Free and bound plasma leptin in anorexia nervosa patients during a refeeding program

Anorexia nervosa (AN) has a complex pathophysiology, involving heterogeneous environmental and genetic factors, and is not associated to validated biomarkers for diagnosis and follow-up or outcome. Although the evaluation of changes of plasma biochemical markers, such as reproductive and thyroid hormones, adipokines and ghrelin, in AN may reflect the disnutritional condition rather than specific features of the disease [1], the combination of eating disorder and amenorrhea led to hypothesize the involvement of leptin or leptin-related mechanisms in the pathophysiology and the maintenance of this psychiatric syndrome [2, 3]. In AN patients, serum leptin levels are lower than in age-matched controls [4] and increase upon weight gain, together with a reduction of soluble leptin receptor [5]. The present study was aimed at evaluating the changes of plasma leptin in its free (FL) and soluble receptor-bound (BL) fractions and their relationship with body weight gain in AN patients undergoing a refeeding/ rehabilitation program. Materials and methods