Body composition, eating disorder psychopathology, and psychological distress in anorexia nervosa: a longitudinal study

Abstract

Although the effect of immediate weight restoration on body composition and body fat distribution has previously been studied in anorexia nervosa (AN), its influence in women with AN on eating disorder psychopathology and psychological distress has not previously been investigated to our knowledge. We assessed body composition and fat mass distribution before and after body weight restoration and investigated any relation between changes in body fat patterns of patients with AN treated in a specialist inpatient unit and their eating disorder and psychological distress features. Body composition was measured by using dual-energy X-ray absorptiometry in 50 female, adult patients with AN before and after complete weight restoration [body mass index (BMI; in kg/m²) ≥18.5] and 100 healthy control subjects matched by age and posttreatment BMI of study group participants. Eating disorder psychopathology and psychological distress were assessed in the AN group before and after weight restoration by using the Eating Disorder Examination interview and the Global Severity Index of the Brief Symptom Inventory (BSI-GSI), respectively. After the achievement of complete weight restoration, patients with AN had higher trunk (P < 0.001), android (P < 0.001), and gynoid (P < 0.001) fat masses and lower arm (P < 0.001) and leg (P = 0.001) fat masses with respect to control subjects. No relation was shown between body-composition variables and eating disorder psychopathology in the AN group, and the only significant predictor of change in BSI-GSI was the baseline BSI-GSI score. The normalization of body weight in patients with AN is associated with a preferential distribution of body fat in central regions, which does not, however, seem to influence either eating disorder psychopathology or psychological distress scores.