The eating disorders, anorexia nervosa and bulimia nervosa, may be classified as true psychosomatic illnesses, inasmuch as an underlying biological vulnerability interacts with a particular cultural stress in order to produce behavioral and psychological symptoms. For example, anorexia and bulimia nervosa are more prevalent in industrialized societies, where there is an overabundance of food and where attractiveness in women is linked with being thin, than in agriculturally-based societies. Immigrants from cultures in which anorexia nervosa is rare are more likely to develop the illness as they assimilate the ideals of a thin body appearance.
DSM-IV-TR Diagnostic Criteria
Refusal to maintain body weight at or above a minimally normal weight for age and height (e.g., weight loss leading to maintenance of body weight less than 85% of that expected; or failure to make expected weight gain during a period of growth, leading to body weight less than 85% of that expected).
Intense fear of gaining weight or becoming fat, even though underweight.
Disturbance in the way in which one's body weight or shape is experienced, undue influence of body weight or shape on self-evaluation, or denial of the seriousness of the current low body weight.
In postmenarcheal females, amenorrhea, i.e., the absence of at least three consecutive menstrual cycles. (A woman is considered to have amenorrhea if her periods occur only following hormone, e.g., estrogen, administration.)
- Restricting type: during the current episode of anorexia nervosa, the person has not regularly engaged in binge-eating or purging behavior (i.e., self-induced vomiting or the misuse of laxatives, diuretics, or enemas).
- Binge-eating/purging type: during the current episode of anorexia nervosa, the person has regularly engaged in binge-eating or purging behavior (i.e., self-induced vomiting or the misuse of laxatives, diuretics, or enemas).
(Reprinted, with permission, from Diagnostic and Statistical Manual of Mental Disorders, 4th edn, Text Revision. Copyright 2000 American Psychiatric Association.)
In some ways, the term anorexia nervosa is a misnomer, because the affected individual's appetite and craving for food are usually preserved. Nevertheless, the individual will actively counter the feelings of hunger with disordered thinking, leading to self-imposed starvation. The threshold for defining the amount of weight loss considered to be serious enough to qualify for the diagnosis of anorexia nervosa is computed on the basis of the Metropolitan Life Insurance tables or pediatric growth charts. A body mass index less than or equal to 17.5 kg/m2 (calculated as weight in kilograms/height in meters2) represents an alternative guideline accepted by many researchers. Nevertheless, these standards are only suggested guidelines, and clinicians should also consider the individual's body build and weight history.
Lifetime prevalence rates for anorexia nervosa in females are approximately 0.5–1.0, or 1 in 100–200 individuals. Many more individuals exhibit symptoms that do not meet the ...