Distribution and clinical comparison of restrictive feeding and eating disorders using ICD-10 and ICD-11 criteria

Abstract

Objective: Within the eleventh edition of the International Classification of Diseases (ICD-11), diagnostic criteria for feeding and eating disorders were revised and new diagnoses including avoidant/restrictive food intake disorder (ARFID) are classifiable; however, nothing is known about how these changes affect the prevalence of feeding and eating disorders. This study compared the distribution and clinical characteristics of restrictive feeding and eating disorders between ICD-10 and ICD-11.

Method: The Eating Disorder Examination (EDE), its child version, and the EDE ARFID module were administered to N = 82 patients (0-17 years) seeking treatment for restrictive feeding and eating disorders and their parents. Clinical characteristics were derived from medical records, questionnaires, and objective anthropometrics.

Results: The number of residual restrictive eating disorders (rrED) significantly decreased from ICD-10 to ICD-11 due to a crossover to full-threshold disorders, especially anorexia nervosa (AN) or ARFID. Patients reclassified to ICD-11 ARFID were younger, had an earlier age of illness onset, more restrictive eating behaviors, and tended to have more somatic comorbidities compared to those reclassified to ICD-11 AN. Patients with rrED according to both ICD-10 and ICD-11 were younger, had an earlier age of illness onset, less shape concern, and more somatic comorbidities than patients who were reclassified from ICD-10 rrED to ICD-11 AN or ARFID.

Discussion: This study highlights the inclusive approach of ICD-11 criteria, paving the way for more targeted treatment, and ARFID's high clinical relevance. Future studies considering nonrestrictive feeding and eating disorders across the life span may allow further analyses on diagnostic crossover.

Public significance: Changes in diagnostic criteria for restrictive eating disorders within the newly published ICD-11 led to an increase in full-threshold disorders, while the number of rrED was significantly lowered compared to ICD-10 criteria. The results thus highlight the diagnostic utility of ICD-11 criteria and may help providing adequate treatment to children and adolescents with rrED.

Keywords: ICD-10; ICD-11; anorexia nervosa; avoidant/restrictive food intake disorder; classification; comparisons; diagnostic crossover; distribution; residual restrictive eating disorders; restrictive eating disorders.