Eating Disorders
Rosemary Calderon PhD
Introduction
Anorexia nervosa and bulimia nervosa are two of the most challenging disorders afflicting children and adolescents, with the potential for serious impact on both physical and psychological development. Anorexia nervosa has been documented by historians for many centuries. For example, “Holy Anorexia” was used to describe the severe fasting and self-initiated purging among those aspiring for sainthood during the medieval period. In modern medical history, there is a debate regarding first descriptions of currently defined anorexia nervosa. Bulimia nervosa has been described for an even longer time than severe restricting behaviors. The ancient Egyptians purged for “health” reasons. Binge eating and purging by the Roman upper class is well documented, most notably by Emperors Claudius and Vitellius. In modern times, Gerald Russell, a British psychiatrist, first described bulimia nervosa as a distinct syndrome in 1979. Current understanding hypothesizes that broad cultural forces and social stressors meld with individual biomedical and psychological factors to put an increasing number of young women and men at risk of developing eating disorders.
Clinical Features
Signs and Symptoms
Core features that define anorexia nervosa and bulimia nervosa as defined in the American Psychiatric Association’s (1994) Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition are summarized in Table 13-1.
For anorexia nervosa, the first core feature and hallmark of the disorder is significant weight loss or failing to gain weight commensurate with height. The second core feature is an intense fear of gaining weight or becoming fat. Individuals with anorexia struggle with the idea of eating and think that anything but the most stringent control of their food intake will result in undue weight gain. The primary distortion is these youths’ perceptions of themselves as overweight despite their emaciated state. Even those youth who achieve remission often continue to perceive themselves as overweight. The third core feature is amenorrhea, defined as three consecutive missed menstrual cycles, in postmenarchal women. Obviously, this last feature does not apply to premenarchal girls or to boys. Though not part of the DSM-IV criteria, rigid thinking, perfectionism, and preference for predictability are common in youth with anorexia.
Individuals with anorexia nervosa can be further classified as those who are primarily restricting, meaning that they achieve their weight loss by limiting caloric intake, and those who both restrict and engage in binge eating and/or purging. The binging and purging subtype of anorexia nervosa is distinct from the binge eating and purging of bulimia nervosa in that restricting, weight loss, and low weight are the presenting concerns. Adolescent females remain the predominant population with anorexia nervosa but males and younger children are becoming more commonly affected.
TABLE 13-1 Comparing DSM-IV-TR Diagnostic Criteria for Anorexia Nervosa and Bulimia | ||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ||||||||||||||||||||||||||||
The chief differentiating factor between bulimia nervosa and anorexia nervosa is the absence of severe weight loss, that is, those with bulimia are above 85% of their ideal weight and often slightly overweight. It is estimated that approximately 50% of those with anorexia become bulimic. The diagnostic criteria for bulimia nervosa focus primarily on two components: binge eating and an inappropriate compensatory action to prevent weight gain. Binge eating
is defined as eating substantially more than a regular person would eat in a 2-hour period on at least two occasions per week for 3 months. The binges may consist of any food, but tend to be of high-sugar and high-carbohydrate content, for example, cake and ice cream. These episodes of binge eating are typically associated with a sense of loss of control and often occur following an unpleasant experience involving an injury to self-esteem. The individual usually feels ashamed during a binging episode and immediately afterwards. Engagement in some other activity to “undo” the binge is common, such as self-induced vomiting and less commonly misuse of laxatives, enemas, or diuretics. For individuals with the nonpurging subtype, compensatory behaviors may include excessive exercising, subsequent fasting or restricting, the misuse of appetite suppressants or thyroid hormone to speed metabolism or, in diabetics, deliberately missing insulin doses in order to avoid weight gain.
is defined as eating substantially more than a regular person would eat in a 2-hour period on at least two occasions per week for 3 months. The binges may consist of any food, but tend to be of high-sugar and high-carbohydrate content, for example, cake and ice cream. These episodes of binge eating are typically associated with a sense of loss of control and often occur following an unpleasant experience involving an injury to self-esteem. The individual usually feels ashamed during a binging episode and immediately afterwards. Engagement in some other activity to “undo” the binge is common, such as self-induced vomiting and less commonly misuse of laxatives, enemas, or diuretics. For individuals with the nonpurging subtype, compensatory behaviors may include excessive exercising, subsequent fasting or restricting, the misuse of appetite suppressants or thyroid hormone to speed metabolism or, in diabetics, deliberately missing insulin doses in order to avoid weight gain.
While bulimia is predominantly found in young women, it has a higher prevalence in males than anorexia nervosa. This is thought to be attributed to male competitive sports that require specific body measures or weigh-ins (e.g., wrestling). Individuals with bulimia may have poor dentition or halitosis from repeated self-induced emesis. They may also be engaged in other pathologic behaviors that will become apparent on examination or during interview, such as substance abuse which may be identified only on urine toxicology, or self-mutilation which may be evident as scarring on the arms, abdomen, hips, or thighs (more common in women but increasingly common in males). Individuals with either bulimia or anorexia tend to avoid eating with others, preferring privacy and often provide numerous reasons for not eating with others.
Eating disorders not otherwise specified (ED NOS) comprise the largest category for eating disorders as they include all subthreshold presentations of anorexia nervosa and bulimia nervosa.
Diagnostic and Developmental Issues
It is interesting to note that anorexia nervosa, binge/purge subtype, and bulimia nervosa are separated solely by the fact that the adolescent with anorexia is underweight. Indeed, with the trend toward rethinking of psychiatric disorders on a continuum, it is likely that these nosologic categories will undergo further adjustment for the DSM-V, scheduled for publication in 2010.
The challenge of accurate evaluation and diagnosis of anorexia nervosa is compounded in younger patients by several factors. A young patient may be gaining weight, however, not at a rate appropriate to height. Anorexia nervosa in prepubertal children is further complicated by the fact that prepubertal youth have less body fat, are more prone to volume depletion, are more likely to fluid restrict, and are more difficult to engage in the interview, and in later treatment, because of their cognitive limitations. Younger girls may not have started their menses or established a routine pattern of menses. Therefore, the third diagnostic criteria of missing three menstrual periods may not always apply. Younger patients and males may also not have the same level of body distortion or intense fear of becoming fat. Thus, a developmental framework is needed when diagnosing and treating younger or male youth.
Epidemiology
Eating disorders are among the most serious psychiatric disorders in terms of morbidity and mortality. Over a 30-year period, approximately 15% to 20% of individuals with anorexia nervosa will die from the disorder. The prevalence of eating disorders has been increasing since the 1950s. These disorders typically begin in adolescence, with onset by age 20 in over 85% of patients. Among females, the lifetime prevalence of anorexia nervosa is approximately 0.5% to 1.0% and the lifetime prevalence of bulimia nervosa is approximately 2%. When anorexia nervosa occurs in younger children, it may be part of more severe psychopathology. Individuals who are afflicted at a young age, however, tend to have a better prognosis in terms of remission
of the disorder. Bulimia nervosa has a slightly older profile, affecting 1% to 3% of girls during adolescence and up to 4% in young adulthood. Both anorexia nervosa and bulimia nervosa are eight to ten times more prevalent in females than in males depending on age and type of eating disorder. There is also a strong cultural component. Both disorders are more common in Western postindustrialized nations including the United States. Caucasians are more often affected than African Americans or Hispanic Americans, although the latter two groups show higher rates for obesity and binge eating. Immigrants to Western countries tend to be afflicted at a rate similar to their new society.
of the disorder. Bulimia nervosa has a slightly older profile, affecting 1% to 3% of girls during adolescence and up to 4% in young adulthood. Both anorexia nervosa and bulimia nervosa are eight to ten times more prevalent in females than in males depending on age and type of eating disorder. There is also a strong cultural component. Both disorders are more common in Western postindustrialized nations including the United States. Caucasians are more often affected than African Americans or Hispanic Americans, although the latter two groups show higher rates for obesity and binge eating. Immigrants to Western countries tend to be afflicted at a rate similar to their new society.
Differential Diagnosis and Comorbid Conditions
Ruling out medical illness is important to the diagnostic process, as anorexia and weight loss can be a presenting symptom of many medical illnesses, including: neoplasms and the associated paraneoplastic syndrome, acquired immunodeficiency syndrome (AIDS) and other infectious diseases, vascular disease (e.g., the superior mesenteric artery syndrome), metabolic abnormalities, and endocrine disease.
Other psychiatric disorders should also be evaluated both as etiologies for weight loss and as relevant comorbidities. The loss of appetite or weight occurs in major depressive disorder (MDD). The depressed individual without an eating disorder, however, will not want to lose weight and will often complain of the loss of appetite. The weight loss, therefore, should abate with successful treatment of the MDD. Treatment of MDD comorbid with anorexia nervosa may make the patient more amenable to treatment; up to 60% of those with anorexia can present with premorbid or comorbid MDD.
Changes and idiosyncrasies in eating behavior can occur in schizophrenia, however, these individuals rarely have the distorted body image demonstrated in anorexia nervosa. Obsessive compulsive disorder (OCD), body dysmorphic disorder, and social phobia share features with anorexia nervosa regarding repetitive behaviors, need for perfection, or social avoidance, but they do not usually involve weight loss. Anxiety disorders are also highly comorbid, particularly OCD which may occur in 30% of those with anorexia. A diagnosis of OCD should be made only if the compulsive behaviors extend beyond those related to food and eating.
In adults, both anorexia nervosa and bulimia nervosa show an association with personality disorders. Features of avoidant personality disorder are especially common in individuals with anorexia while features of borderline personality disorder including impulsivity and substanceuse disorders are more common in individuals with bulimia and those with the subtype of binging and purging in anorexia.
Etiology and Pathogenesis
There is no known etiology for either anorexia nervosa or bulimia nervosa. A combination of biologic, psychological, environmental, and social factors have been implicated in their pathogenesis. Once a pattern of disordered eating begins, multidetermined factors maintain and promote the dysregulated eating patterns.
While no candidate gene has been identified for either disorder, data from family and twin studies suggest heritable factors. Anorexia nervosa has a concordance rate of nearly 70% for identical twins and 20% for nonidentical twins. Bulimia nervosa also shows a higher concordance in monozygotic twins than dizygotic twins. First-degree relatives of those with anorexia are more likely to develop anorexia. There is also an increased prevalence of mood disorders among the first-degree relatives, particularly among the binge-purging type. Bulimia shares this same heritability profile, but has the additional vulnerability of higher rates of substance-use
disorders and substance-dependence disorders in first-degree relatives. Males in particular are at higher risk if there is genetic loading in first-degree relatives.
disorders and substance-dependence disorders in first-degree relatives. Males in particular are at higher risk if there is genetic loading in first-degree relatives.
While heritable factors are important, psychological and sociocultural factors are also important to understand in the development of eating disorders. A diathesis-stress model is helpful in understanding the interplay between genetic predisposition and vulnerability to psycho-socio-cultural influences and stressors. The large national and cultural differences in these disorders support an important role of societal preferences. Specifically, it has been hypothesized that the high rates of eating disorders in young women and men pursuing professional acting, modeling, and dancing careers and those youth who emulate media stars is secondary to the emphasis on an excessively lean appearance as a standard of attractiveness. Similarly, in athletic activities requiring a low weight, such as gymnastics and wrestling, there is also an increased occurrence of abnormal eating behaviors. Weight loss or decreased appetite as a result of illness or self-directed dieting are common gateways into eating disorders. Initial results may lead to weight loss which is almost uniformly seen and commented on positively by others lending itself to a boost in self-esteem and excessive attention to appearance. This then can lead to further restricting, exercising, bingeing, and eventually semistarvation. Because semistarvation itself can lead to many of the same cognitions and behaviors common in individuals with anorexia, it is not unusual for semistarvation to take on a life of its own that then evolves into a more classic eating disorder. Semistarvation can also mimic many of the symptoms associated with depression and anxiety or can lower the individual’s resilience to warding off normal occurrences or reactions of depression or anxiety resulting in an escalation of these normal occurrences for frequency and intensity. Additionally while there is no uniform personality type for the development of an eating disorder, it is not uncommon for those with anorexia to be attractive, intelligent, possessing a preference for predictability, tendencies toward perfectionism, acutely sensitive to others, and often described as caregivers.
Clinical Course
Anorexia Nervosa
The vast majority of new cases of anorexia nervosa typically onset in mid-to-late adolescence (age 14 to 18 years) to early adulthood (approximately 25 years old) with later onset being rarer thereafter but still occurring. Its onset is often associated with a stressful life event (e.g., significant illness, school or work transitions, change in peer group, change in family configuration, trauma) or an individual’s high dissatisfaction with his/her body as compared to social standards of the “perfect body.” The course and outcome of anorexia nervosa can be highly variable. Some individuals recover fully after a single episode, some exhibit a fluctuating pattern of weight gain followed by relapse with eventual recovery, and others experience a chronically deteriorating course over many years. Particularly within the first 5 years of onset, up to 50% of individuals with the restricting type of anorexia nervosa develop binge eating, indicating a change to the binge eating/purging subtype. A sustained shift in clinical presentation to weight gain plus binge eating and purging may eventually warrant a change in diagnosis to bulimia nervosa. Of the remainder who do not show such a shift in presentation, many have a chronic course with high likelihood of depression and anxiety. Mortality is relatively high compared to other psychiatric disorders with estimate that approximately 6% of those with anorexia die a premature death from complications of malnutrition, bradycardia, and electrolyte abnormalities, and another 5% or higher die from suicide.
Bulimia Nervosa
Bulimia nervosa usually onsets in late adolescence. The first binge-eating episode is often preceded by dieting to address poor body image and as an attempt to lose weight. Dieting creates excessive hunger and cravings which then lead to the binge resulting in guilt or feelings of failure.
This in turn fuels further poor body image and low self-esteem which lead to purging or other compensatory behaviors to “undo” the binge and restore a sense of relief and control. This cycle repeats itself over and over again, often becoming a habitual way of living. Typically, the course is chronic, although there may be interspersed periods of remission. As the individual passes from early into middle adulthood, symptoms tend to decrease. Periods of remission longer than 1 year are associated with better long-term outcome. Mortality is rare and is usually related to underlying pathology that was exacerbated by the rigors of frequent purging.
This in turn fuels further poor body image and low self-esteem which lead to purging or other compensatory behaviors to “undo” the binge and restore a sense of relief and control. This cycle repeats itself over and over again, often becoming a habitual way of living. Typically, the course is chronic, although there may be interspersed periods of remission. As the individual passes from early into middle adulthood, symptoms tend to decrease. Periods of remission longer than 1 year are associated with better long-term outcome. Mortality is rare and is usually related to underlying pathology that was exacerbated by the rigors of frequent purging.
Assessment
The essentials of assessment for eating disorders are summarized in Table 13-2. The diagnosis of anorexia nervosa and bulimia nervosa is based on the history, physical examination, psychiatric interview, and mental-status examination. Standardized assessment instruments are also helpful adjuncts to the evaluation.
Medical
The physical examination provides the first clues regarding the patient’s compromised health. A flow chart should be started to determine the youth’s actual growth history compared to the current and expected height and weight for age. Measures taken for the physical exam should include height, weight, orthostatic blood pressure, and heart rate and body temperature to assess for concerns of low body mass index (BMI), cardiac functioning, and hypothermia. Laboratory assessment includes: blood urea, potassium, sodium, chloride, bicarbonate, calcium, magnesium, phosphate, creatinine, full blood picture, erythrocyte sedimentation rate, electrocardiogram, urinalysis, urine pregnancy test, and dual-energy x-radiograph absorptiometry (DEXA) scan of
the spine or hip. Bone density is often lost in the malnourished state and restoration of weight and normalized eating can help to address the loss.
the spine or hip. Bone density is often lost in the malnourished state and restoration of weight and normalized eating can help to address the loss.
TABLE 13-2 Essentials of Assessment of Eating Disorders | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
History and Physical Examination
Anorexia Nervosa
Because of the special circumstances presented when assessing youth for eating disorders (e.g., their tendency to under-report their eating-disordered behaviors and symptoms, over-report their intake, and/or deny any concerns), parents can be a particularly valuable resource. Questions to ask parents include: What concerns do you have about your child’s eating, weight, growth? How much do you actually see your son/daughter eat? Is he/she on a particularly restrictive diet (e.g., vegan, vegetarian, low-fat, no “junk” food) and willing to find nutritious and diverse options within these parameters? Does s/he appear to spend long times in the bathroom immediately after meals (purging)? Do food items (e.g., tubs of ice cream) disappear without explanation (binge eating)? Does your child exercise an inordinate amount on a very regular basis? Does s/he make excessive remarks about his/her body weight and shape or ask for frequent assurance regarding body weight and shape or appearance. Affirmative answers to any of these questions should guide further clinical exploration.
The medical management of the adolescent with an eating disorder requires knowledge of the physical presentations and quick attention to the medical complications that may occur. Significant weight loss by unhealthy methods establishes the first criteria for anorexia nervosa. This information is needed to make decisions about medical and nutritional management. Physical complaints and findings on examination are consistent with those of acute malnutrition. While the vast majority of these individuals will likely appear cachectic, there is a subset of teens with anorexia who, despite significant weight loss from unhealthy anorexic practices, present within the average weight range due to being previously obese. Thus, for the assessment of anorexia, what is most important is the amount and rapidity of the weight loss and methods used to achieve weight loss and not sole reliance on a cachectic appearance. Adolescents engaging in anorexic behaviors may complain of decreased cold tolerance, dysregulation in sleep/wake cycle, low energy, weakness, feeling of fullness after minimal intake, bloating, constipation, primary or secondary amenorrhea, delayed puberty, and acrocyanosis. There may be hypotension, chest pain, and/or bradycardia with associated vertigo and syncope. In terms of dermatologic findings, individuals with anorexia nervosa often exhibit hair loss, dry skin, sometimes with lanugo (fine hair) on their arms, thighs, face, or trunks and rarely a yellowing of the skin associated with hypercarotenemia. Head and neck examination may exhibit hypertrophy of the parotid glands and erosion of the dental enamel in those inducing emesis. A comprehensive evaluation of anorexia nervosa includes the consideration of medical conditions that may cause weight loss. These may include metabolic, infectious, neoplastic, and endocrine illnesses. Physiologic monitoring includes a complete blood count (CBC), electrolytes, glucose, liver function tests, and thyroid function tests. While anorexia nervosa is typically accompanied by a normal laboratory profile, some findings may be abnormal due to malnutrition (e.g., nutritional anemia) and dehydration. Typical abnormalities are included in Table 13-3.
Electrocardiographic (EKG) studies usually show sinus bradycardia and, arrhythmias are rarely observed which can be particularly malignant in the presence of hypo or hyperkalemia and this is a primary reason why medical hospitalization occurs. These laboratory values generally remain normal until the late stages of illness. Therefore, these values should not independently influence decisions about the intensity of treatment.
Finally, bone loss is common due to starvation, placing anorectic youth at risk for osteoporosis. This risk persists even after normal weight has been restored. Nonconventional approaches to increase bone density include, oral contraceptives and dihydroepiandosterone (DHEA).
Both remain poorly researched and may mask the body’s own ability to resume menses which is an important marker for assessing recovery and promoting bone density without the use of outside agents.
Both remain poorly researched and may mask the body’s own ability to resume menses which is an important marker for assessing recovery and promoting bone density without the use of outside agents.
Related posts:
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
