Factors associated with left atrial size in obese children: an observational study.

OBJECTIVE: Left atrial size can be considered an independent risk factor for cardiovascular diseases. The measurements of left atrium may be used to assess obesity, which is an important risk factor of cardiovascular diseases. It is aimed to determine the factors that effect to the left atrial size, which is an indicator of cardiac risk in obese children without hypertension. METHODS: The cross-sectional observational study was performed between April 2008 and September 2009 at the clinic of Pediatric Cardiology. Eighty obese and 82 lean children were studied. Diagnosis of obesity was defined according to the World Health Organization classification as the standard deviation score of body mass index being over + 2 standard deviation of the same gender and age. All subjects underwent two-dimensional, M-mode, and Doppler echocardiographic studies. Student's t-test, Chi-square test, Pearson correlation analysis, and multiple stepwise regression analyses were used to compare the subjects, differences in group proportions, evaluate the relation of variables with the left atrial size, and examine the effects of significant independent variables, respectively. RESULTS: The mean age of obese patients was 11.7±2.2 years and it of lean subjects was 11.7±2.2 years. Body weight, body mass index, standard deviation score of body mass index, waist circumference, systolic and diastolic blood pressure, fasting insulin, and insulin resistance statistically increased in obese children (p<0.05). The left atrial size statistically correlated (p<0.05) with age (r=0.523), body mass index (r=0.394), waist circumference (r=0.421), diastolic blood pressure (r=0.230), insulin resistance (r=0.350), and left ventricular mass (r=0.535). It was determined that age (beta=0.491; 95% CI=0.091-0.892; p=0.001) and left ventricular mass (beta=0.055; 95% CI=0.026-0.085; p=0.017) were the most effective independent factors associated with left atrial size among other independent factors in multiple regression analysis. CONCLUSION: We found that left atrial size was mostly influenced by age and left ventricular mass in obese children. Therefore, it is important that left atrial size is follow up in childhood obesity.

Echocardiographic measurement of epicardial adipose tissue in obese children.

The echocardiographic measurement of epicardial adipose tissue (EAT) has been suggested as an easy method for evaluation of the visceral adipose tissue and its related cardiovascular risks in adults. However, a direct effect of obesity on cardiac function is not well established, and echocardiographic EAT thickness has not been studied in children. The aims of this study were to evaluate cardiac function and echocardiographic EAT thickness and to correlate EAT with the other echocardiographic findings in obese children. The study population included 106 obese and 62 lean children. Echocardiographic indexes of systolic and diastolic function were obtained. We measured EAT thickness on the free wall of the right ventricle from parasternal long-axis views. The septal and posterior wall thicknesses, relative wall thickness, left atrial diameter, and left ventricular mass were increased (p = 0.001) in obese children. However, systolic and diastolic functions of the left ventricle were normal in the patients. The obese children had a significantly thicker EAT (p = 0.001) compared to the lean subjects. EAT thickness correlated significantly with body mass index (r = 0.50, p = 0.001), left atrial diameter (r = 0.37, p = 0.001), and left ventricular mass (r = 0.33, p = 0.001). In conclusion, the present study demonstrates a close relationship between EAT thickness and obesity in children. Assessment of EAT thickness in routine echocardiographic examinations might be used as a feasible and reliable method for the evaluation of obesity and its related cardiovascular risks during childhood.