Childhood obesity and cardiac remodeling

Early cardiac dysfunction in obese adolescents with Down syndrome or autism

BACKGROUND

Obesity in adolescents with intellectual and developmental disabilities) occurs at twice the frequency as their typically developing peers. Typically developing adolescents with obesity have abnormal cardiac function (as measured by strain echocardiography) and cardiac mass, but the effects of obesity on cardiac health in adolescents with Down syndrome or autism spectrum disorder are unknown. The purpose of this study was to evaluate the impact of body mass index on cardiac function in adolescents with Down syndrome or autism.

METHODS

Adolescents (age 12-21 years) with Down syndrome (n = 28), autism (n = 33), and age-/sex-matched typically developing controls (n = 15) received an echocardiogram optimised for strain analysis at a single timepoint. Measures of ventricular function, mass, and size were collected. Regression modelling evaluated the impact of body mass index and intellectual and developmental disabilities diagnosis on these cardiac measures.

RESULTS

In regression modelling, an elevated body mass index z-score was associated with diminished systolic biventricular function by global strain (left ventricular longitudinal strain β 0.87, P < 0.001; left ventricular circumferential strain β 0.57, p 0.003; right ventricular longitudinal strain β 0.63, P < 0.001). Diminished left ventricular diastolic function by early diastolic strain rate was also associated with elevated body mass index (global longitudinal end-diastolic strain rate β -0.7, P < 0.001). No association was found between traditional (non-strain) measures of systolic and diastolic ventricular function and body mass index z-score.

CONCLUSIONS

Obesity in adolescents with Down syndrome or autism negatively impacts cardiac function as measured by echocardiographic strain analysis that was not detected by traditional parameters.

Changes in Nutritional State and Cardiovascular Parameters in Alimentary Obese Children after a Month-Long Stay in Children's Treatment Center

Childhood and adolescent obesity has become an important public health issue, as it leads to higher risk of cardio−metabolic, orthopedic, and psychological comorbidities. The aim of this study was to evaluate the changes in nutritional state and cardiovascular system parameters in obese children. Sixty respondents aged 9−17 years with alimentary obesity participated in this research. Anthropometric parameters (body weight (BWT), body mass index (BMI), percentage of body fat (%), waist and hip circumference (WC and HC), waist−hip ratio (WHR)) and cardiovascular parameters (systolic and diastolic blood pressure (SP and DP), cardio-ankle vascular index (CAVI), ankle-brachial index (ABI), pulse wave velocity and its variability (PWV and PWVV), and parameters of pulse wave analysis) were measured. Every respondent went through two sets of measurements, the first (I.) after their admission to the children’s hospital and the second (II.) at the end of their one-month-long therapeutic stay. Statistically significant differences between measurements I. and II. were observed in the following parameters: BWT (p < 0.01), BMI (p < 0.01), WC (p < 0.01), HC (p < 0.01), DP (p < 0.01), PWV (p < 0.05), and ABI (p < 0.01). The results of this study show that obesity has a mostly negative impact on the cardiovascular health of affected children, with likely negative results in their adulthood.

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

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

The Influence of Surgical Weight Reduction on Left Atrial Strain

Background

Obesity increases and surgical weight reduction decreases the risk of atrial fibrillation (AF) and heart failure (HF). We hypothesized that surgically induced weight loss may favorably affect left atrial (LA) mechanical function measured by longitudinal strain, which has recently emerged as an independent imaging biomarker of increased AF and HF risk.

Methods

We retrospectively evaluated echocardiograms performed before and 12.2 ± 2.2 months after bariatric surgery in 65 patients with severe obesity (mean age 39 [36; 47] years, 72% of females) with no known cardiac disease or arrhythmia. The LA mechanical function was measured by the longitudinal strain using the semi-automatic speckle tracking method.

Results

After surgery, body mass index decreased from 43.72 ± 4.34 to 30.04 ± 4.33 kg/m². We observed a significant improvement in all components of the LA strain. LA reservoir strain (LASR) and LA conduit strain (LASCD) significantly increased (35.7% vs 38.95%, p = 0.0005 and − 19.6% vs − 24.4%, p < 0.0001) and LA contraction strain (LASCT) significantly decreased (− 16% vs − 14%, p = 0.0075). There was a significant correlation between an increase in LASR and LASCD and the improvement in parameters of left ventricular diastolic and longitudinal systolic function (increase in E’ and MAPSE). Another significant correlation was identified between the decrease in LASCT and an improvement in LA function (decrease in A’).

Conclusions

The left atrial mechanical function improves after bariatric surgery. It is partially explained by the beneficial effect of weight reduction on the left ventricular diastolic and longitudinal systolic function. This effect may contribute to decreased risk of AF and HF after bariatric surgery.

Graphical abstract

Cardiovascular Risk Factors in Childhood and Left Ventricular Diastolic Function in Adulthood

BACKGROUND AND OBJECTIVES

Cardiovascular risk factors, such as obesity, blood pressure, and physical inactivity, have been identified as modifiable determinants of left ventricular (LV) diastolic function in adulthood. However, the links between childhood cardiovascular risk factor burden and adulthood LV diastolic function are unknown. To address this lack of knowledge, we aimed to identify childhood risk factors associated with LV diastolic function in the participants of the Cardiovascular Risk in Young Finns Study.

METHODS

Study participants (N = 1871; 45.9% men; aged 34-49 years) were examined repeatedly between the years 1980 and 2011. We determined the cumulative risk exposure in childhood (age 6-18 years) as the area under the curve for systolic blood pressure, adiposity (defined by using skinfold and waist circumference measurements), physical activity, serum insulin, triglycerides, total cholesterol, and high- and low-density lipoprotein cholesterols. Adulthood LV diastolic function was defined by using E/é ratio.

RESULTS

Elevated systolic blood pressure and increased adiposity in childhood were associated with worse adulthood LV diastolic function, whereas higher physical activity level in childhood was associated with better adulthood LV diastolic function (P < .001 for all). The associations of childhood adiposity and physical activity with adulthood LV diastolic function remained significant (both P < .05) but were diluted when the analyses were adjusted for adulthood systolic blood pressure, adiposity, and physical activity. The association between childhood systolic blood pressure and adult LV diastolic function was diluted to nonsignificant (P = .56).

CONCLUSIONS

Adiposity status and the level of physical activity in childhood are independently associated with LV diastolic function in adulthood.

Association of abdominal obesity and high blood pressure with left ventricular hypertrophy and geometric remodeling in Chinese children

BACKGROUND AND AIMS

Many studies have examined the association between overweight or obesity assessed by body mass index and left ventricular hypertrophy (LVH) in children or adolescents, but only few studies have assessed the relation with abdominal obesity in children. This study aimed to assess the association of abdominal obesity assessed by waist circumference (WC), high blood pressure (BP) and their joint effect on LVH and left ventricular (LV) geometric remodeling in Chinese children.

METHODS AND RESULTS

Data were from a cross-sectional survey of 1319 Chinese children aged 6-11 years who had undergone cardiac ultrasound. Compared with normal WC, the adjusted odds ratios (ORs) for abdominal obesity were 6.78 (95% confidence interval [CI] 3.77-12.16) for LVH, 2.80 (1.55-5.05) for CR, 5.43 (2.84-10.39) for EH, and 20.05 (4.46-90.08) for CH, respectively. Compared with children with both normal WC and normal BP, the adjusted ORs for those with abdominal obesity and normal BP were 6.98 (3.71-13.10) for LVH, 2.87 (1.47-5.60) for CR, 5.52 (2.70-11.26) for EH, and 15.20 (4.51-78.13) for CH. The adjusted ORs for those with abdominal obesity and high BP were 7.12 (3.27-15.50) for LVH, 4.71 (2.04-10.85) for CR, 7.49 (3.23-17.40) for EH, and 8.65 (1.32-56.89) for CH. The ORs for those with high BP and normal WC were not significant for these cardiac outcomes (P > 0.05).

CONCLUSIONS

LVH and LV geometric remodeling were associated more strongly with abdominal obesity than with high BP in Chinese children, stressing the need to prevent childhood abdominal obesity for reducing cardiac risk.

The Roles of Noncardiomyocytes in Cardiac Remodeling

Cardiac remodeling is a common characteristic of almost all forms of heart disease, including cardiac infarction, valvular diseases, hypertension, arrhythmia, dilated cardiomyopathy and other conditions. It is not merely a simple outcome induced by an increase in the workload of cardiomyocytes (CMs). The remodeling process is accompanied by abnormalities of cardiac structure as well as disturbance of cardiac function, and emerging evidence suggests that a wide range of cells in the heart participate in the initiation and development of cardiac remodeling. Other than CMs, there are numerous noncardiomyocytes (non-CMs) that regulate the process of cardiac remodeling, such as cardiac fibroblasts and immune cells (including macrophages, lymphocytes, neutrophils, and mast cells). In this review, we summarize recent knowledge regarding the definition and significant effects of various non-CMs in the pathogenesis of cardiac remodeling, with a particular emphasis on the involved signaling mechanisms. In addition, we discuss the properties of non-CMs, which serve as targets of many cardiovascular drugs that reduce adverse cardiac remodeling.

Oral administration of alcalase potato protein hydrolysate-APPH attenuates high fat diet-induced cardiac complications via TGF-β/GSN axis in aging rats

Consumption of high fat diet (HFD) is associated with increased cardiovascular risk factors among elderly people. Aging and obesity induced-cardiac remodeling includes hypertrophy and fibrosis. Gelsolin (GSN) induces cardiac hypertrophy and TGF-β, a key cytokine, which induces fibrosis. The relationship between TGF-β and GSN in aging induced cardiac remodeling is still unknown. We evaluated the expressions of TGF-β and GSN in HFD fed 22 months old aging SD rats, followed by the administration of either probucol or alcalase potato protein hydrolysate (APPH). Western blotting and Masson trichrome staining showed that APPH (45 and 75 mg/kg/day) and probucol (500 mg/kg/day) treatments significantly reduced the aging and HFD-induced hypertrophy and fibrosis. Echocardiograph showed that the performance of the hearts was improved in APPH, and probucol treated HFD aging rats. Serum from all rats was collected and H9c2 cells were cultured with collected serums separately. The GSN dependent hypertrophy was inhibited with an exogenous TGF-β in H9c2 cells cultured in HFD+ APPH treated serum. Thus, we propose that along with its role in cardiac fibrosis, TGF-β also acts as an upstream activator of GSN dependent hypertrophy. Hence, TGF-β in serum could be a promising therapeutic target for cardiac remodeling in aging and/or obese subjects.

Impaired right ventricular contractile function in childhood obesity and its association with right and left ventricular changes: a cine DENSE cardiac magnetic resonance study

BACKGROUND

Pediatric obesity is a growing public health problem, which is associated with increased risk of cardiovascular disease and premature death. Left ventricular (LV) remodeling (increased myocardial mass and thickness) and contractile dysfunction (impaired longitudinal strain) have been documented in obese children, but little attention has been paid to the right ventricle (RV). We hypothesized that obese/overweight children would have evidence of RV remodeling and contractile dysfunction.

METHODS

One hundred and three children, ages 8-18 years, were prospectively recruited and underwent cardiovascular magnetic resonance (CMR), including both standard cine imaging and displacement encoding with stimulated echoes (DENSE) imaging, which allowed for quantification of RV geometry and function/mechanics. RV free wall longitudinal strain was quantified from the end-systolic four-chamber DENSE image. Linear regression was used to quantify correlations of RV strain with LV strain and measurements of body composition (adjusted for sex and height). Analysis of variance was used to study the relationship between RV strain and LV remodeling types (concentric remodeling, eccentric/concentric hypertrophy).

RESULTS

The RV was sufficiently visualized with DENSE in 70 (68%) subjects, comprising 36 healthy weight (13.6 ± 2.7 years) and 34 (12.1 ± 2.9 years) obese/overweight children. Obese/overweight children had a 22% larger RV mass index (8.2 ± 0.9 vs 6.7 ± 1.1 g/m2.7, p < 0.001) compared to healthy controls. RV free wall longitudinal strain was impaired in obese/overweight children (-16 ± 4% vs -19 ± 5%, p = 0.02). Ten (14%) out of 70 children had LV concentric hypertrophy, and these children had the most impaired RV longitudinal strain compared to those with normal LV geometry (-13 ± 4% vs -19 ± 5%, p = 0.002). RV longitudinal strain was correlated with LV longitudinal strain (r = 0.34, p = 0.004), systolic blood pressure (r = 0.33, p = 0.006), as well as BMI z-score (r = 0.28, p = 0.02), waist (r = 0.31, p = 0.01), hip (r = 0.40, p = 0.004) and abdominal (r = 0.38, p = 0.002) circumference, height and sex adjusted.

CONCLUSIONS

Obese/overweight children have evidence of RV remodeling (increased RV mass) and RV contractile dysfunction (impaired free wall longitudinal strain). Moreover, RV longitudinal strain correlates with LV longitudinal strain, and children with LV concentric hypertrophy show the most impaired RV function. These results suggest there may be a common mechanism underlying both remodeling and dysfunction of the left and right ventricles in obese/overweight children.