The impact of the degree of obesity on the discrepancies between office and ambulatory blood pressure values in youth

Masked Hypertension in Healthy Children and Adolescents: Who Should Be Screened?

PURPOSE OF REVIEW

The goal is to review masked hypertension (MH) as a relatively new phenomenon when patients have normal office BP but elevated out-of-office BP. Firstly, it was described in children in 2004. It has received increased attention in the past decade.

RECENT FINDINGS

The prevalence of MH in different pediatric populations differs widely between 0 and 60% based on the population studied, definition of MH, or method of out-of-office BP measurement. The highest prevalence of MH has been demonstrated in children with chronic kidney disease (CKD), obesity, diabetes, and after heart transplantation. In healthy children but with risk factors for hypertension such as prematurity, overweight/obesity, diabetes, chronic kidney disease, or positive family history of hypertension, the prevalence of MH is 9%. In healthy children without risk factors for hypertension, the prevalence of MH is very low ranging 0-3%. In healthy children, only patients with the following clinical conditions should be screened for MH: high-normal/elevated office BP, positive family history of hypertension, and those referred for suspected hypertension who have normal office BP in the secondary/tertiary center.

Cardiovascular variability, sociodemographics, and biomarkers of disease: the MIDUS study

Introduction: Like heart rate, blood pressure (BP) is not steady but varies over intervals as long as months to as short as consecutive cardiac cycles. This blood pressure variability (BPV) consists of regularly occurring oscillations as well as less well-organized changes and typically is computed as the standard deviation of multiple clinic visit-to-visit (VVV-BP) measures or from 24-h ambulatory BP recordings (ABPV). BP also varies on a beat-to-beat basis, quantified by methods that parse variation into discrete bins, e.g., low frequency (0.04-0.15 Hz, LF). However, beat-to-beat BPV requires continuous recordings that are not easily acquired. As a result, we know little about the relationship between LF-BPV and basic sociodemographic characteristics such as age, sex, and race and clinical conditions. Methods: We computed LF-BPV during an 11-min resting period in 2,118 participants in the Midlife in the US (MIDUS) study. Results: LF-BPV was negatively associated with age, greater in men than women, and unrelated to race or socioeconomic status. It was greater in participants with hypertension but unrelated to hyperlipidemia, hypertriglyceridemia, diabetes, elevated CRP, or obesity. LF-diastolic BPV (DBPV), but not-systolic BPV (SBPV), was negatively correlated with IL-6 and s-ICAM and positively correlated with urinary epinephrine and cortisol. Finally, LF-DBPV was negatively associated with mortality, an effect was rendered nonsignificant by adjustment by age but not other sociodemographic characteristics. Discussion: These findings, the first from a large, national sample, suggest that LF-BPV differs significantly from VVV-BP and ABPV. Confirming its relationship to sociodemographic risk factors and clinical outcomes requires further study with large and representative samples.

Office blood pressure versus ambulatory blood pressure measurement in childhood obesity

BACKGROUND

The prevalence of obesity-related co-morbidities is rising parallel to the childhood obesity epidemic. High blood pressure (BP), as one of these co-morbidities, is detected nowadays at increasingly younger ages. The diagnosis of elevated BP and hypertension, especially in the childhood population, presents a challenge to clinicians. The added value of ambulatory blood pressure measurement (ABPM) in relation to office blood pressure (OBP) measurements in obese children is unclear. Furthermore, it is unknown how many overweight and obese children have an abnormal ABPM pattern. In this study we evaluated ABPM patterns in a population of overweight and obese children and adolescents, and compared these patterns with regular OBP measurements.

METHODS

In this cross-sectional study in overweight or obese children and adolescents aged 4-17 years who were referred to secondary pediatric obesity care in a large general hospital in The Netherlands, OBP was measured during a regular outpatient clinic visit. Additionally, all participants underwent a 24-hour ABPM on a regular week-day. Outcome measures were OBP, mean ambulatory SBP and DBP, BP load (percentage of readings above the ambulatory 95th blood pressure percentiles), ambulatory BP pattern (normal BP, white-coat hypertension, elevated BP, masked hypertension, ambulatory hypertension), and BP dipping.

RESULTS

We included 82 children aged 4-17 years. They had a mean BMI Z-score of 3.3 (standard deviation 0.6). Using ABPM, 54.9% of the children were normotensive (95% confidence interval 44.1-65.2), 26.8% had elevated BP, 9.8% ambulatory hypertension, 3.7% masked hypertension, and 4.9% white-coat hypertension. An isolated night-time BP load > 25% was detected in almost a quarter of the children. 40% of the participants lacked physiologic nocturnal systolic BP dipping. In the group of children with normal OBP, 22.2% turned out to have either elevated BP or masked hypertension on ABPM.

CONCLUSIONS

In this study a high prevalence of abnormal ABPM patterns in overweight or obese children and adolescents was detected. Additionally, OBP poorly correlated with the child's actual ABPM pattern. Herewith, we emphasized the usefulness of ABPM as an important diagnostic tool in this population.

Does the Body Mass Index Category Influence Ambulatory Blood Pressure Parameters in Office Normotensive Obese Children?

The aim of our study was to investigate the influence of the degree of obesity on ambulatory blood pressure parameters in selected group of office normotensive obese children and adolescents. Our study involved 119 obese patients (55 males, 46.2%) aged 7-18 years divided into 3 groups based on their body mass index Z-score, who underwent ambulatory blood pressure monitoring. Our results show that obese patients, even when office normotensive, have alterations in blood pressure values obtained by ambulatory blood pressure monitoring. We found a positive correlation between systolic and diastolic blood pressure and body mass index in our patients (p [Formula: see text] 0.001). Daytime blood pressure load correlated with rising body mass index and was higher in groups II and III compared to group I (p < 0.001). Body mass index category did not influence the dipping pattern in our subjects although most of our subjects (66.4%) showed non-dipping pattern for systolic blood pressure. The difference in blood pressure variability was confirmed only for daytime systolic and diastolic values between groups I and II (p = 0.019 and p = 0.002, respectively). In conclusion, our study showed that in office normotensive obese children and adolescents, systolic and diastolic blood pressure values obtained by ambulatory blood pressure monitoring are higher in subjects with higher body mass index. Patients with increased body mass index also have higher percentage of blood pressure readings above 95^th percentile and increased daytime blood pressure variability. Obese patients show non-dipping pattern, independently of the rising body mass index category.

Epidemiology of obesity and high blood pressure among school-age children from military families: the largest report from our region

BACKGROUND

For the first time, we aimed to determine the epidemiology and associated factors of obesity and hypertension among children of military families in our region.

METHODS

In this multi-centered study, children between the ages of 5 to 12 years old, entered the study. Data on baseline and clinical characteristics, history of disease and anthropometric measurements, were collected.

RESULTS

Among 504 children, 44.2% were males. Mean (SD) age of participants was 7.9 ± 1.9 years. Overall, 5% were obese and 9.9% were overweight. In total, 16.3% had elevated BP, 12.5% had stage one and 0.2% had stage two hypertension. Age (beta = 0.306, OR = 1.35, 95% CI:1.14-1.61), obesity/overweight (OR = 5.58, 95% CI:2.59-12.0), history of hypertension in mother (OR = 43.24, 95% CI:5.99-312.11), low birth weight (OR = 7.96, 95% CI:2.59-12.0), physical activity (OR = 0.27, 95% CI:0.10-0.72), and consumption of fast food more than once a week (OR = 3.36, 95% CI:1.82-6.19), were associated with risk of hypertension. Furthermore, age (beta = 0.346, OR = 1.41, 95% CI:1.21-1.64), history of childhood obesity in the father (OR = 3.78, 95% CI: 1.77-8.06) and mother (OR = 2.44, 95% CI:1.07-5.56), and physical activity (OR = 0.27, 95% CI:0.11-0.66), were associated with obesity.

CONCLUSION

Age, obesity/overweight, history of hypertension in the mother, birth weight, physical activity, and consumption of fast food, were associated with risk of hypertension. Moreover, age, history of childhood obesity in parents, and physical activity, were associated with obesity. Furthermore, we found that school-age children in military families have higher rates of hypertension and overweight compared to other reports from our region.

Screening for metabolic complications of childhood and adolescent obesity: A scoping review of national and international guidelines

The rise in prevalence of childhood obesity is paralleled by an increase in obesity-related metabolic complications, which add significantly to the population burden of cardiovascular morbidity in the long term. Early detection of obesity-related metabolic complications through appropriate screening strategies forms a crucial aspect of obesity management. We performed a scoping review of international and national guidelines on the management of pediatric obesity to evaluate the recommendations on screening for metabolic complications, namely, hypertension, diabetes, dyslipidemia, and non-alcoholic fatty liver disease. Thirty guidelines were included, 23 (76.7%) of which had some guidance on screening for metabolic complications. However, there were significant variations in the extent and details of recommendations for screening for these metabolic complications. There has been no consensus on the body mass index (BMI) thresholds, age of onset, frequency, and screening tests recommended for detecting hypertension, diabetes, dyslipidemia, and non-alcoholic fatty liver disease between guidelines. These variations did not appear to be polarized based on geographical location or population ethnicity. We provide our recommendations on metabolic screening based on the strength of evidence in the guidelines, also incorporating recommendations from key childhood hypertension, diabetes, and lipid guidelines. Appropriate implementation of screening strategies is crucial to improve detection of metabolic complications, to allow for earlier or more intensified interventions for affected children with obesity.

Elevated Blood Pressure in Hospitalized Children Predicts True Elevated Blood Pressure Outpatient

OBJECTIVES

To determine if elevated blood pressure (EBP) in hospitalized children accurately predicts EBP outpatient.

METHODS

A multicenter retrospective chart review was conducted at a large hospital system in Northeastern United States. Mean blood pressures during hospitalizations were classified as elevated or not elevated, by using the American Academy of Pediatrics (AAP) 2017 parameters. Mean blood pressure was then compared with each patient's mean blood pressure measured 3 times postdischarge. The data were analyzed to determine if inpatient EBP is an accurate predictor of outpatient EBP.

RESULTS

Of 5367 hospitalized children, 656 (12.2%) had EBP inpatient. Inpatient EBP was highly predictive of outpatient EBP, with a positive predictive value of 96% and negative predictive value of 98%.

CONCLUSIONS

Diagnosing hospitalized children with EBP, as defined by the AAP 2017 guidelines, accurately predicts true EBP outpatient.

Masked hypertension and correlation between body composition and nighttime blood pressure parameters in children and adolescents with obesity

INTRODUCTION

Masked hypertension is defined as having a normal blood pressure (BP) in the office but elevated BP outside the office. This study aimed to determine the prevalence of masked hypertension in participants with obesity and to examine the correlation between body composition, dietary intake and ambulatory blood pressure parameters.

MATERIALS AND METHODS

The cross-sectional study of participants with obesity was conducted in the pediatric nutrition clinic of a University Hospital in Thailand. Demographic and anthropometric data, dietary intake, body composition analysis and ambulatory blood pressure monitoring were assessed in all participants. All parameters were compared between the group with masked hypertension and the normotensive group. Correlations between the parameters were analyzed.

RESULTS

Among 49 children with obesity, 23 (47%, 95% confidence interval 34.7, 59.2%) had masked hypertension. Compared with the normotensive group, the group with masked hypertension had a greater mean BMI z-score (4.7 vs. 3.0, P = 0.003), a greater mean of body fat percentage (45 vs. 40, P = 0.012) and a greater total energy intake percentage of dietary reference intake (115 vs. 93, P = 0.034). Multivariate analysis showed that BMI z-score was significantly associated with masked hypertension. Interestingly, mean nighttime SBP positively correlated with BMI z-score and body fat percentage. Moreover, there were negative correlations between fruit intake portion per week and nighttime and 24-h SBP index. However, multivariate linear regression did not show significant correlation between these parameters.

CONCLUSIONS

Masked hypertension was frequent in participants with obesity. The greater BMI z-score and percentage of body fat mass correlated with higher nighttime SBP.

Home blood pressure monitoring: methodology, clinical relevance and practical application: a 2021 position paper by the Working Group on Blood Pressure Monitoring and Cardiovascular Variability of the European Society of Hypertension

The present paper provides an update of previous recommendations on Home Blood Pressure Monitoring from the European Society of Hypertension (ESH) Working Group on Blood Pressure Monitoring and Cardiovascular Variability sequentially published in years 2000, 2008 and 2010. This update has taken into account new evidence in this field, including a recent statement by the American Heart association, as well as technological developments, which have occurred over the past 20 years. The present document has been developed by the same ESH Working Group with inputs from an international team of experts, and has been endorsed by the ESH.

Can we use copeptin as a biomarker for masked hypertension or metabolic syndrome in obese children and adolescents?

OBJECTIVES

Copeptin, the C-terminal part of arginine-vasopressin, is increased in hypertensive adolescents and closely associated with metabolic syndrome (MS). We aimed to investigate whether serum copeptin can be used to differentiate masked hypertension (MHT) and MS, and the role of sodium intake, natriuretic peptide response and renin-angiotensin-aldosterone system in MHT and MS in obese youth.

METHODS

Obese children aged 10-18 years with normal office blood pressure measurements were included. Patients with MHT and normotension and those with MS and non-MS were evaluated separately. Biochemical parameters, copeptin, brain natriuretic peptide (BNP), aldosterone, renin, urine sodium, and protein were evaluated. Echocardiography, fundoscopic examination, and ambulatory blood pressure monitoring were performed.

RESULTS

There were 80 (M/F=39/41) obese patients with a mean age of 13.78 ± 1.93 years. The cases with MHT, MS, and concomitant MHT and MS were 53,24, and 13%, respectively. Copeptin levels were similar among patients with and without MHT or MS (p>0.05). However, multivariate analysis revealed that copeptin significantly increased the probability of MHT (OR 1.01, 95% CI=1.001-1.018, p=0.033). Copeptin was positively correlated with daytime systolic and diastolic load, aldosterone, BNP, and urine microalbumin/creatinine levels (p<0.05). Linear regression analyses revealed that copeptin was significantly correlated with BNP regardless of having MHT or MS in obese youth. In the MHT group, 24-h sodium excretion was not significantly correlated with BNP.

CONCLUSION

Copeptin may be a beneficial biomarker to discriminate MHT, but not MS in obese children and adolescents. An insufficient BNP response to sodium intake might be one of the underlying causes of MHT in obese cases.

Ambulatory blood pressure profile in office normotensive obese children: prevalence of masked hypertension and impact of parental hypertension

Objectives The objectives of this study were to analyze ambulatory blood pressure (ABP) data in office normotensive obese children, to determine the prevalence and characteristics of masked hypertension (MH) and to investigate the impact of parental hypertension (PH) on ABP. Methods Seventy-nine obese and 35 normal weight children were enrolled. Each weight group was further divided in accordance with the presence of PH. ABP was recorded in an outpatient setting. Results Obese children had higher systolic ABP (p<0.05) and heart rate (p<0.001) compared with normal weight children. In obese children with PH, only nighttime systolic ABP (p=0.01) was higher compared with obese without PH, whereas normal weight children with PH had higher 24 h and daytime systolic and diastolic BP (all p<0.05) and nighttime DBP (p<0.001) compared with those without PH. PH but not obesity was associated with nondipping phenomenon. Prevalence of MH in the whole group was 23.6% being significantly higher in obese than in nonobese subjects (31.6 vs. 5.7%; p=0.0026) as well as in obese subjects with PH compared with obese subjects without PH (48.7 vs. 15%; χ2=10.37; p=0.001). MH was diagnosed more frequently in obese with high-normal office BP compared with obese with normal office BP, although it did not reach statistical significance (50 vs. 26.2%; χ2=3.631; p=0.056). In the normal weight group, neither PH nor office BP category had an impact on the prevalence of MH. Conclusions Office normotensive obese children had higher ABP values. MH was associated with obesity, PH and high-normal BP.

Cardiovascular morbidity, diabetes and cancer risk among children and adolescents with severe obesity

Severe obesity among children and adolescents is a significant global public health concern. The prevalence has markedly increased over the last decades, becoming common in many countries. Overwhelming rates of obesity among youth have prompted efforts to identify an evidence-based immediate- and long-term cardiometabolic risk factor profile in childhood-onset severe obesity, and to highlight gaps that require further investigation. The PubMed database was systematically searched in accordance with PRISMA guidelines. The search yielded 831 results, of which 60 fulfilled stringent criteria and were summarized in this review. The definition of severe obesity was variable, with only one half the publications using the definition BMI > 120% of the 95th percentile. Point estimates of the prevalence of at least one cardiometabolic risk factor in children with severe obesity reportedly range from 67 to 86%. Cross-sectional studies indicate that children and adolescents with severe obesity are at greater risk than those with mild obesity for type 2 diabetes, hypertension, fatty liver disease and dyslipidemia, already at childhood and adolescence. Robust epidemiological data on the long-term risk and actual point estimates in adulthood are lacking for these diseases as well as for other diseases (coronary heart disease, stroke, chronic kidney disease and cancer). Recent longitudinal studies indicate an increased risk for cardiomyopathy, heart failure, cardiovascular mortality and all-cause mortality in adulthood for adolescents with severe obesity compared to those with mild obesity. Given the alarming increase in the prevalence of severe obesity, the persistence of adiposity from childhood to adulthood and the precarious course of young adults with chronic comorbidities, the economic and clinical services burden on the healthcare system is expected to rise.

Updates to pediatric hypertension guidelines: influence on classification of high blood pressure in children and adolescents

Supplemental Digital Content is available in the text

Objective:

The American Academy of Pediatrics updated Clinical Practice Guidelines (CPG) for screening high blood pressure (HBP) in children and adolescents in 2017. This study aimed to assess differences in HBP classification applying this updated HBP definition in a large sample of Chinese youth.

Methods:

Data from 50 336 youth aged 6–17 participating in the 2013 Chinese national survey were analyzed. HBP was diagnosed according to the established (Fourth Report) and updated (2017 CPG) definitions. The associations between HBP with BMI, height, early life factors and behavioral factors were investigated using logistic regression models.

Results:

Applying the CPG definition, 16.7% of children (6–12 years) and 7.9% of adolescents (13–17 years) had HBP, compared with 10.8 and 6.3% applying the Fourth Report definition. Prevalence estimates for HBP differed the greatest for boys, children aged 11, those with high BMI, and those of tall stature. The odds ratios (ORs) for HBP with BMI, height, hip and waist circumference, early life factors and behavioral factors were comparable for the two definitions.

Conclusion:

The new criteria for HBP in young people will lead healthcare providers to diagnose more children as hypertensive. Notably, associations between HBP with BMI and other medical and behavioral factors remained strong, supporting validity of the new definition.

Sex, puberty, and ethnicity have a strong influence on growth and metabolic comorbidities in children and adolescents with obesity: Report on 1300 patients (the Madrid Cohort)

BACKGROUND

The capacity to correctly assess insulin resistance and its role in further obesity-associated metabolic derangement in children is under debate, and its determinants remain largely unknown.

OBJECTIVE

We investigated the association of the insulin secretion profile with other metabolic derangements and anthropometric features in children and adolescents with obesity, exploring the role of ethnicity.

PATIENTS AND METHODS

Growth and metabolic features, including fasting insulin levels and insulin secretory profile in an oral glucose tolerance test (OGTT), were analyzed according to ethnicity in 1300 patients with obesity (75.8% Caucasians/19.0% Latinos).

RESULTS

Height and bone age were influenced by sex, ethnicity, and insulinemia. Latino patients had higher insulin (P < .001), but similar glycemia both prepubertally and postpubertally, compared with Caucasians. Type 2 diabetes was uncommon (0.1%). Impaired glucose tolerance was associated to higher age, BMI, uric acid, and triglyceride levels (all P < .05), as was fasting hyperinsulinism. Impaired fasting glucose or HbA1c 5.7% to 6.4% showed no association with further metabolic derangement. A delayed insulin peak in the OGTT was associated to more severe metabolic disturbances.

CONCLUSIONS

Obesity-associated hyperglycemia is unusual in our environment whereas fasting and late postprandial hyperinsulinemia are highly prevalent, with this being influenced by race and closely related with lipid metabolism impairment.

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.

Uric acid is linked to cardiometabolic risk factors in overweight and obese youths

OBJECTIVE

Observational studies have indicated that high levels of serum uric acid are associated with the risk of cardiovascular disease. The aim of the present study is to investigate the association of uric acid with individual cardiometabolic risk factors, as well as their degree of clustering, in overweight and moderate obese youth.

METHODS

Three hundred and thirty-three Caucasians of both sexes (149 women), from 5-18 years of age from those who underwent an assessment of overweight/obesity. Anthropometric parameters, office and 24-h blood pressure measurements and metabolic profile, including HDL-cholesterol, triglycerides, insulin, HOMA index and uric acid were assessed.

RESULTS

Uric acid was significantly higher in boys than in girls. A positive significant association between uric acid, and office, daytime and night-time SBP, insulin and triglycerides was observed. When boys and girls were grouped by sex-specific uric acid tertiles, a progressive increment was observed in BMI, BMI z-score and waist circumference as well as fasting insulin and HOMA index. In boys, this was also present in office and ambulatory SBP. Likewise, the number of abnormal metabolic risk factors also increases with the uric acid values and the higher the number of metabolic components the higher the uric acid values. Moreover, in a multiple regression analysis, uric acid was significantly related with male sex, waist circumference, both office and night-time SBP and birth weight.

CONCLUSION

The present study found a positive association between uric acid and blood pressure, insulin and triglycerides. As uric acid levels increase there is a relevant clustering of metabolic risk factors, whereas elevated blood pressure is the risk factor less frequently present. Further studies need to assess the mechanistic link between uric acid and the cardiometabolic risk factors.

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.

Does Masked Hypertension Cause Early Left Ventricular Impairment in Youth?

Objectives: Masked hypertension (MH) is not uncommon in the youth and may increase risks of long-term cardiovascular impairment. However, little is known about the subclinical heart damage in this group of patients. Currently, 3-layer speckle tracking imaging based on two-dimensional echocardiography is feasible to detect the early signs of myocardial damage. We therefore aimed to investigate whether subtle changes of cardiac function occurred in the young MH patients by using advanced quantification with layer-specific speckle tracking. Methods: A total of 40 adolescents with MH (age 18 ± 3 years, 73% males) and 40 age-, gender-, race-, and height-matched normotensive volunteers were enrolled in our study. MH was defined as one or more of the ambulatory blood pressure (BP) parameters (24-h, daytime and night-time average BPs) higher than ≥ 95th percentile for gender and height according to the local reference. Both comprehensive two-dimensional echocardiography with layer-specific strain analysis and 24-h ambulatory BP monitoring were performed. Longitudinal strain and circumferential strain in endocardial, mid-myocardial, and epicardial layers were determined accordingly with the dedicated software (EchoPAC software version 201, GE Healthcare, Horten, Norway). Results: Compared with normotensive controls, youths with MH had higher ambulatory pulse rate and left ventricular mass index, and were more obese. Interestingly, similar ventricular volumes and ejection fraction were observed in the study groups, but further analysis with layer-specific strains revealed that endocardial and mid-myocardial longitudinal and circumferential mechanical function were decreased in the young MH subjects when compared to normotensive individuals (all p < 0.05). However, there were no difference regarding radial strain and apical rotation derived from traditional speckle tracking analysis. Conclusion: Subclinical change of LV mechanic function assessed by layer-specific speckle tracking is present in youth with MH despite considered as normal with conventional ways.Thus, MH in youth should be monitored closely instead of labeling as an entirely benign entity.

Relationship between body mass and ambulatory blood pressure: comparison with office blood pressure measurement and effect of treatment

Epidemiologic studies assessing the relationship between blood pressure (BP), body mass and cardiovascular events have primarily been based on office BP measurements, and few data are available in the elderly. The aim of the present study was to evaluate the relationship between body mass index (BMI) and BP values obtained by ambulatory blood pressure monitoring (ABPM) as compared to office BP measurements, and the effect of anti-hypertensive treatment on the relationship. The study population consisted of 813 subjects participating in the Cardiovascular Abnormalities and Brain Lesions (CABL) study who underwent 24-hour ABPM. Office BP (mean of 2 measurements) was found to be associated with increasing BMI, for both SBP (p≤0.05) and DBP (p≤0.001). In contrast, there was no association seen of increasing BMI with ABPM parameters in the overall cohort, even after adjusting for age and gender. However, among subjects not on anti-hypertensive treatment, office SBP and DBP measurements were significantly correlated with increasing BMI (p≤0.01) as were daytime SBP and 24-hour SBP, although with a smaller spread across BMI subgroups compared with office readings. In treated hypertensives, there was only a trend toward increasing office DBP and increasing DBP variability with higher BMI. Our results suggest that body mass may be a less significant influence on BP values in the elderly when ABPM rather than office measurements are considered, particularly in patients receiving anti-hypertensive treatment.

Clinical Practice Guideline for Screening and Management of High Blood Pressure in Children and Adolescents

These pediatric hypertension guidelines are an update to the 2004 "Fourth Report on the Diagnosis, Evaluation, and Treatment of High Blood Pressure in Children and Adolescents." Significant changes in these guidelines include (1) the replacement of the term "prehypertension" with the term "elevated blood pressure," (2) new normative pediatric blood pressure (BP) tables based on normal-weight children, (3) a simplified screening table for identifying BPs needing further evaluation, (4) a simplified BP classification in adolescents ≥13 years of age that aligns with the forthcoming American Heart Association and American College of Cardiology adult BP guidelines, (5) a more limited recommendation to perform screening BP measurements only at preventive care visits, (6) streamlined recommendations on the initial evaluation and management of abnormal BPs, (7) an expanded role for ambulatory BP monitoring in the diagnosis and management of pediatric hypertension, and (8) revised recommendations on when to perform echocardiography in the evaluation of newly diagnosed hypertensive pediatric patients (generally only before medication initiation), along with a revised definition of left ventricular hypertrophy. These guidelines include 30 Key Action Statements and 27 additional recommendations derived from a comprehensive review of almost 15 000 published articles between January 2004 and July 2016. Each Key Action Statement includes level of evidence, benefit-harm relationship, and strength of recommendation. This clinical practice guideline, endorsed by the American Heart Association, is intended to foster a patient- and family-centered approach to care, reduce unnecessary and costly medical interventions, improve patient diagnoses and outcomes, support implementation, and provide direction for future research.

Symmetric ambulatory arterial stiffness index in the young

The ambulatory arterial stiffness index (AASI) and the symmetric ambulatory arterial stiffness index (s-AASI) have been shown to correlate to arterial stiffness in adults. This study assesses these indices with anthropometric and blood pressure (BP) measures in children. A total of 102 children at a pediatric hypertension clinic who had ambulatory blood pressure monitoring (ABPM) done from 2009 to 2013 were included (75% males, 7-22yo, 47% hypertensive, 24% prehypertensive, and 34% white-coat hypertensives). AASI is 1 minus the regression slope of diastolic BP values on systolic BP values from a 24-hour ambulatory blood pressure monitoring. s-AASI is the symmetric regression of AASI. Obese patients had a significantly higher AASI. s-AASI correlated with systolic BP variability. In multivariable regression, BP variability independently correlated with AASI and s-AASI. s-AASI is related to systolic dipping.AASI and s-AASI are highly dependent on BP variability in children. Further studies are necessary to assess their utility.

Association between waist circumference and childhood-masked hypertension: A community-based study

AIM

The aim of this study is to determine the association between waist circumference (WC) and childhood-masked hypertension.

METHODS

A territory-wide, school-based cohort of 1385 Hong Kong students (672 boys and 713 girls) aged 8-17 years was analysed. The ambulatory blood pressure-monitoring assessment was performed using validated oscillometric recorders (A&D TM-2430 (A&D Inc., Tokyo, Japan)) following American Heart Association's recommendations. Subjects were considered normotensive if their casual blood pressure, 24-h daytime and night-time average systolic blood pressure and diastolic blood pressure (DBP) were <95th percentile. If one or more of the ambulatory blood pressure parameters was ≥95th percentile, subjects would be considered suffering from masked hypertension (MH). Subjects who had three successive casual blood pressure measurements above the 95th percentile were excluded.

RESULTS

By body mass index, 148 (10.7%) subjects were obese, 182 (13.1%) overweight and 359 (25.9%) having larger WC (≥85th percentiles). MH was diagnosed in 217 subjects (15.7%). Subjects with larger WC or obesity were significantly associated with higher 24-h daytime and night-time systolic blood pressure (≥95th percentile) (odds ratios from 1.84 to 2.09 and from 2.07 to 3.54 for larger WC and obese respectively, all P < 0.05) as well as 24-h DBP for larger WC (odds ratio = 2, P = 0.015) than normal subjects adjusted by sex, age and height.

CONCLUSION

Waist circumference and body mass index are independent risk factors of childhood and adolescent MH. WC appears a significant associated factor of elevated 24-h DBP in children aged 8-17 years.

Arterial stiffness and SBP variability in children and adolescents

BACKGROUND

The aim of this study was to explore the impact of ambulatory blood pressure (ABP) parameters on arterial stiffness measured by carotid-femoral pulse wave velocity (cf-PWV) in children and adolescents.

METHOD

The study population consisted of 138 consecutive young patients (age range 4-20 years) referred to our hypertension center. Office blood pressure (BP), 24-h ABP monitoring and cf-PWV measurements were performed in all patients. Family history and smoking habits were also recorded.

RESULTS

Among the study population, 10.6% had cf-PWV values equal to or higher than the 95th percentile of the study population. cf-PWV was higher in the hypertensive compared to the normotensive patients, classified by ABP levels even after adjustment for age and sex. Significant correlations were found between cf-PWV and age, weight, height, estimated central pulse pressure (PP), office SBP and DBP, and ABP parameters including 24-h SBP and DBP, weighted 24-h SBP variability, 24-h SBP and DBP load, 24-h mean arterial pressure (MAP), daytime and night-time SBP, daytime and night-time SBP variability, but not with office and 24-h heart rate, 24-h heart rate variability, 24-h daytime and night-time PP, DBP variability, ambulatory arterial stiffeness index and BMI z-score. In analysis of covariance, only weighted 24-h SBP variability (β = 0.28, P < 0.05) and daytime SBP variability (β = 0.15, P < 0.05) were the independent determinants of cf-PWV in children and adolescents.

CONCLUSION

These data may suggest that increased SBP variability is closely associated with arterial stiffness in children and adolescents.

White-Coat and Reverse White-Coat Effects Correlate with 24-h Pulse Pressure and Systolic Blood Pressure Variability in Children and Young Adults

Masked hypertension (MH) and white-coat hypertension (WCH) are associated with organ damage. In the present study, we examined the correlation between the magnitude of white-coat effect (WCE) or reverse WCE (RWCE) and 24-h pulse pressure (PP), an indicator of target organ damage and arterial stiffness, in children and young adults. We also examined the relationship of WCE or RWCE and blood pressure (BP) variability, another predictor of clinical outcomes. One hundred and ninety-eight subjects were studied. According to the office BP and ambulatory BP, they were divided into normotension, WCH, MH, and hypertension. The magnitude of WCE or RWCE, along with male gender and 24-h systolic BP, was the determinant of 24-h PP. In subjects with 24-h PP ≥ 61 mmHg, the magnitude of WCE or RWCE, age, male ratio, height, weight, BMI, the percentage of secondary hypertension, that of MH, office systolic BP, and 24-h systolic BP were significantly greater. There was a progressive increase in 24-h PP from normotension, WCH, MH, to hypertension. BP variability in subjects with MH was numerically highest in both systolic and diastolic. Diastolic BP variability of WCH, MH, and hypertension was significantly higher than that of normotension. Finally, the magnitude of WCE or RWCE in systolic showed a significant correlation with systolic BP variability. In conclusion, the magnitude of WCE or RWCE correlates with 24-h PP and systolic BP variability, which may suggest increased arterial stiffness in WCH and MH.

Prognostic Value of Ambulatory Blood Pressure in the Obese: The Ambulatory Blood Pressure-International Study

The purpose of this study was to compare the predictive value of ambulatory blood pressure (BP) vs office BP for cardiovascular events during a 5.8-year follow-up period in the obese and nonobese participants of the Ambulatory Blood Pressure-International Study (n=10,817). Both ambulatory BP and office BP considered separately were predictive of cardiovascular events. However, in Cox models including both pressures, only ambulatory BP was associated with outcome. Among obese patients, the hazard ratios for a 10-mm Hg increase in 24-hour and office systolic BPs were 1.37 (95% confidence interval, 1.20-1.53) and 0.91 (95% confidence interval, 0.76-1.07), respectively. Among nonobese patients, the corresponding hazard ratios were 1.39 (95% confidence interval, 1.31-1.47) and 0.94 (95% confidence interval, 0.88-1.00) (P=not significant vs obese). Similar results were obtained for diastolic BP and for daytime and nighttime BPs. Ambulatory BP has similar predictive capacity in obese and nonobese patients, suggesting that ambulatory BP monitoring is a useful diagnostic tool for the assessment of obese individuals.

Masked Hypertension in Low-Income South African Adults

While South Africa has one of the highest hypertension rates globally, there are few data on masked hypertension (MHT) and white-coat hypertension (WCHT). This study measured the frequency of MHT and WCHT in low-income (<$500 US per month) South African adults, evaluating cardiovascular risk by arterial stiffness. Participants (n=101, 50% male; mean age 39.4±9.7 years) were recruited from a large North-West Province employer. Clinic and 24-hour blood pressure (BP) and pulse wave analysis were recorded. Clinic BP identified 18% of patients as hypertensive, while 24-hour BP showed that 63% of patients were hypertensive. The frequency of MHT was high (33 of 81, 41%) with only one case of WCHT. In comparison to those with normal clinic and 24-hour BP, augmentation index and pulse wave velocity were significantly higher in those with hypertensive 24-hour BP irrespective of clinic BP, indicating that, in this group, masked and sustained hypertension carry a similar elevated cardiovascular risk.

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.

Obese children and adolescents have elevated nighttime blood pressure independent of insulin resistance and arterial stiffness

BACKGROUND

Insulin resistance has been related to elevated blood pressure (BP) in obese children and may adversely affect the vasculature by arterial stiffening. The objective was to investigate whether daytime and nighttime BP were elevated and related to insulin resistance and arterial stiffness in obese children and adolescents.

METHODS

Ninety-two obese patients aged 10-18 years were compared with 49 healthy control individuals. Insulin resistance was measured as the homeostatic assessment model (HOMA), and arterial stiffness was measured as carotid-femoral pulse wave velocity (cfPWV).

RESULTS

Mean ± SD daytime systolic BP (SBP) (obese: 125±8.3mm Hg; control: 121±10.1mm Hg; P = 0.03) and nighttime SBP (obese: 108±10.7mm Hg; control: 102±8.2mm Hg; P = 0.0001) were higher in the obese group when compared with the control group. No difference was found in daytime diastolic BP (DBP), whereas nighttime DBP (obese: 60±6.6mm Hg; control: 57±4.8mm Hg; P = 0.001) and night-to-day BP ratios were higher in the obese group. Nighttime SBP was related to BMI z score (β = 6.0; 95% confidence interval (CI) = 2.9-9.1; P = 0.0002) and waist/height ratio (β = 36.7; 95% CI = 5.6-67.9; P = 0.02) in the obese group. HOMA index (obese: median = 3.7, interquartile range (IQR) = 2.3-6.0; control: median = 2.6, IQR = 1.8-3.4; P = 0.002) was higher, whereas cfPWV (obese: 4.8±0.8 m/s; control: 5.1±0.6 m/s; P = 0.03) was lower in the obese group. CfPWV was not related to logHOMA index. In multiple regression analyses, the higher nighttime BP in the obese group was independent of logHOMA and cfPWV.

CONCLUSIONS

Obese children had a higher nighttime BP when compared with the control group independently of insulin resistance and arterial stiffness. No relationship was found between insulin resistance and arterial stiffness. CLINICAL TRIAL REGISTRATION Clinicaltrials.gov identifier NCT01310088.

Clinical predictors and impact of ambulatory blood pressure monitoring in pediatric hypertension referrals

Elevated blood pressure (BP) is rising in children. Significant proportions of children have reactive hypertension or masked hypertension, making ambulatory BP monitoring (ABPM) a valuable tool, although with potential economic implications. In youth referred for elevated BP, we sought clinic BP combinations that obviated the need for ABPM and to specify the economic role of ABPM. In a retrospective pediatric referral cohort (N = 170), we examine clinic systolic BP (SBP) predictors of components of ABPM hypertension and their combination. In economic analyses, we compared effectiveness and charges of three diagnostic pathways: (1) clinic BP alone; (2) abnormal clinic BP prompting ABPM; or (3) universal ABPM. ABPM hypertension occurred in 55 (32.4%) and reactive hypertension in 37 (21.8%), average automated (β = 0.208; 95% confidence interval, 0.027, 0.389; P = .03) and maximum auscultatory clinic SBP (β = 0.160; 95% confidence interval 0.022, 0.299; P = .02) were associated with ABPM SBP mean, but none predicted SBP load. No clinic SBP combination was associated with ABPM hypertension. Universal ABPM accrued the lowest average charge per hypertensive youth identified ($10,948). We did not identify a clinic SBP combination that predicted ABPM hypertension in youth referred for elevated BP. Universal ABPM, in this context, may be the most economically and clinically efficient diagnostic strategy.

Ambulatory blood pressure parameters in office normotensive obese and non-obese children: relationship with insulin resistance and atherosclerotic markers

OBJECTIVES

To determine differences in ambulatory blood pressure (ABP) parameters between office normotensive obese and non-obese children and to evaluate correlations of ABP parameters with insulin resistance and the lipid profile.

SUBJECTS AND METHODS

Thirty-eight obese [body mass index (BMI) above the 95th percentile] and 38 non-obese children aged 9-17 years were recruited. All subjects who were normotensive during office visits and who underwent 24-hour ABP monitoring were evaluated. Insulin resistance and the lipid profile were also evaluated.

RESULTS

The mean daytime, night-time and 24-hour systolic blood pressure (SBP) and the daytime and 24-hour diastolic blood pressure (DBP) in normotensive obese children were significantly higher compared to the values in non-obese children (p < 0.05). There was no difference in the frequency of nocturnal non-dippers and nocturnal hypertension (night-time SBP at or above the 95th percentile) between the two groups (p > 0.05). Children with night-time SBP at or above the 95th percentile and non-dippers had higher atherosclerotic markers than children with night-time SBP below the 95th percentile and dippers (p < 0.05). In logistic regression analysis, the low-density lipoprotein cholesterol (LDL-C):high-density lipoprotein cholesterol (HDL-C) ratio and night-time SBP had significantly positive associations with being obese in adolescents (OR 6.54, 95% CI 1.15-37.07, p = 0.03, and OR 1.1, 95% CI 1.01-1.19, p = 0.02, respectively).

CONCLUSION

Normotensive obese children had higher ABP parameters. A high LDL-C:HDL-C ratio and night-time SBP were associated with an increased risk of being obese. High LDL-C:HDL-C ratios and total cholesterol:HDL-C levels in children and adolescents may be risk factors for night-time hypertension.

The impact of different anthropometric measures on sustained normotension, white coat hypertension, masked hypertension, and sustained hypertension in patients with type 2 diabetes

BACKGROUND

Many studies have aimed to determine whether body mass index (BMI), waist circumference (WC), or waist to hip ratio (WHR) best predicts hypertension in diabetic patients, with conflicting results. However, no study has examined the specific relationship between these anthropometric parameters with sustained normotension (SNT), white coat hypertension (WCHT), masked hypertension (MHT), and sustained hypertension (SHT) based on office and ambulatory blood pressure (BP) measurements in these patients.

METHODS

Patients with newly diagnosed type 2 diabetes underwent the following procedures: history taking, measurements of anthropometric parameters, office and ambulatory BP measurements, physical examination, laboratory analysis, and random and 24-hour urine analysis.

RESULTS

In total, there were 65 dippers and 37 nondipper patients. None of the anthropometric parameters were different between the dippers and the nondippers. There were 25 patients with SNT, 32 with WCHT, seven with MHT, and 38 with SHT. A comparison of anthropometric parameters between these four groups of patients showed that WC (P=0.016) and WHR (P=0.015) were different among all groups. According to regression analysis, only BMI was independently related with MHT (odds ratio [OR], 1.373, P=0.022), whereas only WC has been associated with SHT (OR, 1.321, P=0.041).

CONCLUSION

Among anthropometric parameters, only WC and WHR were different in SNT, WCHT, MHT, and SHT in newly diagnosed patients with type 2 diabetes.

Association between obesity and the severity of ambulatory hypertension in children and adolescents

The goal of our study was to analyze the association between obesity and the severity of ambulatory hypertension in obese children. A total of 109 patients with primary obesity ages 7 to 18 years (mean ± SD age 14.1 ± 3.1) were enrolled. Patients were divided into three groups according to body mass index (BMI) Z-scores: group 1 (n = 27): BMI >1.65 and < 3.28 standard deviation scores (SDS); group 2 (n = 55): BMI >3.29 and <4.91 SDS; group 3 (n = 27): BMI >4.92 SDS. Definition and staging of ambulatory hypertension was based on blood pressure (BP) levels and BP load, obtained from ambulatory BP monitoring (ABPM). Only 24% had ambulatory normotension, 25% had ambulatory prehypertension, 3% had hypertension, and 48% had severe ambulatory hypertension. The severity of hypertension increased significantly with the degree of obesity (P = .0027). Daytime systolic, diastolic, and mean arterial BPs increased significantly with increased BMI, whereas the nighttime pressure remained elevated regardless of the degree of obesity. Isolated nighttime hypertension was observed in 25% of patients and 38% were classified as nondippers. Almost 50% of children with obesity and hypertension detected on ABPM suffer from severe ambulatory hypertension. BMI is associated with the severity of ambulatory hypertension and the increase of daytime BP.

Pediatric ambulatory blood pressure monitoring: indications and interpretations

The prevalence of hypertension in children and adolescents is increasing, especially in obese and ethnic children. The adverse long-term effects of hypertension beginning in youth are known; therefore, it is important to identify young patients who need intervention. Unfortunately, measuring blood pressure (BP) is difficult due to the variety of techniques available and innate biologic variation in BP levels. Ambulatory BP monitoring may overcome some of the challenges clinicians face when attempting to categorize a young patient's BP levels. In this article, the authors review the use of ambulatory BP monitoring in pediatrics, discuss interpretation of ambulatory BP monitoring, and discuss gaps in knowledge in usage of this technique in the management of pediatric hypertension.

The role of obesity, salt and exercise on blood pressure in children and adolescents

The increasing trends of blood pressure (BP) in children and adolescents pose great concern for the burden of hypertension-related cardiovascular disease. Although primary hypertension in childhood is commonly associated with obesity, it seems that other factors, such as dietary sodium and exercise, also influence BP levels in children and adolescents. Several studies support that sympathetic nervous system imbalance, impairment of the physiological mechanism of pressure natriuresis, hyperinsulinemia and early vascular changes are involved in the mechanisms causing elevated BP in obese children and adolescents. Under the current evidence on the association of salt intake and BP, dietary sodium restriction appears to be a rational step in the prevention of hypertension in genetically predisposed children and adolescents. Finally, interventional studies show that regular aerobic exercise can significantly reduce BP and restore vascular changes in obese with hypertensive pediatric patients. This article aims to summarize previous studies on the role of obesity, salt intake and exercise on BP in children and adolescents.

Clinical implications of ambulatory and home blood pressure monitoring

Because blood pressure (BP) is an ever changing hemodynamic phenomenon, a BP value, once measured at a physician's office (Office BP), is often unrepresentative of an individual's true BP status. Both ambulatory blood pressure monitoring (ABPM) and home blood pressure monitoring (HBPM) provide more accurate and reproducible estimate of BP, and produce stronger predictive ability for cardiovascular outcome than conventional office BP. Two BP measuring techniques, ABPM and HBPM have been widely in clinical use for the detection and management of hypertension. However, they have different advantages and limitations in practice. At present, it has become crucial to understand the characteristics and clinical implications of these BP measuring techniques for those responsible for the care of hypertensive patients.

Hypertension in adolescents

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

Influence of concurrent obesity and low birth weight on blood pressure phenotype in youth

The aim of this study was to assess the impact of obesity and low birth weight on both office and ambulatory blood pressure (BP) values, as well as on aortic-derived parameters in youths. A total of 422 white youths, from 10 to 18 years of age, were included. Subjects were divided into 4 groups according to the presence (234; 55%) or the absence (188; 45%) of obesity and according to low (114; 27%) or normal (308; 73%, birth weight. Spacelabs 90207 was used to measure ambulatory BP during a 24-hour period. SphygmoCor radial/aortic transform software was used to estimate aortic pressure waveform. Office, 24-hour, daytime, and nighttime systolic BP values were significantly higher in those subjects with low birth weight who became obese. The lowest BP values were present in nonobese subjects in the absence of low birth weight. In the middle, with similar BP values, were nonobese subjects with low birth weight and obese subjects in the absence of low birth weight. No interaction existed between obesity and low birth weight in the office (P=0.165) or ambulatory (P=0.603) systolic BP values. Augmentation index, an estimate of the pulse wave reflection, was significantly higher in the nonobese low birth weight group when compared with the other groups after controlling for height, heart rate, and diastolic BP. A significant interaction between low birth weight and obesity (P<0.005) existed. In conclusion, although the low birth weight children who become obese have the highest systolic BP values, the presence of obesity blunts the increment of the reflecting wave observed in low birth weight subjects.

Home and office blood pressure in children and adolescents: the role of obesity. The Arsakeion School Study

Obesity is related to office blood pressure (OBP). Important discrepancies exist between OBP and home blood pressure (HBP), providing complementary information for the management of hypertension. The association between obesity and HBP has not been investigated in children. The evidence on the role of obesity in the predominance of systolic blood pressure (SBP) over diastolic (DBP) in paediatric hypertension is limited. A total of 778 healthy subjects aged 6-18 years were recruited in this study. OBP and HBP were measured using electronic devices validated in children. Anthropometric measurements were measured and expressed as z-scores for height or age. Among all indices of obesity (z-scores), body mass index (BMI) showed the best association with BP. The effect of obesity (BMI) was more pronounced on: (i) SBP than DBP and (ii) H-SBP than O-SBP (O-SBP: r2=0.09, O-DBP: r2=0.05, H-SBP: r2=0.12, H-DBP: r2=0.06). The prevalence of systolic hypertension was higher than that of diastolic hypertension. This difference was significant only in office readings and independent from obesity (normal weight: 6.3% systolic hypertension versus 1.2% diastolic; obese: 37.9% versus 6.9%, P<0.05 for both). These data imply that in children and adolescents the z-score of BMI is the most appropriate index of the association between BP and obesity. It also suggests that obesity is probably more closely associated with home than office BP. Finally, although obesity appears to affect SBP more than DBP, these results suggest that the predominance of systolic hypertension in children and adolescents might not be only related to obesity but also to the measurement setting (office).

Prevalence, causes, and consequences of masked hypertension: a meta-analysis

BACKGROUND

Masked hypertension (MH) is a relatively newly detected condition of which little is known. More information about MH may help to improve overall antihypertensive health care. We aimed to investigate the prevalence, potential causes, and associated consequences of MH.

METHODS

We searched published literature using MEDLINE, EMBASE, and the Cochrane database completed with references cited in reviews and original study articles. We restricted our research to articles written in the English, German, French, and Spanish language. Studies were included only when the prevalence of MH was reported, office blood pressure (BP) values were given, and methods of BP measurements were described in detail. All data were extracted independently by two readers with a standardized protocol and data-collection form.

RESULTS

The prevalence of MH averaged 16.8% (95% confidence interval 13.0-20.5%). The MH prevalence was 7% for children and 19% for adults. MH prevalences did not differ significantly when determined with self or ambulatory BP measurement (21.1% vs. 16.8%; P = 0.42). Subjects with MH had significantly higher left ventricular mass index (LVMI) values than normotensives (110 vs. 98 g/m2; P < 0.01) but similar values as sustained hypertensives (109 g/m2). In addition, patients with MH were more often smokers than normotensives (mean difference 18%; P < 0.03).

CONCLUSIONS

MH strikes about a quarter of the patients who were initially classified as normotensives (based on office BP measurements) and of treated hypertensives. Patients with MH seem to have a similar cardiovascular risk as sustained hypertensives but they may remain undetected. The presence of MH seems to be a matter of a coincidently low office BP value not related to certain subject characteristics although the chance of its presence may be increased by smoking and antihypertensive treatment.

Circadian variability of blood pressure in obese children

BACKGROUND AND AIMS

The aim of the present study was to evaluate the circadian rhythm of blood pressure pattern in obese children, and to investigate if the lack of normal diurnal rhythm of blood pressure is associated with cardiovascular risk factors.

METHODS AND RESULTS

73 obese children (body weight [mean+/-SD]: 89.0+/-17.8 kg; age [mean+/-SD]: 14.2+/-2.3 years), 42 dippers and 31 non-dippers were investigated. Following ambulatory blood pressure monitoring (ABPM), physical fitness testing was performed on a treadmill. Physical working capacity at 130, -150, -170 beat/min (PWC-130, -150, -170), resting and peak oxygen consumption (VO(2)rest, VO(2)peak) were determined. Forty-two percent of obese children were non-dipper. PWC-130 (74.8+/-48.8 watts; 48.0+/-38.5 watts), PWC-150 (132.9+/-52.1 watts; 104.2+/-49.3 watts), PWC-170 (185.9+/-49.5 watts; 154.9+/-53.4 watts) and VO(2)rest, ([mean+/-SD]: 0.29+/-0.08 L/min; 0.26+/-0.07 L/min), and VO(2) peak (2.77+/-0.61 L/min; 2.44+/-0.62 L/min) were significantly lower in the non-dipper group, as compared to dippers (p<0.05). The prevalence of hypertension, on the basis of ABPM, was significantly higher in the non-dipper group (45.2% vs 83.9%, p<0.001). This is due to increased prevalence of masked hypertension in the non-dipper group (19.0% vs 32.3%, p<0.001).

CONCLUSION

The normal circadian variation of the blood pressure is frequently absent in obese children. Most of the non-dipper obese children are hypertensive, and their physical fitness is decreased.