The effect of known cardiovascular risk factors on carotid-femoral pulse wave velocity in school-aged children: a population based twin study

Association of Blood Pressure-Related Increase in Vascular Stiffness on Other Measures of Target Organ Damage in Youth

BACKGROUND

Hypertension-related increased arterial stiffness predicts development of target organ damage (TOD) and cardiovascular disease. We hypothesized that blood pressure (BP)-related increased arterial stiffness is present in youth with elevated BP and is associated with TOD.

METHODS

Participants were stratified by systolic BP into low- (systolic BP <75th percentile, n=155), mid- (systolic BP ≥80th and <90th percentile, n=88), and high-risk BP categories (≥90th percentile, n=139), based on age-, sex- and height-specific pediatric BP cut points. Clinic BP, 24-hour ambulatory BP monitoring, anthropometrics, and laboratory data were obtained. Arterial stiffness measures included carotid-femoral pulse wave velocity and aortic stiffness. Left ventricular mass index, left ventricular systolic and diastolic function, and urine albumin/creatinine were collected. ANOVA with Bonferroni correction was used to evaluate differences in cardiovascular risk factors, pulse wave velocity, and cardiac function across groups. General linear models were used to examine factors associated with arterial stiffness and to determine whether arterial stiffness is associated with TOD after accounting for BP.

RESULTS

Pulse wave velocity increased across groups. Aortic distensibility, distensibility coefficient, and compliance were greater in low than in the mid or high group. Significant determinants of arterial stiffness were sex, age, adiposity, BP, and LDL (low-density lipoprotein) cholesterol. Pulse wave velocity and aortic compliance were significantly associated with TOD (systolic and diastolic cardiac function and urine albumin/creatinine ratio) after controlling for BP.

CONCLUSIONS

Higher arterial stiffness is associated with elevated BP and TOD in youth emphasizing the need for primary prevention of cardiovascular disease.

The Role of Urate in Cardiovascular Risk in Adolescents and Young Adults With Hypertension, Assessed by Pulse Wave Velocity

Background

Urate is increasingly recognized as a cardiovascular risk factor. It has been associated with hypertension, metabolic syndrome, obesity, chronic kidney disease and diabetes. Its prognostic role is less clear. The aim of our study was to evaluate the association between serum urate and pulse wave velocity, a measure of arterial stiffness in hypertensive adolescents and young adults.

Methods

269 adolescents and young adults with hypertension were included in the study. From all, anthropometric, blood pressure, pulse wave velocity and serum urate measurements were made. Variables were compared between sex, participants with or without obesity and with or without elevated urate.

Results

In multiple regression analysis for urate as dependent variable gender and diastolic pressure were found to be statistically significant. The difference between urate levels were found between boys and girls (p < 0.001), obese and non-obese (p < 0.001); however, pulse wave velocity did not differ between hyper- and eu-uricemic group (p = 0.162).

Conclusion

Associations between urate, gender, diastolic blood pressure and obesity were confirmed, however, no significant associations between pulse wave velocity and urate were detected.

Association of blood pressure, obesity and physical activity with arterial stiffness in children: a systematic review and meta-analysis

Central pulse wave velocity (cPWV) is a biomarker for cardiovascular (CV) risk and a predictor for CV events in adulthood. Alterations of arterial stiffness have also been associated with CV risk in childhood. The study aimed to systematically review and meta-analyze the association of blood pressure (BP), body mass index (BMI), and cardiorespiratory fitness (CRF) with cPWV in children. Literature search was through the databases PubMed, Web of Science, Embase and the Cochrane Register of Controlled Trials. Twenty-two articles were included in the systematic review and eight articles in the meta-analysis. Higher systolic and diastolic BP were associated with higher cPWV (pooled estimated effect size (ES) 0.02 (95% CI: 0.012-0.027; P < 0.001), and ES 0.02 (95% CI: 0.011-0.029; P < 0.001); respectively). Higher BMI correlated with higher cPWV (ES 0.025 (95% CI: 0.013-0.038; P < 0.001)). CRF was inversely associated with cPWV (ES -0.033 (95% CI: -0.055 to -0.011; P = 0.002)). In children, higher BP and BMI are already related to increased cPWV, and enhanced CRF may be a preventive strategy to counteract development of CV disease later in life. IMPACT: This meta-analysis suggests that elevated blood pressure and body mass index in childhood correlate with increased central pulse wave velocity. Children with higher cardiorespiratory fitness appear to have favorably lower arterial stiffening. Elevated blood pressure and altered arterial stiffness originate early in life and childhood risk stratification as well as timely initiation of exercise treatment may help counteract development of manifest cardiovascular disease later in life.

Cardiometabolic Health and Carotid-Femoral Pulse Wave Velocity in Children: A Systematic Review and Meta-Regression

OBJECTIVE

To identify, in children the normal rate of carotid-femoral pulse wave velocity (cfPWV) progression, and whether presence of cardiometabolic risk factors is associated with cfPWV.

STUDY DESIGN

Electronic databases (PubMed, Google Scholar) were searched from inception to May 2018, for all studies which reported cfPWV in children (<19 years of age). Random effects meta-regression quantified the association between time (years) and cfPWV, and a systematic review was performed to determine whether cardiometabolic risk factors are associated with cfPWV.

RESULTS

Data from 28 articles were eligible for inclusion, including 9 reference value (n = 13 100), 5 cardiovascular risk (n = 5257), 10 metabolic risk (n = 2999), and 8 obesity-focused (n = 8760) studies. Meta-regression findings (9 studies) showed that the increase in cfPWV per year (age) was 0.12 m/second (95% CI, 0.07-0.16 m/second) per year, and when stratified by sex the CIs overlapped. Systematic review findings showed that cardiometabolic risk factors were positively associated with cfPWV, including positive associations with blood pressure, impaired glucose metabolism, and metabolic syndrome. However, obesity was not consistently associated with cfPWV.

CONCLUSIONS

Arterial stiffness in children progresses with age and is associated with cardiometabolic risk factors. Although further longitudinal studies are warranted, the presented reference data will be valuable to epidemiologists tracking children, and to scientists and clinicians prescribing therapies to mitigate risk in a population that is increasingly more vulnerable to cardiovascular disease.

Static cut-points of hypertension and increased arterial stiffness in children and adolescents: The International Childhood Vascular Function Evaluation Consortium

Pediatric elevated blood pressure (BP) and hypertension are usually defined using traditional BP tables at the 90th and 95th percentiles, respectively, based on sex, age, and height, which are cumbersome to use in clinical practice. The authors aimed to assess the performance of the static cut-points (120/80 mm Hg and 130/80 mm Hg for defining elevated BP and hypertension for adolescents, respectively; and 110/70 mm Hg and 120/80 mm Hg for children, respectively) in predicting increased arterial stiffness. Using data from five population-based cross-sectional studies conducted in Brazil, China, Korea, and New Zealand, a total of 2546 children and adolescents aged 6-17 years were included. Increased arterial stiffness was defined as pulse wave velocity ≥sex-specific, age-specific, and study population-specific 90th percentile. Compared to youth with normal BP, those with hypertension defined using the 2017 American Academy of Pediatrics guideline (hereafter referred to as "percentile-based cut-points") and the static cut-points were at similar risk of increased arterial stiffness, with odds ratios and 95% confidence intervals of 2.35 (1.74-3.17) and 3.07 (2.20-4.28), respectively. Area under the receiver operating characteristic curve and net reclassification improvement methods confirmed the similar performance of static cut-points and percentile-based cut-points (P for difference > .05). In conclusion, the static cut-points performed similarly well when compared with the percentile-based cut-points in predicting childhood increased arterial stiffness. Use of static cut-points to define hypertension in childhood might simplify identification of children with abnormal BP in clinical practice.

Increased Arterial Stiffness in Adolescents With Obesity

Increased arterial stiffness (AS) is an early sign of cardiovascular disease. Influence of weight, puberty, and insulin resistance (IR) on AS in adolescents is unclear. Therefore, this study compared AS, assessed with pulse wave velocity (PWV) and augmentation index (AIx), of adolescents with and without obesity and evaluated the influence of puberty and IR on AS. Sixty-two lean and 61 adolescents with obesity were included. Significantly higher PWV was observed in adolescents with obesity (4.1 ms⁻¹ [2.4 to 5.6 ms⁻¹] vs 3.6 ms⁻¹ [0.4 to 6.1 ms⁻¹]; P = .01), while AIx was not significant different. However, significantly higher AIx was observed in adolescents with obesity and IR (3.0 [−17.5% to 28.5%] vs −3.0 [−19.0% to 13.0%]; P = .01). For Tanner stages, no differences were observed. The higher PWV in adolescents with obesity and higher AIx in adolescents with obesity and IR both indicate an increased AS. Consequently, measurement of AS should be considered in adolescents with obesity and IR as part of cardiovascular risk assessment.

Utility of arterial stiffness assessment in children

Atherosclerotic cardiovascular disease is a leading cause of death and disability worldwide, and the atherosclerotic process begins in childhood. Prevention or containment of risk factors that accelerate atherosclerosis can delay the development of atherosclerotic cardiovascular disease. Although current recommendations are to periodically screen for commonly prevailing risk factors for atherosclerosis in children, a single test that could quantify the cumulative effect of all risk factors on the vasculature, thus assessing arterial health, would be helpful in further stratifying risk. Measurement of pulse wave velocity and assessment of augmentation index - measures of arterial stiffness - are easy-to-use, non-invasive methods of examining arterial health. Various studies have assessed pulse wave velocity and augmentation index in children with commonly occurring conditions including obesity, hypertension, insulin resistance, diabetes mellitus, dyslipidaemia, physical inactivity, chronic kidney disease, CHD and acquired heart diseases, and in children who were born premature or small for gestational age. This article summarises pulse wave velocity and augmentation index assessments and the effects of commonly prevailing chronic conditions on arterial health in children. In addition, currently available reference values for pulse wave velocity and augmentation index in healthy children are included. Further research to establish widely applicable normative values and the effect of lifestyle and pharmacological interventions on arterial health in children is needed.

Circulating miR-92a expression level in patients with essential hypertension: a potential marker of atherosclerosis

MicroRNAs (miRs) are key posttranscriptional regulators of gene expression in all eukaryotic cells and have a vital role in the evolution of hypertension and cardiovascular remodelling and, therefore, have emerged as potential biomarkers for cardiovascular disease. We assessed 240 participants, including 60 healthy volunteers with normal carotid intima-media thickness (nCIMT), 60 healthy volunteers with increased CIMT (iCIMT), 60 hypertensive patients with nCIMT and 60 hypertensive patients with iCIMT. All patients underwent measurements of CIMT, carotid-femoral pulse wave velocity (cfPWV) and ambulatory blood pressure (BP) monitoring. Plasma miR-92a expression was quantified by real-time reverse transcription PCR. Correlations between miR-92a expression and BP parameters, CIMT and cfPWV were assessed using the Spearman correlation coefficient. We observed the lowest miR-92a expression (24.59±1.30 vs 27.76±2.13 vs 29.29±1.89 vs 33.76±2.08; P<0.001) in healthy controls with nCIMT, followed by healthy controls with iCIMT, then hypertensive patients with nCIMT and the highest expression in hypertensive patients with iCIMT. Additionally, MiR-92a levels showed a significant positive correlation with 24-h mean systolic BP (r=0.807, P<0.001), 24-h mean diastolic BP (r=0.649, P<0.001), 24-h mean pulse pressure (PP) (r=0.697, P<0.001), 24-h daytime PP (r=0.654, P<0.001), 24-h nighttime PP (r=0.573, P<0.001), CIMT (r=0.571, P<0.001) and cfPWV (r=0.601, P<0.001). Our data present significant evidence that circulating miR-92a represents a potential noninvasive atherosclerosis marker in essential hypertensive patients.