Subclinical Organ Damage in Children and Adolescents with Hypertension: Current Guidelines and Beyond

Impact of Lipids and Vascular Damage on Early Atherosclerosis in Adolescents with Parental Premature Coronary Artery Disease

AIM

To assess the relationship of cardiovascular risk factors (CRFs) with carotid intima media thickness (IMT) in adolescents with a parental history of premature coronary artery disease (PCAD).

METHODS

This cross-sectional study included 50 healthy adolescents, aged 14-18 years, both sexes, with a parental history of PCAD, that were compared to 50 controls without this history. Questionnaires regarding information of CRFs were applied. Blood chemistry analyses, included lipid profile, lipoprotein (a), low density lipoprotein (LDL) susceptibility to oxidation, and inflammatory cytokine levels. The IMT was evaluated by ultrasound.

RESULTS

The mean age of all participants was 15.9 years. Anthropometric measurements, blood pressure, and lipid profile were similar in both groups. However, the parental history of PCAD group exhibited lower high density lipoprotein cholesterol concentrations, shorter LDL particle oxidation time, and higher lipoprotein (a) levels compared to the control group. IMT was significantly higher in adolescents with a parental history of PCAD compared to controls, (0.53 ± 0.04 mm vs 0.47 ± 0.02 mm, p = 0.001). Among adolescents with a parental history of PCAD, those with ≥ 3 CRFs had significantly higher IMT values (0.56 mm) than those with < 3 CRFs (0.52 mm) and controls (0.48 mm). Multivariable analyses identified that systolic blood pressure and parental history of PCAD explained 26.8% and 16.1% of the variation in IMT. Furthermore, body mass index, LDL-C, ApoB-100, triglycerides and lipoprotein (a) interact with blood pressure levels to explain the IMT values.

CONCLUSION

Adolescents with a parental history of PCAD had higher IMT values than the control group, primary explained by systolic blood pressure and the parental inheritance. Adolescents with parental history of PCAD and ≥ 3 CRFs exhibited the highest IMT values. Notably, lipids and systolic blood pressure jointly contribute to explain IMT in these adolescents.

Aerobic exercise increases brain vessel lumen size and blood flow in young adults with elevated blood pressure. Secondary analysis of the TEPHRA randomized clinical trial

IMPORTANCE

Cerebrovascular changes are already evident in young adults with hypertension and exercise is recommended to reduce cardiovascular risk. To what extent exercise benefits the cerebrovasculature at an early stage of the disease remains unclear.

OBJECTIVE

To investigate whether structured aerobic exercise increases brain vessel lumen diameter or cerebral blood flow (CBF) and whether lumen diameter is associated with CBF.

DESIGN

Open, parallel, two-arm superiority randomized controlled (1:1) trial in the TEPHRA study on an intention-to-treat basis. The MRI sub-study was an optional part of the protocol. The outcome assessors remained blinded until the data lock.

SETTING

Single-centre trial in Oxford, UK.

PARTICIPANTS

Participants were physically inactive (<150 min/week moderate to vigorous physical activity), 18 to 35 years old, 24-hour ambulatory blood pressure 115/75 mmHg-159/99 mmHg, body mass index below 35 kg/m² and never been on prescribed hypertension medications. Out of 203 randomized participants, 135 participated in the MRI sub-study. Randomisation was stratified for sex, age (<24, 24-29, 30-35 years) and gestational age at birth (<32, 32-37, >37 weeks).

INTERVENTION

Study participants were randomised to a 16 week aerobic exercise intervention targeting 3×60 min sessions per week at 60 to 80 % peak heart rate.

MAIN OUTCOMES AND MEASURES

cerebral blood flow (CBF) maps from ASL MRI scans, internal carotid artery (ICA), middle cerebral artery (MCA) M1 and M2 segments, anterior cerebral artery (ACA), basilar artery (BA), and posterior cerebral artery (PCA) diameters extracted from TOF MRI scans.

RESULTS

Of the 135 randomized participants (median age 28 years, 58 % women) who had high quality baseline MRI data available, 93 participants also had high quality follow-up data available. The exercise group showed an increase in ICA (0.1 cm, 95 % CI 0.01 to 0.18, p =.03) and MCA M1 (0.05 cm, 95 % CI 0.01 to 0.10, p =.03) vessel diameter compared to the control group. Differences in the MCA M2 (0.03 cm, 95 % CI 0.0 to 0.06, p =.08), ACA (0.04 cm, 95 % CI 0.0 to 0.08, p =.06), BA (0.02 cm, 95 % CI -0.04 to 0.09, p =.48), and PCA (0.03 cm, 95 % CI -0.01 to 0.06, p =.17) diameters or CBF were not statistically significant. The increase in ICA vessel diameter in the exercise group was associated with local increases in CBF.

CONCLUSIONS AND RELEVANCE

Aerobic exercise induces positive cerebrovascular remodelling in young people with early hypertension, independent of blood pressure. The long-term benefit of these changes requires further study.

TRIAL REGISTRATION

Clinicaltrials.gov NCT02723552, 30 March 2016.

Hypertension-Mediated Organ Damage: Prevalence, Correlates, and Prognosis in the Community

BACKGROUND

Guidelines emphasize screening people with elevated BP for the presence of end-organ damage.

METHODS

We characterized the prevalence, correlates, and prognosis of hypertension-mediated organ damage (HMOD) in the community-based Framingham Study. 7898 participants (mean age 51.6 years, 54% women) underwent assessment for the following HMOD: electrocardiographic and echocardiographic left ventricular hypertrophy, abnormal brain imaging findings consistent with vascular injury, increased carotid intima-media thickness, elevated carotid-femoral pulse wave velocity, reduced kidney function, microalbuminuria, and low ankle-brachial index. We characterized HMOD prevalence according to blood pressure (BP) categories defined by four international BP guidelines. Participants were followed up for incidence of cardiovascular disease.

RESULTS

The prevalence of HMOD varied positively with systolic BP and pulse pressure but negatively with diastolic BP; it increased with age, was similar in both sexes, and varied across BP guidelines based on their thresholds defining hypertension. Among participants with hypertension, elevated carotid-femoral pulse wave velocity was the most prevalent HMOD (40%-60%), whereas low ankle-brachial index was the least prevalent (<5%). Left ventricular hypertrophy, reduced kidney function, microalbuminuria, increased carotid intima-media thickness, and abnormal brain imaging findings had an intermediate prevalence (20%-40%). HMOD frequently clustered within individuals. On follow-up (median, 14.1 years), there were 384 cardiovascular disease events among 5865 participants with concurrent assessment of left ventricular mass, carotid-femoral pulse wave velocity, kidney function, and microalbuminuria. For every BP category above optimal (referent group), the presence of HMOD increased cardiovascular disease risk compared with its absence.

CONCLUSIONS

The prevalence of HMOD varies across international BP guidelines based on their different thresholds for defining hypertension. The presence of HMOD confers incremental prognostic information regarding cardiovascular disease risk at every BP category.

Causative Mechanisms of Childhood and Adolescent Obesity Leading to Adult Cardiometabolic Disease: A Literature Review

The past few decades have shown a worrisome increase in the prevalence of obesity and its related illnesses. This increasing burden has a noteworthy impact on overall worldwide mortality and morbidity, with significant economic implications as well. The same trend is apparent regarding pediatric obesity. This is a particularly concerning aspect when considering the well-established link between cardiovascular disease and obesity, and the fact that childhood obesity frequently leads to adult obesity. Moreover, most obese adults have a history of excess weight starting in childhood. In addition, given the cumulative character of both time and severity of exposure to obesity as a risk factor for associated diseases, the repercussions of obesity prevalence and related morbidity could be exponential in time. The purpose of this review is to outline key aspects regarding the current knowledge on childhood and adolescent obesity as a cardiometabolic risk factor, as well as the most common etiological pathways involved in the development of weight excess and associated cardiovascular and metabolic diseases.

Relative children's lipid accumulation with hypertension in Chinese children and adolescents

Background

This study aimed to develop a novel indicator associated with hypertension in Chinese children and adolescents, the relative children’s lipid accumulation product (RCLAP).

Methods

A cross-sectional study was conducted in 2018. A total of 683 students aged 8–15 years were recruited via a stratified cluster sampling Methods. Anthropometric indexes (waist circumference (WC), Body mass index (BMI), Waist-height ratio (WHtR), logarithm children LAP (LnCLAP), RCLAP per height (RCLAP-H)) were standardized using a z-score method (standardized variables: SWC, SBMI, SWHtR, SLnCLAP, SRCLAP-H). A logistic regression model was performed to evaluate the association of the above indicators with the outcome of hypertension.

Results

The overall prevalence of hypertension was 5.7% (5.5% in boys, 6.0% in girls). SWC ≥ P₇₅, SBMI ≥ P₇₅, SWHtR ≥ P₇₅, SlnCLAP ≥ P₇₅ and SRCLAP-H ≥ P₇₅ significantly increased risk of hypertension, with odds ratios (OR) of 2.21 (95% confidence interval (CI): 1.13, 4.30), 2.30 (1.18, 4.49), 2.64 (1.35, 5.14), 4.43 (2.28, 8.61), and 4.49 (2.31, 8.71), respectively.

Conclusion

RCLAP is a novel indicator associated with hypertension in Chinese children and adolescents, and it performs better than WC, BMI, WHtR and children LAP.

The mediating role of adiposity in the longitudinal association between cardiorespiratory fitness and blood pressure in adolescents: LabMed cohort study

BACKGROUND

The aim of this prospective cohort study was to examine whether the association between the cardiorespiratory fitness (CRF) at baseline and blood pressure (BP) at follow-up is mediated by adiposity in adolescents.

MATERIALS AND METHODS

The sample comprised 734 adolescents (349 girls) aged 12-18 years from the LabMed Physical Activity Cohort Study. The variables of interest were measured in 2011 (baseline) and in 2013 (2-year follow-up). CRF was assessed by the 20-m shuttle run test. Body mass index, waist circumference, body fat percentage, pubertal status and resting BP were assessed according to standard procedures. Boot-strapped mediation procedures were performed, and indirect effects (IE) with confidence intervals (CI) not including zero were considered statistically significant.

RESULTS

After adjusting for potential confounders, body mass index acted as a mediator of the relationship between CRF and systolic BP (IE = -0. 023; CI = -0.039; -0.009), pulse pressure (IE = -0.023; CI = -0.034; -0.012) and rate product pressure (IE = -2.839; CI = -5.329; -0.340). Similar results were obtained for waist circumference as mediator for systolic BP (IE = -0.019; CI = -0.033; -0.005), pulse pressure (IE = -0.017; CI = -0.028; -0.007) and rate product pressure (IE = -3.793; CI = -6.097; -1.689). Likewise, body fat percentage mediated the association for: systolic BP (IE = -0.029; CI = -0.048; -0.010), pulse pressure (IE = -0.027; CI = -0.041; -0.013) and rate product pressure (IE = -4.280; CI = -7.488; -1.264).

CONCLUSIONS

Adiposity mediated the association between CRF and BP in adolescents. Therefore, both optimal CRF and adiposity levels are important to maintain normal BP ranges throughout adolescence.