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

Effect of plasma NOx values on cardiac function in obese hypertensive and normotensive pediatric patients

BACKGROUND

Hypertension (HT) is a major comorbidity of obesity that is associated with an increased risk of cardiovascular disease and higher mortality. The aim of our study was to evaluate cardiac function in obese hypertensive (OHT) and obese normotensive (ONT) pediatric patients and determine the effects of plasma nitric oxide (NOx) values on cardiac function, while demonstrating the role of plasma NOx in HT in obese pediatric patients.

METHODS

The study population consisted of 62 patients (27 boys, 35 girls), aged 13-18 years and 21 age-matched healthy controls. All subjects enrolled in the study underwent echocardiography (Echo) evaluation and ambulatory blood pressure monitoring for HT. Plasma NOx and biochemical values were studied in both patient groups separately.

RESULTS

Plasma NOx levels were found to be lower in the OHT group than in the ONT and control groups (p < 0.001) and to be negatively correlated with left ventricular mass index values (p < 0.05). Both the OHT and ONT groups had concentric hypertrophy of the heart.

CONCLUSIONS

Plasma NOx plays an essential role in obesity-induced HT. Concentric hypertrophy of the left ventricle was found in both the OHT and ONT groups, indicating structural deformation of the heart.

Impact of Different Initial Epinephrine Treatment Time Points on the Early Postresuscitative Hemodynamic Status of Children With Traumatic Out-of-hospital Cardiac Arrest

The postresuscitative hemodynamic status of children with traumatic out-of-hospital cardiac arrest (OHCA) might be impacted by the early administration of epinephrine, but this topic has not been well addressed. The aim of this study was to analyze the early postresuscitative hemodynamics, survival, and neurologic outcome according to different time points of first epinephrine treatment among children with traumatic OHCA.Information on 388 children who presented to the emergency departments of 3 medical centers and who were treated with epinephrine for traumatic OHCA during the study period (2003-2012) was retrospectively collected. The early postresuscitative hemodynamic features (cardiac functions, end-organ perfusion, and consciousness), survival, and neurologic outcome according to different time points of first epinephrine treatment (early: <15, intermediate: 15-30, and late: >30 minutes after collapse) were analyzed.Among 165 children who achieved sustained return of spontaneous circulation, 38 children (9.8%) survived to discharge and 12 children (3.1%) had good neurologic outcomes. Early epinephrine increased the postresuscitative heart rate and blood pressure in the first 30 minutes, but ultimately impaired end-organ perfusion (decreased urine output and initial creatinine clearance) (all P < 0.05). Early epinephrine treatment increased the chance of achieving sustained return of spontaneous circulation, but did not increase the rates of survival and good neurologic outcome.Early epinephrine temporarily increased heart rate and blood pressure in the first 30 minutes of the postresuscitative period, but impaired end-organ perfusion. Most importantly, the rates of survival and good neurologic outcome were not significantly increased by early epinephrine administration.

Myocardial Performance Index in Childhood Onset Essential Hypertension and White Coat Hypertension

BACKGROUND

As a global measure of ventricular systolic and diastolic function, the myocardial performance index (MPI) can be an early indicator of hypertensive cardiomyopathy in children with essential hypertension (EH).

METHODS

Children with untreated newly diagnosed EH and white coat hypertension (WCH) by a 24-hour ambulatory blood pressure monitoring (ABPM), both groups without any identifiable etiology for the hypertension, were enrolled for the study. Echocardiograms and vascular ultrasounds for carotid artery intimal medial thickness were performed on all children prior to therapy. Diastolic function (peak E and A velocities, E/A ratio, isovolumic relaxation time, and deceleration times) and MPI were evaluated by simultaneous transmitral and transaortic spectral Doppler flow velocities. Systolic function was evaluated by shortening fraction and ejection fraction.

RESULTS

A cohort of 66 children (24 with EH, 42 with WCH, males 61%, median age of 13 years, range 10-17 years) were enrolled in the study. The demographic, anthropometric, laboratory tests, vascular ultrasound, and conventional echocardiographic parameters were similar between the 2 groups. There was a very small difference in MPI between the EH and WCH children (0.28 SD: 0.07 vs. 0.31 SD: 0.08, P = 0.045). However, in EH children, MPI increased by 0.14 units for every 10 unit increase in mean ABPM systolic BP (95% confidence interval: 0.03-0.25).

CONCLUSIONS

We found the increasing MPI was associated with increasing 24-hour mean systolic BP in children with EH. Therefore, MPI may have utility as a single, quick, noninvasive method of detection and tracking of subclinical hypertensive heart disease.

Association of Nocturnal Hypertension With Disease Activity in Rheumatoid Arthritis

OBJECTIVES

Both nocturnal hypertension (HT) and systemic inflammation underlying rheumatoid arthritis (RA) have been shown to be independent predictors of cardiovascular disease (CVD), although little is known on the relationship between nocturnal blood pressure (BP) and disease activity in RA patients.

METHODS

We performed 24-hour ambulatory BP monitoring (ABPM) in 71 RA patients to examine the relationship of nocturnal fall in BP and RA disease activity based on a disease activity score of 28 joint counts with C-reactive protein (CRP, 28-joint disease activity score (DAS28)-CRP). Among them, 25 RA patients whose consent obtained were reexamined by ABPM to assess the improvement of nocturnal fall in BP after RA therapeutic intervention.

RESULTS

The mean DAS28-CRP level was 4.8±1.6 in 71 RA patients. The mean nocturnal fall in BP was 5.6±8.9%. DAS28-CRP was associated significantly and independently in a negative manner with the nocturnal fall in BP (β = -0.388, P = 0.004). In 25 RA patients, DAS28-CRP improved from 5.4±1.1 to 3.5±0.8 (P < 0.0001) and the nocturnal fall in BP increased significantly from 4.5±9.2% to 10.6±5.8% (P = 0.002) with the significant decrease of nighttime systolic BP (SBP) from 121.2±22.5mm Hg to 112.5±18.8mm Hg (P = 0.02) in spite of no change in daytime BP after 4 weeks of RA treatment.

CONCLUSIONS

The present study observed that higher RA activity was associated with lower nocturnal fall in BP, but not daytime BP, in RA patients.

Can ambulatory blood pressure monitoring detect early diastolic dysfunction in children with type 1 diabetes mellitus: correlations with B-type natriuretic peptide and tissue Doppler findings

AIM

To evaluate the relationship between 24-h blood pressure (BP) measurements and diastolic heart function evaluated by Doppler tissue imaging and B-type natriuretic peptide (BNP) levels in children with type 1 diabetes mellitus (DM).

PATIENTS AND METHODS

A total of 32 diabetic and 18 healthy children were enrolled. Spectral Doppler analysis and tissue Doppler measurements were performed by conventional echocardiography. The 24-h ambulatory BP and serum BNP levels were measured.

RESULTS

Analysis of ambulatory blood pressure monitoring (ABPM) recordings showed that median daytime diastolic BP load were significantly higher in diabetic patients compared to controls [12.35 (4.23-27.23) vs. 2.5 (0-8.7), p = 0.007]. Patients with elevated daytime systolic and diastolic BP loads had significantly higher BNP values compared to patients with normal BP load (31.4 ± 24.36 vs. 11.84 ± 11.25 pg/mL, p = 0.03 and 23.21 ± 15.12 vs. 12.12 ± 14.65 pg/mL, p = 0.03, respectively). Isovolemic contraction time (47.43 ± 7.84 vs. 42.27 ± 7.47, p = 0.045), isovolemic relaxation time (68.84 ± 10.43 vs. 58.77 ± 10.02, p = 0.02), and myocardial performance index (0.45 ± 0.10 vs. 0.37 ± 0.09, p = 0.02) as determined by tissue Doppler echocardiography were significantly high in diabetic patients compared to that of control cases. Ratio of mitral peak early diastolic flow velocity (E) to peak early diastolic myocardial velocities by tissue Doppler echocardiography (E') was also higher in patients with elevated daytime systolic BP load (E/E', 6.71 ± 1.97 vs. 4.91 ± 1.02, p = 0.04).

CONCLUSION

Elevated BP loads detected by 24-h ambulatory BP measurements in children with type 1 diabetes are associated with increased BNP levels and abnormal tissue Doppler echocardiography indices, indicating early stage cardiac dysfunction.

Association of myeloperoxidase levels with cardiometabolic factors and renal function in prepubertal children

INTRODUCTION

Myeloperoxidase (MPO), an enzyme linking obesity and cardiovascular (CV) risk in adults, has rarely been studied in young children and no studies assessed its association with renal function. We sought to explore a possible association between serum MPO levels, obesity, CV risk factors and renal function in prepubertal children.

MATERIALS/METHODS

Cross-sectional evaluation of 309 children aged 8-9 years (161 normal weight, 148 overweight/obese), members of the birth cohort Generation I (Portugal). Anthropometrics (body mass index (BMI), waist-to-height ratio (WHtR) and % body fat mass (%BFM) by bioelectrical impedance analysis), 24-h ambulatory blood pressure monitoring and pulse wave velocity (PWV) were measured. Insulin resistance was estimated by the HOMA index (considering serum fasting glucose and insulin determinations). Serum MPO levels were assessed by immunoenzymatic assay.

RESULTS

MPO levels were positively associated with obesity indices (BMI z-score, WHtR and %BFM). Higher MPO levels were associated with higher 24-h and night-time mean arterial pressure, with nondipping and with higher values of insulin resistance. In normal weight children, the endothelial function, as evaluated indirectly by PWV, was an independent predictor of MPO levels. In overweight/obese children, estimated glomerular filtration rate increased significantly across tertiles of MPO (Ptrend = 0·031) and this association held after adjustment for age, sex, neutrophil and monocyte counts and CV risk factors.

CONCLUSIONS

Our results reinforce the role of MPO as a risk marker in obesity and related CV morbidities in young children. MPO levels associate with the dipping pattern and PWV and, among overweight/obese children, an association exists between MPO and renal function.

Nocturnal Hypertension and Attenuated Nocturnal Blood Pressure Dipping is Common in Pediatric Lupus

Hypertension is an important manifestation of systemic lupus erythematosus (SLE) but reports of prevalence vary between 20-70% in published reports of adult and pediatric patients. For both children and adults with SLE, the clinical diagnosis and management of hypertension has traditionally been based on guidelines developed for the general population. In clinical trials, the criteria used for defining participants with hypertension are mostly undefined. As a first step towards formally assessing the blood pressure (BP) patterns of children diagnosed with SLE, 24-hr ambulatory BP monitoring data was analyzed on clinic patients who presented with prehypertension or stage I hypertension. In this pediatric SLE cohort (n=10), 20% met daytime criteria for a diagnosis of hypertension. Patterns of BP elevation varied widely with white coat, masked, isolated systolic, and diastolic nocturnal hypertension all identified. Nocturnal hypertension was detected in 60% and attenuated nocturnal BP dipping in 90% of both hypertensive and normotensive SLE patients. In SLE patients, the median nighttime systolic and diastolic loads were 25% and 15.5% compared with median daily loads of 12.5% and 11.5%. Daytime and nighttime systolic and diastolic BP load and nocturnal dipping was compared to a control population consisting of 85 non-SLE patients under 21 years old with prehypertension or stage 1 hypertension presenting to hypertension clinic. Median systolic BP dipped 5.3 mmHg in SLE patients compared to 11.9 mmHg in non-lupus ( p-value = 0.001). Median diastolic BP dipped 12.9 mmHg versus 18.5 mmHg in non-lupus ( p-value = 0.003). Patterns of BP dysregulation in pediatric SLE merit further exploration. Children with or without SLE displaying prehypertensive or stage 1 casual BP measurements had similar rates of hypertension by ambulatory BP monitoring. However, regardless of BP diagnosis, and independent of kidney involvement, there was an increased proportion with attenuated nocturnal dipping and nocturnal hypertension in SLE patients.

Role of 24-h ambulatory blood pressure monitoring in children with chronic kidney disease

Hypertension is common in children with chronic kidney disease (CKD) and is a major determinant of CKD progression. Ambulatory blood pressure monitoring (ABPM) has been proposed to be better in detecting hypertension as compared to casual blood pressure (CBP). This study aims to study the usefulness of ABPM in detecting masked hypertension, evaluating the adequacy of blood pressure (BP) control and predicting left ventricular hypertrophy (LVH) amongst children with CKD. A prospective cross-sectional study of 46 children with stage 3–5 CKD was conducted at the Pediatric Nephrology department of a tertiary hospital in South India. All children underwent CBP, ABPM and an echocardiography. Results were categorized as normal BP; confirmed hypertension; masked hypertension and white coat hypertension. Out of 46 children studied, 11 were undergoing dialysis. While 39.1% children had stage 3 and 4 CKD each, 21.7% had stage 5 CKD. Masked hypertension was detected in 19.6% and 21.7% had confirmed hypertension. Thirty-four (73.9%) children were already receiving antihypertensive medication. In these, CBP was elevated in 23.5% and ABP in 47%. Among children with hypertension as defined by ABPM, LVH was detected in 32.2%. We found that higher the number of abnormal ABPM indices (assessed by BP Index, nocturnal dipping and BP Load) higher the likelihood of LVH (P = 0.046). ABPM is better in detecting hypertension and monitoring adequacy of treatment 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 risks in this population.

Hypertension in children after renal transplantation

BACKGROUND

Hypertension (HT) is a common and serious complication following renal transplantation in children, and an important risk factor for cardiovascular morbidity and mortality. This study evaluated the clinical characteristics of HT in children after renal transplantation.

METHODS

Twenty-four children who were followed up at least 6 months after renal transplantation were enrolled in the study. From the clinical records, demographic and laboratory data, casual blood pressure (BP) measurement, ambulatory BP monitoring (ABPM), medication, and left ventricular mass index (LVMI) at echocardiogram were documented.

RESULTS

Mean age at time of transplantation was 12.6 ± 3.0 years and mean follow-up period was 19.6 ± 15.8 months. HT was detected in 21 children (87.5%) after renal transplantation. Twelve patients (50%) had HT both before and after transplantation and nine (38%) had HT only after transplantation. HT developed in 67% within the first week and in 95% within the first month. All hypertensive children had night-time HT and no child had isolated daytime HT. The efficacy of HT control was 42%. Median LVMI in patients with HT after renal transplantation was 42.3 g/m(2.7).

CONCLUSIONS

Severe HT, an important complication, was frequently seen in the early period after renal transplantation. Predominance of nocturnal HT and the lack of isolated daytime HT after transplantation underline the importance of ABPM. ABPM should be performed regularly in the first year after transplantation, not only for diagnosis but also for evaluation of HT control.

Elevated uric acid and obesity-related cardiovascular disease risk factors among hypertensive youth

BACKGROUND

Uric acid (UA) is associated with high blood pressure in adolescents and with left ventricular hypertrophy (LVH) and cardiovascular disease (CVD) in adults. We sought to determine if UA is independently associated with CVD risk factors and left ventricular mass (LVM) over time in hypertensive youth.

METHODS

This was a 1-year prospective observational study of hypertensive children aged 3-19 years. Cross-sectional and longitudinal associations of serum UA with CVD risk factors and LVM were explored.

RESULTS

Of the 49 children who completed both the baseline and 12-month assessments, at baseline the mean age was 13.8 years and mean UA was 5.5 mg/dL; 24% had elevated UA, 51% were overweight/obese and 39% had LVH. Measures of adiposity, low high-density lipoprotein cholesterol, high-sensitivity C-reactive protein, LVM and LVH were all significantly associated with elevated UA at baseline, but not with change over time. Each 1 mg/dL increase in baseline UA was associated with a 2.5 g/m(2.7) increase in the LVM index at follow-up (95% confidence interval 0.64, 4.39; p = 0.01); after adjustment for age, sex, race, body mass index z-score, change in UA, time, blood pressure and medication use, this association was no longer significant.

CONCLUSIONS

Hypertensive children with elevated UA have a higher prevalence of obesity-related CVD risk factors. Among hypertensive children, UA may be a marker of adiposity and not an independent CVD risk factor.

Obstructive sleep apnea and periodic limb movement disorder in a population of children with hypertension and/or nocturnal nondipping blood pressures

There is a reported association between hypertension (HTN) and sleep disorders. The American Academy of Pediatrics recommends screening children with HTN for sleep disorders because sleep disorders increase the risk for cardiovascular disease. We quantified the frequency and severity of sleep disorders within our institution's hypertensive pediatric population and evaluated the effectiveness of performing nocturnal polysomnography (NPSG). In the hypertensive pediatric population referred for NPSG at our institution, 64% were diagnosed with obstructive sleep apnea (OSA) and/or periodic limb movement disorder. Thirty-three percent of those children with HTN had moderate to severe OSA, whereas only 20% of all children evaluated by NPSG had moderate to severe OSA. Those children with HTN were also two times more likely to be diagnosed with periodic limb movement disorder. Screening for sleep disorders and obtaining NPSG in children with HTN increase the identification of comorbid sleep disorders and reduce the risk for cardiovascular disease.

Relationship of ambulatory blood pressure and body mass index to left ventricular mass index in pediatric patients with casual hypertension

Both obesity and hypertension are associated with left ventricular hypertrophy (LVH) in children. Our objective was to compare the prevalence of LVH in obese and nonobese subjects with casual hypertension who underwent ambulatory blood pressure monitoring (ABPM). Untreated children (aged 6-20 years) underwent 24-hour ABPM, and left ventricular mass index (LVMI) was measured. Subjects were classified into three groups: white coat hypertension (WCH), prehypertension (pre-HT), and hypertension (HT). The prevalence of LVH was compared between obese and nonobese subjects among the groups. Of 69 children who underwent ABPM, thirty-two patients (46%) had WCH, 13 (19%) had pre-HT, and 24 (35%) had HT. Mean age, BMI, and LVMI were similar in the groups (P = not significant [NS]). In all, 22 patients (32%) had LVH, with no difference among WCH versus pre-HT versus HT (37.5% vs. 46% vs. 16.7%, P = NS). Twenty-seven subjects (39%) were obese. The ratio of LVH in obese to nonobese was 55.5% to 16.6% (P = .001). In both pre-HT and WCH, patients with LVH had a significantly higher BMI z score (P = .02 and P = .01, respectively). LVMI correlated strongly with BMI z score (P = .0001) but not with any blood pressure parameter. Almost half of children with casual HT have WCH. LVH is prevalent in a third of children with HT, pre-HT, and WCH. In both pre-HT and WCH, patients with LVH were more likely to be obese. More than half of all the obese subjects had LVH. Obese children in all three groups may be at a greater risk for end organ damage.

Differences between office and ambulatory blood pressures in children and adolescents attending a hospital hypertension clinic

BACKGROUND AND OBJECTIVES

Information on ambulatory blood pressure monitoring (ABPM) in children is scarce. While in adults office BP (OBP) is higher than ABP and the difference increases as OBP increases, information in children suggests that at this young age ABP is no lower and often higher than OBP. This study was aimed at describing OBP-ABP differences in a cohort of children of different ages and BPs, and investigating whether OBP-ABP differences are dependent on age or OBP level.

METHODS

We retrospectively compared OBP and 24-h, daytime and night-time ABP in 433 children and adolescents aged 4-18 years, referred to our hospital clinic.

RESULTS

OBP was found to be significantly lower than 24-h and daytime ABP in the low age tertile (4-10 years) but not in the medium and high tertiles. OBP was also lower than ABP in normotensive patients (n = 182), but higher than ABP in untreated hypertensive patients (n = 92) despite similar ages. Continuous analyses showed a weak correlation of OBP-ABP differences with age, and a much stronger correlation with OBP so that 24-h ABP was higher than OBP at OBP values less than 117/73 mmHg and lower than OBP at higher OBP values. Logistic regression analysis indicates that also in children OBP accounts for most of the OBP-ABP difference.

CONCLUSION

There is a common relation both in children and adults between OBP and ABP. It is only because high OBP is common in the elderly, and the lowest OBP is usually found in young children that large positive OBP-ABP differences have been associated with old age, and negative differences with childhood. OBP-ABP differences, often defined as white-coat effect, can have different directions and are likely to be largely due to regression to the mean.

Prenatal Cocaine Exposure and Cardiometabolic Disease Risk Factors in 18- to 20-Year-Old African Americans

OBJECTIVE

The long-term effects of prenatal cocaine exposure (PCE) on physical health are largely unknown. No human studies support or refute a relationship between PCE and the long-term risk for cardiovascular and/or metabolic disease. We investigated the association of PCE on primary cardiometabolic disease risk factors in African Americans (AA) aged 18 to 20 years.

DESIGN

Cohort, longitudinal, prospective.

SETTING

Miami-Dade County, Florida, and the University of Miami Miller School of Medicine/Jackson Memorial Medical Center.

PARTICIPANTS

Healthy full-term inner-city AA adolescents (aged 18 to 20 years, n=350) previously enrolled at birth from 1990-1993.

MAIN OUTCOME MEASURES

Fasting serum insulin, glucose, lipids, and high-sensitivity C-reactive protein; systolic and diastolic blood pressures; and the components and prevalence of the metabolic syndrome.

RESULTS

There were no PCE-associated differences in cardiometabolic disease risk factors including the metabolic syndrome and its individual components in AAs aged 18 to 20 years.

CONCLUSIONS

The results of our study do not support an association between PCE and increased cardiometabolic disease risk in AAs aged 18 to 20 years. Whether PCE is associated with cardiovascular or metabolic disease in adulthood would require further investigation.

Association Between Adiposity and Left Ventricular Mass in Children With Hypertension

Left ventricular hypertrophy (LVH) is prevalent among hypertensive children; however, blood pressure (BP) does not predict its presence. The authors conducted a 1-year prospective cohort study to examine the hypothesis that obesity-related risk factors are associated with left ventricular mass index (LVMI) in hypertensive children, and the association between adiposity and LVMI is mediated by BP-dependent and -independent pathways. A total of 49 hypertensive children were enrolled: 51% were overweight/obese and 41% had LVH at baseline. Children overweight/obese at baseline and follow-up had a greater LVMI increase than those of healthy weight at each visit: mean change of 6.4 g/m(2.7) vs 0.95 g/m(2.7) . Baseline body mass index z score was independently associated with LVMI change (β=4.08, 1.54-6.61; P=.002). Only pulse pressure and serum aldosterone partially mediated this relationship. Hypertensive youth manifest multiple cardiovascular disease risk factors that worsen over time despite treatment. Of these, adiposity is most associated with LVH and increasing LVMI.

Masked hypertension in extremely preterm adolescents

AIM

Extremely preterm (EPT, born <28 weeks gestation) or extremely low birthweight (ELBW, birthweight <1000 g) individuals are at increased risk of high blood pressure (BP) and cardiovascular disease. We compared office BP measurements with 24-h ambulatory BP measurement (ABP) in EPT/ELBW individuals at age 18 years and term controls, and determined the sensitivity and specificity of office BP in predicting masked hypertension (24-h ABP measurements > 130/80).

METHODS

All EPT/ELBW individuals and matched term control adolescents born in Victoria, Australia, between 1991 and 1992 were recruited. A subset of this cohort was seen at 18 years, and researchers blinded to birth status measured office BP and ABP. We established the office BP thresholds that had the highest sensitivity and specificity in predicting masked hypertension.

RESULTS

EPT/ELBW (N = 120) individuals had higher mean BP measurements at 18 years, compared with controls (N = 71). Although there were no significant differences in rates of high BP between groups, high proportions of both EPT/ELBW (43.3%) and term control (36.6%) participants met criteria for masked systolic hypertension. In EPT/ELBW individuals, office systolic BP measurement of ≥122.5 mmHg predicted masked systolic hypertension (sensitivity 79%, specificity 74%). Office diastolic BP measurement of ≥75.5 mmHg predicted masked diastolic hypertension (sensitivity 77%, specificity, 77%).

CONCLUSIONS

At age 18 years, EPT/ELBW individuals have higher systolic and diastolic BP, compared with controls. Office BP may be an adequate screen for masked hypertension in EPT/ELBW survivors, but further research is needed to identify accurate ABP thresholds for masked hypertension for young Australians.

Blood Pressure Monitoring During the Induction and Maintenance Period of Propranolol Therapy for Complicated Infantile Hemangiomas: A Prospective Study of 109 Infants

BACKGROUND

Propranolol has become the first-line treatment for complicated infantile hemangiomas (CIHs) worldwide. Recommendations for monitoring infants undergoing propranolol therapy vary. Data on long-term blood pressure (BP) monitoring have not been reported before.

OBJECTIVE

The objective of the current study was to monitor BP in full-term infants during the induction and maintenance phase of propranolol therapy.

METHODS

BP was monitored prospectively in 109 infants (mean age 2.8 mos, range 1-5 mos) with CIHs during the induction (3-4 days in the hospital during up-dosing from 0.5 to 2.0 mg/kg/day) and maintenance (6 mos) phases of oral propranolol therapy.

RESULTS

Four children were excluded from the study because of sinus bradycardia (n = 2 [1.8%]) or lethargy (n = 2 [1.8%]). Mean systolic BP (SBP) decreased by 5 mmHg with the increase in propranolol dosage. Low (<5th percentile) SBP or diastolic BP (DBP) was observed in 2 of 105 children (1.9%) each. During the maintenance phase, 2 of 105 children (1.9%) had occasional SBP readings of less than 70 mmHg. No hypotension was observed after the third month of therapy. Low DBP (<36 mmHg) was recorded in 16 (15.2%) children after the first month, in 8.6% after the second, and in 2.9% during the third and fourth months of therapy. No patients exhibited clinical hypotension, bradycardia, or other known side effects of propranolol. Clinical response to therapy was excellent.

LIMITATIONS

Reference BP values were derived from published tables, not from an untreated control group.

CONCLUSIONS

In healthy full-term infants, propranolol (2 mg/kg/day divided in three doses) is well tolerated. No clinically significant hypotension was observed. We conclude that for otherwise healthy infants, BP monitoring during long-term propranolol therapy for CIHs is not necessary.

Analysis of 24-Hour Ambulatory Blood Pressure Monitoring in Children With Obstructive Sleep Apnea: A Hospital-Based Study

In the present study, we aimed to verify associations between ambulatory blood pressure (ABP) and pediatric obstructive sleep apnea (OSA) in a hospital-based population. This was a cross-sectional observational study on children aged 4 to 16 years with OSA-related symptoms from a tertiary referral medical center. All children received overnight polysomnography and 24-hour recording of ABP. Severity of the disease was classified as primary snoring (apnea-hypopnea index, AHI <1), mild OSA (AHI 1-5), and moderate-to-severe OSA (AHI >5). For 195 children enrolled in this study (mean age, 7.8 ± 3.4 years; 69% boy), ABP increased as severity of OSA increased. During daytime, children with moderate-to-severe OSA had significantly higher systolic blood pressure (BP) (117.0 ± 12.7 vs 110.5 ± 9.3 mmHg), mean arterial pressure (MAP) (85.6 ± 8 .1 vs 81.6 ± 6.8 mmHg), and diastolic BP load (12.0 ± 9.6 vs 8.4 ± 10.9 mmHg) compared with children with primary snoring. During nighttime, children with moderate-to-severe OSA had significantly higher systolic BP (108.6 ± 15.0 vs 100.0 ± 9.4 mmHg), MAP (75.9 ± 9.6 vs 71.1 ± 7.0 mmHg), systolic BP load (44.0 ± 32.6 vs 26.8 ± 24.5 mmHg), systolic BP index (0.5 ± 13.1 vs -6.8 ± 8.5 mmHg), and higher prevalence of systolic hypertension (47.6% vs 14.7 %) compared with children with primary snoring. Multiple linear regression analyses revealed an independent association between AHI and nighttime systolic BP and MAP after adjusting for adiposity variables. This large hospital-based study showed that children with moderate-to-severe OSA had a higher ABP compared with children who were primary snorers. As elevated BP in childhood predicts future cardiovascular risks, children with severe OSA should be treated properly to prevent further adverse cardiovascular outcomes.

Evaluation of the relationship between serum adropin levels and blood pressure in obese children

BACKGROUND

The prevalence of obesity and related cardiovascular comorbodities is increasing rapidly. Adipokines play a major role in the pathogenesis of obesity-related inflammation and hypertension.

AIM

The aim of this study was to evaluate the serum adropin levels in obese children and to determine the relationship between adropin levels and blood pressure (BP) in the pediatric age group.

METHODS

Forty obese children (mean age: 12.5 ± 2.5 years; male/female ratio: 18/22) and 15 healthy controls (mean age: 15 ± 3.14 years; male/female ratio: 5/15) were included in the study. Serum adropin levels, and a number of laboratory and clinical variables were compared. Ambulatory blood pressure monitoring was performed on obese subjects. Relationship between adropin levels and BP variables was examined.

RESULTS

Serum adropin levels were significantly lower in obese subjects than in healthy controls (193.56 ± 94 vs. 289 ± 187 pg/mL, p = 0.03). Adropin levels were correlated negatively with body mass index z-score (r = -0.56; p = 0.034). There was no correlation between serum adropin levels and laboratory variables in obese subjects. Five of the patients (12.5%) were nondipper, and nine of the patients (22.5%) had hypertension. There was no significant correlation between serum adropin levels and BP variables.

CONCLUSION

Serum adropin levels were significantly lower in obese children; however, there was no correlation between serum adropin levels and BP variables. Further studies are needed to determine the role of adipokines on BP.

Using simplified blood pressure tables to avoid underdiagnosing childhood hypertension

BACKGROUND

Recent studies have revealed that hypertension remains underdiagnosed in a significant number of children despite their recorded office blood pressure (OBP) exceeding the recommended fourth report OBP thresholds. Simplified OBP thresholds have been proposed to reduce this underdiagnosis of hypertension in children. In clinical practice, OBP screened as elevated according to the fourth report OBP thresholds are referred for ambulatory blood pressure (ABP) monitoring to rule out 'white coat' hypertension.

OBJECTIVES

The present study tested the usefulness of simplified OBP thresholds to screen abnormal OBP for ABP monitoring referral.

METHODS

A total of 155 subjects were retrospectively analyzed with paired OBP and ABP recordings obtained from an outpatient referral clinic. OBP recordings were classified as abnormal according to the simplified and fourth report OBP thresholds. ABP measurements were classified as abnormal according to the ABP reference tables.

RESULTS

Simplified blood pressure (BP) tables correctly identified all OBP classified as abnormal according to fourth report BP thresholds (kappa [κ] 0.72 [95% CI 0.61 to 0.83]) for systolic OBP; κ 0.92 [95% CI 0.86 to 0.99] for diastolic OBP). OBP classified as abnormal by the simplified BP thresholds and by the fourth report BP thresholds performed similarly for correctly identifying abnormal ABP measurements as per ABP references (overlapping 95% CIs of the sensitivity, specificity and predictive values and likelihood ratios).

CONCLUSIONS

Simplified BP tables, proposed to reduce the underdiagnosis of hypertension in children, can serve as a useful screening tool to decide a referral for ABP monitoring. Future prospective studies are needed to establish these findings.

Nighttime Systolic Blood-Pressure Load Is Correlated with Target-Organ Damage Independent of Ambulatory Blood-Pressure Level in Patients with Non-Diabetic Chronic Kidney Disease

Background

The impacts of blood pressure (BP) load on target-organ damage in patients with chronic kidney disease (CKD) are largely unclear. We examined whether BP load is correlated with target-organ damage (TOD) in Chinese CKD patients independent of BP level.

Methods

We recruited 1219 CKD patients admitted to our hospital division in this cross-sectional study. The TOD were measured by estimated glomerular filtration rate (eGFR), proteinuria, left ventricular mass index (LVMI) and carotid intima-media thickness (cIMT) in this study. Univariate and multivariate linear analyses were used to evaluate the relationship between systolic blood pressure (SBP) load, diastolic blood pressure (DBP) load and these renal, cardiovascular parameters.

Results

In multivariable-adjusted models, BP load and ambulatory BP levels both independently correlated with LVMI, eGFR and proteinuria in all groups of CKD patients (p<0.05), 24-h SBP correlated with cIMT only in non-diabetic CKD patients without hypertension (p<0.05), while nighttime SBP load was associated with cIMT only in non-diabetic CKD patients (p<0.05). Furthermore, nighttime SBP load additionally increased coefficient of determination (R²) and correlated with LVMI, proteinuria in non-diabetic CKD patients without hypertension (R² = 0.034, P<0.001 and R² = 0.012, P = 0.006 respectively) and LVMI, cIMT, eGFR in non-diabetic CKD patients with hypertension (R²>0.008, P<0.05) in multivariable-adjusted model which already including the 24-h BP. BP load did not refine this correlation based on the 24-h BP level in diabetic CKD patients.

Conclusion

Night-time SBP load was correlated with TOD in patients with non-diabetic chronic kidney disease independent of BP level.

Hypertension in Young People: Epidemiology, Diagnostic Assessment and Therapeutic Approach

High blood pressure (BP) still remains one of the most relevant cardiovascular risk factors, also due to its persistently high prevalence and growing incidence in the general adult and elderly population. Since almost all hypertension-related cardiovascular complications, mostly including coronary artery disease, myocardial infarction, ischemic stroke, and congestive heart failure, occurred in adult and elderly individuals, evidence on both prevalence and clinical management of hypertension in young individuals are lacking. Therefore, the clinical impact of high BP levels in young populations remains to be explored. In the recent years, the attitude of the scientific community has changed and more attention was devoted to young individuals with hypertension, also in view of the fact that early identification of these subjects may prevent developing of established hypertension in adulthood. In addition, unhealthy lifestyle habits have progressively involved children and adolescents worldwide, thus contributing to further increase the risk of developing hypertension in young individuals. On the basis of these considerations, the present review is aimed at providing a brief reappraisal of the major aspects of hypertension in the young age, as well as at promoting interest and discussion on this important issue.

Hypertension Prevalence, Cardiac Complications, and Antihypertensive Medication Use in Children

OBJECTIVE

To determine the prevalence of hypertension diagnosis in children of US military members and quantify echocardiography evaluations, cardiac complications, and antihypertensive prescriptions in the post-2004 guideline era.

STUDY DESIGN

Using billing data from military health insurance (TRICARE) enrollees, hypertension cases were defined as 2 or more visits with a primary or unspecified hypertension diagnosis during any calendar year or 1 such visit if with a cardiologist or nephrologist.

RESULTS

During 2006-2011, the database contained an average 1.3 million subjects aged 2-18 years per year. A total of 16 322 met the definition of hypertension (2.6/1000). The incidence of hypertension increased by 17% between 2006 and 2011 (from 2.3/1000 to 2.7/1000; P < .001). Hypertension was more common in adolescents aged 12-18 years than in younger children (5.4/1000 vs 0.9/1000). Among patients with hypertension, 5585 (34%) underwent echocardiography. The frequency of annual echocardiograms increased from 22.7% to 27.7% (P < .001). In patients with echocardiography, 8.0% had left ventricular hypertrophy or dysfunction. Among the patients with hypertension, 6353 (38.9%) received an antihypertensive medication.

CONCLUSION

The prevalence of hypertension in children has increased. Compliance with national guidelines is poor. Of pediatric patients with hypertension who receive an echocardiogram, 1 in 12 had identified cardiac complications, supporting the current recommendations for echocardiography in children with hypertension. Less than one-half of children with hypertension are treated with medication.

Cardiovascular target organ damage could have been detected in sustained pediatric hypertension

The aim of this study was to assess sustained hypertension in children and its impact on cardiovascular target organ damage (TOD). Blood pressure (BP) was measured in children in Beijing in 2009. Primary hypertension was diagnosed based on three separate visits. Hypertensive children and normotensive children were followed up in 2011. According to these evaluations, three groups were defined: sustained hypertension, non-sustained hypertension and normotensive. Cardiovascular TOD and metabolic disorders were evaluated using pulse-wave velocity (PWV), carotid intima-media thickness (cIMT), and assessments of left ventricular structure and kidney function. A total of 3032 children aged 9-15 years participated in this survey, of whom 128 were diagnosed with hypertension after three separate BP measurements. Eighty out of 128 (62.5%) hypertensive and 158 normotensive children were available for follow-up in 2011. Forty-eight children were defined as having sustained hypertension, 38 as non-sustained hypertension and 152 as normotensive. Mean levels of brachial-ankle PWV (baPWV), left ventricular mass, left ventricular mass index (LVMI) and cIMT were significantly different between the three groups (p < 0.01). Compared to normotensives, the odds ratios and 95% confidence intervals for elevated LVM and cIMT were 5.27 (1.57-17.66) and 2.88 (1.03-8.09) in the non-sustained hypertensive group, and 3.28 (1.00-10.74) and 7.25 (2.69-19.58) in the sustained hypertensive group. The children with sustained hypertension have the highest risk of developing arterial stiffness, left ventricular hypertrophy and early blood vessel endothelium damage. The indices of cIMT, LVMI and PWV were useful to identify children at high risk of cardiovascular TOD.

Increased arterial stiffness in young normotensive patients with Turner syndrome: associations with vascular biomarkers

OBJECTIVES

Factors contributing to arteriopathy in patients with Turner syndrome (TS) remain unclear. We assessed arterial stiffness in young, normotensive patients with TS and correlated arterial stiffness with vascular biomarkers, GH treatment and oestrogen exposure. Sixty-one patients with TS (mean age, 12·6 years; range 6·6-21·3 years) were matched for age and sex with 61 healthy peers. Associations between arterial stiffness and high-sensitivity C-reactive protein (hsCRP), B-type natriuretic peptide (BNP), atrial NP (ANP), plasma aldosterone/plasma renin activity (PRA), IGF1 and IGFBP3 were examined after adjusting for well-established confounders of vascular disease.

RESULTS

Carotid intima media thickness standard deviation score (SDS), arterial stiffness index SDS and incremental modulus of elasticity SDS were higher, and distensibility coefficient SDS was lower in patients with TS. The duration of GH treatment and oestrogen exposure was not associated with indices of arterial stiffness. TS patients had higher hsCRP, BNP and ANP. Plasma aldosterone/PRA, IGF1 and IGFBP3 were similar in patients and controls. Multivariable regression analyses (R(2) = 0·200-0·668, P < 0·01) showed that BNP was associated with all indices of arterial stiffness. We found that hsCRP was associated with distensibility coefficient SDS (β = -0·16, P < 0·01). TS was independently associated with increased arterial stiffness (β = 0·420-3·424, P < 0·001 for all, R(2) = 0·06-0·31).

CONCLUSIONS

Young, normotensive TS patients had increased arterial stiffness than that of healthy peers. BNP, and possibly hsCRP, was independently associated with arterial stiffness in TS. Further research will determine any causal inference of these relationships.

Ambulatory Blood Pressure Monitoring in Lean, Obese and Diabetic Children and Adolescents

AIM

To determine if children and adolescents who have obesity (Ob) or type 2 diabetes (T2DM) of relatively short duration have impaired cardiovascular function compared with lean subjects using 24-hour ambulatory blood pressure as a surrogate measure of evaluation.

METHODS

We enrolled 100 African-Caribbean subjects (45 males/55 females), mean ages 14.4-15.2 years (range 11.8-18.5 years) and Tanner stage 4.2-4.8. Mean BMI for the Ob (n = 40), T2DM (n = 39) and lean (n = 21) groups were 40.3, 34.2 and 20.8, respectively (p < 0.01, Ob and T2DM vs. lean). Mean hemoglobin A1c in lean and Ob was 5.4 and 5.5% compared to 8.8% in T2DM (p < 0.001, T2DM vs. lean and Ob). Ambulatory blood pressure was recorded every 20 min over 24 h using Spacelabs 70207.

RESULTS

Mean 24-hour, daytime and nighttime systolic blood pressure was significantly higher in Ob and T2DM compared with lean subjects (mean 24-hour 117 and 120 vs. 109 mm Hg; daytime 121 and 123 vs. 113 mm Hg; and nighttime 109 and 115 vs. 101 mm Hg; p < 0.01 for all time periods). The nocturnal systolic dip in Ob and T2DM did not differ from that of lean, whereas nocturnal diastolic dip decreased significantly in Ob and T2DM compared to lean (11.5 and 10.4 vs. 20.6 mm Hg; p < 0.01). Mean pulse pressure was significantly increased in the Ob and T2DM groups compared to lean subjects (51 and 54 vs. 45 mm Hg; p < 0.01).

CONCLUSION

Adolescent Ob and T2DM groups share adverse risk factors, which may be harbingers of adult cardiovascular events.

Management of hypertension in children and adolescents

Hypertension has been recognized as an important health issue in the pediatric population over the past years. This emphasizes the need for an organized and effective plan for diagnosis and management. This review provides information to guide physicians through a structured approach to (1) screen children for hypertension during routine visits; (2) use normative blood pressure tables for diagnosis and classification; (3) perform a clinical evaluation to identify the presence of risk factors, comorbidities and/or target organ damage; and (4) initiate an individualized plan of care that includes follow-up blood pressure measurement, therapeutic lifestyle changes and - if necessary - pharmacological therapies.

Sleep disordered breathing as measured by SRBD-PSQ and neurocognition in children with hypertension

BACKGROUND

Cognitive test performance is decreased in hypertensive adults and children, a finding postulated to represent early target-organ damage to the brain. Hypertensive children are often obese, a comorbidity associated with sleep disordered breathing (SDB), itself associated with cognitive problems; potentially confounding the relation between hypertension (HTN) and neurocognition. Our objective was to determine the association between SDB as measured by a scale and questionnaire score and neurocognition among participants enrolled in an ongoing multicenter study of cognition in children with HTN.

METHODS

Subjects completed laboratory-based neurocognitive tests. Parents and subjects completed rating scales of executive function, mood, and behavior problems. Parents completed the Sleep-Related Breathing Disorder scale of the Pediatric Sleep Questionnaire (SRBD-PSQ).

RESULTS

To date, 38 HTN subjects and 34 control subjects have completed neurocognitive testing and the SRBD-PSQ. Median SRBD-PSQ scores were similar between groups but the HTN group had a higher percentage of subjects with SRBD-PSQ scores in the range suggestive of obstructive sleep apnea (26% vs. 6%, P = 0.03). Overall, higher SRBD-PSQ scores were not significantly associated with worse performance on laboratory-based measures of executive function and other cognitive domains but were significantly associated with worse scores on rating scales of executive function as well as mood and behavior problems.

CONCLUSIONS

A larger proportion of children with HTN had scores suggestive of SDB. The results underscore the importance of using a multi-method approach in the assessment of cognition and adjusting for potential confounding effects of SDB in studies of cognition in hypertensive children.

Executive function and cerebrovascular reactivity in pediatric hypertension

Primary hypertension is associated with decreased performance on neurocognitive testing and a blunted cerebrovascular reactivity to hypercapnia. Parents of 14 children with hypertension and prehypertension completed the Behavior Rating Inventory of Executive Functions. Children underwent 24-hour ambulatory blood pressure monitoring and transcranial Doppler with reactivity measurement using time-averaged maximum mean velocity and end-tidal carbon dioxide during hypercapnia-rebreathing test. Comparing the reactivity slope for the patients to historical controls showed a statistically significant difference (t = -5.19, df = 13, P < .001), with lower slopes. Pearson correlations of the Behavior Rating Inventory of Executive Functions scores with the reactivity slopes showed a statistically significant inverse relationship with Behavioral Regulation Index (r = -.60, P = .02), Metacognition Index (r = -.40, P = .05), and the Global Executive Component (r = -.53, P = .05). Children with hypertension have decreased executive function, and this correlates to low transcranial Doppler-reactivity slopes, suggesting that the brain is a target organ in hypertensive children.

44-h ambulatory blood pressure monitoring: revealing the true burden of hypertension in pediatric hemodialysis patients

BACKGROUND

The blood pressure (BP) burden is high in pediatric hemodialysis (HD) patients and adversely affects prognosis. The aim of this study was to examine whether 44-h ambulatory BP monitoring (ABPM) provides additional relevant BP data compared with 24-h ABPM.

METHODS

ABPM was initiated at the end of the mid-week dialysis run in 13 stable pediatric HD patients and continued until the next run for 44 h. Day 1 was defined as the initial 24-h ABPM and Day 2 as the time period after that until the next dialysis run. All patients had an echocardiogram to calculate the left ventricular mass index (LVMI).

RESULTS

A higher percentage of patients were diagnosed with hypertension from the 44-h ABPM than from the 24-h ABPM. All BP indexes and loads (except nighttime diastolic load) were significantly higher on Day 2 than on Day 1. Patients with BP loads of ≥ 25 % on 44-h ABPM had significantly higher LVMI than those patients with normal BP loads. No such association was found with 24-h ABPM and LVMI. Higher interdialytic weight gain was associated with higher Day-2 nighttime systolic BP load.

CONCLUSIONS

The 44-h ABPM provides more information than the 24-h ABPM in terms of diagnosing and assessing the true burden of hypertension in pediatric HD patients. Elevated BP loads from 44-h ABPM correlate with a higher LVMI on the echocardiogram.

Ambulatory blood pressure and subclinical cardiovascular disease in patients with congenital adrenal hyperplasia: a preliminary report

OBJECTIVE

There is an increased risk of cardiovascular morbidity in children and adolescents with classical congenital adrenal hyperplasia (CAH), presumably associated with obesity, hypertension, impaired glucose tolerance and dyslipidemia. This study was designed to evaluate the metabolic and cardiovascular profile of a group of children with classical CAH from the perspective of cardiovascular risk.

METHODS

Twenty-five CAH patients and 25 healthy controls were included in the study. Metabolic and anthropometric parameters were investigated and compared in these two groups.

RESULTS

Subjects in the CAH group were shorter than the controls (p=0.001) and had higher body mass index values (p=0.033). Diastolic blood pressure (DBP) (p=0.027) and carotid intima-media thickness (CIMT) values (p=0.006) were also higher in the patient group. In 24% (n=6) of CAH patients, 24-h ambulatory BP monitoring showed arterial hypertension. CIMT was significantly higher in the hypertensive patients than in those with no hypertension (p=0.013). Twenty percent (n=5) of CAH patients had nocturnal hypertension. CIMT was significantly greater in the nocturnal hypertensive group (p=0.02). Mean systolic BP (SBP) and DBP dipping were significantly different in the CAH patients (p<0.001). CIMT correlated negatively with DBP dipping (r=-0632, p=0.037) in these patients.

CONCLUSION

These results provide additional evidence for the presence of subclinical cardiovascular disease in classical CAH patients and its relationship with hypertension.

Diet, exercise, and endothelial function in obese adolescents

BACKGROUND AND OBJECTIVES

Endothelial dysfunction is the first, although reversible, sign of atherosclerosis and is present in obese adolescents. The primary end point of this study was to investigate the influence of a multicomponent treatment on microvascular function. Additional objectives and end points were a reduced BMI SD score, improvements in body composition, exercise capacity, and cardiovascular risk factors, an increase in endothelial progenitor cells (EPCs), and a decrease in endothelial microparticles (EMPs).

METHODS

We used a quasi-randomized study with 2 cohorts of obese adolescents: an intervention group (n = 33; 15.4 ± 1.5 years, 24 girls and 9 boys) treated residentially with supervised diet and exercise and a usual care group (n = 28; 15.1 ± 1.2 years, 22 girls and 6 boys), treated ambulantly. Changes in body mass, body composition, cardiorespiratory fitness, microvascular endothelial function, and circulating EPCs and EMPs were evaluated after 5 months and at the end of the 10-month program.

RESULTS

Residential intervention decreased BMI and body fat percentage, whereas it increased exercise capacity (P < .001 after 5 and 10 months). Microvascular endothelial function also improved in the intervention group (P = .04 at 10 months; + 0.59 ± 0.20 compared with + 0.01 ± 0.12 arbitrary units). Furthermore, intervention produced a significant reduction in traditional cardiovascular risk factors, including high-sensitivity C-reactive protein (P = .012 at 10 months). EPCs were increased after 5 months (P = .01), and EMPs decreased after 10 months (P = .004).

CONCLUSIONS

A treatment regimen consisting of supervised diet and exercise training was effective in improving multiple adolescent obesity-related end points.

Intra-uterine growth restriction as a risk factor for hypertension in children six to 10 years old

Introduction

Intra-uterine growth restriction (IUGR) is present in about 3–10% of live-born newborns and it is as high as 20–30% in developing countries. Since the 1990s, it has been known that abnormalities during foetal growth may result in cardiovascular disease, including hypertension in adulthood.

Methods

This study evaluated blood pressure parameters (using ambulatory blood pressure monitoring) in children aged six to 10 years old, born as small for gestational age (SGA), and compared them to their healthy peers born as appropriate for gestational age (AGA).

Results

In the SGA group, an abnormal blood pressure level (prehypertension or hypertension) was present significantly more often than in the AGA group (50 vs 16%, p < 0.01). This relationship also occurred in association with the type of IUGR (asymmetric p < 0.01, symmetric p < 0.05).

Conclusion

In SGA children, abnormal blood pressure values occurred more frequently than in AGA children.

Blood pressure profiles 5 to 10 years after transplant in pediatric solid organ recipients

Arterial hypertension is a major risk factor for cardiovascular disease after solid organ transplantation, emphasizing the need for blood pressure (BP) monitoring. The authors studied 24-hour ambulatory BP monitoring (ABPM) parameters (index, load, dipping) and their predictive value with regard to hypertension as well as correlations with graft function and metabolic parameters such as obesity and dyslipidemias. The ABPM profiles of 111 renal, 29 heart, and 13 liver transplant recipients were retrospectively analyzed 5 to 10 years after transplant (median 5.1 years). The BP profiles among the different transplant groups were similar. The BP index and load were abnormal especially at nighttime and the nocturnal BP dipping was often blunted (in 49% to 83% of the patients). The BP variables were found to be equally valued when assessing hypertension. BP load of 50% instead of 25% seems to be a more adequate cutoff value. The BP variables correlated poorly with the metabolic parameters and kidney function. Antihypertensive medication did not notably change the ABPM profile in renal transplant recipients. Hypertension, including nocturnal hypertension, is present in children receiving solid organ transplant, underlining the importance of use of ABPM in the follow-up of these patients.

Improving detection of hypertension in girls with turner syndrome using ambulatory blood pressure monitoring

BACKGROUND/AIMS

Turner syndrome (TS) is associated with increased mortality due to cardiovascular disease and a dramatically higher rate of aortic dissection. The recognition and treatment of hypertension in this population is critical. We sought to assess the ability to detect blood pressure (BP) abnormalities comparing ambulatory blood pressure monitoring (ABPM) with conventional BP measurement methods. We hypothesized that ABPM would improve detection of hypertension and alter management strategies.

METHODS

Twenty-three girls with TS underwent BP measurements using an automated oscillometric method and a manual mercury sphygmomanometer. Twenty-four-hour ABPM was performed (Spacelabs 90217, Issaquah, Wash., USA). BP values were compared to normative data based on height and sex for ABPM, and for age, height and sex for automated oscillometric and manual measurements.

RESULTS

Five (22%) subjects were found to have ambulatory hypertension (3 of these with severe hypertension). Three subjects had prehypertension using ABPM measurements. Only 1 of the 5 patients with ambulatory hypertension was categorized as hypertensive using manual BP measurements. Twelve subjects (52%) had nocturnal hypertension. ABPM data led to a change in medical management of hypertensive patients with initiation of antihypertensive therapy.

CONCLUSIONS

ABPM is advantageous in TS, as it improves detection of hypertension, identifies those with non-dipping BP patterns, and changes medical management of patients.

Associations of the eNOS G894T gene polymorphism with target organ damage in children with newly diagnosed primary hypertension

BACKGROUND

The endothelial nitric oxide synthase (eNOS) G894T gene polymorphism is associated with the risk of primary hypertension (PH) and vascular complications in adults with PH.

METHODS

We explored the associations of the G894T polymorphism with 24-h ambulatory blood pressure, left ventricular mass (LVM), carotid intima media thickness (cIMT), urinary albumin excretion, oxidative stress and inflammatory parameters in 126 children with newly diagnosed PH and in 83 healthy children.

RESULTS

Among the 126 children with PH 92 (73%) had ambulatory hypertension and 34 (27%) had severe ambulatory hypertension. Left ventricular hypertrophy (LVH) was detected in 39 (31%) patients, cIMT of >2 standard deviation scores in 21 (16.6%) patients, albuminuria of >30 mg/24 h in 18 (14.3%) patients and metabolic syndrome (MS) in 22 (17.5%) patients. The frequency of the T allele was 52.4% in the PH group and 54.2% in the control group (not significant), and in both groups the frequency of the T allele was consistent with the Hardy-Weinberg equilibrium. Compared with G allele carriers, hypertensive T allele carriers had increased cIMT (p < 0.05) and more severe albuminuria (not significant, p = 0.1); there was no difference between the groups in hypertension severity and LVM. T and G allele distribution did not differ between patients with and without metabolic syndrome. No significant correlations between the assessed parameters and the eNOS G894T gene polymorphism were found in the controls, although T allele carriers tended to have an increased cIMT (p = 0.09).

CONCLUSION

The eNOS T allele is not more prevalent among hypertensive children than among healthy ones, but it is associated with early vascular damage in children with PH, independent of metabolic abnormalities. No associations between the eNOS G894T polymorphism and metabolic abnormalities were found.

Essential hypertension vs. secondary hypertension among children

BACKGROUND

The aim was to determine the proportions and correlates of essential hypertension among children in a tertiary pediatric hypertension clinic.

METHODS

We evaluated 423 consecutive children and collected demographic and clinical history by retrospective chart review.

RESULTS

We identified 275 (65%) hypertensive children (blood pressure >95th percentile per the "Fourth Report on the Diagnosis, Evaluation, and Treatment of High Blood Pressure in Children and Adolescents") from 423 children referred to the clinic for history of elevated blood pressure. The remainder of the patients had normotension (11%), white coat hypertension (11%), prehypertension (10%), and pending diagnosis (3%). Among the 275 hypertensive children, 43% (n = 119; boys = 56%; median age = 12 years; range = 3-17 years) had essential hypertension and 57% (n = 156; boys = 66%; median age = 9 years; range = 0.08-19 years) had secondary hypertension. When compared with those with secondary hypertension, those with essential hypertension had a significantly older age at diagnosis (P = 0.0002), stronger family history of hypertension (94% vs. 68%; P < 0.0001), and lower prevalence of preterm birth (20% vs. 46%; P < 0.001). There was a bimodal distribution of age of diagnosis in those with secondary hypertension.

CONCLUSIONS

The phenotype of essential hypertension can present as early as 3 years of age and is the predominant form of hypertension in children after age of 6 years. Among children with hypertension, those with essential hypertension present at an older age, have a stronger family history of hypertension, and have lower prevalence of preterm birth.

Cognitive function in hypertensive children

Young hypertensive adults demonstrate decreased performance on neurocognitive testing compared with that of normotensive controls. There is emerging, preliminary evidence that children with hypertension also manifest cognitive differences when compared to normotensive controls. These preliminary studies consist mostly of database and single-center studies that focus primarily on differences in neurocognitive test performance and differences in cerebrovascular reactivity between hypertensive and normotensive subjects. Lessons from the literature on cognition in adult hypertensives and experience from the preliminary studies in children informed the design of a current, multicenter, ongoing study of cognition in children with primary hypertension.

Is the serum level of salusin-β associated with hypertension and atherosclerosis in the pediatric population?

BACKGROUND

Salusins are recently identified endogenous bioactive peptides that have hypotensive and bradycardiac effects. Salusin-β is involved in the pathogenesis of human atherosclerosis.

METHODS

This was a prospective cohort study of a young patient population with hypertension (HTN). Based on ambulatory blood pressure monitoring (ABPM), the adolescents were categorized into two groups, namely, a hypertensive group consisting of patients with essential (primary) HTN (HTN group) and a group consisting of patients with white-coat HTN [reference (R) group]. Correlations between serum salusin-β level and clinical, laboratory and ambulatory blood pressure (BP) variables were assessed.

RESULTS

The median salusin-β concentration was significantly higher in patients with essential HTN than in those with white-coat HTN (R group). Salusin-β was positively correlated with the body mass index Z-score, systolic and diastolic blood pressure (BP) from three independent measurements, mean systolic BP during the daytime, triglyceride (TG) level, and atherogenic index (TG/high-density lipoprotein-cholesterol ratio).

CONCLUSIONS

The results of this preliminary study suggest that salusin-β may play an important role in the pathogenesis of HTN in a young population. Further research should focus on the role of salusin-β in the mechanism of essential HTN and the assessment of possible correlations between salusin-β and other well-known markers of atherosclerosis in both teenagers and adults. This research should serve as a base for future studies in this field.

High waist circumference is associated with elevated blood pressure in non-Hispanic White but not Hispanic children in a cohort of pre-adolescent children

BACKGROUND

Hispanics comprise the most rapidly growing demographic in the US, but little is known about the cardiometabolic risk factors in Hispanic children. This study examined the association of high waist circumference (WC) and elevated blood pressure by race/ethnicity in a cohort of 9 to 13 year olds in New Haven, CT (n = 824).

METHODS

WC, overweight status and blood pressure were measured in 2009, with follow-up in 2011.

RESULTS

Logistic regression revealed that Hispanic children had increased likelihood of elevated blood pressure at follow-up. High baseline WC was associated with increased likelihood of elevated blood pressure for non-Hispanic White but not Hispanic or non-Hispanic Black pre-adolescents, controlling for baseline age, gender, overweight, and blood pressure.

CONCLUSION

Potential racial/ethnic differences in the association between high WC and elevated blood pressure may impact identification of children at risk for elevated blood pressure, especially among Hispanics.

A longitudinal retrospective analysis of left ventricular mass in a cohort of pediatric kidney transplant recipients

Childhood end-stage kidney disease is associated with increased risk for early adulthood cardiovascular (CV) morbidity and mortality. Increased LVM is an early indicator of CV disease. Previous studies have suggested that LVM decreases after kidney transplantation; however, trends have been inconsistent. A single center retrospective longitudinal cohort analysis of LVM, documented annually, starting before kidney transplantation for up to 10 yr after transplantation was performed. BP documented by annual 24-h ambulatory monitoring studies, and BMI values were also reviewed. Twenty-seven children followed for a mean period of 5.3 yr were included. Depending on definition of LVH, its prevalence pretransplant and in the first years post-transplant was up to 33% dropping to 0-25% thereafter. Individual longitudinal LVM z-score trends were highly variable but generally trended toward the mean immediately after transplant and toward negative values in the following years. BP was stable during the follow-up period while mean annual BMI increased in the first-year post-transplant but declined thereafter. In a cohort of pediatric renal transplant recipients, prevalence of LVH decreased after transplant; however, individual longitudinal LVM trends were highly variable among patients. Prospective studies are needed to correlate individual LVM trends with outcomes.

Comparison of calf and brachial blood pressures in infants: is there a difference between calf and brachial blood pressures?

The standard of care is to obtain a noninvasive blood pressure (NIBP) measurement from the right upper arm. However, in the pediatric population it is common practice to take blood pressure (BP) measurements from the calf/upper ankle. Nurses commonly take calf NIBPs for many reasons, but there is little evidence to support calf BPs as a reliable site for BP measurement. Furthermore, there is conflicting evidence. Some studies suggest no difference between the calf and the upper arm BPs, whereas others conclude great variability between the two. The purpose of this study was to demonstrate the reliability of calf BPs, by showing no difference between brachial and calf BP measurements in neonates and infants ≤ 1 year old. From July 2008 to December 2008, a convenience sample of 52 subjects admitted to the Neonatal and Infant Critical Care Unit were enrolled into the study. Limb selection was not randomized. Three BPs were taken from the arm and 3 BPs were taken from the calf. Data were analyzed using a mixed analysis of variance (P = 0.05). The difference was not significant for systolic (P = 0.6159) or mean BP (P = 0.1298), but it was significant for diastolic (P = 0.0263). The authors concluded that these results support the current practice of bedside nurses and contribute to the limited knowledge on this topic. Because there was a difference in the diastolic BPs, further investigation is needed.

Ambulatory blood pressure monitoring is recommended in the clinical management of children with a solitary functioning kidney

BACKGROUND

Children with a solitary functioning kidney are at increased risk of developing chronic kidney disease. Hypertension may be an early indicator of renal dysfunction in these patients. We determined blood pressure (BP) profiles of children with a solitary functioning kidney by using ambulatory BP monitoring (ABPM).

METHODS

To assess the occurrence with (pre)hypertension, we compared ABPM to office BP measurement in 47 children with a solitary functioning kidney. None of the subjects used antihypertensive agents or had been hypertensive during previous clinical visits.

RESULTS

Mean age of study subjects was 12.7 (±3.3) years. Hypertension was identified in ten (21 %) subjects with ABPM, whereas only two (4 %) children were hypertensive during office BP measurement (p < 0.01). Fifteen (32 %) children had an ABPM standard deviation (SD) value ≥90th percentile versus six (13 %) subjects based on office BP measurement (p = 0.051). Although 24-h ABPM SD scores were higher in the congenital type than in the acquired type of solitary functioning kidney (p ≤ 0.01), the proportions of subjects with 24-h ABPM hypertension were similar between groups (congenital 25 % versus acquired 16 %; p = NS).

CONCLUSIONS

Based on ABPM, one in five children with a solitary functioning kidney has hypertension. As the majority of these subjects were not hypertensive during office BP measurements, ABPM should be considered in the clinical management of solitary functioning kidney patients.

Cardiorespiratory fitness, respiratory function and hemodynamic responses to maximal cycle ergometer exercise test in girls and boys aged 9-11 years: the PANIC Study

PURPOSE

We aimed to provide comprehensive data on and reference values for cardiorespiratory fitness, respiratory function and hemodynamic responses during and after maximal cycle ergometer test in children.

METHODS

The participants were a population sample of 140 children (69 girls) aged 9-11 years. Heart rate (HR) and systolic blood pressure (SBP) were measured from pre-exercise rest to the end of recovery. Respiratory gases were measured directly by the breath-by-breath method. Peak workload, HR changes, peak oxygen uptake (VO2), peak oxygen pulse (O2 pulse), peak respiratory exchange ratio (RER) and the lowest ratio of ventilation and carbon dioxide output (VE/VCO2) during the exercise test in girls and boys were presented according to their distributions in 5 categories.

RESULTS

HR decreased more during 4-min recovery in boys than in girls (76 vs. 67 beats/min, p < 0.001), whereas SBP decrease was similar in boys and girls (30 vs. 22 mmHg, p = 0.66). Boys had a higher peak VO2 per weight [51.9 vs. 47.6 ml/kg/min, p < 0.001] and per lean mass [67.3 vs. 63.0 ml/kg/min, p < 0.001] than girls. Peak O2 pulse per lean mass was higher in boys than in girls (0.34 vs. 0.31 ml/kg/beat, p < 0.001). There was no difference in the lowest VE/VCO2 during the test between boys and girls (28 vs. 29, p = 0.18).

CONCLUSIONS

The indicators of cardiorespiratory fitness were better in boys than in girls. These data enable the evaluation of cardiorespiratory function during and after maximal exercise test and the detection of children with abnormal values.