Eating Disorders in Children and Adolescents
Eating Disorders in Children and Adolescents
Eating problems are common in children and adolescents, and eating disorders typically have their onset during these developmental periods.1 Anorexia nervosa is a serious and potentially life-threatening disorder associated with severe food restriction, overexercise, malnutrition, and distorted thinking about body shape and weight. The typical age of onset is early adolescence (ages 12 to 15 years). Bulimia nervosa is characterized by periods of restriction followed by binge eating and purging behaviors (eg, vomiting, laxative use, overexercise) and often begins during middle adolescence (ages 15 to 17 years). A variety of social, developmental, genetic, and familial factors have been implicated in the etiology of these disorders, but their cause is unknown.
In younger children, a range of eating disorders has been identified that includes atypical syndromes, such as selective eating and food avoidance emotional disorder (FAED).2 These atypical disorders are diagnosed as eating disorders not otherwise specified (EDNOS) in the current DSM. These disorders typically occur in school-aged children. Children with selective eating are highly sensitive to taste, texture, and amounts of food and have an extraordinarily narrow range of acceptable foods they will eat.3 These syndromes often lead to social, behavioral, and nutritional problems.
Food neophobia may be primary (eg, never learned to eat a range of food), or it may occur in response to an adverse event (eg, choking, vomiting, diarrhea). Selective eating is associated with general anxiety and with autism spectrum disorders. Children with FAED are underweight, do not report shape and weight concerns, and often have somatic complaints (eg, stomachaches). In contrast to patients with anorexia nervosa, those with FAED usually recognize that they are too thin and want to gain weight.4
Identification and diagnosis of eating disorders in children and adolescents is a major problem (Table 1). As with many psychiatric disorders, diagnostic classifications of eating disorders in DSM are not developmentally sensitive. Current criteria are appropriate for adults with long-standing disorders. For example, in anorexia nervosa, the requirement of weight loss to a suggested level of 85% of expected weight for height is challenging when applied to a growing child, even when using best estimates for age.5 In addition, the criteria for reporting fear of weight gain requires that young adolescents make verbal statements attesting to this fear; however, many do not connect their behaviors with the emotion of fear. At the same time, their scrupulously avoidant and restrictive eating habits and their reactions to attempts to make them eat are more articulate than the words they speak.2
In children with bulimia nervosa, the availability and opportunity to binge eat and purge is constrained by family, school, and other environmental processes that may artificially limit these activities. For these reasons, the behavioral thresholds set for these disorders are difficult to apply to this age-group.6 Consequently, the majority (approximately 60%) of children and adolescents are given a diagnosis of EDNOS.7 This heterogeneous categorization leads to confusion about the diagnosis and problems in specifying treatment, and it sometimes prohibits insurance coverage.
Research studies on treatment of eating disorders have generally lagged behind those of disorders of similar severity and incidence. In the adult literature, there are 9 published randomized controlled studies of psychosocial treatments for anorexia nervosa with fewer than 900 participants.8 Attrition rates averaged 50% in these studies, and no psychosocial treatment was found to be effective. Psychopharmacological studies of anorexia nervosa are also few and consist of small pilot comparisons with no evidence that medications are useful for the disorder.9
There are 6 randomized clinical trials for anorexia nervosa in children and adolescents, with fewer than 400 participants studied.8 However, family therapy was examined in 5 of these trials, and data suggest that family therapy is useful for this age-group. On average, between 60% and 80% of adolescents who are treated with family therapy no longer meet diagnostic criteria for anorexia nervosa, while between 40% and 60% reach normal weight for their age and have no evidence of eating-related psychopathology.10
No randomized clinical trials of medications for adolescents with anorexia nervosa have been published. A number of small studies of antidepressants and newer atypical antipsychotics suggest that these medications may be useful for secondary anxiety and distress, as well as for promoting short-term weight gain. Long-term benefits are unknown, however.11
For adults with bulimia nervosa, cognitive-behavioral therapy (CBT) has been shown to be more effective than placebo, medications, and several other forms of psychotherapy.12 Rates of recovery (ie, no binge eating or purging for 28 days) are about 35% with CBT, although there are much greater declines in rates (approximately 50% to 80%) of binge eating and purging even among those who do not recover. However, there are only 2 published randomized clinical trials in adolescents with bulimia nervosa.13,14
The first of those 2 studies compared a self-help version of CBT with family therapy in 80 adolescents with bulimia nervosa or partial bulimia nervosa.14 There were no differences in outcome between the 2 groups: 40% of those in both groups recovered at follow-up, but guided self-help was more cost-effective than family therapy in that study.
The second study compared family therapy with individual therapy in 80 adolescents with bulimia nervosa or partial bulimia nervosa.13 Family therapy was found to be superior to individual therapy at the end of treatment and follow-up. Rates of recovery (as defined above) at follow-up were 30% for those in family therapy and 10% for those who received individual therapy.