Insulin resistance and arterial stiffness in healthy adolescents and young adults

Cumulative insulin resistance and hyperglycemia with arterial stiffness and carotid IMT progression in 1,779 adolescents: a 9-yr longitudinal cohort study

In pediatric population with diabetes and obesity, insulin resistance (HOMA-IR) has been associated with worsening vascular outcomes, however, the cumulative role of HOMA-IR, hyperglycemia, and hyperinsulinemia on repeatedly measured vascular outcomes in asymptomatic youth is unknown. We examined the longitudinal associations of fasting glucose, insulin, and HOMA-IR with carotid-femoral pulse wave velocity (cfPWV) and carotid intima-media thickness (cIMT). From the Avon Longitudinal Study of Parents and Children (ALSPAC) birth cohort, UK 1,779, 15-yr-old participants were followed up for 9 yr. Glucose, insulin, and HOMA-IR assessed at 15, 17, and 24 yr and sex-specifically dichotomized as ≥75th percentile, indicating high category and <75th percentile as reference. cfPWV and cIMT were measured at ages 17 and 24 yr. Associations were examined using linear mixed-effect models adjusted for cardiometabolic and lifestyle covariates. Among 1,779 participants [49.9% female], glucose, insulin, and HOMA-IR had a J- or U-shaped increase from ages 15 through 24 yr. The cumulative exposures to hyperinsulinemia effect estimate -0.019 mU/L; [95% CI -0.019 to -0.002; P = 0.033] and high HOMA-IR: -0.021; [-0.039 to -0.004; P = 0.019] from 15 to 24 yr of age were negatively associated with the 7-yr cfPWV progression. Only cumulative hyperinsulinemia and high HOMA-IR from ages 15 to 17 yr but not from ages 17 to 24 yr was associated with decreased cfPWV progression. There were no associations between cumulative hyperglycemia and cfPWV or cIMT progression. Hyperinsulinemia and HOMA-IR were not associated with cIMT progression. In conclusion, late adolescence may be an optimal timing for intervention targeted at sustaining the protective effect of the decline of insulin and insulin resistance on arterial stiffness progression.NEW & NOTEWORTHY Fasting plasma glucose, insulin, and insulin resistance had a J- or U-shaped increase from 15 to 24 yr with the base of the curve at age 17 yr. Cumulative high insulin and high insulin resistance from 15 to 24 yr were negatively associated with arterial stiffness progression from ages 17 to 24 yr. Age 17 yr may be an optimal timing for intervention targeted at sustaining the protective effect of the decline of insulin and insulin resistance on arterial stiffness progression.

Effects of helminths and anthelmintic treatment on cardiometabolic diseases and risk factors: A systematic review

BACKGROUND

Globally, helminth infections and cardiometabolic diseases often overlap in populations and individuals. Neither the causal relationship between helminth infections and cardiometabolic diseases nor the effect of helminth eradication on cardiometabolic risk have been reviewed systematically in a large number of human and animal studies.

METHODS

We conducted a systematic review assessing the reported effects of helminth infections and anthelmintic treatment on the development and/or severity of cardiometabolic diseases and risk factors. The search was limited to the most prevalent human helminths worldwide. This study followed PRISMA guidelines and was registered prospectively in PROSPERO (CRD42021228610). Searches were performed on December 10, 2020 and rerun on March 2, 2022 using Ovid MEDLINE ALL (1946 to March 2, 2022), Web of Science, Cochrane Library, Global Index Medicus, and Ovid Embase (1974 to March 2, 2022). Randomized clinical trials, cohort, cross-sectional, case-control, and animal studies were included. Two reviewers performed screening independently.

RESULTS

Eighty-four animal and human studies were included in the final analysis. Most studies reported on lipids (45), metabolic syndrome (38), and diabetes (30), with fewer on blood pressure (18), atherosclerotic cardiovascular disease (11), high-sensitivity C-reactive protein (hsCRP, 5), and non-atherosclerotic cardiovascular disease (4). Fifteen different helminth infections were represented. On average, helminth-infected participants had less dyslipidemia, metabolic syndrome, diabetes, and atherosclerotic cardiovascular disease. Eleven studies examined anthelmintic treatment, of which 9 (82%) reported post-treatment increases in dyslipidemia, metabolic syndrome, and diabetes or glucose levels. Results from animal and human studies were generally consistent. No consistent effects of helminth infections on blood pressure, hsCRP, or cardiac function were reported except some trends towards association of schistosome infection with lower blood pressure. The vast majority of evidence linking helminth infections to lower cardiometabolic diseases was reported in those with schistosome infections.

CONCLUSIONS

Helminth infections may offer protection against dyslipidemia, metabolic syndrome, diabetes, and atherosclerotic cardiovascular disease. This protection may lessen after anthelmintic treatment. Our findings highlight the need for mechanistic trials to determine the pathways linking helminth infections with cardiometabolic diseases. Such studies could have implications for helminth eradication campaigns and could generate new strategies to address the global challenge of cardiometabolic diseases.

Changes in Arterial Stiffness in Response to Various Types of Exercise Modalities: A Narrative Review on Physiological and Endothelial Senescence Perspectives

Arterial stiffness is a reliable independent predictor of cardiovascular events. Exercise training might enhance arterial compliance through improved metabolic health status. Different modes of exercise may have different effects on arterial stiffness. However, the interactions among different modes of exercise on endothelial senescence, the development of arterial vascular stiffness, and the associated molecular mechanisms are not completely understood. In this narrative review, we evaluate the current evidence focusing on the effects of various exercise modes on arterial stiffness and vascular health, and the known underlying physiological mechanisms are discussed as well. Here, we discuss the most recent evidence of aerobic exercise, high-intensity interval training (HIIT), and resistance exercise (RE) on arterial stiffness and endothelial senescence in physiological and cellular studies. Indeed, aerobic, HIIT, and progression RE-induced arterial compliance may reduce arterial stiffness by effectively promoting nitric oxide (NO) bioavailability and reducing endothelial senescence. However, the transient increase in inflammation and sympathetic activation may contribute to the temporary elevation in arterial stiffness following whole-body high-intensity acute resistance exercise.

Arterial stiffness precedes hypertension and metabolic risks in youth: a review

Arterial stiffness is a strong predictor of cardiovascular events and all-cause mortality in middle-aged and old adults. Arterial stiffness has been limited to being an intermediate marker of atherosclerotic cardiovascular events in adolescents and young adult studies. The paucity of normative longitudinal data and repeated gold-standard assessments of arterial stiffness among the young population has occasioned a huge knowledge gap in its clinical utility. This review summarizes recent longitudinal evidence in a large adolescent population, supporting the value of arterial stiffness as a novel risk factor for hypertension, overweight/obesity and insulin resistance. Preventing or decreasing arterial stiffness during adolescence may confer cardiometabolic health benefits in later life, but further pathological and mechanistic research is needed. The review also offers suggestions for incorporating arterial stiffness measures into routine paediatric and young adult clinical practice.

Visceral fat and arterial stiffness in youth with healthy weight, obesity, and type 2 diabetes

BACKGROUND AND OBJECTIVES

Visceral fat is associated with increased cardiovascular risk in adults, but studies in youth are limited. We assessed associations between visceral fat and arterial stiffness in youth with healthy weight, obesity and type 2 diabetes and determined whether relationships were independent of clinical estimates of body fatness.

METHODS

This cross-sectional sample included youth ages 10-23 years (67% female, 56% non-black) with healthy weight (body mass index [BMI] = 5th-85th percentile, n = 236), obesity (BMI ≥ 95th percentile, n = 224) and type 2 diabetes (BMI ≥ 95th percentile, n = 145). Visceral fat was assessed via dual-energy X-ray absorptiometry. Carotid-femoral pulse wave velocity (PWV) was assessed via applanation tonometry. Obesity and type 2 diabetes groups were combined for final analyses. Analyses accounted for age, sex, ancestry and mean arterial pressure.

RESULTS

Visceral fat and PWV were greater in youth with obesity versus healthy weight (p < 0.001). In youth with obesity, but not healthy weight, visceral fat was positively associated with PWV (p < 0.001) and was predictive of PWV beyond BMI and waist circumference.

CONCLUSIONS

Visceral fat likely contributes to subclinical cardiovascular complications in youth. Since cardiovascular health tracks from adolescence to adulthood, longitudinal studies in youth with obesity are required to define the role of visceral fat in lifelong cardiovascular disease risk.

Multiple non-invasive peripheral vascular function parameters with obesity and cardiometabolic risk indicators in school-aged children

Background

The Peripheral Arterial Tonometry (PAT) technique measured by Endo-PAT™, is recently introduced for peripheral vascular assessment in youth, primarily benefits from its easy and non-invasive operation. However, the value of Endo-PAT as early indicator of obesity-related cardiometabolic risk factors remains unclear, with few studies focusing solely on Reactive Hyperemia Index (RHI). A wider coverage of Endo-PAT algorithms is recommended to be applied simultaneously in youth. We evaluated the value of multiple Endo-PAT parameters on obesity and cardiometabolic risk indication in school-aged children, in comparison with another non-invasive Brachial-ankle Pulse Wave Velocity (BaPWV) method.

Methods

This cross-sectional sample included 545 youth (80 with overweight and 73 with obesity) aged 7–17 years. RHI, Framingham-Reactive Hyperemia Index (F-RHI), peak response and Augmentation Index normalized to Heart Rate 75 bpm (AIx75) were measured by Endo-PAT™ 2000 device. Spearman correlations of abovementioned Endo-PAT parameters and BaPWV, with adiposity (weight, waist circumference, BMI, body fat mass) and cardiometabolic indicators (glycemic response, blood pressure, lipid profiles) were calculated with non-linear adjustment on age, height, gender and baseline pulse-wave amplitude (PWA) using fractional polynomials. Analysis was repeated in students with obesity only [median BMI z score: 3.0 (2.5,3.5)] for sensitivity analysis.

Results

The correlations of Endo-PAT parameters with adiposity measures and cardiometabolic indicators were overall mixed and weak (DBP: r ranged from − 0.20 to − 0.13, others: |r| < 0.1) after adjustment. Except that body fat mass (AIx75: r = 0.52 p < 0.01) and triglyceride level (RHI: r = − 0.32 p < 0.01, F-RHI: r = − 0.21 p > 0.05) was moderately reversed in students with obesity. In contrast, BaPWV showed consistently moderate correlations (|r| ranged from 0.123 to 0.322, p < 0.05) with almost all adiposity measures and cardiometabolic indicators regardless of obesity status.

Conclusion

Contrary to previous suggestion, various Endo-PAT parameters performed similarly weak for early cardiometabolic risk indication in school-aged children, and less preferable than that by another non-invasive BaPWV method. Despite further investigation is needed to improve certainty of relevant research evidence, innovative technology and algorithms taking into account specifics of young population are worthy of consideration.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-022-03214-4.

Non-alcoholic/Metabolic-Associated Fatty Liver Disease and Helicobacter pylori Additively Increase the Risk of Arterial Stiffness

Background

Non-alcoholic fatty liver disease (NAFLD) and Helicobacter pylori (Hp) infection have a close association with an increased risk of cardiovascular disease. Metabolic dysfunction-associated fatty liver disease (MAFLD) is characterized by metabolic dysfunction in NAFLD. We investigated the synergistic effects of NAFLD/MAFLD and Hp infection on the risk of arterial stiffness in an asymptomatic population.

Methods

We included individuals who underwent abdominal ultrasonography, anti-Hp IgG antibody evaluations and cardio-ankle vascular index (CAVI) during health screening tests between January 2013 and December 2017. Arterial stiffness was defined using CAVI. A logistic regression model was used to analyze the independent and synergistic effects of NAFLD/MAFLD and Hp infection on the risk of arterial stiffness.

Results

Among 3,195 subjects (mean age 54.7 years, 68.5% male), the prevalence of increased arterial stiffness was 36.4%. In the multivariate analysis, subjects with NAFLD but without Hp infection and those with both NAFLD and Hp infection had a significantly higher risk of increased arterial stiffness [odds ratio (OR) 1.61, 95% confidence interval (CI) 1.15–2.26, and OR 2.23, 95% CI 1.63–3.06, respectively], than subjects without Hp infection and NAFLD. Regarding MAFLD, Hp infection additively increased the risk of arterial stiffness in subjects with MAFLD (OR 2.13, 95% CI 1.64–2.78).

Conclusions

An interactive effect of Hp infection on the risk of arterial stiffness in individuals with NAFLD/MAFLD was observed. Hp infection additively increases the risk of arterial stiffness in subjects with NAFLD or MAFLD.

Association of triglyceride-glucose index with intra- and extra-cranial arterial stenosis: a combined cross-sectional and longitudinal analysis

PURPOSE

This study aimed to assess the cross-sectional and longitudinal associations of the triglyceride glucose (TyG) index, a simple surrogate marker of insulin resistance, with intra-cranial and extra-cranial artery stenosis (ICAS and ECAS) in Chinese adults.

METHODS

Participants were recruited from the Asymptomatic Polyvascular Abnormalities Community study, 5381 participants were enrolled in the cross-sectional analysis, then 3447 and 1853 participants in the longitudinal analysis for incident ICAS and ECAS, respectively. The TyG index was calculated as ln [fasting triglyceride (mg/dL) × fasting glucose (mg/dL)/2]. Multivariable logistic analysis was used to calculate odds ratio (OR) and 95% confidence interval (CI).

RESULTS

The results of the cross-sectional and longitudinal analysis were basically the same, as the fully adjusted OR comparing participants in the highest tertile versus lowest tertile of the TyG index was 1.34 (95% CI, 1.13-1.59) for the prevalence of ECAS and 1.85 (95% CI, 1.26-2.71) for incident ECAS, respectively. The addition of TyG index to a conventional model had an incremental effect on the predictive value for ECAS. However, we did not observe any significant association between the TyG index and ICAS.

CONCLUSIONS

Elevated TyG index was significantly associated with a higher risk of ECAS, but not with ICAS in Chinese adults. This conclusion lends support to the clinical significance of the TyG index for the assessment of artery stenosis, especially for ECAS.

Triglyceride Glucose Index Associated With Arterial Stiffness in Chinese Community-Dwelling Elderly

Background: The population of older adults is growing rapidly with the increasing pace of aging worldwide. The triglyceride glucose (TyG) index has been a convenient and reliable surrogate marker of insulin resistance (IR). This study aimed to determine the association between the TyG index and arterial stiffness assessed by brachial-ankle pulse wave velocity (baPWV) in Chinese older adults.

Methods: A total of 2,035 participants aged 60 years or above were enrolled. Demographic, anthropometric, and cardiovascular risk factors were collected. TyG index was calculated using ln (fasting triglycerides [mg/dL] × fasting glucose [mg/dL]/2). Arterial stiffness was measured using baPWV.

Results: The participants, with the mean [standard deviation (SD)] age of 71.32 (6.75) years, the female proportion of 39.65%, the mean (SD) baPWV of 1,998 (437) cm/s, and the mean (SD) TyG index of 8.86 (0.54), were divided into four groups according to TyG index quartiles. Age-adjusted baPWV presented an increasing trend according to TyG index quartiles. In the fully adjusted linear regression model, the baPWV increased 49 cm/s, with the 95% confidence interval (CI) from 24 to 75 cm/s, per-SD increase in the TyG index. In the fully-adjusted logistic regression model, the odds ratio (95% CI) of high baPWV (>75th percentile) was 1.32 (1.09, 1.60) for each SD increase in the TyG index. The generalized additive model analysis also confirmed the significant association of the TyG index with baPWV and high baPWV.

Conclusion: The TyG index is significantly associated with arterial stiffness assessed by baPWV in Chinese older adults.

Insulin resistance, cardiovascular stiffening and cardiovascular disease

The cardiometabolic syndrome (CMS) and obesity are typically characterized by a state of metabolic insulin resistance. As global and US rates of obesity increase there is an acceleration of the incidence and prevalence of insulin resistance along with associated cardiovascular disease (CVD). Under physiological conditions insulin regulates glucose homeostasis by enhancing glucose disposal in insulin sensitive tissues while also regulating delivery of nutrients through its vasodilation actions on small feed arteries. Specifically, insulin-mediated production of nitric oxide (NO) from the vascular endothelium leads to increased blood flow enhancing disposal of glucose. Typically, insulin resistance is considered as a decrease in sensitivity or responsiveness to the metabolic actions of insulin including insulin-mediated glucose disposal. However, a decreased sensitivity to the normal vascular actions of insulin, especially diminished nitric oxide production, plays an additional important role in the development of CVD in states of insulin resistance. One mechanism by which insulin resistance and attendant hyperinsulinemia promote CVD is via increases in vascular stiffness. Although obesity and insulin resistance are known to be associated with substantial increases in the prevalence of vascular fibrosis and stiffness the mechanisms and mediators that underlie vascular stiffening in insulin resistant states are complex and have only recently begun to be addressed. Current evidence supports the role of increased plasma levels of aldosterone and insulin and attendant reductions in bioavailable NO in the pathogenesis of impaired vascular relaxation and vascular stiffness in the CMS and obesity. Aldosterone and insulin both increase the activity of serum and glucocorticoid kinase 1 (SGK-1) which in turn is a major regulator of vascular and renal sodium (Na⁺⁾ channel activity.The importance of SGK-1 in the pathogenesis of the CMS is highlighted by observations that gain of function mutations in SGK-1 in humans promotes hypertension, insulin resistance and obesity. In endothelial cells, an increase in Na⁺ flux contributes to remodeling of the cytoskeleton, reduced NO bioavailability and vascular stiffening. Thus, endothelial SGK-1 may represent a point of convergence for insulin and aldosterone signaling in arterial stiffness associated with obesity and the CMS. This review examines our contemporary understanding of the link between insulin resistance and increased vascular stiffness with emphasis placed on a role for enhanced SGK-1 signaling as a key node in this pathological process.

Blood Pressure and Body Weight Have Different Effects on Pulse Wave Velocity and Cardiac Mass in Children

Background: High blood pressure (BP) and excess weight can lead to early cardiovascular organ damage already in children. Carotid-femoral pulse wave velocity (cf-PWV) is the non-invasive gold standard method for assessing aortic stiffness, while carotid-radial PWV (cr-PWV) provides information on the distensibility of the upper limb arteries. The aim of this study was to evaluate the relationship of BP and BMI z-scores with arterial stiffness and left ventricular mass index (LVMI) in a pediatric population. Methods: In 343 children (57.7% males; age ± SD 11.7 ± 2.9 years), systolic (SBP) and diastolic (DBP) BP, BMI, cf-PWV, cr-PWV and LVMI were measured. A multiple linear regression model was used to assess the impact of BMI and SBP (or DBP) z-scores on cf-PWV, cr-PWV and LVMI. Results: About 21% of children were normal weight, 34% were overweight and 45% obese. Adjusted for possible confounders, SBP and DBP z-scores were significantly associated with cf-PWV (p < 0.001), while only DBP z-scores were related to cr-PWV (p < 0.01). BMI was neither associated with cf-PWV nor with cr-PWV values but was a strong predictor of LVMI (<0.001), whereas cardiac mass and BP z-scores were not related. Conclusions: Our study suggests that, in children, elevated BP values and excess weight may have different effects on the heart and the vessels in causing early cardiovascular alterations.

Depressive symptoms, its sub-factors, and augmentation index: the modifying effects according to inflammatory markers

Background This study aimed to investigate the association between depression and the augmentation index (AIx), and to further investigate whether there is a difference in this association according to the patients' inflammatory status. Methods This study included 458 men and 815 women (mean age: 49.35 years), a community-dwelling and middle-aged Korean population. The Korean version of the Beck Depression Inventory-II (BDI-II) was used to assess depressive symptoms. Arterial stiffness was evaluated via an AIx normalized to 75 beats/min. We confirmed two factors from BDI-II after conducting a factor analysis. Multiple regression models were used after adjusting for socio-demographic factors, lifestyle factors, systolic blood pressure, diabetes history, and body mass index. We further stratified the data according to inflammatory biomarkers with cutoffs of the 75^th percentile. Results There was a significant positive association between the BDI-II score and arterial stiffness (ß= 0.09, p-value=0.037). In women, the somatic-affective factor showed a stronger positive association (ß= 0.20, p-value=0.018) with arterial stiffness than the cognitive factor (ß= 0.12, p-value=0.148). There was no significant association in men (ß= -0.01, p-value=0.943). In subgroup analyses, women showed significant positive associations between the somatic affective factor of depressive symptoms on and arterial stiffness according to both inflammatory markers (IL-6: ß= 0.17, p-value=0.039; hs-CRP: ß= 0.17, p-value=0.094) Limitations The design of the cross-sectional study limits causal interpretation. Conclusion Depression and its somatic-affective factor were positively associated with arterial stiffness in women. Inflammatory status may be involved in modifying the association between depressive symptoms, its sub-factors, and AIx.

Association of obesity with arterial stiffness: The Multi-Ethnic Study of Atherosclerosis (MESA)

Arterial stiffness (AS) and obesity are recognized as important risk factors of cardiovascular disease (CVD). The purpose of this study was to investigate the relationship between AS and obesity. AS was defined as high augmentation index (AIx) and low elasticity (C1, large artery elasticity; C2, small artery elasticity) in participants enrolled in the Multi-Ethnic Study of Atherosclerosis at baseline. We compared AIx, C1, and C2 by body mass index (BMI) (< 25, 25-29.9, 30-39.9, ⩾ 40 kg/m²) and waist-hip ratio (WHR) (< 0.85, 0.85-0.99, ⩾ 1). The obesity-AS association was tested across 10-year age intervals. Among 6177 participants (62 ± 10 years old, 52% female), a significant inverse relationship was observed between obesity and AS. After adjustments for CVD risk factors, participants with a BMI > 40 kg/m² had 5.4% lower AIx (mean difference [Δ] = -0.82%; 95% CI: -1.10, -0.53), 15.4% higher C1 (Δ = 1.66 mL/mmHg ×10; 95% CI: 1.00, 2.33), and 40.2% higher C2 (Δ = 1.49 mL/mmHg ×100; 95% CI: 1.15, 1.83) compared to those with a BMI < 25 kg/m² (all p for trend < 0.001). Participants with a WHR ⩾ 1 had 5.6% higher C1 (∆ = 0.92 mL/mmHg ×10; 95% CI: 0.47, 1.37) compared to those with a WHR < 0.85. The WHR had a significant interaction with age on AIx and C2, but not with BMI; the inverse relationships of the WHR with AIx and C2 were observed only in participants < 55 years between the normal (WHR < 0.85) and the overweight (0.85 ⩽ WHR < 0.99) groups. Different associations of WHR and BMI with arterial stiffness among older adults should be further investigated.

The Effects of Mat Pilates Training on Vascular Function and Body Fatness in Obese Young Women With Elevated Blood Pressure

BACKGROUND

Effective nonpharmacological interventions targeting the enhancement of vascular function and decline of body fatness (BF) in obese individuals are indispensable for the prevention of hypertension and cardiovascular events in young adults. Mat Pilates training (MPT) has gained significant popularity worldwide, yet its effects on vascular function and body composition are understudied. We examined the effects of MPT on vascular function and BF in young obese women with elevated blood pressure (BP).

METHODS

Twenty-eight young obese women with elevated BP were randomized to an MPT (n = 14) or a nonexercising control (CON, n = 14) group for 12 weeks. Systemic arterial stiffness (brachial-ankle pulse wave velocity (baPWV)), brachial and aortic BP, wave reflection (augmentation index (AIx)), plasma nitric oxide (NO) levels, and BF percentage (BF%) were assessed before and after 12 weeks.

RESULTS

MPT significantly reduced (P ˂ 0.05) baPWV (-0.7 ± 0.2 m/s), AIx (-4 ± 1%), brachial systolic BP (-5 ± 1 mm Hg), aortic systolic BP (-6 ± 1 mm Hg), and BF% (-2 ± 1%), while significantly increasing plasma NO (6 ± 2 µM) (P ˂ 0.05) compared with CON. MPT improved systemic arterial stiffness, aortic BP, wave reflection, circulating plasma NO, and BF% in young obese women with elevated BP.

CONCLUSIONS

MPT may be an effective intervention for the improvement of vascular function and BF in young obese women with elevated BP, a population at risk for hypertension and early vascular complications.

CLINICAL TRIALS REGISTRATION

Trial Number NCT03907384.

WHOLE-BODY VIBRATION TRAINING PROTOCOLS IN OBESE INDIVIDUALS: A SYSTEMATIC REVIEW

ABSTRACT Obesity is a chronic degenerative disease. Whole-body vibration (WBV) devices make it possible to control the intensity of exercises through their variables: frequency, amplitude and vibration time, thus enabling interventions in these populations. The objective of this study was to review the applications, protocols and results of WBV devices in obese individuals. A systematic literature review was conducted using the descriptors and terms verified in DeCS (LILACS and SCIELO) and MeSH (PubMED). Of the thirteen studies selected, seven used an experimental and six a quasi-experimental methodological design. Eleven studies analyzed chronic responses and two studies acute responses to WBV training. Frequency values ranged between 30 and 35 Hz, amplitude was around 2 mm, and in terms of intensity, most of the training protocols used a gradual increase in WBV throughout the intervention. Eight studies added dynamic exercises and extra loads to the WBV. The mean total WBV exposure time varied around 20’ distributed in 1 or 2 series, with vibration times of 30” to 60” and the same rest time. The mean frequency of interventions was around 2 to 3 times a week, with a mean intervention time of 10 months. The main results include: decrease in body weight and improvement in the physiological variables of oxygen absorption, bone mineral density and arterial profile, indicating that WBV can be a safe tool in the fight against obesity and its implications. Level of Evidence II. Systematic Review of Level II Studies.

The radial augmentation index in children with Kawasaki disease without acute coronary artery lesions during the convalescent period

Purpose

We recently reported that children and adolescents with a history of Kawasaki disease (KD) had slight but significant elastic arterial stiffness even when no coronary artery lesions (CALs) were present. Moreover, we hypothesized that KD-related arteriopathy may also cause peripheral artery dysfunction. The objective of this study was to assess the involvement of radial artery pulse waves, especially reflection waves from the peripheral arteries using the radial artery augmentation index (rAI) in patients without CALs after KD.

Materials and methods

We first collected the rAI data from 312 subjects (149 consecutive patients of KD and 163 control subjects). Next, 225 cases between 6 and 15 years old were selected. Finally, 41 pairs were included for analysis. The rAI values of these two groups were compared and analyzed. Acute-phase data were also collected to reveal the possible correlation with rAI in the convalescent period.

Results

Multivariable analysis revealed the history of KD was positively correlated with rAI@75 value in children from 6 to 15 years old. After pairing the height and gender, the KD group also had significantly higher rAI and rAI@75 than the control group (rAI 60.63±13.77 vs 54.56±13.17, p=0.028; rAI@75 63.61±15.21 vs 55.68±14.86, p=0.003). With regard to acute-phase condition, nonresponse to initial treatment was also linked to elevated rAI during the convalescent period.

Conclusions

During the convalescent period, the rAI increased in KD patients without acute CALs. Furthermore, nonresponse to initial treatment in acute phase conferred higher rAI to KD subjects than respondent cases. Elevated rAI means the reflection wave from the peripheral vascular is stronger or earlier. This small but significant change may indicate the existence of peripheral artery stiffness during the convalescent period.

Predictors and Consequences of Pediatric Hypertension: Have Advanced Echocardiography and Vascular Testing Arrived?

PURPOSE OF REVIEW

Pediatric hypertension is relatively common and associated with future adult hypertension. Elevated blood pressure in youth predicts future adult cardiovascular disease and blood pressure control can prevent progression of pediatric kidney disease. However, pediatric blood pressure is highly variable within a given child and among children in a population.

RECENT FINDINGS

Therefore, modalities to index aggregate and cumulative blood pressure status are of potential benefit in identifying youth in danger of progression from a risk factor of subclinical phenotypic alteration to clinically apparent event. In this review, we advocate for the health risk stratification roles of echocardiographically assessed cardiac remodeling, arterial stiffness assessment, and assessment by ultrasound of arterial thickening in children and adolescents with hypertension.

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.

Early Life Adversity with Height Stunting Is Associated with Cardiometabolic Risk in Adolescents Independent of Body Mass Index

OBJECTIVE

To evaluate cardiovascular and metabolic function in youths adopted internationally from orphanages/institutions (postinstitutionalized) who were height-stunted at adoption.

STUDY DESIGN

A total of 30 postinstitutionalized youths (age, 9-18 years; body mass index [BMI] percentile, 7.2-90.4) who were height-stunted at adoption were compared with age- and BMI percentile-matched youths (n = 90). Measurements included total body fat and visceral adipose tissue (dual radiograph absorptiometry), arterial stiffness (augmentation index and pulse wave velocity), cardiac autonomic function (heart rate variability), blood pressure, and fasting lipid, glucose, and insulin levels. Linear regression analyses were computed controlling for parent education, age, trunk tissue fat, height-for-age, sex, and race.

RESULTS

Compared with controls of the same age, sex, and BMI, the postinstitutionalized children had higher systolic blood pressure (P = .018), augmentation index (P= .033), total cholesterol (P= .047), low-density lipoprotein cholesterol (P= .03), triglycerides (P= .048), insulin (P= .005), and HOMA-IR (P= .01) values. The postinstitutionalized children had a lower low-frequency to high-frequency ratio (P = .008), indicating lower sympathetic tone, as well as a lower total lean mass (P = .016), a lower gynoid lean mass (P = .039), and a higher proportion of trunk tissue fat (P = .017). The postinstitutionalized and control children did not differ in any other body composition measures.

CONCLUSIONS

Early life stress, as represented by height-stunted growth in institutional care, may be associated with early pathways to cardiovascular and metabolic risk in youths even after moving into well-resourced homes early in life and in the absence of increased adiposity. These findings suggest that postinstitutionalized youths with a history of height stunting may need to be closely monitored for emergent cardiometabolic risk factors.

Effects of a Short-Term Recreational Team Handball-Based Programme on Physical Fitness and Cardiovascular and Metabolic Health of 33-55-Year-Old Men: A Pilot Study

Recreational team handball is an intermittent high-intensity exercise mode with physiological demands in the range of those found to enhance health and physical fitness of sedentary adults. We examined the effects of a short-term team handball-based training programme on physical fitness and metabolic and cardiovascular health of sedentary 33-55-year-old former male team handball players. Twenty-four participants were divided into team handball (THG; n=15) and control groups (CG; n=9) and evaluated at baseline and postintervention. During 12 weeks, THG performed 2-3 60-min recreational team handball matches weekly (average: 2.2 ± 0.7), and CG maintained an inactive lifestyle. Average heart rate (HR) during matches was 80 ± 7%HRmax, with peak values of 91 ± 6%HRmax. A time-by-group interaction was shown in aerobic performance (p=0.016), postural balance (p=0.019), maximum oxygen uptake (VO2max) (p=0.023), resting HR (p<0.001), high-density lipoprotein (HDL) cholesterol (p=0.048), and fasting blood glucose (p=0.052) in favor of THG. THG improved aerobic performance (80%, p<0.001), VO2max (14%, p<0.001), and postural balance (27%, p=0.018). Decreases in resting HR (16%, p<0.001) and fasting blood glucose (7%, p=0.015) and increases in HDL cholesterol (11%, p=0.002) were found in THG. Recreational team handball practice shows positive physical fitness and health-related adaptations, with high attendance, which may contribute to the reduction of the risk of developing lifestyle diseases.

Brachial artery stiffening in healthy primigravidas is associated with weight gain and increased cardiac output

OBJECTIVE

To assess brachial artery distensibility and associated factors in healthy primigravidas.

METHODS

We assessed brachial artery distensibility using the DynaPulse 5,000A in 37 women each trimester, and 6-8 weeks and 1-5 years postpartum. Associations with physical and cardiometabolic measures were considered.

RESULTS

Mean (SE) brachial artery distensibility (%Δ/mmHg) decreased (stiffened) from 7.50 (0.20) 12-14 weeks to 6.93 (0.22) 36-38 weeks (p < .01) and returned to baseline 7.52 (0.44) at 2.7 years postpartum. Weight gain and greater cardiac output were significantly related to greater stiffness.

CONCLUSION

Increased weight and cardiac output of pregnancy were associated with brachial artery stiffening.

Pulse wave analyzed cardiovascular parameters in young first degree relatives of hypertensives

Background:

First-degree relatives (FDRs) of hypertensive (HT) are predisposed to hypertension (HTN) which accelerates cardiovascular aging. Same can be studied noninvasively by pulse wave analysis (PWA), encompassing central hemodynamics such as central blood pressure (cBP), cardiac output, and stroke work (SW) and vascular stiffness parameters such as pulse wave velocity (PWV) and augmentation index at HR 75 (AIx@75). We studied PWA-derived cardiovascular parameters in FDRs of HT compared to controls.

Materials and Methods:

We conducted a case–control study in 119 FDRs of HT and 119 matched controls. Oscillometric PWA was performed by Mobil-o-Graph (IEM, Germany) and cardiovascular parameters were compared. P < 0.05 was considered statistically significant.

Results:

Groups were comparable with gender, age, height, weight, body mass index, and physical activity. FDRs of HT had significantly higher brachial and cBPs, SW (101.41 ± 25.44 vs. 88.31 ± 20.25, P = 0.001), rate pressure product-119.40 ± 25.34 vs. 108.34 ± 18.17, P < 0.0001), PWV (5.22 ± 0.46, P < 0.0001), and AIx@75 (31.48 ± 9.01 vs. 27.95 ± 9.4, P = 0.002) than control. Dependent study variables correlated with brachial blood pressure more in magnitude and significance level than age or anthropometric variables. PWA results of FDR with maternal inheritance did not differ significantly from those with paternal inheritance.

Conclusion:

PWA reveals early cardiovascular aging in young FDRs of HTs. It clues to future cardiovascular disease including HTN itself, need for primary prevention, and further study for consolidation of these results.

Clinical Implications of the Revised AAP Pediatric Hypertension Guidelines

BACKGROUND AND OBJECTIVES

New pediatric hypertension definitions were recently published in a clinical practice guideline (CPG). We evaluated the impact of the CPG, compared with the previous guideline ("Fourth Report on the Diagnosis, Evaluation, and Treatment of High Blood Pressure in Children and Adolescents"), on the prevalence of hypertension and associations with target organ damage (TOD) in high-risk youth.

METHODS

Participants (10-18 years old) undergoing an evaluation of the cardiovascular effects of obesity and type 2 diabetes mellitus in youth were studied. Blood pressure was categorized according to the 2 guidelines as normal, elevated, and hypertension (stages 1 and 2). Measures of TOD (carotid artery intima-media thickness, pulse wave velocity, left ventricular mass, and diastolic function) were obtained. Associations between blood pressure categories and TOD and the sensitivity of hypertension classification in identifying TOD were evaluated.

RESULTS

Data were available for 364 participants (65% female sex; 15.1 ± 2.1 years of age). Hypertension was identified in 8% and 13% as defined in the Fourth Report and CPG, respectively (P = .007). The 2 guidelines revealed similar associations with TOD; however, the CPG demonstrated improved sensitivity of TOD detection in hypertensive participants. For example, the proportion of participants with an abnormal left ventricular mass categorized as hypertensive increased from 20% to 31% as defined in the Fourth Report and CPG, respectively (P < .001).

CONCLUSIONS

Incorporation of the CPG increased the prevalence of pediatric hypertension in a population of high-risk youth and improved the sensitivity of TOD identification in hypertensive participants.

Inappropriate Use of Homeostasis Model Assessment Cutoff Values for Diagnosing Insulin Resistance in Pediatric Studies

Background

Assessing pediatric patients for insulin resistance is one way to identify those who are at a high risk of developing type 2 diabetes mellitus. The homoeostasis model assessment (HOMA) is a measure of insulin resistance based on fasting blood glucose and insulin levels. Although this measure is widely used in research, cutoff values for pediatric populations have not been established.

Objective

To assess the validity of HOMA cutoff values used in pediatric studies published in peer-reviewed journals.

Methods

Studies published from January 2010 to December 2015 were identified through MEDLINE. Initial screening of abstracts was done to select studies that were conducted in pediatric populations and used HOMA to assess insulin resistance. Subsequent full-text review narrowed the list to only those studies that used a specific HOMA score to diagnose insulin resistance. Each study was classified as using a predetermined fixed HOMA cutoff value or a cutoff that was a percentile specific to that population. For studies that used a predetermined cutoff value, the references cited to provide evidence in support of that cutoff were evaluated.

Results

In the 298 articles analyzed, 51 different HOMA cutoff values were used to classify patients as having insulin resistance. Two hundred fifty-five studies (85.6%) used a predetermined fixed cutoff value, but only 72 (28.2%) of those studies provided a reference that supported its use. One hundred ten studies (43%) that used a fixed cutoff either cited a study that did not mention HOMA or provided no reference at all. Tracing of citation history indicated that the most commonly used cutoff values were ultimately based on studies that did not validate their use for defining insulin resistance.

Conclusion

Little evidence exists to support HOMA cutoff values commonly used to define insulin resistance in pediatric studies. These findings highlight the importance of validating study design elements when training medical students and novice investigators. Using available data to generate population ranges for HOMA would improve its clinical utility.

New insights into arterial stiffening: does sex matter?

This review discusses sexual dimorphism in arterial stiffening, disease pathology interactions, and the influence of sex on mechanisms and pathways. Arterial stiffness predicts cardiovascular mortality independent of blood pressure. Patients with increased arterial stiffness have a 48% higher risk for developing cardiovascular disease. Like other cardiovascular pathologies, arterial stiffness is sexually dimorphic. Young women have lower stiffness than aged-matched men, but this sex difference reverses during normal aging. Estrogen therapy does not attenuate progressive stiffening in postmenopausal women, indicating that currently prescribed drugs do not confer protection. Although remodeling of large arteries is a protective adaptation to higher wall stress, arterial stiffening increases afterload to the left ventricle and transmits higher pulsatile pressure to smaller arteries and target organs. Moreover, an increase in aortic stiffness may precede or exacerbate hypertension, particularly during aging. Additional studies are needed to elucidate the mechanisms by which females are protected from arterial stiffness to provide insight into its mechanisms and, ultimately, therapeutic targets for treating this pathology.

Cardiac and Vascular Target Organ Damage in Pediatric Hypertension

Atherosclerosis begins in youth and is associated with the presence of numerous modifiable cardiovascular (CV) risk factors, including hypertension. Pediatric hypertension has increased in prevalence since the 1980s but has plateaued in recent years. Elevated blood pressure levels are associated with impairments to cardiac and vascular structure and both systolic and diastolic function. Blood pressure-related increases in left ventricular mass (LVM) and abnormalities in cardiac function are associated with hard CV events in adulthood. In addition to cardiac changes, key vascular changes occur in hypertensive youth and adults. These include thickening of the arteries, increased arterial stiffness, and decreased endothelial function. This review summarizes the epidemiologic burden of pediatric hypertension, its associations with target organ damage (TOD) of the cardiac and vascular systems, and the impact of these adverse CV changes on morbidity and mortality in adulthood.

Reference intervals and percentiles for carotid-femoral pulse wave velocity in a healthy population aged between 9 and 87 years

There is little information regarding age-related reference intervals (RIs) of carotid-femoral pulse wave velocity (cfPWV) for large healthy populations in South America. The aims of this study were to determine cfPWV RIs and percentiles in a cohort of healthy children, adolescents, and adults and to generate year-to-year percentile curves and body-height percentile curves for children and adolescents. cfPWV was measured in 1722 healthy participants with no cardiovascular risk factors (9-87 years, 60% men). First, RIs were evaluated for males and females through correlation and covariate analysis. Then, mean and standard deviation age-related equations were obtained for cfPWV using parametric regression methods based on fractional polynomials and age-specific (year-to-year) percentile curves that were defined using the standard normal distribution. Age-specific first, 2.5th, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97.5th, and 99th percentile curves were calculated. Finally, height-related cfPWV percentile curves for children and adolescents (<21 years) were established. After adjusting for age and blood pressure differences with respect to females, males showed higher cfPWV levels (6.60 vs 6.45 m/s; P < .01). Thus, specific RIs for males and females were reported. The study provides the largest database to date concerning cfPWV in healthy people from Argentina. Specific RIs and percentiles of cfPWV are now available according to age and sex. Specific percentiles of cfPWV according to body height were reported for people younger than 21 years.

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.

Perceived neighborhood safety related to physical activity but not recreational screen-based sedentary behavior in adolescents

BACKGROUND

A growing proportion of adolescents have poor cardiovascular health behaviors, including low levels of physical activity and high levels of sedentary behavior, thus increasing the likelihood of poor heart health in later years. This study tested the hypothesis that low perceived neighborhood safety would be associated with low levels of physical activity and high levels of recreational sedentary behavior in high-school students.

METHODS

Using cross-sectional, weighted data from the 2015 Pennsylvania (USA) State and Philadelphia city Youth Risk Behavior Survey, multivariable logistic regression modeling was used to examine the association between perceived neighborhood safety, and physical activity levels and recreational screen-based sedentary behavior time respectively, while controlling for potential confounders.

RESULTS

After adjustment for other significant correlates of physical activity, students with low perceived neighborhood safety had a 21% reduced odds of being physically active on 5 or more days of the last week as compared to those who felt safe (p = 0.044). Perceived safety was not related to sedentary behavior; but sports team participation emerged as a strong correlate of low screen-based sedentary behavior (OR = 0.73, p = .002).

CONCLUSION

These data add to a growing body of work demonstrating the importance of perceived safety with physical activity levels in youth. Sports team participation may be a viable target to reduce screen-based sedentary time.

Suicidal Ideation Is Associated with Altered Variability of Fingertip Photo-Plethysmogram Signal in Depressed Patients

Physiological and psychological underpinnings of suicidal behavior remain ill-defined and lessen timely diagnostic identification of this subgroup of patients. Arterial stiffness is associated with autonomic dysregulation and may be linked to major depressive disorder (MDD). The aim of this study was to investigate the association between arterial stiffness by photo-plethysmogram (PPG) in MDD with and without suicidal ideation (SI) by applying multiscale tone entropy (T-E) variability analysis. Sixty-one 10-min PPG recordings were analyzed from 29 control, 16 MDD patients with (MDDSI+) and 16 patients without SI (MDDSI-). MDD was based on a psychiatric evaluation and the Mini-International Neuropsychiatric Interview (MINI). Severity of depression was assessed using the Hamilton Depression Rating Scale (HAM-D). PPG features included peak (systole), trough (diastole), pulse wave amplitude (PWA), pulse transit time (PTT) and pulse wave velocity (PWV). Tone (Diastole) at all lags and Tone (PWA) at lags 8, 9, and 10 were found to be significantly different between the MDDSI+ and MDDSI- group. However, Tone (PWA) at all lags and Tone (PTT) at scales 3-10 were also significantly different between the MDDSI+ and CONT group. In contrast, Entropy (Systole), Entropy (Diastole) and Tone (Diastole) were significantly different between MDDSI- and CONT groups. The suicidal score was also positively correlated (r = 0.39 ~ 0.47; p < 0.05) with systolic and diastolic entropy values at lags 2-10. Multivariate logistic regression analysis and leave-one-out cross-validation were performed to study the effectiveness of multi-lag T-E features in predicting SI risk. The accuracy of predicting SI was 93.33% in classifying MDDSI+ and MDDSI- with diastolic T-E and lag between 2 and 10. After including anthropometric variables (Age, body mass index, and Waist Circumference), that accuracy increased to 96.67% for MDDSI+/- classification. Our findings suggest that tone-entropy based PPG variability can be used as an additional accurate diagnostic tool for patients with depression to identify SI.

Central Arterial Function Measured by Non-invasive Pulse Wave Analysis is Abnormal in Patients with Duchenne Muscular Dystrophy

Duchenne muscular dystrophy (DMD) is an X-linked recessive disorder caused by mutation of dystrophin. Cardiovascular involvement includes dilated cardiomyopathy. Non-invasive assessment of vascular function has not been evaluated in DMD. We hypothesize arterial wave reflection is abnormal in patients with DMD. Pulse wave analysis was performed on DMD patients with a SphygmoCor SCOR-PVx System to determine central blood pressure and augmentation index (AIx) as an assessment of arterial wave reflection. Results were compared to a control group. A total of 43 patients with DMD were enrolled, and compared to 43 normal controls. Central systolic blood pressure was lower, while both AIx-75 (7.8 ± 9.6% vs. 2.1 ± 10.4%, p 0.01, DMD vs. normal) and AIx-not corrected (16.8 ± 10.1% vs. -3.6 ± 10.9, p < 0.001, DMD vs. normal) were higher in the DMD compared to control. Using multivariable linear regression model, the variables found to have a significant effect on AIx-not corrected included diagnosis of DMD, height, and heart rate (r ² = 0.257). The current data suggest that, despite lower central systolic blood pressure, patients with DMD have higher wave reflection when compared to normal controls, which may represent increased arterial stiffness. Overall there appears to be no effect on ventricular systolic function, however the long-term consequence in this group is unknown. Further study is required to determine the mechanism of these differences, which may be related to the effects of systemic steroids or the role of dystrophin in vascular function.

Cardiometabolic Determinants of Carotid and Aortic Distensibility From Childhood to Early Adulthood

Children who are obese or have familial hypercholesterolemia have stiffer arteries compared with lean, healthy peers. Limited data are, however, available on the association of cardiometabolic risk markers and arterial distensibility in healthy children, particularly in a longitudinal setting. Therefore, we studied in the prospective STRIP (Special Turku Coronary Risk Factor Intervention Project) comprising healthy, predominantly normal weight participants the association of several cardiometabolic and dietary risk markers with arterial distensibility from childhood to early adulthood. Carotid and aortic distensibility (cdist, adist) was assessed repeatedly with ultrasonography at the age of 11, 13, 15, 17, and 19 years in the longitudinal atherosclerosis prevention study (n_cdist=420-503, n_adist=407-476). Data on cardiometabolic risk markers and diet were available since early childhood. In multivariable analyses, body mass index (β=-0.0019 [SE 0.0085]; P=0.037), systolic blood pressure (β=-0.0025 [SE 0.00065]; P=0.0001), low-density lipoprotein cholesterol (β=-0.026 [SE 0.012]; P=0.034), and homeostasis model of insulin resistance (β=-0.048 [SE 0.018]; P=0.0071) were independently associated with carotid distensibility. Systolic blood pressure (β=-0.0069 [SE 0.00097]; P<0.0001) and low-density lipoprotein cholesterol (β=-0.039 [SE 0.018]; P=0.031) associated independently with aortic distensibility. Dietary variables were not independently associated with arterial distensibility. Participants with low arterial distensibility had higher body mass index (P_cdist=0.0090, P_adist=0.098) and higher systolic (P_cdist<0.0001, P_adist<0.0001) and diastolic blood pressures (P_cdist<0.0001, P_adist=0.0002) already from early childhood. Body mass index, blood pressure, low-density lipoprotein cholesterol, and homeostasis model of insulin resistance identified since childhood associate with arterial distensibility in healthy children and adolescents. These data support the relevance of these factors as part of primordial prevention.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00223600.

Combined exercise training reduces blood pressure, arterial stiffness, and insulin resistance in obese prehypertensive adolescent girls

Childhood obesity is strongly linked to pathological processes for cardiovascular diseases in later adulthood. Obese adolescent girls with high blood pressure (BP) are reported to have increased arterial stiffness, which is associated with the development of hypertension and atherosclerosis. The present study sought to examine the impact of combined resistance and aerobic exercise (CRAE) training on BP, brachial-ankle pulse wave velocity (baPWV), insulin resistance (IR), and body composition in obese prehypertensive girls. Forty girls (age, 15 ± 1 years; systolic BP, 132 ± 2 mmHg, diastolic BP, 80 ± 5 mmHg) were randomly assigned to either a combined exercise (EX, n = 20) or no exercise group (CON, n = 20). The EX group performed CRAE for 12 weeks, 3 times per week. BP, baPWV, blood nitrite/nitrate, endothelin-1 (ET-1), homeostasis model assessment for insulin resistance (HOMA-IR), and body composition were measured before and after the exercise intervention. BP (∆-7.3 ± 2.67 mmHg), baPWV (∆-1.23 ± 0.49 m/s), ET-1 (∆-14.35 ± 1.76 μmol/mL), nitrite/nitrate (∆0.5 ± 0.09 μM), HOMA-IR (∆-1.4 ± 0.07), percent body fat (∆-1.35 ± 0.9%), and waist circumference were significantly improved (P < 0.05) in the EX group after 12 weeks of training versus the CON group. These findings indicate that 12 weeks of CRAE improves BP, HOMA-IR, and arterial stiffness and reduces central adiposity in obese adolescent girls with prehypertension. Thus, this study provides evidence that CRAE can be a useful therapeutic treatment for high BP, IR, and central adiposity, thereby reducing the likelihood of pathological development for cardiovascular diseases in later adulthood.

Arterial stiffness and its association with clustering of metabolic syndrome risk factors

BACKGROUND

Metabolic syndrome (MetS) is associated with structural and functional vascular abnormalities, which may lead to increased arterial stiffness, more frequent cardiovascular events and higher mortality. However, the role played by clustering of risk factors and the combining pattern of MetS risk factors and their association with the arterial stiffness have yet to be fully understood. Age, hypertension and diabetes mellitus seem to be strongly associated with increased pulse wave velocity (PWV). This study aimed at determining the clustering and combining pattern of MetS risk factors and their association with the arterial stiffness in non-diabetic and non-hypertensive patients.

METHODS

Recently diagnosed and untreated patients with MetS (n = 64, 49 ± 8 year, 32 ± 4 kg/m²) were selected, according to ATP III criteria and compared to a control group (Control, n = 17, 49 ± 6 year, 27 ± 2 kg/m²). Arterial stiffness was evaluated by PWV in the carotid-femoral segment. Patients were categorized and analyzed according MetS risk factors clustering (3, 4 and 5 factors) and its combinations.

RESULTS

Patients with MetS had increased PWV when compared to Control (7.8 ± 1.1 vs. 7.0 ± 0.5 m/s, p < 0.001). In multivariate analysis, the variables that remained as predictors of PWV were age (β = 0.450, p < 0.001), systolic blood pressure (β = 0.211, p = 0.023) and triglycerides (β = 0.212, p = 0.037). The increased number of risk factors reflected in a progressive increase in PWV. When adjusted to systolic blood pressure, PWV was greater in the group with 5 risk factors when compared to the group with 3 risk factors and Control (8.5 ± 0.4 vs. 7.5 ± 0.2, p = 0.011 and 7.2 ± 0.3 m/s, p = 0.012). Similarly, the 4 risk factors group had higher PWV than the Control (7.9 ± 0.2 vs. 7.2 ± 0.3, p = 0.047).

CONCLUSIONS

The number of risk factors seems to increase arterial stiffness. Notably, besides age and increased systolic blood pressure, alterations in the triglycerides worsened the stiffness of large vessels, emphasizing the importance in addressing this risk factor in MetS patients.

Arterial Stiffness, Thickness and Association to Suitable Novel Markers of Risk at the Origin of Cardiovascular Disease in Obese Children

Atherosclerosis origins early in childhood. Aim of the study was to investigate vascular signature and phenotypes of cardiovascular disease in obese children and adolescents identifying novel potential circulating markers of risk. Cross-sectional study of intima-media-thickness (IMT), pulse wave velocity (PWV), augmentation index (AIX@75), circulating markers (E-selectin, soluble-intercellular-adhesion-molecule1_ICAM1, chemerin, fatty-acid-binding protein 4, sCD36, lipopolysaccharides_LPS, oxLDL, fetuin) in 123 obese (body mass index, BMI z-score >1.645 SD) children (N=55, age ≤10 years-old) and adolescents (N=68, age >10 years-old). Adolescents had significantly higher uric acid (p=0.002), non-HDL-cholesterol (p=0.02), fasting glucose (p=0.04), systolic blood pressure (p=0.005) and PWV (p=0.02) than children. Obese adolescent patients with metabolic syndrome (MetS) abnormalities had higher PWV (p<0.05) than peers without. No differences were observed in circulating biomarkers in relationship to age and MetS status. oxLDL, sCD36 and LPS were correlated to AIX@75 and/or IMT_M in children and adolescents (p ranging from <0.05 to <0.0001). Total cholesterol, non-HDL-cholesterol, TG/HDL ratio, oxLDL, sCD36, ICAM1, LPS were significantly different across AIX@75 tertiles (p between 0.03 and 0.001). Early phenotypes of cardiovascular alterations in young severely obese patients encompass increased IMT, stiffness of intermediate size and resistance vasculature. Novel biomarkers investigated in the present study were associated to estimates of stiffness and thickness not differently from traditional risk factor such as non-HDL-cholesterol and TG/HDL ratio.

Effects of Low versus High Glycemic Index Sugar-Sweetened Beverages on Postprandial Vasodilatation and Inactivity-Induced Impairment of Glucose Metabolism in Healthy Men

Intake of sugar-sweetened beverages (SSB) may contribute to cardiovascular risk. The aim of this study was to investigate whether functional sugars with low compared to high glycemic index (GI) have beneficial effects on arterial stiffness during a period of low-physical activity. In a controlled cross-over dietary intervention (55% CHO, 30% fat, 15% protein), 13 healthy men (age: 23.7 ± 2.2 years, body mass index: 23.6 ± 1.9 kg/m²) completed 2 × 1 week of low physical activity following 1 week of normal physical activity (2363 ± 900 vs. 11,375 ± 3124 steps/day). During inactive phases participants consumed either low-GI (isomaltulose) or high-GI SSB (maltodextrin-sucrose), providing 20% of energy requirements. Postprandial vasodilatation (augmentation index, AIx), insulin sensitivity (IS) and Glucagon-like-peptide 1 (GLP-1) responses were measured during a meal test before and after SSB-intervention. Compared to maltodextrin-sucrose-SSB, postprandial vasodilatation was prolonged (AIx after 120 min: 9.9% ± 4.3% vs. 11.4% ± 3.7%, p < 0.05) and GLP-1 secretion was higher with isomaltulose-SSB (total area under the GLP-1 curve (tAUCGLP)-1: 8.0 ± 4.4 vs. 5.4 ± 3.4 pM × 3 h; p < 0.05). One week of low-physical activity led to impaired IS that was attenuated with low-GI SSB consumption, but did not affect arterial stiffness (p > 0.05). Higher postprandial GLP-1 secretion after intake of low compared to high-GI beverages may contribute to improved postprandial vasodilatation. Although one week of low-physical activity led to marked impairment in IS, it had no effect on arterial stiffness in healthy men.

Abnormalities of vascular structure and function in pediatric hypertension

Hypertension is associated with adverse cardiovascular (CV) events in adults. Measures of vascular structure and function, including increased carotid intima-media thickness (cIMT) and elevated arterial stiffness predict hard CV events in adulthood. Newer data suggest that abnormalities in target organ damage are occurring in adolescents and young adults with high blood pressure. In this review, we discuss the techniques for measuring vascular dysfunction in young people and the evidence linking blood pressure levels to this type of target organ damage.

Determinants of carotid-femoral pulse wave velocity in prepubertal children

BACKGROUND

Pulse wave velocity (PWV) is a noninvasive technique to evaluate arterial stiffness, a dynamic property of the vessels, reflecting their structure and function. Childhood obesity is associated with several cardiovascular comorbidities and to the progression of atherosclerosis. We aimed to compare carotid-femoral PWV between normal weight and overweight/obese prepubertal children and to quantify its association with other cardiovascular risk factors.

METHODS

Cross-sectional study of 315 children aged 8-9years. Anthropometrics, 24-h ambulatory blood pressure (BP) and carotid-femoral PWV were measured. Classification of obesity was according to World Health Organization (WHO) body mass index (BMI)-for-age reference values.

RESULTS

Compared to normal weight children, overweight and obese children presented significantly higher levels of PWV (4.95 (P25-P75: 4.61-5.23), 5.00 (4.71-5.33), 5.10 (4.82-5.50) m/s, respectively; ptrend<0.001). Significant positive correlations were found between PWV and total cholesterol, LDL cholesterol, triglycerides, fasting insulin and insulin resistance levels (HOMA-IR) and with high-sensitivity C-reactive protein (hs-CRP). In a multivariate linear regression model adjusted for sex, age, height and 24-h systolic blood pressure z-score, the independent determinants of PWV were BMI, HOMA-IR and the absence of dipping.

CONCLUSIONS

The association between PWV and the loss of dipping and insulin resistance levels, independently of the BMI, reinforces the contribution of these comorbidities to vascular injury in early life.

Triglyceride to high-density lipoprotein cholesterol ratio and carotid intima-medial thickness in Chinese adolescents with newly diagnosed type 2 diabetes mellitus

OBJECTIVE

To investigate the relationship between triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio and carotid intima-medial thickness (CIMT) in Chinese youth and adolescents with newly diagnosed type 2 diabetes mellitus (T2DM).

METHODS

Ninety-eight subjects aged 10-24 yr with newly-diagnosed T2DM had general inflammation, anthropometric, laboratory and CIMT data collected, and were divided into three groups based on TG/HDL-C tertiles.

RESULTS

There were no significant differences in gender, age, fasting plasma glucose (FPG), hemoglobin A1c (HbA1c), and carotid arterial diameter (CAD) among the groups based on TG/HDL-C tertiles. Across TG/HDL-C tertiles, there was a significant progressive increase in body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), homeostasis model assessment-estimated insulin resistance (HOMA-IR), TG, total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C) and CIMT (all P < 0.01 or P < 0.05), while HDL-C was decreased significantly across the groups (P < 0.01). In general linear regression model, TG/HDL-C was an independent determinant of CIMT even after adjusting for BMI, SBP, DBP, TG, TC, LDL-C, HDL-C, HbA1c and HOMA-IR.

CONCLUSION

TG/HDL-C ratio, the marker of small dense LDL particles, is an independent determinant of CIMT in Chinese youth and adolescents with newly diagnosed T2DM, and may be a simple and helpful tool in predicting the increased CIMT in such patients.

Early Biomarkers of Subclinical Atherosclerosis in Obese Adolescent Girls with Polycystic Ovary Syndrome

OBJECTIVES

Because in obese youth, pulse wave velocity (PWV), an early cardiovascular disease marker, is elevated, we tested if obese girls with polycystic ovary syndrome (OB-PCOS) have higher PWV and carotid intima-media thickness (cIMT) compared with obese girls without PCOS (OB-non-PCOS) and normal-weight girls without PCOS (NW-non-PCOS) and whether PWV and cIMT correlate with inflammatory and circulating endothelial function biomarkers.

STUDY DESIGN

Cross-sectional study of PWV and cIMT in 91 OB-PCOS, 30 obese controls (OB-non-PCOS), and 19 normal-weight controls (NW-non-PCOS). Body composition, blood pressure, fasting glucose, insulin, lipid concentrations, and endothelial function biomarkers were measured. OB-non-PCOS and OB-PCOS underwent 2-hour oral glucose tolerance testing.

RESULTS

PWV was higher in OB-PCOS (664 ± 24 cm/s) and OB-non-PCOS (624 ± 37 cm/s) compared with NW-non-PCOS (468 ± 13 cm/s, P < .001), with no differences in cIMT. Systolic blood pressure, low-density lipoprotein, and non-high-density lipoprotein cholesterol were higher, and high-density lipoprotein cholesterol and indices of insulin sensitivity were lower in OB-PCOS and OB-non-PCOS compared with NW-non-PCOS. Vascular cell adhesion molecule-1 and high-sensitivity C-reactive protein were higher in OB-PCOS compared with NW-non-PCOS. PWV correlated with adiposity (rs = .46), insulin sensitivity index (homeostatic model assessment-insulin resistance rs = .31), systolic blood pressure (rs = .24; P ≤ .003 for all), and free testosterone (rs = .24; P = .03). In multiple regression analysis with PWV as the dependent variable and age, race, body mass index, PCOS, and dysglycemia as independent variables, only body mass index was an independent contributor to the model (r(2) = 0.068, P = .003).

CONCLUSIONS

In adolescent girls, obesity and not PCOS appears to be associated with heightened cardiovascular disease risk. Increased PWV, vascular cell adhesion molecule-1, and high-sensitivity C-reactive protein may be the earliest subclinical atherosclerosis biomarkers in OB-PCOS.

Low-Grade Inflammation and Increased Arterial Stiffness in Chinese Youth and Adolescents with Newly-Diagnosed Type 2 Diabetes Mellitus

OBJECTIVE

To investigate the relationship between low-grade inflammation (LI) and increased arterial stiffness in Chinese youth and adolescents with newly-diagnosed type 2 diabetes mellitus (T2DM).

METHODS

Ninety-eight subjects aged 10 to 24 years with newly-diagnosed T2DM were investigated for findings of general inflammation. Anthropometric measurements were taken. Data related to arterial stiffness [brachial artery distensibility (Branch D), augmentation index (AIx), carotid-femoral pulse wave velocity (CF-PWV)] were collected. The subjects were divided into a non-LI group (NLI, n=42) and a LI group (n=56) according to their high-sensitivity C-reactive protein (Hs-CRP) levels.

RESULTS

There were no significant differences in age and gender between the LI group and the NLI group. CF-PWV and AIx values of the LI group were higher than those of the NLI group (p<0.01), while Branch D values were lower in the LI group (p<0.01). Branch D, CF-PWV, and AIx values correlated significantly with Hs-CRP overall (r=-0.32, 0.34, 0.33, all p<0.01). Multivariate models revealed that in either group (LI or NLI), Hs-CRP, as a continuous variable, was an independent determinant of arterial stiffness parameters even after adjusting for other risk factors.

CONCLUSION

Newly-diagnosed T2DM youth and adolescents with LI present a more adverse cardiovascular disease risk profile and stiffer arteries. Hs-CRP levels correlated with arterial stiffness parameters and constituted an independent determinant of arterial stiffness.

Interrelationships between obesity, obstructive sleep apnea syndrome and cardiovascular risk in obese adolescents

BACKGROUND/OBJECTIVES

Obstructive sleep apnea syndrome (OSAS) may be a cardiovascular disease (CVD) risk factor independently of obesity in adults. Pediatric studies have associated OSAS with endothelial dysfunction, but few studies have examined relationships between OSAS and macrovascular sequelae. Our objective was to examine OSAS's independent contribution to macrovascular CVD risk measures in obese adolescents.

SUBJECTS/METHODS

This cross-sectional observational study was conducted at Children's Hospital of Philadelphia Clinical Research and Academic Sleep Centers, and University of Pennsylvania Vascular Research Unit. Thirty-one obese non-diabetic adolescents underwent anthropometric measurements, overnight polysomnography, fasting laboratory draw and cardiovascular imaging. Cardiovascular outcome measures included maximal carotid intima-media thickness (cIMTmax), a measure of carotid structural changes, and carotid-femoral pulse wave velocity (CFPWV), an aortic stiffness measure whose relationship vis-à-vis OSAS in children has not been previously examined. Carotid diameter and augmentation index (AIx, measuring central pressure augmentation from wave reflections) were assessed. Potential confounding variables examined included blood pressure, lipoproteins, high-sensitivity C-reactive protein, insulin and glucose.

RESULTS

The apnea hypopnea index, a primary OSAS measure, was not associated with cIMTmax, carotid diameter, CFPWV or AIx. body mass index (BMI) associated positively with cIMTmax (r=0.52, P=0.006) and CFPWV (r=0.45, P=0.01). Mean asleep end-tidal CO2 was negatively associated with carotid diameter (r=-0.63, P<0.0005). Insulin levels were negatively associated with AIx (r=-0.53, P=0.02).

CONCLUSIONS

OSAS did not predict carotid structural changes or arterial stiffness independently of BMI in obese adolescents. Higher insulin levels associated with lower central pressure wave augmentation. Finally, long-term hypercapnia may predispose to carotid narrowing.

Combined dyslipidemia in childhood

Combined dyslipidemia (CD) is now the predominant dyslipidemic pattern in childhood, characterized by moderate-to-severe elevation in triglycerides and non-high-density lipoprotein cholesterol (non-HDL-C), minimal elevation in low-density lipoprotein cholesterol (LDL-C), and reduced HDL-C. Nuclear magnetic resonance spectroscopy shows that the CD pattern is represented at the lipid subpopulation level as an increase in small, dense LDL and in overall LDL particle number plus a reduction in total HDL-C and large HDL particles, a highly atherogenic pattern. In youth, CD occurs almost exclusively with obesity and is highly prevalent, seen in more than 40% of obese adolescents. CD in childhood predicts pathologic evidence of atherosclerosis and vascular dysfunction in adolescence and young adulthood, and early clinical cardiovascular events in adult life. There is a tight connection between CD, visceral adiposity, insulin resistance, nonalcoholic fatty liver disease, and the metabolic syndrome, suggesting an integrated pathophysiological response to excessive weight gain. Weight loss, changes in dietary composition, and increases in physical activity have all been shown to improve CD significantly in children and adolescents in short-term studies. Most importantly, even small amounts of weight loss are associated with significant decreases in triglyceride levels and increases in HDL-C levels with improvement in lipid subpopulations. Diet change focused on limitation of simple carbohydrate intake with specific elimination of all sugar-sweetened beverages is very effective. Evidence-based recommendations for initiating diet and activity change are provided. Rarely, drug therapy is needed, and the evidence for drug treatment of CD in childhood is reviewed.

Insulin sensitivity and arterial stiffness in youth with type 1 diabetes: the SEARCH CVD study

AIMS

Decreased insulin sensitivity is a cardiovascular risk factor (CVRF) in youth with type 1 diabetes (T1D). Whether baseline insulin sensitivity is independently associated with changes in early arterial stiffness (pulse wave velocity (PWV)) over time in youth with T1D is not known.

METHODS

Two hundred ninety-eight youth with T1D in the SEARCH CVD study had PWV measured~five years apart. Insulin sensitivity and other CVRFs were measured at baseline. The association between baseline insulin sensitivity with PWV over time was explored using linear mixed models. Models were adjusted for baseline age, sex and race, with subsequent adjustment for CVRFs.

RESULTS

There was a significant interaction (p=0.0326) between baseline insulin sensitivity and time on PWV, independent of CVRFs, indicating that higher insulin sensitivity levels were associated with lower rate of change in PWV over time. Other significant predictors of PWV change were baseline age [β=0.007 (p=0.03) increase in logPWV/year increase in age] and mean arterial blood pressure (MAP) [β=0.005 (p<0.01) increase in logPWV/mmHg increase in MAP] and smoking status (current vs. never smoker).

CONCLUSIONS

Lower insulin sensitivity at baseline appears to be an important risk factor for increased arterial stiffness over time in youth with T1D. This identifies a potentially modifiable therapeutic target.

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.