ICD-11 Criteria for Anorexia Nervosa (6B80)

Anorexia Nervosa is characterised by significantly low body weight for the individual’s height, age and developmental stage that is not due to another health condition or to the unavailability of food. A commonly used threshold is body mass index (BMI) less than 18.5 kg/m2 in adults and BMI-for-age under 5th percentile in children and adolescents. Rapid weight loss (e.g. more than 20% of total body weight within 6 months) may replace the low body weight guideline as long as other diagnostic requirements are met. Children and adolescents may exhibit failure to gain weight as expected based on the individual developmental trajectory rather than weight loss. Low body weight is accompanied by a persistent pattern of behaviours to prevent restoration of normal weight, which may include behaviours aimed at reducing energy intake (restricted eating), purging behaviours (e.g. self-induced vomiting, misuse of laxatives), and behaviours aimed at increasing energy expenditure (e.g. excessive exercise), typically associated with a fear of weight gain. Low body weight or shape is central to the person's self-evaluation or is inaccurately perceived to be normal or even excessive.

6B80.0   Anorexia Nervosa with significantly low body weight

Anorexia Nervosa with significantly low body weight meets all definitional requirements for Anorexia Nervosa, with BMI between 18.5 kg/m2 and 14.0 kg/m² for adults or between the fifth percentile and the 0.3 percentile for BMI-for-age in children and adolescents).

6B80.00   Anorexia Nervosa with significantly low body weight, restricting pattern

Anorexia Nervosa with significantly low body weight, restricting pattern refers to individuals who meet the definitional requirements of Anorexia Nervosa with significantly low body weight and who induce weight loss and maintain low body weight through restricted food intake or fasting alone or in combination with increased energy expenditure (such as through excessive exercise) but who do not engage in binge eating or purging behaviours.

6B80.01    Anorexia Nervosa with significantly low body weight, binge-purge pattern

Anorexia Nervosa with significantly low body weight, binge-purge pattern refers to individuals who meet the definitional requirements of Anorexia Nervosa with significantly low body weight and who present with episodes of binge eating or purging behaviours. These individuals induce weight loss and maintain low body weight through restricted food intake, commonly accompanied by significant purging behaviours aimed at getting rid of ingested food (e.g. self-induced vomiting, laxative abuse or enemas). This pattern also includes individuals who exhibit binge eating episodes but do not purge.

6B80.0Z  Anorexia Nervosa with significantly low body weight, unspecified

6B80.1    Anorexia Nervosa with dangerously low body weight

Anorexia Nervosa with dangerously low body weight meets all definitional requirements for Anorexia Nervosa, with BMI under 14.0 kg/m² in adults or under the 0.3rd percentile for BMI-for-age in children and adolescents. In the context of Anorexia Nervosa, severe underweight status is an important prognostic factor that is associated with high risk of physical complications and substantially increased mortality.

6B80.10    Anorexia Nervosa with dangerously low body weight, restricting pattern

Anorexia Nervosa with dangerously low body weight, restricting pattern refers to individuals who meet the definitional requirements of Anorexia Nervosa with dangerously low body weight and who induce weight loss and maintain low body weight through restricted food intake or fasting alone or in combination with increased energy expenditure (such as through excessive exercise) but who do not engage in binge eating or purging behaviours.

6B80.11   Anorexia Nervosa with dangerously low body weight, binge-purge pattern

Anorexia Nervosa with dangerously low body weight, binge-purge pattern refers to individuals who meet the definitional requirements of Anorexia Nervosa with dangerously low body weight and who present with episodes of binge eating or purging behaviours. These individuals induce weight loss and maintain low body weight through restricted food intake, commonly accompanied by significant purging behaviours aimed at getting rid of ingested food (e.g. self-induced vomiting, laxative abuse or enemas). This pattern also includes individuals who exhibit binge eating episodes but do not purge.

6B80.1Z     Anorexia Nervosa with dangerously low body weight, unspecified

6B80.2      Anorexia Nervosa in recovery with normal body weight

Among individuals who are recovering from Anorexia Nervosa and whose body weight is more than 18.5 kg/m2 for adults or over the fifth percentile for BMI-for-age for children and adolescents, the diagnosis should be retained until a full and lasting recovery is achieved, as indicated by the maintenance of a healthy weight and the cessation of behaviours aimed at reducing body weight independent of the provision of treatment (e.g., for at least 1 year after intensive treatment is withdrawn).

6B80.Y   Other specified anorexia Nervosa

6B80.Z    Anorexia Nervosa, unspecified

REFERENCE:

International Classification of Diseases Eleventh Revision (ICD-11). Geneva: World Health Organization; 2022. License: CC BY-ND 3.0 IGO.

https://creativecommons.org/licenses/by-nc-nd/3.0/igo/