New concepts in anorexia nervosa.

Anorexia nervosa (AN), a psychosomatic disorder, has serious negative effects on multiple organs and systems of the human body. A large number of endocrine and metabolic anomalies have been described, including amenorrhea/oligomenorrhea, delayed puberty, hypothyroidism, hypercortisolism, and alterations in the growth hormone (GH) axis and bone metabolism. The role of different peptides, including ghrelin, leptin, neuropeptide Y and serotonin, in the regulation of appetite is discussed. In addition, isolated hypogonadotropic hypogonadism that occurs in these patients is analyzed in detail, as well as the abnormalities in the growth hormone axis. Alterations in bone mineral density, bone markers and the degree of osteopenia in these patients, depending on the age at which amenorrhea began and its duration, are also discussed. Finally, our current understanding of the possible benefits of treatment with estrogens and progestogens is also analyzed.