Aetiological factors

This condition is the result of a combination of individual predisposing factors and social factors that encourage 'thinness' as a desirable social attribute:

• genetic factors:
  • parents with established anorexia have children with a higher than average incidence of anorexia nervosa
  • twin studies support a genetic contribution
    
    
    
    
• hypothalamic dysfunction:
  • if amenorrhoea occurs before any loss in weight then this suggests that the anorexia is a result of hypothalamic-pituitary dysfunction
    
    
• social factors
  • the incidence of anorexia nervosa is higher in middle and upper classes where there is more concern about body weight
  • certain professions e.g. ballet dancers, and sports e.g. gymnastics and middle distance runners, have a higher incidence of anorexia nervosa
    
    
• psychological causes:
  • Birch (1974) saw anorexia nervosa as 'a struggle for control, for a sense of identity and effectiveness with the relentless pursuit of thinness as a final step in this effort'
  • childhood temperament and personality traits such as perfectionism, rigidity, drive for thinness, and obsessive-compulsive traits may predispose to the development of anorexia nervosa during adolescence. Puberty and associated brain changes may further increase this risk (1)
    
    
• family factors:
  • Kalucy (1977) showed that many families of anorexic children show an unusual interest in physical appearance and food

Reference:

• (1) Kaye WH et al. New insights into symptoms and neurocircuit function of anorexia nervosa. Nat Rev Neurosci. 2009;10(8):573-84