Leptin concentration indexed to fat mass is increased in untreated anorexia nervosa (AN) patients

Data regarding serum adipocytokine and ghrelin concentrations in different stages of anorexia nervosa (AN) is conflicting.

Our aim is to determine serum concentrations of adiponectin (ApN), leptin and ghrelin in different stages of AN and to evaluate their relationships with study parameters.

Study group was composed of four subgroups: Group 1: patients with a recent diagnosis of AN (n = 19); group 2: weight recovered (10% increase in body weight compared with baseline) subgroup of group 1 during follow-up (n = 10); group 3: recovered patients with a previous history of AN but normal menstrual cycles and body weight currently (n = 10); group 4: control group (n = 10). Venous blood was obtained for measurements of biochemical/hormonal parameters, ApN, leptin and ghrelin. Body composition was determined by bioimpedance analysis.

Changes in adipocytokine and ghrelin concentrations and relationships with anthropometric/biochemical parameters.

Leptin: fat mass (kg) ratio was significantly higher in group 1 patients compared with group 4 (4.3 +/- 4.6 vs. 1.1 +/- 0.5 microg/l kg, P < 0.01). No significant difference was observed among ghrelin concentrations. Leptin showed significant positive correlation with body fat mass in all groups. ApN showed significant positive association with body mass index in Group 1.

Leptin concentrations indexed to fat mass may indicate a nonphysiological higher set point of leptin per unit fat mass in treatment-naive AN patients. Correlation pattern between ApN and fat mass is modified also. Altered adipocytokine profile in AN may contribute to anorectic behaviour.