The Impact of Obesity on Left Ventricular Hypertrophy and Diastolic Function in Caucasian Children

Abstract

Background:

Left ventricular hypertrophy (LVH) and diastolic dysfunction are correlated with obesity and hypertension in adult patients, but few studies have investigated the association between obesity itself and left ventricular function in children. The aim of this study was to evaluate the effect of obesity and LVH on left ventricular diastolic function in pediatric subjects compared with children without obesity.

Methods:

A number of 454 patients from an outpatient cardiology service were enrolled in a prospective study, 33 children with obesity, 20 overweight children, and 401 children without obesity. The subjects were assigned to three groups according to age and school grade. A standardized two-dimensional echocardiography analysis was performed in all children. The evaluated echocardiographic parameters included thickness of the interventricular septum (IVS), thickness of the posterior wall of the left ventricle, and left atrium size. The left ventricular diastolic function was analyzed by the classic pulsed-wave Doppler technique, tissue Doppler technique, and continuous Doppler technique.

Results:

The number of children with obesity was higher in the school and adolescent groups. The median age of children with obesity was 9 years. The subjects were classified according to blood pressure values in hypertensive, with high–normal blood pressure/prehypertension and with normal blood pressure values. Standard echocardiography showed that children with obesity had significantly increased thickness of the IVS and of the posterior wall compared with nonobesity subjects (P < 0.001). Left ventricular systolic function was preserved in both groups. Diastolic function was normal in the obesity group and in the non-obesity group, respectively.

Conclusions:

The results of this study demonstrate that childhood obesity is associated with significant changes in the myocardial structure consisting of LVH, but we did not find an early alteration in the left ventricular diastolic function of the subjects with obesity compared with patients with a normal weight.

Introduction

Obesity among children and adolescents is becoming an increasingly common health problem. The prevalence of obesity among the population aged 2–19 years in the United States is 18.5% (13.7 million children and adolescents).¹ Furthermore, in Europe, data on the prevalence of overweight and obesity among primary school children are not encouraging. Studies show that severe obesity affects 400,000 of the 21.7 million people aged 6–9 years from the 21 countries participating in the study.² Worrisome is the fact that overweight and obesity during childhood have been associated with cardiovascular disease and premature death in later life.³

Clinical studies have identified a number of changes in the heart geometry⁴ based on data from imaging investigations, such as echocardiography, including increased left ventricular mass and ventricular hypertrophy,⁵ parameters strongly associated with an increased risk of cardiovascular disease, and premature death among adults.³ Other changes identified among overweight children and children with obesity are high blood pressure, hypercholesterolemia, and insulin resistance, which are all associated with adverse cardiovascular events.⁶

There are studies showing that obesity and hypertension are independent factors in terms of left ventricular hypertrophy (LVH). The blood volume load in patients with obesity is consistently higher than in normal weight patients, even in the presence of blood pressure levels within the normal range.⁷ Volume overload causes compensatory changes in cardiac geometry, the consequence of being a maladaptive change in a structure characterized by eccentric LVH, whereas the result of pressure overload is concentric LVH.⁸ It is important to mention that in the case of athletes, LVH represents a physiologically adaptive mechanism of the heart depending on the type of sport performed: endurance or strength training.⁹

Objective

The main purpose of this study was to assess the prevalence of ventricular hypertrophy among the pediatric population with obesity. For this purpose, cardiac parameters were evaluated using standard echocardiography, pulsed-wave Doppler technique, tissue Doppler technique, and continuous Doppler technique both in children with obesity and in children with normal weight. Furthermore, we investigated other clinical factors that could influence the left ventricular mass such as anthropometric factors, blood pressure, and biochemical parameters including serum total cholesterol levels.

Materials and Methods

Patients

This study was carried out based on echocardiographic data collected from 454 children and adolescents, 234 boys and 220 girls, aged 0–17 years, of whom 33 had obesity (20 boys and 13 girls), 20 were overweight (9 boys and 11 girls), and 401 children had a normal weight (205 boys and 196 girls). All children underwent the aforementioned procedure due to cardiac murmurs detected by the general practitioner during routine examinations, dyspnea, heart palpitations, syncope or angina, or just because of parents' request.

The subjects were assigned to three groups according to age and school grade: 268 were aged 0 to pre-school (0–6 years old, of whom 11 had obesity, 9 were overweight), 117 school children (7–11 years old, 14 had obesity, 6 were overweight), and 69 adolescents (12–17 years old, 8 had obesity, 5 were overweight). None of the patients with obesity included in the study had a previous diagnosis of arrhythmia, congenital heart defects, or pulmonary hypertension.

An informed consent was signed by the legal guardians of all children included in the study, expressing their agreement to participate in this study. The study protocol was approved by the local ethics committee.

Echocardiographic measurements

A thorough echocardiographic evaluation of each patient included in our study was performed. For this purpose, we used a General Electric echocardiography device, Vivid 6S model. The windows and views used to collect the necessary data for the study were the standard windows for echocardiography in children, which include: parasternal views, apical views, subcostal views, and suprasternal views.¹⁰ For the assessment of the heart chambers, wall thickness, ventricular function, and valve function, a standardized two-dimensional echocardiography analysis was performed in all children. The echocardiographic parameters used in our study were thickness of the interventricular septum (IVS), thickness of the posterior wall of the left ventricle (PWLV), and left atrium size.

The left ventricular diastolic function was analyzed according to the current guidelines using the classic pulsed-wave Doppler technique (mitral flow, pulmonary vein flow), tissue Doppler technique, and continuous Doppler technique (tricuspid regurgitation systolic jet velocity).

All children were examined by the same cardiologist in left lateral position, in a dark room. The evaluations of left ventricular changes were interpreted using the percentile values of left ventricular measurements for age and gender.¹¹

Laboratory procedures

Laboratory tests were performed in each patient included in our study. We determined the plasma level of total cholesterol.

Anthropometric measurements and demographic data

All subjects in this study were Caucasians. Data regarding sex and age were collected for each patient.

To define obesity and overweight, the Centers for Disease Control and Prevention (CDC) growth charts were used for children and adolescents aged between 2 and 17 years.

Body mass index (BMI) for age and sex growth charts was utilized to establish the presence of overweight/obesity. The children aged between 2 and 17 years were classified as follows: obesity group BMI for age ≥95th percentile, overweight group BMI for age ≥85th and <95th percentile, normal weight ≥5th and <85th percentile, and underweight group <5th percentile.¹² For the subjects aged between 0 and 2 years, the World Health Organization weight-for-length charts were used, and the subjects were classified as follows: obesity group (high weight for length group) >98th percentile, underweight group (low weight for length group) <2nd percentile, and the normal weight group (normal weight for length group) between 2nd and 98th percentile.¹³

The office systolic blood pressure and diastolic blood pressure were measured after a 5 min rest, in sitting position, using an appropriate size blood pressure cuff. The blood pressure data were expressed as percentiles by sex, age, and height or length for children aged between 1 and 17 years, and the subjects were classified as follows: the grade I hypertension group between 95th and 99th percentile, group with normal high blood pressure/prehypertension between 90th and 95th percentile, and normal blood pressure group between 50th percentile and 90th percentile.¹⁴ For infants and neonates, the Pediatric Intensive Care Unit (PICU) chart was used to evaluate the blood pressure values.¹⁵

Electrocardiogram data

Each subject included in the study underwent an electrocardiogram procedure to identify any indications suggestive of LVH or arrhythmias.

Statistical analysis

Statistical analysis was performed using the statistical packages SPSS 19.0 (IBM Corporation, Armonk, NY) and MedCalc version 10.3.0.0 (MedCalc Software, Ostend, Belgium). Qualitative variables are presented as absolute values and percentages. After testing quantitative variables for normal distribution (using the Kolmogorov test), these are reported as mean ± standard deviation and median value, respectively. The chi-squared test, independent-sample t-test, or Mann–Whitney test were used to assess differences between variables. A P value <0.05 was considered statistically significant.

Results

A total of 454 patients, aged 0–17 years, all Caucasians, were included in our study.

The subjects were assigned to three groups according to age and school grade: 268 (59%) patients were aged between 0 and 6 years, 117 (25.8%) school children were aged between 7 and 11 years, and 69 (15.2%) patients were adolescents (12–17 years old).

The gender distribution in this study was 234 (51.5%) boys and 220 (48.5%) girls. The global mean age was 5.97 ± 4.77 (median value 5) years, with no significant difference between boys and girls.

Of all children included in the study, 7.26% (33 subjects) had obesity: 13 of these were girls (5.9% of all girls) and 20 were boys (8.54% of all boys); 4.4% (20 subjects) were overweight: 11 of these were girls (5% of all girls) and 9 were boys (3.84% of all boys). The number of children with obesity was higher in school (11.96%) and adolescent (11.59%) groups. The mean age of children with obesity was 8.66 ± 3.53 (median value 9) years, and of children with overweight 7.58 ± 5.84 (median value 7) years.

Blood pressure measurements were performed in all children; 103 (22.7%) had high–normal blood pressure/prehypertension [73 patients (16.1%)] or hypertension [30 patients (6.6%)]; 351 (77.3%) had normal blood pressure values, with no significant differences between genders. Two (0.5%) children with high serum total cholesterol levels were identified. Four (0.88%) patients included in the study had been previously diagnosed with type 1 diabetes (3 girls and 1 boy).

All data regarding patients' characteristics are presented in Table 1.

Table 1.

Patients' Characteristics

	Global	Boys	Girls	P
	454 patients	234	220	P
Age, years, n (%)
0–6	268 (59)	140 (59.83)	128 (58.18)	ns
7–11	117 (25.8)	56 (23.93)	61 (27.73)
12–17	69 (15.2)	38 (16.24)	31 (14.09)
Age,^a years
Mean ± SD (median)	5.97 ± 4.77 (5)	5.94 ± 4.78 (5)	6.00 ± 4.78 (5)	ns
Obesity
n (%)—yes	33 (7.3 of all patients)	20 (8.54 of all boys)	13 (5.9 of all girls)
0–6	11 (33.33 of patients with obesity)	6 (30 of patients with obesity)	5 (38.46 of patients with obesity)	ns
7–11	14 (42.42)	8 (40)	6 (46.15)
12–17	8 (24.24)	6 (30)	2 (15.38)
Overweight
n (%)—yes	20 (4.4 of all patients)	9 (3.84 of all boys)	11 (5 of all girls)
0–6	9 (45 of overweight patients)	5 (55.55 of overweight patients)	4 (36.36 of overweight patients)	ns
7–11	6 (30)	1 (11.11)	5 (45.45)
12–17	5 (25)	3 (33.33)	2 (18.18)
Hypertension
n (%)—yes	30 (6.6 of all patients)	18 (7.69 of all boys)	12 (5.45 of all girls)	ns
0–6	20 (66.66 of hypertensive)	12 (66.66 of hypertensive)	8 (66.66)	—
7–11	3 (10)	1 (5.55)	2 (16.66)
12–17	7 (23.33)	5 (27.77)	2 (16.66)
Prehypertension normal high blood pressure
n (%)—yes	73 (16.07 of all patients)	37 (15.81 of all boys)	36 (16.36 of all girls)	ns
0–6	51 (69.86 of prehypertensive/normal high)	24 (64.86 of prehypertensive/normal high)	27 (75 of prehypertensive/normal high)
7–11	7 (9.58)	3 (8.1)	4 (11.11)
12–17	15 (20.54)	10 (27.02)	5 (13.88)
Diabetes
n (%)—yes	4 (0.88 of all patients)	1 (0.42 of all patients)	3 (1.36 of all patients)	ns
0–6	1 (25 of all diabetes)	0 (0)	1 (33.33)
7–11	0 (0)	0 (0)	0 (0)
12–17	3 (75)	1 (100)	2 (66.66)
IVS^a
Mean ± SD (median)	5.9 ± 2.14 (5.5)	5.93 ± 1.74 (5.5)	5.87 ± 2.49 (5.5)	ns
0–6	5.07 ± 2.11 (5)	5.06 ± 1.11 (5)	5.09 ± 2.83 (5)	ns
7–11	6.51 ± 1.23 (6)	6.48 ± 1.35 (6.25)	6.54 ± 1.12 (6)	ns
12–17	8.09 ± 1.46 (8)	8.37 ± 1.52 (8.4)	7.75 ± 1.34 (8)	0.055
PWLV^a
Mean ± SD (median)	5.94 ± 1.63 (6)	6.02 ± 1.76 (6)	5.85 ± 1.49 (6)	ns
0–6	5.02 ± 1.04 (5)	5.08 ± 1.13 (5)	4.96 ± 0.94 (5)	ns
7–11	6.68 ± 1.11 (6)	6.68 ± 1.23 (6)	6.68 ± 1.00 (6)	ns
12–17	8.24 ± 1.34 (8)	8.51 ± 1.44 (9)	7.91 ± 1.14 (8)	0.033

Does not respect normal distribution.

IVS, interventricular septum; ns, not statistically significant; PWLV, posterior wall of left ventricle; SD, standard deviation.

Standard echocardiography showed for the IVS mean value of 5.9 ± 2.14 (median value 5.5) mm and for the PWLV mean value of 5.94 ± 1.63 (median value 6), with no significant difference between boys and girls. Further analysis evidenced significant differences between boys and girls in the 12–17 years age group [for IVS 8.37 ± 1.52 (median value 8.4) vs. 7.75 ± 1.34 (median value 8), P = 0.055 at limit, and for PWLV 8.51 ± 1.44 (median value 9) vs. 7.91 ± 1.14 (median value 8), P = 0.0033].

Following the analysis of the entire group, significant differences were found between obesity and nonobesity/nonoverweight patients regarding IVS [7.55 ± 1.59 (median value 7) vs. 5.72 ± 2.12 (median value 5), P < 0.0001] at the general level and in both boys [7.44 ± 1.65 (median value 7.25) vs. 5.74 ± 1.63 (median value 5), P < 0.0001] and girls [7.73 ± 1.54 (median value 7) vs. 5.7 ± 2.53 (median value 5), P < 0.0001].

The same relationship was found for PWLV, differences being significant between obesity and nonobesity patients of both genders [boys 7.6 ± 1.51 (median value 8) vs. 5.8 ± 1.66 (median value 6), P < 0.0001, and girls 7.8 ± 1.42 (median value 7.5) vs. 5.66 ± 1.38 (median value 5.5), P < 0.0001]. All detailed data are presented in Tables 2 –4.

Table 2.

Differences Between Patients with Obesity Versus Patients Without Obesity at Global Level

	Obesity				Nonobesity/nonoverweight			No HBP	P^a
	Global	HBP	Pre-HBP/NH	No HBP	Global	HBP	Pre-HBP/NH	No HBP
	33 patients	5 patients	3 patients	25 patients	401 patients	24 patients	66 patients	311 patients
All
IVS	7.55 ± 1.59 (7)	7.4 ± 1.67 (7)	7.33 ± 1.44 (6.5)	7.61 ± 1.65 (7.5)	5.72 ± 2.12 (5)	5.7 ± 1.39 (5)	5.92 ± 1.52 (5.5)	5.68 ± 2.27 (5)	<0.0001
PWLV	7.68 ± 1.46 (7.5)	7.6 ± 1.34 (7)	7.66 ± 1.15 (7)	7.7 ± 1.56 (8)	5.74 ± 1.53 (6)	5.72 ± 1.48 (5)	6.02 ± 1.54 (6)	5.69 ± 1.53 (6)	<0.0001
0–6 Years
IVS	6.63 ± 1.16 (6.5)	6 ± 1.41 (6)	6.5 (6.5)	6.85 ± 1.31 (7)	5.00 ± 2.15 (5)	5 ± 0.59 (5)	5.36 ± 1.03 (5)	4.9 ± 2.44 (5)	<0.0001
PWLV	6.81 ± 0.87 (7)	6.5 ± 0.7 (6.5)	7 (7)	6.85 ± 1.06 (6.5)	4.93 ± 0.99 (5)	5.02 ± 0.49 (5)	5.42 ± 1.06 (5)	4.79 ± 0.97 (5)	<0.0001
7–11 Years
IVS	7.39 ± 1.34 (7)	—	9 (9)	7.26 ± 1.31 (7)	6.35 ± 1.18 (6)	7.66 ± 0.57 (8)	5.9 ± 0.54 (6)	6.33 ± 1.2 (6)	0.0035
PWLV	7.67 ± 1.42 (7.75)	—	9 (9)	7.57 ± 1.42 (7.5)	6.49 ± 0.99 (6)	7.33 ± 2.08 (8)	6.2 ± 0.44 (6)	6.48 ± 0.96 (6)	0.0017
12–17 Years
IVS	9.1 ± 1.48 (8.9)	8.33 ± 1.15 (9)	—	9.56 ± 1.57 (8.8)	7.83 ± 1.38 (8)	8 ± 1 (8)	8.2 ± 1.37 (8)	7.71 ± 1.41 (8)	0.0489
PWLV	8.87 ± 1.45 (8.5)	8.33 ± 1.15 (9)	—	9.2 ± 1.64 (8)	8.05 ± 1.28 (8)	8.33 ± 0.57 (8)	8.37 ± 1.18 (8)	7.93 ± 1.34 (8)	0.1675

Values are presented as mean ± SD (median).

Between obesity and nonobesity patients at global level.

HBP, high blood pressure/hypertension; Pre-HBP/NH, prehypertension or normal high.

Table 3.

Differences Between Obesity Versus Nonobesity Patients in Boys

	Obesity				Nonobesity/nonoverweight				P^a
	Global	HBP	Pre-HBP/NH	No HBP	Global	HBP	Pre-HBP/NH	No HBP
	20 patients	5 patients	1 patient	14 patients	205 patients	12 patients	35 patients	158 patients
All
IVS	7.44 ± 1.65 (7.25)	7.4 ± 1.67 (7)	9 ± 0 (9)	7.34 ± 1.71 (7.25)	5.74 ± 1.63 (5)	5.25 ± 0.96 (5)	6.3 ± 1.77 (5.5)	5.66 ± 1.62 (5)	<0.0001
PWLV	7.6 ± 1.51 (8)	7.6 ± 1.34 (7)	9 ± 0 (9)	7.5 ± 1.62 (8)	5.82 ± 1.66 (6)	5.45 ± 1.23 (5)	6.42 ± 1.75 (6)	5.71 ± 1.65 (6)	<0.0001
0–6 Years
IVS	6.33 ± 1.5 (6)	6 ± 1.41 (6)	—	6.5 ± 1.73 (6)	4.99 ± 1.08 (5)	4.9 ± 0.56 (5)	5.45 ± 1.13 (5)	4.89 ± 1.08 (5)	0.0188
PWLV	6.5 ± 1 (6.5)	6.5 ± 0.7 (6.5)	—	6.5 ± 1.22 (6.5)	5.0 ± 1.11 (5)	4.95 ± 0.36 (5)	5.58 ± 1.13 (5.5)	4.86 ± 1.11 (5)	0.0025
7–11 Years
IVS	7.25 ± 1.36 (7.25)	—	9 ± 0 (9)	7 ± 1.25 (7)	6.34 ± 1.33 (6)	7 ± 0 (7)	6.25 ± 0.35 (6.25)	6.32 ± 1.37 (6)	0.0389
PWLV	7.62 ± 1.48 (8.25)	—	9 ± 0 (9)	7.42 ± 1.48 (8)	6.52 ± 1.14 (6)	8 ± 0 (8)	6.5 ± 0.7 (6.5)	6.48 ± 1.15 (6)	0.0317
12–17 Years
IVS	8.8 ± 1.32 (8.9)	8.33 ± 1.15 (9)	—	9.26 ± 1.55 (8.8)	8.12 ± 1.5 (8)	7 ± 0 (7)	8.55 ± 1.33 (9)	7.97 ± 1.6 (8)	0.4181
PWLV	8.66 ± 1.36 (8.5)	8.33 ± 1.15 (9)	—	9 ± 1.73 (8)	8.32 ± 1.44 (8.5)	8 ± 0 (8)	8.66 ± 1.22 (9)	8.18 ± 1.57 (8.5)	0.7928

Values are presented as mean ± SD (median).

Between obesity and nonobesity patients at global level.

Table 4.

Differences Between Obesity Versus Nonobesity Patients in Girls

	Obesity				Nonobesity/nonoverweight			No HBP	P^a
	Global	HBP	Pre-HBP/NH	No HBP	Global	HBP	Pre-HBP/NH	No HBP
	13 patients	0 patients	2 patients	11 patients	196 patients	12 patients	31 patients	153 patients
All
IVS	7.73 ± 1.54 (7)	—	6.5 ± 0 (6.5)	7.95 ± 1.58 (7.5)	5.7 ± 2.53 (5)	6.16 ± 1.64 (5.5)	5.5 ± 1.07 (5.5)	5.7 ± 2.79 (5)	<0.0001
PWLV	7.8 ± 1.42 (7.5)	—	7 ± 0 (7)	7.95 ± 1.5 (7.5)	5.66 ± 1.38 (5.5)	6 ± 1.7 (5)	5.5 ± 1.11 (6)	5.66 ± 1.41 (5.5)	<0.0001
0–6 Years
IVS	7 ± 0.5 (7)	—	6.5 ± 0 (6.5)	7.33 ± 0.28 (7.5)	5.0 ± 2.9 (5)	5.12 ± 0.64 (5)	5.28 ± 0.95 (5.5)	4.91 ± 3.37 (5)	0.0003
PWLV	7.2 ± 0.57 (7)	—	7 ± 0 (7)	7.33 ± 0.76 (7.5)	4.85 ± 0.84 (5)	5.12 ± 0.64 (5)	5.28 ± 0.97 (5)	4.71 ± 0.77 (5)	0.0002
7–11 Years
IVS	7.58 ± 1.42 (7)	—	—	7.58 ± 1.42 (7)	6.37 ± 1.04 (6)	8 ± 0 (8)	5.66 ± 0.57 (6)	6.34 ± 1.02 (6)	0.0298
PWLV	7.75 ± 1.47 (7.25)	—	—	7.75 ± 1.47 (7.25)	6.47 ± 0.84 (6)	7 ± 2.82 (7)	6 ± 0 (6)	6.47 ± 0.76 (6)	0.0235
12–17 Years
IVS	10 ± 2.12 (10)	—	—	10 ± 2.12 (10)	7.53 ± 1.18 (7.5)	8.5 ± 0.7 (8.5)	7.16 ± 1.04 (7.5)	7.5 ± 1.22 (7.25)	0.0707
PWLV	9.5 ± 2.12 (9.5)	—	—	9.5 ± 2.12 (9.5)	7.75 ± 1.04 (7.5)	8.5 ± 0.7 (8.5)	7.5 ± 0.5 (7.5)	7.72 ± 1.10 (7.5)	0.1320

Values are presented as mean ± SD (median).

Between obesity and nonobesity patients at global level.

Left ventricular systolic function was preserved in both groups. Diastolic function was normal in the obesity group and in the nonobesity group, respectively.

Discussion

In this study, we investigated the relationship between obesity and cardiac geometry, independent of hypertension. Our data demonstrated that normotensive children with obesity present early asymptomatic changes in a myocardial structure consisting of LVH. We found significant differences between children with and without obesity regarding PWLV and IVS. These alterations were present in both girls and boys. The left ventricular systolic function was preserved in both groups. Also, we did not find changes in the diastolic function of the children with or without obesity. In our study, we included Caucasian children from Romania; therefore, our article accurately reflects the situation in our country. The prevalence of obesity and overweight in the pediatric population is strongly influenced by local eating habits and lifestyle.

Co-morbidities associated with obesity can cause significant damage to the cardiovascular system.¹⁶ The purpose of our study was to demonstrate that obesity itself has a significant impact on cardiac geometry, given that children generally have no co-morbidities. We were able to demonstrate that overweight children have IVS and posterior wall hypertrophy compared with nonobesity patients. We found no changes in cardiac diastolic function, but the present study focused on resting cardiac function. It is possible that the evaluation performed under stress conditions could provide other results regarding diastolic function, being even able to detect early cardiac dysfunction in the case of subjects with obesity and cardiac function within the normal range in resting conditions.¹⁷

The interpretation of cardiac parameters in children is challenging, given that they must be related to physical parameters such as age, BMI, sex, height, and lean body mass.¹⁸ In our study, we evaluated cardiac size in relation to the patients' BMI, sex, and age.

Factors associated with changes in cardiac geometry in children with obesity include, in addition to hypertension (HT), increased cardiac output,¹⁹ local effects of the renin–angiotensin–aldosterone system, and insulin resistance syndrome.²⁰

Since studies are showing that childhood obesity may be a risk factor for cardiovascular disease in adulthood,²¹ early diagnosis of heart changes in children with obesity and their long-term follow-up are crucial.

It is important to mention the fact that some studies demonstrated the beneficial effects of weight loss on changes in cardiac geometry. In addition, the most important predictor of left ventricular mass index decrease was a reduction in abdominal fat expressed as a decrease in waist circumference.²² Moreover, studies conducted in treated hypertensive adult patients show that residual LVH is much more common in subjects with obesity than in normal weight individuals,²³ which further emphasizes the importance of weight loss simultaneously with antihypertensive treatment.

In daily clinical practice, it is important to advise children and their families on the importance of weight loss and embracing a healthy lifestyle together with regular outdoor physical activity.

Study limitations

Our study has some limitations. First of all, the current study included only Caucasian subjects, so our results cannot be extrapolated to other populations. Also, we did not evaluate the effect of other cardiometabolic risk factors, such as fasting blood glucose, insulinemia, and the presence of systemic inflammation in the assessment of cardiovascular risk.

Another shortcoming of this study is the small sample of subjects with obesity in relation to normal weight children. Also, the age of the subjects included in the study may have influenced the results, children included in our study having an average age (9 years), which is much lower than the mean age of the subjects included in other studies (11 and 14 years, respectively).

Our results are also based on examinations performed in resting conditions. Stress examinations might have identified changes that we could have missed in our investigation.

In our study, we used office blood pressure measurements, which do not match the quality of ambulatory blood pressure measurements.

Conclusions

The results of this study demonstrate that childhood obesity is associated with significant changes in myocardial structure consisting of LVH, but we did not find an early alteration in the left ventricular diastolic function of subjects with obesity compared with nonobesity patients. All these suggest that the adverse effects of obesity on the cardiovascular system have an early onset and emphasize the importance of identifying these changes and treating them to prevent their consequences in adult life.

Footnotes

Author Disclosure Statement

No conflicting financial interests exist.

Funding Information

The authors received no funding for this research article.

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