Longitudinal trends of body composition in Anorexia Nervosa: Cardiac functioning impacts the restoration of fat-free mass at three-months follow-up.

Background and aims: Predictors of outcomes are needed in order to improve the clinical management of patients with Anorexia Nervosa (AN). The present study evaluated whether cardiac dysfunction might be associated with different longitudinal outcomes of AN.

Methods and results: A sample of 35 patients with AN (11 restricting, 24 binge-purging- age range 16-28 years old) and 42 healthy controls (18-29 years old) were evaluated in terms of psychometric variables, Body Mass Index (BMI), body composition (by bioimpedance analysis, namely: Fat-Free Mass - FFM, Fat Mass - FM, Body Cell Mass - BCM, Phase Angle - PhA) and cardiac functioning (left ventricular ejection fraction - LVEF; global longitudinal strain - LVGLS). FM was significantly and negatively associated with eating psychopathology (weight and shape concerns, b -0.523, p 0.029; and shape concerns b -0.578, p0.015), while cardiac dysfunction (LVGLS > -18%) was positively associated with dietary restraints (b 1.253, p 0.043). LVEF, in turn, was positively associated with BCM (b 0.721, p 0.008) and FFM (b 0.779, p 0.039). Cardiac dysfunction negatively impacted the effect of nutritional rehabilitation, as those patients reporting reduced LVGLS showed lower FFM (b -4.410, p 0.011), FM (b -1.495, p 0.003) and BCM (b -2.205, p 0.015) at follow-up after three months.

Conclusion: These preliminary results showed that cardiac functioning might represent an early predictor of cachexia and chronicity, while body composition seems to be a more accurate measure for evaluating the recovery process of patients with AN.