Irreversibility of cardiac autonomic dysfunction in female adolescents diagnosed with anorexia nervosa after short- and long-term weight gain.

Anorexia nervosa (AN) patients may present with cardiac autonomic system dysfunction. Power spectral analysis of heart rate variability (HRV) is a reliable noninvasive examination for the quantitative assessment of the central sympathovagal interaction that modulates cardiovascular autonomic function. In the present study, HRV parameters were assessed in female adolescent AN inpatients in the malnourished phase at admission, at discharge when achieving weight restoration, and 24-36 months after discharge, when considered remitted. Nineteen normal-weight female controls were similarly assessed. Spectral analysis of HRV was done with the fast Fourier transform algorithm. At admission and discharge, patients underwent routine laboratory examinations and responded to questionnaires assessing eating-related preoccupations, behaviors, and personality attributes, depression and anxiety. Compared with the controls, AN patients had significantly lower heart-rate and HRV, lower total power and low frequency components, elevated high frequency components, and decreased low to high frequency power ratio as assessed with the power spectral analysis at all three evaluation points. These disturbances were not correlated with the baseline laboratory and psychometric measures. Our preliminary findings suggest that female adolescent AN inpatients may have a cardiovascular autonomic dysfunction in the form of vagal abnormality present not only in malnourished patients, but also persisting following short-term and long-term weight restoration.

Modulation of adiponectin and leptin during refeeding of female anorexia nervosa patients.

CONTEXT: Several studies assessed adiponectin levels in anorexia nervosa (AN) patients, however, data regarding the dynamics of changes in adiponectin levels during refeeding of these patients is limited and contradicting. OBJECTIVE: Our objective was to assess adiponectin levels and the distribution of its different isoforms in AN patients before and after long-term refeeding, and to relate them to alterations in body mass index, leptin, insulin sensitivity, and additional endocrine parameters. DESIGN, SETTING, AND PARTICIPANTS: We conducted a longitudinal controlled study of 38 female adolescent malnourished AN inpatients, with 13 young, lean, healthy women serving as controls. Blood samples were obtained upon admission and thereafter at 1, 3, and 5 months (at target weight). MAIN OUTCOME MEASURES: Changes in body mass index, leptin, adiponectin, insulin sensitivity, and adiponectin multimeric forms were measured. RESULTS: At admission, leptin levels of AN patients were significantly lower, whereas insulin sensitivity (assessed by homeostasis model assessment-insulin resistance), adiponectin levels, and the ratio of high molecular weight (HMW) adiponectin to total adiponectin were significantly higher compared with controls. During weight recovery, leptin levels and homeostasis model assessment-insulin resistance increased significantly, whereas adiponectin and HMW adiponectin/total adiponectin ratio decreased significantly, to levels similar to controls. An initial increase in adiponectin levels was observed after 1 month of refeeding. There was no correlation between adiponectin and either T(4) or cortisol levels. CONCLUSIONS: Our study demonstrates hyperadiponectinemia, increased adiponectin HMW isoform, and increased insulin sensitivity in adolescent AN female patients and reversal of these findings with weight rehabilitation. We hypothesize that increased adiponectin levels may have a protective role in maintaining energy homeostasis during extreme malnourishment.