Anorexia nervosa (AN) – colloquially called anorexia nervosa – (synonyms: Anorectic syndrome; anorexia mentalis; anorexia; dysorexia; endogenous anorexia; voluntary starvation n.e.c. ; psychogenic anorexia; psychogenic aphagia; psychogenic lack of appetite; pubertal anorexia; ICD-10-GM F50.0: Anorexia nervosa; ICD-10-GM F50.1: Atypical anorexia nervosa) belongs to the psychogenic eating disorders. People suffering from anorexia nervosa want to be extremely thin. The criteria of a healthy, complete and varied diet are not met by these patients. Anorexia nervosa is classified according to different models:
- First, according to the criteria of the American Psychiatric Association (APA), anorexia nervosa is considered to exist when the weight of the affected person is less than 85% of the weight that would be expected in healthy individuals.
- According to the ICD-11 classification (International Classification of Diseases) applicable in Europe, adults from a BMI (body mass index) of < 18.5 kg/m² (corresponds to falling below the fifth BMI age percentile in children and adolescents) is spoken of anorexia nervosa.
Other criteria of anorexia nervosa include:
- Self-inflicted weight loss
- Body schema disorder
- Endocrine disorders (hormonal disorders)
In addition, there are several subgroups of anorexia nervosa:
- Atypical anorexia nervosa (ICD-10-GM F50.1) – this refers to a form of anorexia nervosa in which not all criteria for the disease are met
- Restrictive anorexia nervosa – this includes patients who lose weight by restricting their food intake and excessive physical activity
- Anorexia nervosa of the “binge eating/purging” subtype – this form of the disease is characterized by binge eating, as well as self-inflicted vomiting and laxative (laxative) abuse
- Childhood anorexia nervosa – in this form, children are affected before puberty; there is a delay in development and growth in this case.
Sex ratio: males to females is 1: 8-10 (in adults); in children, less sex differences.
Frequency peak: the disease mostly affects girls in puberty (age peak 14 years) and young women who are very concerned with their appearance and body. The prevalence (disease incidence; here, lifetime prevalence) is 1% in women (peak of manifestation at age 18 years) and <0.5% in men. The prevalence of anorexia nervosa has increased in recent years. In addition, younger and younger girls and increasingly boys and men are affected. Course and prognosis: The disease progresses over several years. The effects of anorexia nervosa are severe and affect both physical and mental health. School or work performance is also affected.During the first two years of the disease, recovery is rare. The risk of chronicity of the disease is high. In about 60% weight normalization after 5-6 years. Only 50-70% of patients are cured by therapy. With first disease in puberty up to 17 years, there is the most favorable prognosis. With very early and late onset, the prognosis is negative. According to a long-term study, most patients recover from their eating disorder in adulthood: 22 years since the start of the study, the number of women free of symptoms of anorexia nervosa has increased significantly: 62.8% of patients have recovered from the eating disorder, i.e. have been symptom-free for at least one year. In a long-term Swedish study, one in five continued to have eating disorders 30 years after onset. The 12-year lethality (mortality related to the total number of people with the disease) is approximately 10%. Mortality (number of deaths in a given period, relative to the number of the population in question) is 5-6% per decade; 5.1 per 1,000/yr. Comorbidities (concomitant disorders): anorexia nervosa is increasingly associated with other mental disorders such as personality disorders and addictive disorders (alcohol dependence or abuse). The lifetime prevalence for the development of depression in anorexia nervosa patients is about 40 %, for obsessive-compulsive disorders between 15 and 69 %.Approximately 60% of anorexia nervosa patients have comorbidity with anxiety disorders.
