure and pulse wave velocity in children and adolescents

Arterial stiffness, assessed by carotid-femoral pulse wave velocity (PWV) or indirectly by pulse pressure (PP) or ambulatory arterial stiffness index (AASI), is an independent predictor of cardiovascular disease in adults. However, in children limited evidence is available. This study investigated the usefulness of AASI and PP as indices of arterial stiffness in children and adolescents, by taking PWV as the reference method. Eighty-two children and adolescents (mean age 13.1±2.9 years) had 24-h ambulatory blood pressure (ABP) monitoring, PWV measurement and echocardiography. Compared with normotensives, subjects with hypertension (n=16) had higher 24-h ABP, 24-h PP and PWV, but not AASI. 24-h, PP was strongly correlated with age, weight, height, 24-h systolic ABP, PWV, left ventricular mass (LVM), LVM index, stroke volume and inversely with 24-h heart rate. AASI was also correlated with weight, height, systolic ABP and LVM, yet these associations were weaker than those of PP, and no significant correlations were found with PWV or LVM index. Moreover, closer agreement of PWV was observed with 24-h PP (71%, kappa 0.21) than with 24-h AASI (61%, kappa -0.06) in detecting subjects at the top quartile of the respective distributions. In children and adolescents, 24-h PP compared with AASI appears to be more closely associated with: (i) arterial stiffness assessed by PWV; (ii) target organ damage assessed by LVM index; and (iii) the presence of essential hypertension. These data suggest that the usefulness of AASI as an index of arterial stiffness in the pediatric population is questionable.

Hypertension and obstructive sleep apnea in Caucasian children

AIM

To evaluate the prevalence of hypertension and/or left ventricular hypertrophy (LVH) in children with a diagnosis of obstructive sleep apnea (OSA).

METHODS

A cross-sectional case series of consecutive, otherwise healthy children aged > 4 years, with polysomnography-proven OSA [apnea hypopnea index (AHI) > 1.5/h] is described. Echocardiography was performed on all subjects and left ventricular mass was calculated. Study subjects underwent additional investigation with 24-h ambulatory blood pressure (BP) monitoring.

RESULTS

Thirty children (21 males) were studied. Mean age was 8.9 years. Mean body mass index was 19.87 kg/cm(2). Mean AHI was 14.3/h. 10/30 (33%) of the study population met criteria for pre-hypertension (n = 3) or masked hypertension (n = 7) based on standard ambulatory monitoring criteria. All 10 children had systolic hypertension throughout the night with 5 of these also having elevated daytime systolic readings. There was a relationship between AHI and BP showing an increase of 1.162 percentile units in mean diastolic night BP (age, gender and height specific) per unit increase in AHI (P = 0.018). There were no subjects with LVH and/or right ventricular hypertrophy.

CONCLUSION

In our population of otherwise healthy Caucasian children, there was a high prevalence of hypertension that would not have been identified using standard office/clinic protocols.

Improvement of left ventricular mass with antihypertensive therapy in children with hypertension

There is paucity of data on the regression of left ventricular hypertrophy (LVH) in hypertensive children. This study assessed the effects of antihypertensive therapy on left ventricular mass in children with and without LVH. Medical records of hypertensive patients who had a baseline and follow-up echocardiogram (echo 1, echo 2) were reviewed. Fifteen of 22 treated patients had LVH at echo 1. Enalapril alone or combined was used in 21/22 cases. Echo 2 was performed at a mean interval of 15 +/- 7 months. The LVH group showed significant decrease in systolic blood pressure z-score (SBPZ) (2.89 +/-1.61 to 1.40 +/- 1.19; p=0.01), diastolic blood pressure z-score (DBPZ) (1.44 +/- 0.90 to 0.26 +/- 0.82; p<0.001), and LV mass index (LVMI) (56.2 +/- 12.50 to 43.7 +/- 8.30; p=0.001), but no significant change in body mass index z-score (BMIZ) (1.79 +/- 0.75 to 1.69 +/- 0.69; p=0.74). In the no-LVH group, SBPZ (3.03 +/- 1.68 to 2.27 +/- 1.81; p=0.356), DBPZ (1.00 +/- 0.87 to 0.63 +/- 0.68; p=0.409), BMIZ (1.08 +/- 0.98 to 1.27 +/- 0.89; p=0.672), and LVMI (29.47 +/- 5.51 to 33.89 +/ -3.06;p=0.374) did not change significantly. Simple linear regression demonstrated that the change in LVMI in the combined group had a significant correlation (r=0.477; p=0.025) with the percentage change in SBPZ. This study demonstrates that LVH in hypertensive children improves with effective blood pressure control.

High blood pressure in children: clinical and health policy implications

Hypertension is a global problem, affecting both developed and developing nations. In addition to being a major cause of morbidity and mortality, hypertension places a heavy burden on health care systems, families, and society as a whole. Despite evidence of an increasing prevalence of hypertension among youth, the consequences of early onset are poorly established and often overlooked. Childhood hypertension is often asymptomatic and easily missed, even by health professionals. Target organ damage is detectable in children and adolescents, however, and hypertension continues into adulthood. Additional strategies to improve cardiovascular health among children and adolescents are needed, including methods to achieve healthy lifestyles at home and in school, improved systems for diagnosis, and research on mechanisms and timing of interventions. The burden of hypertension in the young will continue to grow unless it is given the attention it deserves by policy makers, health care providers, schools, parents, and society. This report aims to increase awareness of the problem of hypertension in childhood. Recent reports on prevalence and target organ injury are discussed and health policy initiatives to improve blood pressure control are proposed.

Ambulatory blood pressure before and after adenotonsillectomy in children with obstructive sleep apnea

INTRODUCTION

Hypertension is found to be associated with obstructive sleep apnea (OSA) in both children and adults. But data on the effect of blood pressure after adenotonsillectomy (AT) for children with OSA are limited and controversial.

OBJECTIVE

To assess the impact of AT on different parameters of 24-h ambulatory blood pressure monitoring in children with OSA.

METHODS

We retrospectively reviewed records of OSA children who had undergone AT and a repeated sleep polysomnography after AT from 2001 to 2008.

RESULTS

Forty-four children were identified and included in the analysis. The mean apnea-hypopnea index (AHI) dropped from 14.14+/-15.9 to 3.3+/-7.1. (p<0.001). Twenty (45%) were cured of OSA. After AT, the diastolic BP load decreased significantly. Six out of eight (75%) hypertensive children became normotensive after surgery. For the pre-AT hypertensive group, both systolic and diastolic blood pressure decreased significantly during sleep after AT. However, eight children who were normotensive before AT became hypertensive after AT. These 10 post-AT hypertensive patients were more likely to have post-AT AHI>1 than the post-AT normotensive group, although the difference did not reach statistical significance.

CONCLUSION

In the current cohort of OSA children, 44% were cured of OSA and a significant decrease in overall diastolic blood pressure load in 24-h ambulatory blood pressure was achieved after adenotonsillectomy for children with OSA. But hypertension may persist or even occur in those previously normotensive children despite the improvement in AHI. Persistence of OSA may be a risk factor and further study is required. Cure of OSA should not be assumed after AT and follow-up PSG should be performed together with 24-h ambulatory blood pressure monitoring. In light of the current findings, long term study of the blood pressure is warranted for children with OSA.

Predictors of left ventricular hypertrophy in children on chronic peritoneal dialysis

Conflicting results have been reported in small non-homogenous groups of children with chronic renal failure in terms of casual blood pressure and ambulatory blood pressure monitoring (ABPM) parameters and left ventricular hypertrophy (LVH). The aim of our study was to assess the value of ABPM and hematological and biochemical parameters in predicting LVH in children on chronic peritoneal dialysis (CPD). Echocardiography and 24-h ABPM were performed in addition to routine biochemical and hematological evaluations in 47 children on CPD (26 male, 21 female; mean age 14.74 +/- 3.52 years). Mean daytime systolic blood pressure (SBP) and mean daytime diastolic blood pressure (DBP) values were found to be higher than the mean casual SBP and DBP (p = 0.001) values. Thirty-three (70.2%) children had LVH. The correlations between the left ventricular mass index and ABPM variables were good. Stepwise multiple regression analysis revealed daytime SBP load (beta = 0.652; p < 0.01) and hematocrit (beta = -0.282; p < 0.01) to be independent predictors of LVH. The sensitivity, specificity, positive predictive value, and negative predictive values for the combination of the SBP load >15% and hematocrit value <31% for predicting LVH were 95 [95% confidence interval (CI) 76-99], 78 (95%CI 45-94), 91 (95%CI 73-98), and 88% (95%CI 69-96%), respectively. We conclude that: (1) LVH is prevalent in children on CPD, and (2) a target hematocrit level >31% and daytime SBP load <15% may be preventive for the progression of LVH in the follow-up of children on CPD.

Hypertension in children and adolescents: epidemiology and natural history

Primary hypertension is detectable in children and adolescents and, as in adults, is associated with a positive family history of hypertension, obesity, and life-style factors. Owing to the well-established childhood obesity epidemic, the population prevalence of high blood pressure (BP) in the young is increasing. Hypertension in childhood is commonly associated with other cardiovascular risk factors as well as obesity. Although death and cardiovascular disability do not occur in hypertensive children, intermediate markers of target organ damage, such as left ventricular hypertrophy, thickening of the carotid vessel wall, retinal vascular changes, and even subtle cognitive changes, are detectable in children and adolescents with high BP. Considering the rates of verified hypertension (>3%) and pre-hypertension (>3%) in asymptomatic children and adolescents, high BP should be considered a common long-term health problem in childhood.

Parental assessment of executive function and internalizing and externalizing behavior in primary hypertension after anti-hypertensive therapy

OBJECTIVE

To determine the change in parental ratings of executive function and behavior in children with primary hypertension after anti-hypertensive therapy.

STUDY DESIGN

Parents of subjects with untreated hypertension and control subjects completed the Behavior Rating Inventory of Executive Function (BRIEF) to assess behavioral correlates of executive function and the Child Behavior Checklist (CBCL) to assess internalizing and externalizing behaviors. Subjects with hypertension subsequently received anti-hypertensive therapy to achieve casual blood pressure (BP)<95th percentile. After 12 months, all parents again completed the BRIEF and CBCL.

RESULTS

Twenty-two subjects with hypertension and 25 normotensive control subjects underwent both baseline and 12-month assessments. The BP of subjects with hypertension improved (24-hour systolic BP [SBP] load: mean baseline versus 12-months, 60% versus 25%, P<.001). Parent ratings of executive function improved from baseline to 12 months in the subjects with hypertension (BRIEF Global Executive Composite T-score, Delta=-5.9, P=0.001), but not in the normotensive control subjects (Delta=-0.36, P=.83). In contrast, T-scores on the CBCL Internalizing and Externalizing summary scales did not change significantly from baseline to 12 months in either subjects with hypertension or control subjects.

CONCLUSIONS

Children with hypertension demonstrated improvement in parental ratings of executive function after 12 months of anti-hypertensive therapy.

Elevated ambulatory blood pressure in a multi-ethnic population of obese children and adolescents

OBJECTIVES

To evaluate the relationship among ambulatory blood pressure (ABP), body mass index (BMI), and homeostasis model assessment (HOMA) in a multi-ethnic population of obese children with clinic blood pressure in the reference range.

STUDY DESIGN

A total of 43 obese normotensive children (7-17 years old) were recruited. ABP monitoring, oral glucose tolerance test, lipid levels, and urine microalbumin levels were obtained.

RESULTS

Fourteen percent of the subjects had elevated 24-hour systolic blood pressure (SBP), 9.3% had elevated daytime SBP, and 32.6 % elevated nighttime SBP. For diastolic blood pressure, 4.7% of the sample had an elevated mean nighttime value. Children with more severe obesity (BMI SD score >2.5) had higher 24-hour and nighttime SBP than children with less severe obesity (BMI SD score < or =2.5). Children with HOMA values in the highest quartile had larger waist circumference and higher clinic blood pressure than children with HOMA values in the lowest quartile, and no difference in the mean ABP values was found in the 2 groups . Multiple linear regression analysis showed that 24-hour and nighttime SBP were significantly correlated with BMI SD score.

CONCLUSION

Obese children with normal clinic blood pressure often exhibit elevated ABP. The risk for ambulatory hypertension appears to be correlated with the degree of obesity.

Periodic limb movement during sleep is associated with nocturnal hypertension in children

BACKGROUND

Increasing evidence suggests that blood pressure (BP) is significantly influenced by sleep problems in children, but the association between periodic limb movement during sleep (PLMS) and BP is still unclear. This study aims to compare ambulatory blood pressure (ABP) in children with and without PLMS.

METHODS AND RESULTS

A cross-sectional study involving 314 children (mean (SD) age of 10.4 (1.7) years, boys 62.4%). Participants underwent an overnight polysomnographic study and ABP monitoring. Subjects were hypertensive if mean SBP or DBP > 95th percentile and prehypertensive if mean SBP or DBP > 90th percentile of reference. Children with PLMS (n = 17) were at significantly higher risk for nocturnal systolic (adjusted OR (95%CI) = 6.25 [1.87-20.88]) and diastolic (OR (95%CI) = 4.83 [1.66-14.07]) hypertension. However, mean nocturnal BP did not differ between children with and without PLMS. There was a trend for higher daytime BP in patients with PLMS than those children without PLMS (P = 0.084 for systolic BP z score; P = 0.051 for diastolic BP z score; P = 0.067 for systolic prehypertension). There were significant associations between log transformed PLM index and daytime systolic and mean BP z scores (P = 0.03 and 0.033 respectively) as well as that between log transformed PLM related arousal index (PLMSArI) and nocturnal diastolic and mean BP (P = 0.008 and 0.038 respectively).

CONCLUSIONS

PLMS was independently associated with a wide range of BP elevations, especially nocturnal indices. Future studies should examine the underlying pathophysiologic mechanisms and effects of PLMS treatment on BP.

Hypertension in children: new trends and challenges

Childhood HTN (hypertension) has become a widely investigated topic within the last decade due to its increasing prevalence. In the present review, we examine new developments and trends that have significantly contributed to aetiology, diagnosis, evaluation and management of childhood HTN. Many recent reports document an increasing prevalence of HTN, mainly essential HTN, in children worldwide. This is probably related to the increase of childhood obesity, although obesity is not the only factor. Evidence has been accumulating to suggest a rather complex interplay between obesity, uric acid level, dietary sodium intake, inflammation, inheritance and other factors, which lead to increased risk of developing HTN in childhood and adulthood. The detection and monitoring of HTN has significantly improved with the use of ABPM (ambulatory blood pressure monitoring), which allows not only for a more accurate classification and staging of HTN, but also for the calculation of more sophisticated parameters such as the AASI (ambulatory arterial stiffness index). Measurement of arterial stiffness enables assessment of arterial dysfunction, which may precede structural vascular changes evaluated by carotid intima media thickness. Sustained HTN eventually leads to end-organ damage [LVH (left ventricular hypertrophy), central nervous system], which in turn increases the risk of cardiovascular morbidity and mortality. New developments in childhood HTN, as outlined in the present review, will hopefully contribute to better screening and management of HTN in children.

Hypertension in adolescents

In adults, hypertension has long been perceived as a public health problem. By contrast, its impact in childhood is far less appreciated. In fact, quite often, high blood pressure in children is not even diagnosed. Blood pressure is a vital sign that is routinely obtained during a physical examination of adults, but only very seldom in children. The diagnosis of hypertension in children is complicated because 'normal' blood pressure values vary with age, sex and height. As a consequence, almost 75% of the cases of arterial hypertension and 90% of the cases of prehypertension in children and adolescents are currently undiagnosed. Furthermore, adolescence hypertension is increasing in prevalence as the prevalence of pediatric obesity has increased. Ambulatory blood pressure monitoring is a useful method for risk evaluation in adolescents. In addition to being viewed as an important cardiovascular risk factor in adolescents, elevated blood pressure should prompt a thorough search for other modifiable risk factors that, if treated, might reduce teenagers' risk of developing cardiovascular disease in adulthood. Thus, assessing blood pressure values in children represents one of the most important measurable markers of cardiovascular risk later in life and a major step in preventive medicine.

Hypertension after pediatric cardiac transplantation: detection, etiology, implications and management

While it may rescue children with end-stage heart failure from impending catastrophe, cardiac transplantation leaves 50-70% of pediatric recipients with new-onset hypertension. Given the unique vulnerability of the heart and kidneys in these children, we can expect long-term uncontrolled hypertension to shorten both graft and patient survival. In this review we discuss the multi-factorial etiology of post-transplant hypertension, highlighting current uncertainties and emphasizing mechanisms specific to cardiac recipients. We consider the optimal means of monitoring BP and in particular, the advantages of 24 h-ABP over intermittent clinic measurements. We also review BP treatment after cardiac transplantation, drawing attention to specific cautions appropriate when prescribing antihypertensive agents in these circumstances.

Hypertension in long-term survivors of childhood cancer: a nested case-control study

AIM OF THE STUDY

To examine risk factors for developing hypertension in childhood cancer survivors (CCS).

METHODS

We conducted a nested case-control study of risk for hypertension within a cohort of 1362 childhood cancer survivors treated between 1966 and 1996 in the Emma's Children's Hospital/Academic Medical Center in the Netherlands. Detailed information on treatment and several lifestyle factors was collected for 44 cases with hypertension and 123 matched controls. Odds ratios (ORs) for hypertension were calculated by conditional logistic regression analysis.

RESULTS

Body Mass Index (BMI) was the only significant risk factor associated with the occurrence of hypertension (OR 3.95; 95% confidence interval (CI) 1.7-9.1 for BMI25kg/m(2) compared to BMI<25kg/m(2)). However, cisplatin, cyclophosphamide and radiotherapy (RT) to the abdominal region were all associated with non-significant risk increases (ORs of 4.3, 2.1, and 1.8, respectively).

CONCLUSION

Our results show that BMI is the most important risk factor for hypertension following treatment of childhood cancer, emphasising the need for CCS to maintain a normal weight.

Genetic influences on daytime and night-time blood pressure: similarities and differences

OBJECTIVE

To examine whether the genetic influences on blood pressure (BP) during night-time are different from those during daytime and the extent to which they depend on ethnicity or sex.

METHODS

Ambulatory BP was measured in 240 European-American and 190 African-American twins (mean +/- SD age, 17.2 +/- 3.4). Individuals with night-time BP falls more than 10% of the daytime values were defined as dippers. A bivariate analysis of the daytime and the night-time BP levels, as well as a liability-threshold model of dippers vs. nondippers were used.

RESULTS

Bivariate model fitting showed no ethnic or sex differences for any of the measures, with heritabilities of 0.70 and 0.68 for SBP and 0.70 and 0.64 for DBP at daytime and at night-time. The genetic influences on daytime and night-time were not significantly different for SBP or DBP. The bivariate analysis also indicated that about 56 and 33% of the heritabilities of night-time SBP and DBP could be attributed to genes that also influenced daytime levels. The specific heritabilities due to genetic effects only influencing night-time values were 0.30 for SBP and 0.43 for DBP. The heritabilities of systolic and diastolic dipping were 0.59 and 0.81, respectively.

CONCLUSION

Independent of ethnicity and sex, an overlap exists between genes that influence daytime and night-time BP, as well as a significant genetic component that is specific to the night-time BP. These findings suggest that different genes or sets of genes contribute to BP regulation at daytime and night-time.

Assessment and management of hypertension in children and adolescents

The epidemic of overweight and obesity in youth is increasing the prevalence of prehypertension and hypertension among children and adolescents. The younger the child is at presentation and the more severe the blood pressure abnormality, the more likely a secondary cause of hypertension is to be present. Measurement of blood pressure in children requires adaptation to the age and size of the child. Interpretation must be related to normative values specific for age, sex, and height. Evaluation is primarily aimed at identifying secondary causes of hypertension, associated comorbidities, additional risk factors, and evidence of target-organ damage. Ambulatory blood pressure monitoring is emerging as a useful tool for evaluation of some patients, particularly for those with suspected 'white coat' hypertension. Management of prehypertension and hypertension is directed at the underlying cause, exacerbating factors, and the magnitude of the blood pressure abnormality. Healthy behavioral changes are a primary management tool for treating hypertension and, more particularly, prehypertension and for addressing other cardiovascular risk factors, such as obesity. Pharmacological management is reserved for patients with hypertension who do not respond to behavioral changes, have additional cardiovascular risk factors or diabetes, are symptomatic, or have developed target-organ damage.

Serum adiponectin levels and ambulatory blood pressure monitoring in pediatric renal transplant recipients

BACKGROUND.: Reduced levels of serum adiponectin, an adipokine, are associated with cardiovascular and obesity-related diseases; however, relations between adiponectin and hypertension are unclear. METHODS.: This cross-sectional study examined adiponectin and ambulatory blood pressure monitoring (ABPM) in 33 pediatric renal transplant recipients (TXP), aged 8 to 19 years, median of 1.9 years after transplant. Serum total adiponectin (microg/mL) and high molecular weight-to-total adiponectin ratio (HMWr), 24-hr ABPM, and dual x-ray absorptiometry measures of fat mass were obtained. RESULTS.: The 12 TXP with hypertension (defined as BP index >1.0 and BP load >25%) had lower total adiponectin levels (7.4+/-3.2 vs. 10.9+/-5.2 microg/mL, P=0.045) compared with nonhypertensive TXP. Hypertensive TXP trended toward lower HMWr compared with nonhypertensive TXP (0.40+/-0.09 vs. 0.47+/-0.11, P=0.064). Levels did not differ according to sex, obesity or dipper status. In univariate analyses, total adiponectin and HMWr were negatively and significantly correlated with indexed BP in the daytime, nighttime, and 24-hr periods (R=-0.35 to -0.57). After adjustment for estimated glomerular filtration rate, fat mass, anti-hypertensive medication and fasting glucose, (1) lower total adiponectin was significantly and independently associated with greater elevations in all ABPM indexes except for nighttime systolic indexed BP, and (2) HMWr was inversely associated with all ABPM indexes. Lower adiponectin levels (P=0.049) and HMWr (P=0.042) were associated with greater odds of hypertension. CONCLUSION.: These data indicate that lower total adiponectin and HMWr were significantly and independently associated with greater ambulatory blood pressure.

Regression of target organ damage in children and adolescents with primary hypertension

We assessed the effects of 12 months of non-pharmacological and pharmacological therapy on 24-h ambulatory blood pressure, regression of target organ damage (TOD) and metabolic abnormalities in 86 children (14.1 ± 2.4 years) with primary hypertension. Twenty-four hour systolic and diastolic blood pressure (BP) decreased (130 ± 8 vs 126 ± 8, 73 ± 7 vs 70 ± 7, p = 0.0001 and 0.004 respectively). Body mass index (BMI) did not change, but waist-to-hip (0.85 ± 0.07 vs 0.83 ± 0.05, p = 0.01) and waist-to-height ratio (WHtR; 0.49 ± 0.07 vs 0.48 ± 0.05, p = 0.008) decreased. Left ventricular mass index (LVMi; 38.5 ± 10.7 vs 35.2 ± 7.5 g/m(2.7), p = 0.0001), prevalence of left ventricular hypertrophy (46.5% vs 31.4%; p = 0.0001), carotid intima-media thickness (cIMT; 0.44 ± 0.05 vs 0.42 ± 0.04 mm, p = 0.0001), wall cross sectional area (WCSA; 7.5 ± 1.3 vs 6.9 ± 1.2 mm(2), p = 0.002), hsCRP (1.1 ± 1.0 vs 0.7 ± 0.7 mg/l, p = 0.002), and LDL-cholesterol (115 ± 33 vs 107 ± 26 mg/dl, p = 0.001) decreased. Patients who had lowered BP had a lower cIMT at the second examination (0.41 ± 0.04 vs 0.43 ± 0.04 mm, p = 0.04) and lower initial hsCRP values (0.9 ± 0.7 vs 1.5 ± 1.3 mg/l, p = 0.04) in comparison to non-responders. Regression analysis revealed that the main predictor of LVMi decrease was a decrease in abdominal fat expressed as a decrease in waist circumference (WC) (R (2) = 0.280, β = 0.558, p = 0.005), for WCSA-SDS a decrease in WC (R (2) = 0.332, β = 0.611, p = 0.009) and for a cIMT-SDS decrease the main predictor was a decrease in hsCRP concentrations (R (2) = 0.137, β = 0.412, p = 0.03). Standard antihypertensive treatment lowered BP and led to regression of TOD in hypertensive children. Lean body mass increase and decrease in abdominal obesity correlated with TOD regression.

Left ventricular geometry in children and adolescents with primary hypertension

BACKGROUND

Children with hypertension (HTN) are at increased risk for left ventricular hypertrophy (LVH). Increased left ventricular (LV) mass (LVM) by the process of remodeling in response to volume or pressure loading may be eccentric (increased LV diameter) or concentric (increased wall thickness). Our objective was to classify LV geometry among children with primary HTN and examine differences in ambulatory blood pressure (ABP).

METHODS

Subjects aged 7-18 years with suspected HTN were enrolled in this cross-sectional study. ABP and LVM index (LVMI) were measured within the same 24-h period. LV geometry was classified as normal, concentric remodeling, concentric LVH, or eccentric LVH.

RESULTS

Children with LVH had significantly higher ambulatory systolic BP (SBP) and diastolic blood pressure (BP) (DBP) levels and body mass index (BMI) Z-score. Sixty-eight children had HTN based upon ABP monitoring (ABPM). Thirty-eight percent of the hypertensive subjects had LVH, with equal distribution in the concentric and eccentric groups. There were significant differences in the 24-h DBP parameters when the eccentric LVH group was compared to the normal geometry and concentric LVH groups. Relative wall thickness (RWT) was inversely associated with night time DBP parameters. These relationships persisted after controlling for BMI Z-score.

CONCLUSIONS

Although the risk for LVH is associated with increased SBP and BMI Z-score, those with eccentric LVH had significantly higher DBP.

Left ventricular geometry in children and adolescents with primary hypertension

BACKGROUND

Children with hypertension (HTN) are at increased risk for left ventricular hypertrophy (LVH). Increased left ventricular (LV) mass (LVM) by the process of remodeling in response to volume or pressure loading may be eccentric (increased LV diameter) or concentric (increased wall thickness). Our objective was to classify LV geometry among children with primary HTN and examine differences in ambulatory blood pressure (ABP).

METHODS

Subjects aged 7-18 years with suspected HTN were enrolled in this cross-sectional study. ABP and LVM index (LVMI) were measured within the same 24-h period. LV geometry was classified as normal, concentric remodeling, concentric LVH, or eccentric LVH.

RESULTS

Children with LVH had significantly higher ambulatory systolic BP (SBP) and diastolic blood pressure (BP) (DBP) levels and body mass index (BMI) Z-score. Sixty-eight children had HTN based upon ABP monitoring (ABPM). Thirty-eight percent of the hypertensive subjects had LVH, with equal distribution in the concentric and eccentric groups. There were significant differences in the 24-h DBP parameters when the eccentric LVH group was compared to the normal geometry and concentric LVH groups. Relative wall thickness (RWT) was inversely associated with night time DBP parameters. These relationships persisted after controlling for BMI Z-score.

CONCLUSIONS

Although the risk for LVH is associated with increased SBP and BMI Z-score, those with eccentric LVH had significantly higher DBP.

Masked hypertension associates with left ventricular hypertrophy in children with CKD

Left ventricular hypertrophy (LVH) associates with increased risk for cardiovascular disease. Hypertension leads to LVH in adults, but its role in the pathogenesis of LVH in children is not as well established. To examine left ventricular mass and evaluate factors associated with LVH in children with stages 2 through 4 chronic kidney disease (CKD), we analyzed cross-sectional data from children who had baseline echocardiography (n = 366) and underwent ambulatory BP monitoring (n = 226) as a part of the observational Chronic Kidney Disease in Children (CKiD) cohort study. At baseline, 17% of children had LVH (11% eccentric and 6% concentric) and 9% had concentric remodeling of the left ventricle. On the basis of a combination of ambulatory and casual BP assessment (n = 198), 38% of children had masked hypertension (normal casual but elevated ambulatory BP) and 18% had confirmed hypertension (both elevated casual and ambulatory BP). There was no significant association between LVH and kidney function. LVH was more common in children with either confirmed (34%) or masked (20%) hypertension compared with children with normal casual and ambulatory BP (8%). In multivariable analysis, masked (odds ratio 4.1) and confirmed (odds ratio 4.3) hypertension were the strongest independent predictors of LVH. In conclusion, casual BP measurements alone are insufficient to predict the presence of LVH in children with CKD. The high prevalence of masked hypertension and its association with LVH supports early echocardiography and ambulatory BP monitoring to evaluate cardiovascular risk in children with CKD.

Poor glycemic control is associated with abnormal changes in 24-hour ambulatory blood pressure in children and adolescents with type 1 diabetes mellitus

INTRODUCTION

Twenty-four hour ambulatory blood pressure (ABPM) is emerging as a valuable tool to assess blood pressure (BP) changes in children with type 1 diabetes mellitus (DM1). Hypertension (HTN) is an important risk factor for, and may be an important indicator of diabetic nephropathy. Early accurate identification of HTN in DM1 may improve outcomes.

AIM

To evaluate BP in adolescents with DM1 using 24-hour ABPM, and to identify risk factors associated with abnormal blood pressure.

METHOD

The ABPM of 105 children with DM1 was reviewed. Mean systolic BP (sBP) percentile was determined from the National High Blood Pressure Education Program (NHBPEP) tables. The patients with abnormal sBP were compared to those with normal sBP with respect to age, race, sex, body mass index (BMI) percentile, duration of DM1, average hemoglobin A1c (HbA1c) over the preceding year, and family history of hypertension.

RESULTS

Mean sBP was normal in 71%, whereas 23% had pre-hypertension, and 6% had stage 1 hypertension. Those who had abnormal sBP (pre-hypertension and stage 1 hypertension) had higher HbA1c (p = 0.023) and were more likely to be male (p = 0.03) than those with normal sBP.

CONCLUSION

Stage 1 hypertension is present in 6%, and pre-hypertension in 23% of adolescents with DM1. Poor diabetes control and male gender appear to be risk factors for abnormal sBP as measured by 24-hour ambulatory blood pressure monitoring.

Arterial HTN in children with T1DM--frequent and not easy to diagnose

INTRODUCTION

To evaluate the diagnostic efficacy of the office blood pressure (OBP) and ambulatory blood pressure monitoring (ABPM) in the assessment of hypertension (HTN) in children with diabetes mellitus type 1 (T1DM).

METHODS

We analyzed OBP and ABPM measurements in 84 diabetic children (43 boys) obtained at a median age of 14.9 yr and 6.3 +/- 3.5 yr after diagnosis of T1DM. OBP and ABPM results were converted into standard deviation scores (SDS). In addition, we analyzed blood pressure loads and nighttime dipping. The comparison between OBP and ABPM was performed using kappa coefficient and receiver operator curve (ROC).

RESULTS

HTN was diagnosed in 43/84 (51%) patients using OBP (>95th percentile), and in 24/84 (29%) patients using ABPM ( > or = 95th percentile during 24 h, day or night). Both methods were in agreement in 33 ABPM normotensive and 16 ABPM hypertensive patients (most had nighttime HTN); 32% patients had white-coat HTN and 9.5% patients had masked HTN. The kappa coefficient was 0.175 (95% CI from -0.034 to 0.384) suggesting poor agreement between OBP and ABPM. Diastolic OBP was a better predictor of ABPM HTN (ROC area under the curve (AUC) = 0.71 +/- 0.06) than systolic OBP (AUC = 0.58 +/- 0.07). The percentage of non-dippers ranged from 7 to 23% in ABPM normotensive patients, and 21-42% in ABPM hypertensive patients who also had significantly higher BP loads (p < 0.0001).

CONCLUSION

Children with T1DM often suffer from nocturnal, white coat- and masked HTN, which can not be assessed and predicted by the OBP.