Anorexia Nervosa: Causes

Pathogenesis (development of disease)

The origin of anorexia nervosa is not yet fully understood. Several factors play a role. Primarily, neurochemical, metabolic, and hormonal changes are discussed. In addition to genetic disorders (see “Genetic burden” below) of the serotonergic (affecting serotonin levels) system, psychosocial and social factors seem to play a major role:

• Psychosocial factors:
  • Rejection of the female role
  • Need for control
• sociocultural factors:
  • Western ideal of thinness and performance (→ problem of identification with one’s own body).

A psychogenic component is usually found in childhood, especially disturbed relationships with one or both parents. The affected person thereby becomes a symptom carrier for family problems.

Etiology (causes)

Biographical causes

• Genetic load from parents, grandparents – concordance in monozygotic twins up to 50%!
  • Genome-wide association study (GWAS) found eight gene variants linking eating disorder to metabolic disorders (type 1 diabetes or other autoimmune disorders) and to other psychiatric disorders (anxiety, depression, schizophrenia, and obsessive-compulsive disorder).
• Age – puberty
• Childhood obesity
• Homo- and bisexuality in men
• Professions – professional groups such as ballet dancers, models, athletes (sports anorexia; especially in aesthetic-compositional sports such as rhythmic gymnastics or synchronized swimming – but also ski jumpers and some endurance athletes).

Behavioral causes

• Nutrition
  • Recurrent dieting behavior
  • Restrained eating behavior
• Psycho-social situation
  • Fear of obesity
  • Fear of being overworked
  • Experiences of loss and rejection
  • Emotional neglect
  • Family factors such as overprotection and conflict avoidance.
  • Family problems or conflicts with peers.
  • Lack of self-esteem
  • Physical abuse in the past
  • Low self-esteem
  • Perfectionism
  • Psychiatric disorders such as depression in the family environment.
  • Sexual abuse
  • Dissatisfaction with one’s appearance (self-esteem issues).
  • Compulsive, perfectionist character

Disease-related causes

• Diabetes mellitus type 2 – diabetes, which occurs predominantly in childhood and adolescence.

Medications that can be the cause of a loss of appetite

• Anthelmintics (diethylcarbamazine).
• Antidepressants
  • Selective serotonin reuptake inhibitors (SSRIs) – fluoxetine
• Antiepileptic drugs (topiramate).
• Antibiotics
  • Cotrimoxazole
  • Macrolides (spiramycin)
• Antiviralia (amantadine)
• Folic acid antagonist (methotrexate)
• Fusion inhibitors (enfuvirtide).
• Immunosuppressants (azathioprine, ciclosporin (cyclosporin A), mercaptopurine).
• Immunotherapeutics (mitoxantrone).
• Levodopa (L-dopa)
• Muscle relaxants (baclofen)
• Neurokinin antagonists (aprepitant, fosaprepitant).
• Non-opioid analgesics (flupirtine).
• Nonbenzodiazepines (zaleplon, zolpidem, zopiclone, zaleplon).
• Uricosurics (probenecid, benzbromarone).

Other causes

• Slimness mania of society