Treatment response in children and adolescents with anorexia nervosa: a naturalistic, case–control study

Purpose Although a few recent articles describe adults with treatment-resistant anorexia nervosa (TR-AN), no study addresses the specific features of subjects not responding to treatment in the developmental age. This study reports on the clinical and psychopathological variables that distinguish children and adolescents who did not respond to treatment (here “TR-AN”) from good-outcome controls, in a multidisciplinary hospital treatment setting. Methods Naturalistic, case–control study conducted on individuals showing lack of response to treatment and good-outcome controls. TR-AN was defined as two or more incomplete admissions and no complete admissions, consistently with studies in adults. Good-outcome was defined as complete first admission, availability for follow-up visit after 6 months, and maintain- ing at follow-up a %BMI > 70% in the absence of binging or purging in the preceding 3 months. Psychopathological (Eating Disorders Inventory-3 EDI-3; Beck Depression Inventory-II), clinical, and treatment variables at admission were compared. Significant differences in the univariate analyses were included in an exploratory binary logistic regression. Results Seventy-six patients (30 TR-AN, 46 good-outcome AN controls) were enrolled (mean age 14.9±1.9 years, F = 94.7%). TR-AN individuals had a higher age at admission and higher EDI-3 Eating Disorder Risk (EDRC) scores, were treated less frequently with a nasogastric tube (NGT), and achieved a lower BMI improvement at discharge than good- outcome controls. A predictive model for TR-AN status was found (X2 = 19.116; Nagelkerke-R2 = 0.478, p < 0.001), and age at admission (OR = 0.460, p = 0.019), EDI-3 EDRC (OR = 0.938, p = 0.043), and NGT (OR = 8.003, p = 0.019) were associated with a TR-AN status. Conclusions This is the first report on the psychopathological and clinical characteristics of children and adolescents not responding to treatment. These patients showed higher age and eating disorder scores, and were less frequently fed with NGT than controls. Despite the multiple incomplete admissions of our subjects, the short included follow-up limits the pos- sibility for direct comparisons with adult samples of treatment-resistant patients. Thus, the specific features of children and adolescents with TR-AN should be assessed in longitudinal studies.