title: Elevated physical activity and low leptin levels co-occur in patients with anorexia nervosa.
abstract: Low leptin levels are an endocrinological hallmark of acute anorexia nervosa (AN); a subthreshold leptin secretion in adipocytes as a consequence of a reduced energy intake is presumed to be the major trigger of the adaptation of an organism to semistarvation. The aim of the current study is to define symptoms of AN that are potentially linked to low leptin levels. For this purpose, quantitative somatic and psychopathological variables were obtained in 61 inpatients with acute AN (study group 1) upon referral for inpatient treatment, and they were concomitantly blood sampled to allow determination of serum leptin levels. Correlations between these variables and logarithmic transformed (lg10) leptin levels were descriptively assessed. Apart from the well-known correlations between leptin levels and anthropometric measurements, the strongest correlation was observed between lg10 serum leptin levels and expert ratings of motor restlessness (r = -0.476; nominal P = 0.003) upon use of visual analog scales. We thus generated the hypothesis that physical activity levels in AN patients are related to serum leptin levels. This hypothesis was tested in an independent study group of 27 adolescent inpatients (study group 2) who were also assessed upon referral. Physical activity levels, which, in this study group, were assessed with the activity module of the expert rating form of the Structured Inventory for Anorexic and Bulimic Syndromes, were significantly correlated with lg10 leptin levels (r = -0.51; one-sided P = 0.006). A regression model based on the independent variables body mass index and lg10 leptin levels explained 37% of the variance of physical activity (R(2) = 0.37; P = 0.003); only the lg10 leptin levels contributed significantly to the variance (P = 0.003). Our results suggest that, similar to semistarvation-induced hyperactivity in rats, hypoleptinemia in patients with AN may be one important factor underlying the excessive physical activity.
authors: Department of Child and Adolescent Psychiatry and Psychotherapy, Aachen University, D-52074 Aachen, Germany.
authors: Kristian
authors: K
authors: Holtkamp
authors: Beate
authors: B
authors: Herpertz-Dahlmann
authors: Claudia
authors: C
authors: Mika
authors: Martina
authors: M
authors: Heer
authors: Nicole
authors: N
authors: Heussen
authors: Manfred
authors: M
authors: Fichter
authors: Stephan
authors: S
authors: Herpertz
authors: Werner
authors: W
authors: Senf
authors: Werner F
authors: WF
authors: Blum
authors: Ulrich
authors: U
authors: Schweiger
authors: Andreas
authors: A
authors: Warnke
authors: Anne
authors: A
authors: Ballauff
authors: Helmut
authors: H
authors: Remschmidt
authors: Johannes
authors: J
authors: Hebebrand
mesh_terms: D000208:Acute Disease; D000222:Adaptation, Physiological; D000293:Adolescent; D000328:Adult; D000856:Anorexia Nervosa / Q000097:blood* / Q000150:complications / Q000503:physiopathology*; D002648:Child; D005260:Female; D006801:Humans; D020738:Leptin / Q000097:blood*; D009043:Motor Activity; D011595:Psychomotor Agitation / Q000097:blood* / Q000209:etiology / Q000503:physiopathology*
chemical_list: D020738:Leptin