Study of the Effects of Adolescent Weight Disorders (Obesity, Anorexia Nervosa) on Heart Function

Overview

The study aims to better understand the functioning of the heart of children and adolescents with anorexia nervosa or obesity, compared to the heart function of control subject. This project seeks to find out if a weight disorder affects the heart and whether a systematic cardiac assessment with appropriate management is then to be considered. To meet this objective, several analyzes are planned including a speckle tracking echocardiography, allowing a non-invasive study of myocardial deformations. The hypothesis is that two opposite weight disorders (anorexia nervosa and obesity) lead to similar complications: inflammation, fibrosis altering the myocardial structure and therefore its contractility. Both systolic and diastolic dysfunction appear. Investigator hypothesize that the determinants of this dysfunction involve part of the alteration of body mass, and partly qualitative alterations specific to each pathology.

The main objective is to evaluate the cardiac dysfunctions through the study of myocardial deformities in anorexic and obese adolescents, in comparison with controls. The choice of a pediatric population is explained by the probable precocity of the cardiac repercussions of these weight disorders. The desire to bring together in the same study two opposite weight disorders is because a certain number of complications are common to both: repercussions on the cardiac mass, presence of chronic systemic inflammation, and fibrosis. Comparison to normo-weighted healthy subjects will make it possible to determine whether certain alterations are directly attributable to body composition (in the case of a continuum of a parameter between the three groups) or, on the contrary, independent of body composition. The search for the mechanisms at the origin of these alterations represents our secondary objective. For this, a correlation of the cardiac parameters with several factors such as: duration and severity of disorders, body composition, heart mass, presence of myocardial fibrosis, epicardial fat level, sympatho-vagal balance (by the cardiac variability), systemic inflammatory profile and potential pathways signaling involved (metabolomic analysis) will be carried out. All these parameters may impact cardiac function. Adolescent girls participating in the study will benefit from a clinical examination with fat / lean body mass measurement by impedance, assessment of heart rate variability, blood test (inflammation marker, metabolomic analysis) and ultrasound heart. Thus, screening for heart disease, and more generally complications of their pathology, will be performed. This project is important to answer the question of the necessity or not of a systematic cardiac assessment in these adolescents and the setting up of an adapted care