Childhood-Onset Eating Disorders
“Childhood-onset eating disorders” refers here to eating disorders with an onset before the age of 14. The term “early onset” is also sometimes used but the usage has led to confusion, since some authors refer to onset in adolescence (i.e., up to 18 years) as “early” to differentiate it from onset in adulthood. We prefer to use the term “childhood-onset” and make a plea for its consistent use for individuals between the ages of 7 and 13 years. (In our experience, 7 years is the youngest age of presentation for patients with anorexia nervosa, and incidence peaks just before 13 years.) Childhood-onset eating disorders are sometimes further grouped according to developmental markers, for example, prepubertal, pubertal, or premenarchal onset.
The eating disorders of childhood include anorexia nervosa, a discussion of which forms the main part of this chapter; bulimia nervosa, rarely seen in clinics in patients under the age of 14 years; food avoidance emotional disorder; selective eating; and pervasive refusal syndrome. (Childhood obesity is discussed in Chapter 77.)
Until relatively recently and despite evidence to the contrary, there has been dispute as to whether “true” anorexia nervosa occurs in childhood. This uncertainty may arise partly from difficulties applying the currently accepted diagnostic criteria for anorexia nervosa. For example, criterion D of the DSM-IV specifies “the absence of at least three consecutive menstrual cycles.” Clearly, in younger girls, it is often inappropriate to consider absence of menses as pathological, since these may not yet have commenced. Furthermore, it is difficult to ascertain whether menstruation might “otherwise have occurred” in girls below the age of 14 years. Also, it is difficult to calculate accurately the expected weight of children who have been failing to grow, since expected weight is usually determined on the basis of height and age.