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

Everyday Discrimination Prospectively Predicts Blood Pressure Across 10 Years in Racially/Ethnically Diverse Midlife Women: Study of Women's Health Across the Nation

BACKGROUND

Interpersonal discrimination is linked to greater risk for cardiovascular disease (CVD) and this association varies by race/ethnicity.

PURPOSE

To examine whether exposure to everyday discrimination prospectively predicts elevated blood pressure (BP), whether this association differs by race/ethnicity, and is mediated by adiposity indices.

METHODS

Using data for 2,180 self-identified White, Black, Chinese, Japanese, and Hispanic participants from the Study of Women's Health Across the Nation, we examined associations among exposure to (higher vs. lower) everyday discrimination at baseline and BP and hypertension (HTN; systolic blood pressure [SBP] ≥ 140 mmHg; diastolic blood pressure [DBP] ≥ 90 mmHg; or self-reported HTN medication use) risk over a 10 year period. Additionally, we used the bootstrap method to assess repeated, time-varying markers of central and overall adiposity (waist circumference and body mass index [BMI] (kg/m2), respectively) as potential mediators.

RESULTS

Exposure to everyday discrimination predicted increases in SBP and DBP over time, even after adjusting for known demographic, behavioral, or medical risk factors. However, greater waist circumference or BMI (examined separately) mediated these observations. Notably, there were no racial/ethnic differences in the observed association and HTN risk was not predicted.

CONCLUSIONS

The current findings suggest that everyday discrimination may contribute to elevated BP over time in U.S. women, in part, through increased adiposity. These findings demonstrate the complexity of the linkage of discrimination to CVD risk and raise the need to closely examine biobehavioral pathways that may serve as potential mediators.

Diurnal blood pressure loads are associated with lower cognitive performances in controlled-hypertensive elderly individuals

INTRODUCTION

Hypertension in midlife adults is associated with cognitive decline later in life. In individuals treated for hypertension, blood pressure (BP) loads have been associated with end organ damages. This study examines whether BP load inversely correlates with performance in cognitive tasks in normotensive or controlled hypertensive (CHT) individuals.

METHODS

Participants between 60 and 75 years old were divided into normotensive participants who did not receive antihypertensive treatment (n = 49) and CHT patients (n = 28). They were evaluated for BP using ambulatory blood pressure monitoring and cognitive functions with tests assessing cognitive flexibility, working and episodic memory, and processing speed.

RESULTS

Analysis of covariance between normotensive and CHT participants revealed lower cognitive performances on immediate and delayed recall and total number of words of the Rey Auditory Verbal Learning Test (P < 0.001). Spearman's correlations between BP loads and cognitive performances revealed inversed associations between diurnal systolic (SBP) loads and performances on the Trail Making Test Part B (TMTB) (P = 0.009), the TMTB-TMT Part A (P = 0.013), the Switching Cost of the color-word interference test (P = 0.020) and the Digit-Symbol Substitution Score tests (P = 0.018) in CHT. Diurnal diastolic (DBP) loads were inversely correlated to the TMTB (P = 0.014) and TMTB-TMT Part A (P = 0.006). In normotensive subjects, diurnal SBP loads were associated with the delayed recall of the Rey Auditory Verbal Learning Test (P = 0.031) and to the three components of the digit span (P < 0.05).

CONCLUSION

Diurnal BP loads are associated with lower cognitive performances in CHT individuals. These results suggest a lowering of target levels of diurnal BPs and/or its variability.

Isolated nocturnal and isolated daytime hypertension associate with altered cardiovascular morphology and function in children with chronic kidney disease: findings from the Cardiovascular Comorbidity in Children with Chronic Kidney Disease study

INTRODUCTION

Prevalence of isolated nocturnal hypertension (INH) and isolated daytime hypertension (IDH) is around 10% in adults. Data in children, especially in chronic kidney disease (CKD), are lacking. The aim of this cross-sectional multicenter cohort study was to define the prevalence of INH and IDH and its association with cardiovascular morphology and function, that is, pulse wave velocity (PWV), carotid intima-media thickness (cIMT), or left ventricular mass index (LVMI) in children with CKD.

METHODS

Ambulatory blood pressure (BP) monitoring profiles were analyzed in 456 children with CKD stages III-V participating in the Cardiovascular Comorbidity in Children with Chronic Kidney Disease Study (64.3% males, 71.3% congenital anomaly of the kidney and urinary tract, age 12.5 ± 3.2 years, estimated glomerular filtration rate 29 ± 12 ml/min per 1.73 m). Baseline PWV, cIMT, and LVMI were compared in normotension, INH, IDH, or sustained 24-h hypertension.

RESULTS

Prevalence of sustained hypertension was 18.4%, of INH 13.4%, and of IDH 3.7%. PWV SDS (SD score) and cIMT SDS were significantly higher in sustained hypertension and INH, and PWV SDS was significantly higher in IDH, compared with normotension. LVMI was significantly increased in sustained hypertension, but not in INH or IDH. Determinants of INH were smallness for gestational age, older age, higher height SDS and parathyroid hormone, and shorter duration of CKD. In logistic regression analysis, day/night-time hypertension or ambulatory BP monitoring pattern (normal, INH, IDH, sustained hypertension) were independently associated with cardiovascular outcome measures: elevated night-time BP was associated with increased cIMT, PWV, and left ventricular hypertrophy; INH was associated with cIMT.

CONCLUSION

INH is present in almost one out of seven children with predialysis CKD; INH and nocturnal hypertension in general are associated with alterations of arterial morphology and function.

In newly diagnosed hypertensive children, increased arterial stiffness and reduced heart rate variability were associated with a non-dipping blood pressure pattern

OBJECTIVES

This study was designed to investigate the differences in pulsatile hemodynamics, echocardiographic findings, 24-h Holter monitoring and heart rate variability parameters of dipper patterns in children with newly diagnosed essential hypertension.

METHODS

This study included 30 children with newly diagnosed essential hypertension and 30 healthy controls. The essential hypertension cohort was divided into dippers and non-dippers. Physical examinations, 24-hour ambulatory blood pressure monitoring, 24-h Holter monitoring, 24-h heart rate variability, conventional 2-dimensional and Doppler echocardiography, and tissue Doppler imaging were performed. Pulse wave analysis using an oscillometric monitor was conducted to measure augmentation index (AIx) and pulse wave velocity (PWV).

RESULTS

In patients with essential hypertension, left ventricular (LV) wall thickness and LV mass index were increased. There were no significant differences in LV mass index and LV wall thickness based on the dipping patterns. Time domain values and the standard deviation of all RR intervals (SDNN) were substantially lower in the essential hypertension group. SDNN values were considerably lower in the non-dipper group compared with the dipper group. In terms of frequency domain measures, low frequency measured in daytime values was much lower in the essential hypertension group compared with the control. The dipper patterns revealed that low frequency measured in nighttime values was also substantially lower in the non-dipper group. Pulse wave analysis and AIx values were notably higher in the essential hypertension patient group and those with non-dipper status.

CONCLUSION

SDNN values, which reflect parasympathetic activity, were markedly lower in children with hypertension and the non-dipper group than healthy controls and the dipper group, respectively. Also, parameters related to arterial stiffness, such as PWV and AIx values were significantly higher in children with hypertension and the non-dipper group.

Nocturnal blood pressure dipping as a marker of endothelial function and subclinical atherosclerosis in pediatric-onset systemic lupus erythematosus

Background

Loss of the normal nocturnal decline in blood pressure (BP), known as non-dipping, is a potential measure of cardiovascular risk identified by ambulatory blood pressure monitoring (ABPM). We sought to determine whether non-dipping is a useful marker of abnormal vascular function and subclinical atherosclerosis in pediatric-onset systemic lupus erythematosus (pSLE).

Methods

Twenty subjects 9–19 years of age with pSLE underwent ABPM, peripheral endothelial function testing, carotid-femoral pulse wave velocity/analysis for aortic stiffness, and carotid intima-media thickness. We assessed the prevalence of non-dipping and other ABPM abnormalities. Pearson or Spearman rank correlation tests were used to evaluate relationships between nocturnal BP dipping, BP load (% of abnormally elevated BPs over 24-h), and vascular outcome measures.

Results

The majority (75%) of subjects had inactive disease, with mean disease duration of 3.2 years (± 2.1). The prevalence of non-dipping was 50%, which occurred even in the absence of nocturnal or daytime hypertension. Reduced diastolic BP dipping was associated with poorer endothelial function (r 0.5, p = 0.04). Intima-media thickness was significantly greater in subjects with non-dipping (mean standard deviation score of 3.0 vs 1.6, p = 0.02). In contrast, higher systolic and diastolic BP load were associated with increased aortic stiffness (ρ 0.6, p = 0.01 and ρ 0.7, p < 0.01, respectively), but not with endothelial function or intima-media thickness.

Conclusion

In a pSLE cohort with low disease activity, isolated nocturnal BP non-dipping is prevalent and associated with endothelial dysfunction and atherosclerotic changes. In addition to hypertension assessment, ABPM has a promising role in risk stratification and understanding heterogeneous mechanisms of cardiovascular disease in pSLE.

Management of adults with coarctation of aorta

Coarctation of the aorta (CoA) is a relatively common congenital cardiac defect often causing few symptoms and therefore can be challenging to diagnose. The hallmark finding on physical examination is upper extremity hypertension, and for this reason, CoA should be considered in any young hypertensive patient, justifying measurement of lower extremity blood pressure at least once in these individuals. The presence of a significant pressure gradient between the arms and legs is highly suggestive of the diagnosis. Early diagnosis and treatment are important as long-term data consistently demonstrate that patients with CoA have a reduced life expectancy and increased risk of cardiovascular complications. Surgical repair has traditionally been the mainstay of therapy for correction, although advances in endovascular technology with covered stents or stent grafts permit nonsurgical approaches for the management of older children and adults with native CoA and complications. Persistent hypertension and vascular dysfunction can lead to an increased risk of coronary disease, which, remains the greatest cause of long-term mortality. Thus, blood pressure control and periodic reassessment with transthoracic echocardiography and three-dimensional imaging (computed tomography or cardiac magnetic resonance) for should be performed regularly as cardiovascular complications may occur decades after the intervention.

A Case-Control Study of Salivary Redox Homeostasis in Hypertensive Children. Can Salivary Uric Acid be a Marker of Hypertension?

Oxidative stress plays a critical role in the pathogenesis of hypertension; however, there are no data on salivary redox homeostasis and salivary gland function in children with hypertension. A total of 53 children with hypertension and age- and sex-matched controls were classified for the study. The antioxidant barrier and oxidative/nitrosative stress were evaluated in non-stimulated (NWS) and stimulated (SWS) whole saliva, plasma, and erythrocytes, with Student's t-test and Mann-Whitney U-test used for statistical analysis. We demonstrated that the activities of superoxide dismutase, catalase, and peroxidase were significantly higher in NWS, SWS, and erythrocytes of children with hypertension, similar to oxidative damage in proteins (advanced glycation end products) and lipids (malondialdehyde) as well as nitrosative stress markers (peroxynitrite and nitrotyrosine). The level of uric acid (UA) was significantly higher in NWS, SWS, and plasma of children with hypertension. UA concentration in SWS correlated positively with systolic and diastolic blood pressure and UA content in plasma. This parameter differentiates children with hypertension from healthy controls (AUC = 0.98) with a high degree of sensitivity (94%) and specificity (94%). Stimulated salivary flow was significantly lower in the hypertension group, similar to total protein content and salivary amylase activity. In summary, childhood hypertension is associated with hyposalivation as well as disturbances in antioxidant defense and enhanced oxidative/nitrosative damage both in the plasma/erythrocytes as well as saliva. Salivary UA may be a potential biomarker of hypertension in children.

Prognostic Value of Ambulatory Blood Pressure Load in Pediatric CKD

BACKGROUND AND OBJECTIVES

Elevated BP load is part of the criteria for ambulatory hypertension in pediatric but not adult guidelines. Our objectives were to determine the prevalence of isolated BP load elevation and associated risk with adverse outcomes in children with CKD, and to ascertain whether BP load offers risk discrimination independently or in conjunction with mean ambulatory BPs.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We studied 533 children in the CKD in Children (CKiD) Study to determine the prevalence of normotension, isolated BP load elevation (≥25% of all readings elevated but mean BP normal), and ambulatory hypertension. We examined the association between these categories of BP control and adverse outcomes (left ventricular hypertrophy [LVH] or ESKD). We used c-statistics to determine risk discrimination for outcomes by BP load used either independently or in conjunction with other BP parameters.

RESULTS

Overall, 23% of the cohort had isolated BP load elevation, but isolated BP load elevation was not statistically significantly associated with LVH in cross-section (odds ratio, 1.8; 95% CI, 0.8 to 4.2) or time to ESKD (hazard ratio, 1.2; 95% CI, 0.7 to 2.0). In unadjusted cross-sectional analysis, every 10% higher systolic BP load was associated with 1.1-times higher odds of LVH (95% CI, 1.0 to 1.3), but discrimination for LVH was poor (c=0.61). In unadjusted longitudinal analysis, every 10% higher systolic BP load was associated with a 1.2-times higher risk of ESKD (95% CI, 1.1 to 1.2), but discrimination for ESKD was also poor (c=0.60). After accounting for mean systolic BP, systolic BP load was not statistically significantly associated with either LVH or ESKD. Findings were similar with diastolic BP load.

CONCLUSIONS

BP load does not provide additive value in discriminating outcomes when used independently or in conjunction with mean systolic BP in children with CKD.

PODCAST

This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2020_03_11_CPOD10130819.mp3.

Changes in Ambulatory Blood Pressure Phenotype over Time in Children and Adolescents with Elevated Blood Pressures

OBJECTIVE

To determine the stability of ambulatory blood pressure monitoring (ABPM) over time in children referred for evaluation of elevated BPs and assess for factors predicting change.

STUDY DESIGN

This retrospective chart review conducted at Seattle Children's Hospital and University of Pittsburgh Medical Center Children's Hospital of Pittsburgh identified 124 children referred for elevated BPs with 2 ABPM studies at least 6 months apart. All subjects received lifestyle counseling. Subjects with secondary hypertension (HTN) or on antihypertensive medication were excluded. ABPM phenotype was classified using American Heart Association guidelines as showing normal BP, prehypertension, and HTN. Generalized linear mixed effect regression models were used to regress stable, improving, or worsening HTN outcomes at study follow-up on baseline BP index and load variables.

RESULTS

The median age of patients was 14.1 years (73% males) and the median interval between studies was 18 months. ABPM phenotype changed in 58 of 124 children, with 16% worsening and 31% improving. Older age was associated with persistence of HTN. Although not significant, decrease in body mass index z-score tracked with sustained normal ambulatory BPs.

CONCLUSIONS

Although the sample size is small, our study suggests ABPM phenotype shows variability over time. Further study is required to identify factors supporting risk for progression of ABPM phenotype over time.

Predictive Model for Ambulatory Hypertension Based on Office Blood Pressure in Obese Children

Background: The epidemic of obesity, along with hypertension (HT) and cardiovascular disease, is a growing contributor to global disease burden. It is postulated that obese children are predisposed to hypertension and subsequent cardiovascular disease in adulthood. Early detection and management of hypertension in these children can significantly modify the course of the disease. However, there is a paucity of studies for the characterization of blood pressure in obese children through ambulatory blood pressure monitoring (ABPM), especially in the developing world. This study aims to characterize ambulatory blood pressure in obese children and to explore feasibility of using office BP that will predict ambulatory hypertension. Methods:In the present study, 55 children with a body mass index (BMI) in the ≥95th percentile for age and sex were enrolled in a tertiary care hospital and underwent 24 h of ABPM and detailed biochemical investigations. Results:Ambulatory hypertension was recorded in 14/55 (25.5%; white coat hypertension in 17/29 (58.6%) and masked hypertension in 2/26 (7.69%). For office SBP percentile the area under curve (AUC) was 0.773 (95% CI: 0.619-0.926, p = 0.005) and for office DBP percentile the AUC was 0.802 (95% CI: 0.638-0.966, p = 0.002). The estimated cut offs (Youden's index) for office blood pressure which predicts ambulatory hypertension in obese children were the 93rd percentile for systolic BP (sensitivity-67% and specificity-78%) and the 88th percentile for diastolic BP (sensitivity-83% and specificity-62%). Conclusion:Ambulatory blood pressure abnormalities are highly prevalent among children with obesity. Office blood pressure did not accurately predict ambulatory hypertension. More than half of the children labeled as "hypertension" on office blood pressure measurement in the study were diagnosed to have white coat hypertension (WCH), thus emphasizing the role of ABPM for evaluation of WCH before the child is subjected to detailed investigations or started on pharmacotherapy.

Does the duration of ambulatory blood pressure measurement matter in diagnosing arterial hypertension in children?

OBJECTIVES

The aim of our study was to establish if 48-hour ambulatory blood pressure monitoring (ABPM) is more reliable than 24-hour monitoring in order to reduce the impact of external factors on blood pressure (BP) in children.

METHODS

Two hundred fifteen children with indications for ABPM underwent 48-hour ABPM. In the first part of the study, the values of systolic BP (SBP), diastolic BP (DBP) and heart rate between the first 24 hours and the total 48 hours were compared. In the second part, the same parameters between the first and second 24 hours were compared. In the third part, we determined whether the differences in measurements between the first and second 24 hours had clinical significance and meant a change of diagnosis.

RESULTS

The results of the first part of the study showed no statistically significant differences. In the second part, the average values of SBP and DBP were statistically significantly higher during the first 24 hours as compared with the second 24 hours. In the second 24 hours, more children had normal BP (NBP) and a smaller number of them had high NBP or arterial hypertension (AH) compared with the first 24 hours, suggesting that this has clinical significance.

CONCLUSIONS

Within certain limits, the results of our study suggest that 48-hour ABPM is more reliable than 24-hour ABPM, where especially the second 24 hours are a period of measurement that should be taken into consideration for this purpose. These results could impact the diagnostics of AH in children.

Obstructive sleep apnea and hypertension in pediatric chronic kidney disease

BACKGROUND

Children with chronic kidney disease (CKD) are at risk for obstructive sleep apnea (OSA) and hypertension. The objectives of this study were to explore associations between OSA severity using the apnea-hypopnea-index(AHI) and obstructive apnea-hypopnea-index(OAHI) on polysomnography (PSG), OSA symptoms, and measures of hypertension in children with CKD.

METHODS

One-night in-laboratory PSGs and 24-h ambulatory blood pressure monitoring (ABPM) were performed on children with CKD stages 2-5 (non-dialysis dependent). Sleep questionnaires, including the modified Epworth Sleepiness Scale (ESS) and the Pediatric Sleep Questionnaire (PSQ), were administered during the sleep study.

RESULTS

Nineteen children and adolescents completed a PSG and questionnaires and thirteen completed ABPMs. Mean (standard deviation) age at the time of the sleep study was 14.1 (3.2) years. Eleven (58%) participants had CKD stage two, and eight (42%) had stage 3-4. None of the participants were found to have OSA on PSG. One participant had a positive ESS score (≥ 11) and five participants had positive PSQ scores (≥  eight). Night systolic and diastolic pressures were strongly correlated with the OAHI (r = 0.67 and r = 0.69, respectively, p < 0.05), while the AHI was not correlated with any blood pressure measures.

CONCLUSIONS

Our study did not find OSA on PSG in children with predominantly mild to moderate CKD. The OAHI was found to be strongly correlated with nighttime blood pressures. Future prospective studies with a larger sample size are needed to monitor for potential progression of symptoms and findings on PSG in pediatric patients as they evolve across the spectrum of CKD.

The Relationship between the Waist Circumference and Increased Carotid Intima Thickness in Obese Children

Background: This study aimed to evaluate the cardiometabolic risk factors in normotensive obese and hypertensive obese (HT-obese) children by comparison of anthropomorphic measurements, fat distribution, carotid artery intima-media thickness (CIMT), and inflammatory markers. Methods: Fifty-three obese patients 10-18 years of age with a BMI-for-age/gender >95th percentile and 20 age- and gender-matched healthy volunteers enrolled in the study. Obese patients were divided into two groups according to the presence of hypertension (HT), as follows: HT-obese subgroup (n = 30) and nonhypertensive obese (non-HT-obese) subgroup (n = 23). Results: Weight standard deviation score (SDS), BMI-SDS, waist circumference (WC) SDS, and the fat tissue z-score were significantly higher (p < 0.001 for all) in the obese patients than the control groups. Obese patients had higher 24-hour systolic blood pressure (SBP) SDS and leptin, high-sensitivity C-reactive protein, tumor necrosis factor-alpha, and interleukin-6 levels. Furthermore, CIMT and CIMT-SDS were significantly higher in them. HT-obese patients (n = 30) had significantly higher WC-SDS and lower serum leptin and adiponectin levels than those of non-HT-obese group (n = 23). Finally, an association between increased CIMT-SDS and WC-SDS (β = 0.399, p = 0.002) and 24-hour SBP-SDS (β = 0.272, p = 0.009) was shown. Conclusions: Association between increased WC and HT implies the importance of central obesity in atherosclerosis. We concluded that WC measurement could be used to define risk groups since it is related to cardiometabolic complications.

Cardiovascular disease risk among children with focal segmental glomerulosclerosis: a report from the chronic kidney disease in children study

BACKGROUND

The aims were to compare the cardiovascular disease (CVD) risk among children with chronic kidney disease (CKD) secondary to focal segmental glomerulosclerosis (FSGS) with the CVD risk of children with CKD due to other diagnoses.

METHODS

Casual blood pressure (BP), ambulatory blood pressure monitoring (APBM), echocardiogram, lipids, carotid intima medial thickness (cIMT), and uric acid obtained from participants in the Chronic Kidney Disease in Children (CKiD) cohort were analyzed longitudinally. Seventy-nine children with FSGS (FSGS-CKD) were compared to 196 children with non-FSGS glomerular disease (GDO-CKD) and 616 children with non-glomerular disease (NG-CKD).

RESULTS

At baseline, FSGS-CKD (median 14 years) had ambulatory hypertension (24.6%), masked hypertension (46.2%), left ventricular hypertrophy (LVH) (26.3%), and dyslipidemia (60.0%). In adjusted models, FSGS-CKD had higher systolic BP z-score (0.52 vs 0.11 and 0.23, p = 0.002 and 0.02), triglycerides (133 vs 109 and 102 mg/dl, p = 0.007 and < 0.001), and non-high density lipoprotein (144 vs 132 and 119 mg/dl, p = 0.07 and < 0.001) at baseline when compared to GDO-CKD and NG-CKD, respectively. Left ventricular mass index (LVMI) (36.0 vs 31.7 g/m^2.7, p < 0.001) and the odds of LVH (OR 3.38, 95% CI 1.42, 8.08) at baseline were greater in FSGS-CKD compared to NG-CKD. Adjusted longitudinal analysis showed that FSGS-CKD had a faster decline in LVMI than NG-CKD, and FSGS-CKD had a faster increase in uric acid compared to both groups.

CONCLUSIONS

Children with CKD due to FSGS had a relatively high prevalence of CVD risk factors. FSGS was associated with greater CVD risk when compared to other CKD diagnoses.

Ambulatory Blood Pressure Monitoring in Pediatrics

PURPOSE OF REVIEW

This is a review of ambulatory blood pressure monitoring (ABPM) use in pediatrics, summarizing current knowledge and uses of ABPM.

RECENT FINDINGS

Updated guidelines from the American Academy of Pediatrics have emphasized the value of ABPM. ABPM is necessary to diagnose white coat hypertension, masked hypertension, and nocturnal hypertension associated with specific conditions. There is growing evidence that ABPM may be useful in these populations. ABPM has been demonstrated to be more predictive of end-organ damage in pediatric hypertension compared to office blood pressure. ABPM is an important tool in the diagnosis and management of pediatric hypertension. Routine use of ABPM could potentially prevent early cardiovascular morbidity and mortality in a wide variety of populations.

Ambulatory blood pressures and central blood pressures are associated with cardiovascular morbidity in adolescent and young adult patients receiving chronic hemodialysis

BACKGROUND

Left ventricular hypertrophy (LVH) and arterial stiffness measured by pulse wave velocity (PWV) are independent predictors of cardiovascular (CV) mortality in adults receiving chronic dialysis. Hypertension strongly associates with elevated left ventricular mass index (LVMI) and PWV, with ambulatory blood pressure monitoring (ABPM), and central blood pressure (CBP) superior to office blood pressures (BP) in predicting CV morbidity. Few studies have described associations of office BP, ABPM, and CBP with LVMI and PWV in adolescent and young adult patients receiving hemodialysis (HD).

METHODS

Cross-sectional study of 22 adolescents and young adults receiving chronic HD. Pre- and post-dialysis office BP and CBP using applanation tonometry were obtained. Twenty-four-hour ABPM was obtained midweek post-dialysis. Pre- and post-dialysis carotid-brachial PWV were obtained same day as BP measurements. Annual echocardiograms for standard care were reviewed for LVH.

RESULTS

Pre-dialysis CBP index correlated with LVMI (r = 0.3, p = 0.04) and PWV (r = 0.48, p = 0.02). Hypertensive patients identified by ABPM had worse LVMI; daytime ABPM systolic BP index correlated with LVMI (r = 0.5, p = 0.02). Office BP was not associated with LVMI; only office diastolic BP was associated with PWV (r = 0.46, p = 0.02). There was no correlation of LVMI or PWV with bone health parameters, anemia, interdialytic weight gain, or residual renal function.

CONCLUSIONS

Ambulatory blood pressure monitoring is superior to casual office BP obtained at time of dialysis in delineating cardiovascular morbidity in adolescent and young adult HD patients. CBP is easily performed and correlates with LVMI and PWV in adolescent and young adult HD patients; however, large-scale normative data is needed.

Home Blood Pressure Monitoring in Children and Adolescents: Systematic Review of Evidence on Clinical Utility

PURPOSE OF REVIEW

For the accurate diagnosis and management of hypertension, out-of-office blood pressure evaluation using ambulatory (ABPM) or home monitoring (HBPM) is currently recommended. In children, there is considerable evidence on the clinical utility of ABPM, whereas the evidence on HBPM is limited. This systematic review presents (i) the benefits of HBPM in children; (ii) the evidence on normal range, diagnostic accuracy, and relationship with preclinical organ damage; and (iii) guidance for devices, monitoring schedule, and interpretation.

RECENT FINDINGS

HBPM is a useful adjunct to the conventional office measurements for the evaluation of children with suspected or treated hypertension. HBPM is feasible in children and has good reproducibility, diagnostic accuracy and acceptability by users, and relatively low cost. Thus, it has greater potential for widespread and long-term use than ABPM, which is more expensive and often not available or not tolerated. Automated monitors that have been clinically validated specifically in children should be used with appropriate cuff size. HBPM for 7 days (minimum 3) with duplicate morning and evening measurements (minimum 12 readings) should be performed in children with suspected or treated hypertension before each office visit. Until more data become available, in case of diagnostic disagreement between office blood pressure and HBPM, treatment decisions should be based on ABPM. HBPM is clinically useful in children with hypertension. More research is needed on its clinical application, and more automated devices need to be clinically validated in this population.

Risk of cardiovascular involvement in pediatric patients with X-linked hypophosphatemia

OBJECTIVE

To find out if cardiovascular alterations are present in pediatric patients with X-linked hypophosphatemia (XLH).

STUDY DESIGN

Multicentre prospective clinical study on pediatric patients included in the RenalTube database ( www.renaltube.com ) with genetically confirmed diagnosis of XLH by mutations in the PHEX gene. The study's protocol consisted of biochemical work-up, 24-h ambulatory blood pressure monitoring (ABPM), carotid ultrasonography, and echocardiogram. All patients were on chronic treatment with phosphate supplements and 1-hydroxy vitamin D metabolites.

RESULTS

Twenty-four patients (17 females, from 1 to 17 years of age) were studied. Serum concentrations (X ± SD) of phosphate and intact parathyroid hormone were 2.66 ± 0.60 mg/dl and 58.3 ± 26.8 pg/ml, respectively. Serum fibroblast growth factor 23 (FGF23) concentration was 278.18 ± 294.45 pg/ml (normal < 60 pg/ml). Abnormally high carotid intima media thickness was found in one patient, who was obese and hypertensive as revealed by ABPM, which disclosed arterial hypertension in two other patients. Z scores for echocardiographic interventricular septum end diastole and left ventricular posterior wall end diastole were + 0.77 ± 0.77 and + 0.94 ± 0.86, respectively. Left ventricular mass index (LVMI) was 44.93 ± 19.18 g/m^2.7, and four patients, in addition to the obese one, had values greater than 51 g/m^2.7, indicative of left ventricular hypertrophy. There was no correlation between these echocardiographic parameters and serum FGF23 concentrations.

CONCLUSIONS

XLH pediatric patients receiving conventional treatment have echocardiographic measurements of ventricular mass within normal reference values, but above the mean, and 18% have LVMI suggestive of left ventricular hypertrophy without correlation with serum FGF23 concentrations. This might indicate an increased risk of cardiovascular involvement in XLH.

Twenty-four hour ambulatory blood pressure reference values in Africans

OBJECTIVE

We aimed to establish reference values for 24 h ambulatory blood pressure (ABP) monitoring in an African community.

PATIENTS AND METHODS

We randomly recruited 1219 participants of African ancestry from Soweto, a township in Johannesburg. Twenty-four hour ABP was measured using ABP monitors (model 90207; Spacelab). Complete 24 h ABP measurements from 530 healthy participants with a mean age of 38 were used to determine thresholds.

RESULTS

Twenty-four hour, daytime and night-time systolic and diastolic BP increased significantly with age. The 95th prediction bands of this relation at age 38 years were ∼135/85 mmHg for 24 h, 140/90 mmHg for daytime and 130/80 mmHg for night-time ABP values, respectively. These thresholds and absolute ABP values are similar to those observed in individuals of other demographics. These thresholds increase with age by an average of 1.5 mmHg with each decade's increase in age.

CONCLUSION

Pending authentication in prospective outcome-based studies, these values might be considered preliminary thresholds to diagnose hypertension in individuals of African descent.

Treating Hypertension in Children With n-of-1 Trials

OBJECTIVES

Clinicians prescribe antihypertensive medication to children with primary hypertension, but without data to define a particular choice as first-line therapy. A one-size-fits-all approach may not be appropriate for these patients. Our aim was to develop a personalized approach to hypertension treatment, using repeated ambulatory blood pressure monitoring (ABPM) in n-of-1 trials (single-patient randomized crossover trials).

METHODS

Children undergoing hypertension management at a single pediatric referral center were offered participation in an n-of-1 trial with repeated ABPM to compare 3 commonly used medications. The medication producing the greatest blood pressure reduction, and without unacceptable side effects, was selected as the preferred therapy for the individual.

RESULTS

Forty-two children agreed to participate; 7 were normotensive without medication; and 3 failed to complete one treatment cycle. Of the remaining 32 patients, lisinopril was preferred for 16, amlodipine for 8, hydrochlorothiazide for 4, and 4 had uncontrolled blood pressure on maximum doses of monotherapy. In conservative Bayesian analyses, the proportion of patients who preferred lisinopril was 49% (95% credible interval [CrI]: 32% to 69%), 24% (95% CrI: 12% to 41%) preferred amlodipine, and 12% (95% CrI: 4% to 26%) preferred hydrochlorothiazide. The preferred therapy for the majority (67%) of African American participants was lisinopril. Unacceptable side effects were reported in 24% of assessments for hydrochlorothiazide, 16% for lisinopril, and 13% for amlodipine.

CONCLUSIONS

No single medication was preferred for more than half of hypertensive children. n of-1 trials with repeated ABPM may promote better informed and individualized decisions in pediatric hypertension management.

Prevalence and Risk Factors for Arterial Hypertension Development in Childhood Acute Lymphoblastic Leukemia Survivors

BACKGROUND

Childhood acute lymphoblastic leukemia (ALL) survivors are at an increased risk of cardiovascular disease including arterial hypertension (AH). The objectives of this study were to assess the prevalence of AH using 24-hour ambulatory blood pressure monitoring, explore characteristics of AH, and define risk factors for the development of AH in childhood ALL survivors.

PATIENTS AND METHODS

The study comprised 81 childhood ALL survivors (5 to 25 y of age) after a median follow-up time of 5 years. The control group consisted of 52 healthy children (5 to 17 y of age) without any known severe or chronic medical condition. Ambulatory blood pressure monitoring was performed in all patients and controls. Serum lipids were measured in all patients and controls.

RESULTS

ALL survivors were more likely to have AH than controls (odds ratio, 2.47; 95% confidence interval, 1.08-5.63; P=0.0315). The mean time from ALL diagnosis until diagnosis of AH was 5.1±2.97 years. Day-time diastolic SDS and day-time mean arterial pressure SDS were significantly higher in ALL cohort compared with the controls (-0.3±1.43 vs. -0.76±0.95; P=0.04 and 1.44±1.64 vs. 0.92±1.03; P=0.047). Childhood ALL survivors with AH were more likely to be systolic extreme dippers and reverse systolic/diastolic dippers compared with those with normal blood pressure (P<0.05). There was no association of AH with leukemia subtype, leukemia risk group, sex, central nervous system irradiation, and obesity.

CONCLUSIONS

The prevalence of AH in childhood ALL survivors may be as high as 37%. We recommend regular monitoring of blood pressure in childhood ALL survivors early in the follow-up.

Behavior of Blood Pressure Variables in Children and Adolescents with Duchenne Muscular Dystrophy

Background

Duchenne muscular dystrophy is an X-chromosome-linked genetic disorder (locus Xp21). Involvement of the cardiovascular system is characterized by fibrous degeneration/replacement of myocytes with consequent ventricular hypertrophy and arterial hypertension.

Objective

To assess, by using 24-hour ambulatory blood pressure monitoring, the behavior of blood pressure variables in children and adolescents with a confirmed diagnosis of Duchenne muscular dystrophy.

Methods

Prospective observational cohort study, which selected 46 patients followed up on an outpatient basis, divided according to age groups. Blood pressure was classified according to the age percentile. The monitoring interpretation includes systolic and diastolic blood pressure means, systolic and diastolic blood pressure loads, and nocturnal dipping. The blood pressure means were calculated for the 24-hour, wakefulness and sleep periods. Nocturnal dipping was defined as a drop in blood pressure means during sleep greater than 10%. The significance level adopted was p < 0.05.

Results

Nocturnal dipping for systolic blood pressure was present in 29.9% of the participants. Approximately 53% of them had attenuated nocturnal dipping, and 15%, reverse nocturnal dipping. The age groups of 9-11 years and 6-8 years had the greatest percentage of attenuation, 19.1% and 14.9%, respectively. Regarding diastolic blood pressure, nocturnal dipping was identified in 53.2% of the children, being extreme in 27.7% of those in the age group of 6-11 years.

Conclusions

The early diagnosis of blood pressure changes can allow the appropriate and specific therapy, aimed at increasing the life expectancy of patients with Duchenne muscular dystrophy.

Effect of Adenotonsillectomy on Ambulatory Blood Pressure in Pediatric Obstructive Sleep Apnea: 6-Month Follow-up Study

Objective

To investigate 24-hour ambulatory blood pressure changes 6 months after surgery among children with obstructive sleep apnea.

Study Design

Prospective interventional study.

Setting

Tertiary medical hospital.

Subjects and Methods

Children aged 4 to 16 years with symptoms of obstructive sleep apnea (apnea-hypopnea index >1) were recruited. All children underwent adenotonsillectomy and postoperative polysomnography overnight. The 24-hour ambulatory blood pressure was measured before and 6 months after surgery.

Results

The study cohort enrolled 124 children: mean (SD) age, 7.3 (3.1) years; 73% boys. After surgery, the apnea-hypopnea index significantly decreased from 13.3 (18.1) to 3.3 (7.2) events per hour ( P < .001). Overall systolic blood pressure and diastolic blood pressure were not significantly different following surgery, while daytime systolic blood pressure was slightly increased (114.3 to 117.3 mm Hg, P < .01) postoperatively. The hypertensive group (n = 43) exhibited significantly decreased levels of overall diastolic, nighttime systolic, and nighttime diastolic blood pressure ( P < .05), and 54% of hypertensive children became nonhypertensive after surgery. The nonhypertensive group (n = 81) showed slightly increased levels of nocturnal overall systolic, daytime systolic, and nighttime systolic blood pressure. A generalized linear mixed model revealed that children with hypertension had a greater decrease in systolic and diastolic ambulatory blood pressure during the daytime and nighttime (all P < .05) than those without hypertension.

Conclusions

Ambulatory blood pressure changes after adenotonsillectomy among children with obstructive sleep apnea are minimal. The decrease in ambulatory blood pressure after surgery is more prominent for hypertensive children than nonhypertensive children.

Correlates of elevated blood pressure in healthy children: a systematic review

The prevalence of hypertension in children is increasing globally. Addressing this will require a robust understanding of associated risk factors. To this end, we conducted a systematic review to identify correlates of elevated blood pressure (BP) in children. Literature searches were conducted using pre-defined search terms from three academic databases. The abstract and full text of identified studies were screened for eligibility by two independent reviewers. A total of 100 studies were included in this systematic review. An assessment tool was first used to assess study quality; a narrative synthesis was then performed. We found a broad range of physiological, social and behavioural factors associated with elevated BP in children. The most common correlate observed was adiposity, suggesting that childhood obesity may be implicated in the increased prevalence of hypertension observed in children. However, the broad range of other factors identified underscores the multi-factorial aetiology of hypertension. Data from a broad range of studies showed that the correlates of hypertension in children are multi-factorial. Therefore, approaches aimed at preventing hypertension must in turn be multi-factorial to ensure that the burden of hypertension in childhood is addressed.

Epidemiology of Childhood Onset Essential Hypertension

The knowledge of epidemiology of a disease is paramount in identifying preventive measures. Currently there is a paucity of literature on the epidemiologic determinants of childhood onset essential hypertension (EH). We evaluated children with EH, ascertained in a rigorous manner, in a large multiethnic population in a tertiary pediatric hypertension clinic. We enrolled children with and without EH and obtained data by in-person interview of their parents and by direct anthropometric measurements including blood pressures. A total of 148 children (76 hypertension probands, 72 control probands, and males 53%, mean age 12.2 ± 4.3 years) were enrolled. Of these 148 children, 51 pairs were matched 1:1 on ethnicity, gender and age (± 2.5 years). In this study we evaluated the demographics, genetic predisposition and a variety of exposures including, socioeconomic, perinatal, lifestyle and environmental, between cases and controls. All measures were similar between cases and controls other than a significantly higher BMI (p = 0.01) and rates of obesity (p = 0.03), and a difference of near-significance in any family history of EH (p = 0.05) higher in cases compared to controls. The odds of obesity was 3.5 times higher among cases than controls. In this study we evaluated a variety of prenatal and postnatal exposures that could potentially contributed to the EH phenotype in childhood. The findings of the study elucidate the epidemiology of EH in children and two important associated risk factors, any family history of hypertension and a higher body weight.

Endothelin-1, nitric oxide, serotonin and high blood pressure in male adolescents

Background

Essential arterial hypertension (EAH) in adolescents represents a social burden. The endothelium is involved in the pathogenesis of EAH. Imbalance of key vasoactive factors – namely nitric oxide (NO) and endothelin-1 (ET-1) – is observed, and serotonin (5-HT) release is also impaired. The relationship between the factors and high blood pressure (BP) has been established mainly in preclinical studies and in the adult age. The aim of the present manuscript is to establish the association between plasma ET-1, serum NO and 5-HT, platelet 5-HT levels and BP in male adolescents, analyzing their concentrations in controls, prehypertensive and hypertensive children. Consequently, we want to evaluate ET-1, NO and 5-HT levels as preclinical biomarkers of EAH.

Methods

Outpatient adolescents, examined at Children’s Republican Clinical Hospital of the Ministry of Health of the Republic of Tatarstan, were recruited between 26th of May and 25th of September 2016. Predictor variables identified were plasma ET-1, serum NO and 5-HT levels and were evaluated in serum and platelets of case and control groups.

Results

Plasma ET-1 and serum 5-HT concentrations in prehypertensive and hypertensive children were higher than in controls, with hypertensive adolescents showing higher levels of both factors compared with prehypertensive adolescents. Platelet 5-HT levels were lower in prehypertensive and hypertensive children compared with controls, while serum NO levels were higher in prehypertensive children than in hypertensive children.

Conclusion

Measurable ET-1, NO and 5-HT are related to BP in adolescents and may serve as diagnostic biomarkers of EAH. Furthermore, they could help to better define prehypertensive and hypertensive children.

Does the type of sedentary behaviors influence blood pressurein adolescents boys and girls? A cross-sectional study

Abstract The aim of this study was to analyze the association between different sedentary behaviors and high blood pressure in adolescent boys and girls. We conducted a cross-sectional study with 6,264 Brazilian adolescents (14 to 19 years old). Demographic data, obesity indicators and blood pressure, were evaluated. Time spent in the sedentary behaviors (television viewing, playing video games, using the computer, non-screen sitting and, total time sitting) were also assessed. The girls spent more time watching television than boys, whereas boys spent more time using computers and video games (12.7% vs. 7.4%, p < 0.001) than girls. Boys who watched more than four hours of television presented higher odds to give high blood pressure after adjustments for physical activity level, body mass index, age and educational level of mother (OR = 2.27, p < 0.001). In girls, we did not find a relation between sedentary behaviors and high blood pressure (p > 0.05). Television viewing time is associated with high blood pressure only boys. So, reduce this sedentary behavior, stimulating physical activities, might be essential to health, principally for male adolescents.

24-Hour Ambulatory Blood Pressure after Adenotonsillectomy in Childhood Sleep Apnea

OBJECTIVE

To assess the effects of adenotonsillectomy (T&A) on ambulatory blood pressure (ABP) in childhood obstructive sleep apnea (OSA).

STUDY DESIGN

From 2012 to 2017, children aged 4-16 years with symptoms and polysomnography-diagnosed OSA (apnea-hypopnea index [AHI] >1) underwent T&A. PSG studies and 24-hour ABP monitoring were performed before and at 3 months after surgery.

RESULTS

In total, 159 children were enrolled (mean age, 7.8 ± 3.3 years; 72% male). T&A significantly reduced the AHI from 12.4 ± 15.9 events/hour to 2.7 ± 5.7 events/hour (P < .001). A decrease was observed in the children's overall diastolic blood pressure (65.1 ± 6.1 mm Hg to 63.8 ± 7.4 mm Hg, P = .04) after surgery. In subgroup analysis, 100 (63%) patients were classified as nonhypertensive, and 59 (37%) were classified as hypertensive. Linear mixed model analysis revealed that compared with the children without hypertension, those with hypertension had superior improvement in systolic and diastolic blood pressure during daytime and nighttime (all P values < .01). The ABP changes after surgery were not correlated with the AHI changes. Finally, preoperative hypertension was an independent risk factor of postoperative hypertension among these children (OR 3.66; 95% CI 1.70-7.86).

CONCLUSIONS

Overall, in children with OSA, the 24-hour ABP change after T&A is small. However, among children with preoperative hypertension, there is significant BP improvement after T&A surgery.

Prevalence of Hypertension in Children with Early-Stage ADPKD

BACKGROUND AND OBJECTIVES

Autosomal dominant polycystic kidney disease is the most common inheritable kidney disease, frequently thought to become symptomatic in adulthood. However, patients with autosomal dominant polycystic kidney disease may develop signs or symptoms during childhood, in particular hypertension. Although ambulatory BP monitoring is the preferred method to diagnose hypertension in pediatrics, data in children with autosomal dominant polycystic kidney disease are limited.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Our retrospective multicenter study was conducted to collect ambulatory BP monitoring recordings from patients with autosomal dominant polycystic kidney disease age <18 years old. Basic anthropometric parameters as well as data on kidney function, BP treatment, and kidney ultrasound were also collected.

RESULTS

Data from 310 children with autosomal dominant polycystic kidney disease with a mean age of 11.5±4.1 years old were collected at 22 European centers. At the time when ambulatory BP monitoring was performed, 95% of children had normal kidney function. Reference data for ambulatory BP monitoring were available for 292 patients. The prevalence rates of children with hypertension and/or those who were treated with antihypertensive drugs were 31%, 42%, and 35% during daytime, nighttime, or the entire 24-hour cycle, respectively. In addition, 52% of participants lacked a physiologic nocturnal BP dipping, and 18% had isolated nocturnal hypertension. Logistic regression analysis showed a significant association between a categorical cyst score that was calculated on the basis of the number of cysts >1 cm per kidney and daytime hypertension (odds ratio, 1.70; 95% confidence interval, 1.21 to 2.4; P=0.002), nighttime hypertension (odds ratio, 1.31; 95% confidence interval, 1.05 to 1.63; P=0.02), or 24-hour hypertension (odds ratio, 1.39; 95% confidence interval, 1.08 to 1.81; P=0.01). Kidney length, expressed as SD score, was also significantly associated with nighttime hypertension (odds ratio, 1.23; 95% confidence interval, 1.06 to 1.42; P=0.10).

CONCLUSIONS

These data indicate high prevalence of hypertension in children with autosomal dominant polycystic kidney disease starting at young ages.

Importance of ambulatory blood pressure monitoring in the diagnosis and prognosis of pediatric hypertension

The prevalence of high blood pressure (BP) at pediatric age has increased progressively, one of the causes of which is obesity. However, the dominant etiology in this age group is renal and/or cardiovascular pathology. Ambulatory blood pressure monitoring (ABPM) is the method of choice for the diagnosis of hypertension, especially in children at high cardiovascular risk. Its use is limited to children from five years of age. Choosing appropriate cuff size is key to obtaining correct blood pressure. The main indication for ABPM is to confirm the diagnosis of hypertension. It also allows the diagnosis of white coat hypertension (which may represent an intermediate stage between the normotensive phase and hypertension), or masked hypertension, associated with progression to sustained hypertension and left ventricular hypertrophy (LVH). Children with isolated nocturnal hypertension should be considered as having masked hypertension. BP load is defined as the percentage of valid measurements above the 95th percentile for age, gender, and height. Values above 25-30% are pathological and those above 50% are predictive of LVH. ABPM correlates with target organ damage, particularly LVH and renal damage. It is useful in the differentiation of secondary hypertension, since these children show higher BP load and less nocturnal dipping, and confirmation of response to therapy. Thus ABPM allows the diagnosis and classification of hypertension, provides cardiovascular prognostic information and identifies patients with intermediate phenotypes of hypertension.

Office blood pressure measurement alone often misclassifies treatment status in children with primary hypertension

OBJECTIVE

Clinicians frequently rely on office blood pressure (BP) measurements alone to assess hypertension control, despite widespread acceptance of 24-h ambulatory blood pressure monitoring (ABPM) as the reference standard in the initial diagnosis of hypertension. This study was designed to investigate how often the hypertensive status differed between concurrent office BP versus ABPM measurements, and whether any patient-specific characteristics predict the risk for misclassification by office BP.

PARTICIPANTS AND METHODS

This study evaluated 42 children with primary hypertension who underwent repeated ambulatory monitoring (190 total recordings) with concurrent office BP measurement as part of their participation in n-of-1 trials.

RESULTS

In nearly 40% of the visits, the treatment status by office measurement was opposite to the status by ambulatory monitoring. Office BP underestimated the ambulatory hypertensive status (masked uncontrolled hypertension) in 25% of visits and overestimated ambulatory BP (white coat effect) in 14% of visits. The difference between office BP and ambulatory monitoring was consistent within patients across repeated visits. Patients whose office measurement underestimated or overestimated the ambulatory BP at the first visit were more likely to show persistent discrepancy at subsequent visits.

CONCLUSION

The underuse of ambulatory monitoring in management decisions of children treated for primary hypertension may result in systematic misclassification of hypertension control.

Ambulatory hypertension in a pediatric cohort of sickle cell disease

Hypertension is an established risk factor for subsequent cardiovascular and renal disease in children as well as adults. Sickle cell disease (SCD) is a genetic disorder associated with chronic hemolytic anemia with the major manifestation of vaso-occlusive crises. Although this disease entity involves most organ systems causing vascular and pulmonary injury, little is known about blood pressure (BP) levels or prevalence of hypertension in children with SCD. A cross-sectional study was conducted on 56 children with SCD (54 with hemoglobin SS disease; 2 with hemoglobin Sβ⁰ thalassemia; 29 females). Study participants underwent 24-hour ambulatory BP monitoring (ABPM). Serum creatinine and cystatin C were obtained to assess estimated glomerular filtration rate with age-based formulas. A random urine sample was obtained to estimate urine osmolality and urine albumin to creatinine ratio. Mean age range was 11.9 (±4.5) years. Seventeen participants (30%) met criteria for hypertension based on ABPM. Of the 17 participants classified with hypertension, three had office hypertension with ambulatory hypertension, and 14 had masked hypertension detected on ABPM. Another 28 participants (50%) had some abnormal ABPM parameters in the form of either prehypertension and/or lack of normal nocturnal dipping status. The prevalence of confirmed hypertension, largely manifest by masked hypertension, is high in children, as young as 6 years of age with SCD. Early identification of hypertension in SCD children can confer benefit as it is an important modifiable risk factor for progression of cardiovascular and renal disease.

Sex differences in fitness outcomes among minority youth after participation in a park-based after-school program

PURPOSE

This study aimed to describe sex differences in fitness outcomes after participation in Fit2Play, a park-based after-school health and wellness program.

METHODS

Youth who participated in Fit2Play for either 1, 2, or 3 school years between 2010 and 2016 (n = 2129, mean age 9.1 years, 52% Hispanic, 48% non-Hispanic black, 54% male) were tested via a comprehensive fitness battery at the beginning/end of the school year(s). Effects of length of Fit2Play participation on fitness outcomes were assessed via three-level repeated measures analysis stratified by sex and adjusted for child sociodemographics, weight category, area poverty, and year.

RESULTS

Significant improvements for boys and girls were found in the Progressive Aerobic Cardiovascular Endurance Run (P < .01 for girls, P < .001 for boys), 400 meter run tests (P < .001 for girls, P < .01 for boys), and push-ups (P < .01 for both), with dose-response trends for girls after up to 3 years of Fit2Play participation. From baseline to 1, 2, and 3 years of participation, girls demonstrated 8%, 14%, and 23% mean improvement in 400 meter run times versus 9%, 9%, and 17% for boys, respectively (P < .001 for all). Dose-response improvements were also found in girls for PACER scores and sit-ups.

CONCLUSIONS

After-school physical activity programs can improve fitness in all youth, and particularly girls with increased years of participation. Further research should examine sex differences in the effects of park-/community-based programs to reduce sex disparities in fitness, particularly in light of the current youth obesity epidemic.

Familial aggregation of first degree relatives of children with essential hypertension

PURPOSE

Determining familial aggregation is an important first step in narrowing the search for disease-causing genes and hence we determined the familial aggregation of EH among first degree relatives of children with EH.

MATERIALS AND METHODS

We prospectively enrolled children with EH along with their first degree relatives from a tertiary pediatric hypertension clinic in a large ambulatory care center. We utilized rigorous methodology for blood pressure (BP) measurements and diagnoses of EH to reduce the heterogeneity in the phenotype. For those enrolled, parental BP status was confirmed by in-clinic direct BP measurements. We also enrolled control children without EH along with their first degree relatives from the same pediatric ambulatory center.

RESULTS

In our case-control study of 153 families, the odds of having familial EH was more than 3 times higher among the cases than in controls (OR: 3.63, 95% CI: 1.85-7.12) with 71% of the cases and 41% of the controls reporting familial EH. One parent with EH was seen in 88% of the cases and 52% of the controls (OR: 6.92, 95% CI: 2.68-17.84). The odds of at least one parent (compared to neither) with EH was almost 7-fold higher, and odds of having two parents with EH was 14-fold higher among cases versus controls. The risk of EH did not go back from the first degree relative to the second degree relatives.

CONCLUSIONS

We identified familial aggregation with an increased liability of childhood onset EH with parental EH. The risk of childhood onset EH is more than doubled in the presence of EH in both parents versus in a single parent. Prediction for childhood-onset EH is improved by obtaining a family history of EH in the first degree relatives.

Comparison of ambulatory blood pressure monitoring and office blood pressure measurements in obese children and adolescents

BACKGROUND

Obesity in adults has been related to hypertension and abnormal nocturnal dipping of blood pressure, which are associated with poor cardiovascular and renal outcomes. Here, we aimed to resolve the relationship between the degree of obesity, the severity of hypertension and dipping status on ambulatory blood pressure in obese children.

METHODS

A total 72 patients with primary obesity aged 7 to 18 years (mean: 13.48 ± 3.25) were selected. Patients were divided into three groups based on body mass index (BMİ) Z-score. Diagnosis and staging of ambulatory hypertension based on 24-h blood pressure measurements, obtained from ambulatory blood pressure monitoring.

RESULTS

Based on our ambulatory blood pressure data, 35 patients (48.6%) had hypertension, 7 (20%) had ambulatory prehypertension, 21 (60%) had hypertension, and 7 patients (20%) had severe ambulatory hypertension. There was a significant relationship between severity of hypertension and the degree of obesity (p < 0.05). Thirty-one patients (88.6%) had isolated nighttime hypertension, and 53 patients (73.6%) were non-dippers. All systolic blood pressure results and loads were similar between groups. Diastolic and mean arterial blood pressure levels during the night, diastolic blood pressure loads, and heart rate during the day were significantly higher in Group 3 (p < 0.05). Nocturnal non-dipping was not associated with severity of obesity.

CONCLUSION

Obesity was associated with severity of hypertension, higher diastolic blood pressure at night, mean arterial pressure at night, diastolic blood pressure loads and heart rate at day. Increase in BMI Z-score does not a significant impact on daytime blood pressure and nocturnal dipping status.

Determinants of Increased Aortic Diameters in Young Normotensive Patients With Turner Syndrome Without Structural Heart Disease

Factors associated with aortic dilation and dissection in patients with Turner syndrome (TS) remain unclear. We assessed magnetic resonance imaging-based aortic diameters at nine predefined anatomic positions and examined associations of increased aortic diameters with B-type natriuretic peptide (BNP), A-type NP (ANP), growth hormone treatment, insulin-like growth factor 1 (IGF1), and estrogen status. Forty-seven patients with TS aged 7.3-21 years and 34 healthy peers were enrolled in this study. Aortic diameters were higher in patients with TS at three positions than in controls (p < 0.05). History of GH treatment, pubertal status, and serum estradiol levels were not associated with increased aortic diameters. Patients with TS had higher plasma BNP and ANP levels than controls. BNP and IGF1 were independently associated with the increase in aortic diameters in TS at three positions of the ascending aorta (R² = 0.361-0.458, p < 0.05 for all). At two positions of the descending aorta, only BNP emerged as an independent variable (R² = 0.130-0.139, p < 0.05). We conclude that young, normotensive patients with TS had greater aortic diameters at several positions than healthy controls. BNP and IGF1 were independently associated with increased aortic diameters in TS.

Whole blood viscosity and cerebral blood flow velocities in obese hypertensive or obese normotensive adolescents

BACKGROUND

Obesity affects all major organ systems and leads to increased morbidity and mortality. Whole blood viscosity is an important independent regulator of cerebral blood flow. The aim of the present study was to evaluate the effect of whole blood viscosity on cerebral artery blood flow velocities using transcranial Doppler ultrasound in pediatric patients with obesity compared to healthy controls and analyze the effect of whole blood viscosity and blood pressure status to the cerebral artery blood flow velocities.

METHODS

Sixty patients with obesity diagnosed according to their body mass index (BMI) percentiles aged 13-18 years old were prospectively enrolled. They were grouped as hypertensive or normotensive according to their ambulatory blood pressure monitoring. Whole blood viscosity and middle cerebral artery velocities by transcranial Doppler ultrasound were studied and compared to 20 healthy same aged controls.

RESULTS

Whole blood viscosity values in hypertensive (0.0619±0.0077 poise) and normotensive (0.0607±0.0071 poise) groups were higher than controls (0.0616±0.0064 poise), with no significance. Middle cerebral artery blood flow velocities were higher in the obese hypertensive (73.9±15.0 cm/s) and obese normotensive groups (75.2±13.5 cm/s) than controls (66.4±11.5 cm/s), but with no statistical significance.

CONCLUSIONS

Physiological changes in blood viscosity and changes in blood pressure did not seem to have any direct effect on cerebral blood flow velocities, the reason might be that the cerebral circulation is capable of adaptively modulating itself to changes to maintain a uniform cerebral blood flow.

Impact of change in neighborhood racial/ethnic segregation on cardiovascular health in minority youth attending a park-based afterschool program

Research on the mechanistic factors associating racial/ethnic residential segregation with health is needed to identify effective points of intervention to ultimately reduce health disparities in youth. We examined the association of changes in racial/ethnic segregation and cardiovascular health outcomes including body mass index percentile, sum of skinfold thicknesses, systolic and diastolic blood pressure percentile, and 400 m run time in non-Hispanic Black (NHB) and Hispanic youth (n = 2,250, mean age 9.1 years, 54% male; 51% Hispanic, 49% NHB; 49% high area poverty; 25% obese) attending Fit2Play™, a multisite park-based afterschool program in Miami, Florida, USA. A series of crude and adjusted two-level longitudinal generalized linear mixed models with random intercepts for park effects were fit to assess the association of change in segregation between home and program/park site and cardiovascular health outcomes for youth who participated for up to two school years in Fit2Play™. After adjusting for individual-level factors (sex, age, time, and park-area poverty) models showed significantly greater improvements in cardiovascular health if youth attended Fit2Play™ in an area less segregated than their home area (p < 0.05 for all outcomes) except 400 m run time and diastolic blood pressure percentile in Hispanics (p<.001 and p = 0.11, respectively). Area poverty was not found to confound or significantly modify this association. These findings have implications for youth programming focused on reducing health disparities and improving cardiovascular outcomes in NHB and Hispanic youth, particularly in light of a continually expanding obesity epidemic in these groups. Parks and Recreation Departments have potential to expand geographic mobility for minorities, therein supporting the national effort to reduce health inequalities.

Twenty-Four-Hour Ambulatory Blood Pressure versus Clinic Blood Pressure Measurements and Risk of Adverse Outcomes in Children with CKD

BACKGROUND

and objectives Our objective was to determine whether clinic BPs (taken at either a single visit or two sequential visits) are inferior to ambulatory BPs in their ability to discriminate risk of adverse outcomes in children with CKD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We included 513 participants of the CKD in Children Study who had clinic BPs and 24-hour ambulatory BP monitoring performed during similar timeframes. Predictors of interest were systolic BPs taken at a single visit or two repeated visits within a 1-year period compared with mean wake and sleep systolic ambulatory BPs. Outcomes were left ventricular hypertrophy and ESKD. We determined the ability for each BP parameter to provide risk discrimination using c statistics.

RESULTS

During mean follow-up of 3.5 years, 123 participants developed ESKD. In cross-sectional unadjusted analysis, every 0.1 increase in systolic BP index was associated with a 2.0 times higher odds of left ventricular hypertrophy (95% confidence interval, 1.5 to 2.8) by clinic BPs versus 1.8 times higher odds (95% confidence interval, 1.3 to 2.4) by ambulatory wake BP. The c statistic was highest for clinic BP (c=0.65; 95% confidence interval, 0.58 to 0.73) but similar to ambulatory wake BP (c=0.64; 95% confidence interval, 0.57 to 0.71) for the discrimination of left ventricular hypertrophy. In longitudinal unadjusted analysis, every 0.1 increase in systolic BP index was associated with a higher risk of ESKD using repeated clinic (hazard ratio, 1.5; 95% confidence interval, 1.3 to 1.8) versus ambulatory wake BP (hazard ratio, 1.6; 95% confidence interval, 1.3 to 2.0). Unadjusted c statistics were the same for wake (c=0.61; 95% confidence interval, 0.56 to 0.67) and clinic systolic BPs (c=0.61; 95% confidence interval, 0.55 to 0.66) for discriminating risk of ESKD.

CONCLUSIONS

Clinic BPs taken in a protocol-driven setting are not consistently inferior to ambulatory BP in the discrimination of BP-related adverse outcomes in children with CKD.

Blood pressure in children with attention deficit/hyperactivity disorder

Objectives

Children with attention deficit/hyperactivity disorder (ADHD) are frequently treated with psycho-stimulant agents causing a modest but significant increase in blood pressure and heart rate. The objective of this study was to define blood pressure characteristics in children with ADHD treated with a variety of medications in a community setup.

Methods

Children registered at a large paediatric clinic in Calgary, AB with documented histories of ADHD were randomly contacted. Consenting participants had standardized office BP measurements, ambulatory blood pressure monitoring (ABPM) studies and were asked to complete the sleep disturbance scale for children (SDSC) questionnaire. Findings were compared with data from the Canadian Health Measures Survey (CMHS).

Results

Fifty-five children (47 males) aged 7 to 17 years (average 11.6 ± 2.5 years) with an average BMI z-score of -0.37 ± 1.22 completed the study. All children were medicated, the majority (82%), with various types of stimulant agents. Elevated office BP values were more prevalent than in the CMHS; >90th percentile in 5 (9.1%) and >95th percentile in 3 (5.5%). ABPM confirmed 'white coat hypertension' in 3 (5.5%), masked hypertension in 2 (3.6%) and nondipping in 28 (51%). The SDSC score suggested that 43 (78%) children had disturbed sleep. Logistic regression modelling indicated that nondipping correlated with disturbed sleep.

Conclusion

The 'white coat' phenomenon may be responsible for increased prevalence of elevated rest/office BP values in children with ADHD. Prevalent sleep 'non-dipping' in this population is associated with sleep disturbances but clinical significance of this finding requires further investigation.

Blood pressure variability is independent of systolic pressure in adolescent and young adult patients undergoing hemodialysis

BackgroundPre-dialysis blood pressure variability (BPV) in adolescent and young-adult maintenance hemodialysis (MHD) patients remains unknown. This study aimed to show the degree of 44-h BPV and to explore its related risk factors in adolescent and young-adult MHD patients.MethodsOne hundred and fifty-three hemodialysis patients aged from 14 to 29 were selected from 11 medical facilities in Guizhou, China. Variability independent of the mean BP (VIM) obtained by 44-h ambulatory BP monitoring was used to calculate BPV. Baseline characteristics, physical measurement, and laboratory parameters were compared between different groups categorized by quartiles of VIM of systolic BP (VIMSBP).ResultsVIMSBP levels were found to be positively related to interdialytic weigh growth rate (IDWG), serum phosphorus, and serum intact parathyroid hormone (iPTH; Spearman correlation coefficients 0.474, 0.229, and 0.437, respectively; P<0.05 for all) and negatively related to hemoglobin (Hb) and albumin (-0.317, P<0.001, and -0.166, P=0.04, respectively) in all adolescent and young-adult MHD patients. In multiple linear regression analysis, IDWG, Hb, serum phosphorus, and serum iPTH had an independent association with VIMSBP.ConclusionOur analysis revealed an independent association of BPV with IDWG, Hb, serum phosphorus, and serum iPTH among adolescent and young-adult patients undergoing dialysis. This observation warrants further study.