41 Etiology and Treatment of Eating Disorders

Module Outline

• Etiology
• Treatment

Module Learning Outcomes

• Describe the etiology of feeding and eating disorders.
• Describe treatment options for feeding and eating disorders.

Etiology

Section Learning Objectives

• Describe the biological causes of feeding and eating disorders.
• Describe the cognitive causes of feeding and eating disorders.
• Describe the sociocultural causes of feeding and eating disorders.
• Describe how personality traits are the cause of feeding and eating disorders.

What causes eating disorders? While researchers have yet to identify a specific cause of eating disorders, the most compelling argument to date is that eating disorders are multidimensional disorders. This means many contributing factors lead to the development of an eating disorder. While there is likely a genetic predisposition, there are also environmental, or external factors, such as family dynamics and cultural influences that impact their presentation. Research supporting these influences is well documented for anorexia nervosa and bulimia nervosa; however, seeing as BED has only just recently been established as a formal diagnosis, research on the evolvement of BED is ongoing.

Biological

There is some evidence of a genetic predisposition for eating disorders, with relatives of those diagnosed with an eating disorder being up to six times more likely than other individuals to be diagnosed also. Twin concordance studies also support the gene theory. If an identical twin is diagnosed with anorexia, there is a 70% percent chance the other twin will develop anorexia in their lifetime. The concordance rate for fraternal twins (who share less genes) is 20%. While not as strong for bulimia, identical twins still display a 23% concordance rate, compared to the 9% rate for fraternal twins.

In addition to hereditary causes, disruption in the neuroendocrine system is common in those with eating disorders (Culbert, Racine, & Klump, 2015). Unfortunately, it’s difficult for researchers to determine if these disruptions caused the disorder or have been caused by the disorder, as manipulation of eating patterns is known to trigger changes in hormone production. With that said, researchers have explored the hypothalamus as a potential contributing factor. The hypothalamus is responsible for regulating body functions, particularly hunger and thirst (Fetissov & Mequid, 2010). Within the hypothalamus, the lateral hypothalamus is responsible for initiating hunger cues that cause the organism to eat, whereas the ventromedial hypothalamus is responsible for sending signals of satiation, telling the organism to stop eating. Clearly, a disruption in either of these structures could explain why an individual may not take in enough calories or experience periods of overeating.

Psychological Factors

Cognitive. Some argue that eating disorders are, in fact, a variant of obsessive-compulsive disorder  (OCD). The obsession with body shape and weight—the hallmark of an eating disorder—is likely a driving factor in anorexia nervosa. Distorted thought patterns and an over-evaluation of body size likely contribute to this obsession and one’s desire for thinness. Research has identified high levels of impulsivity, particularly in those with binge eating episodes, suggesting a temporary lack of control is responsible for these episodes. Post binge-eating episode, many individuals report feelings of disgust or even thoughts of failure. These strong cognitive factors are indicative as to why cognitive-behavioral therapy is the preferred treatment for eating disorders.

     Perfectionism. It should come as no surprise that perfectionism, or the belief that one must be perfect, is a contributing factor to disorders related to eating, weight, and body shape (particularly anorexia nervosa). While an exact mechanism is unknown, it is believed that perfectionism magnifies normal body imperfections, leading an individual to go to extreme (i.e., restrictive) behaviors to remedy the flaw (Hewitt, Flett & Ediger, 1995).

     Self-Esteem. Self-esteem, or one’s belief in their worth or ability, has routinely been identified as a moderator of many psychological disorders, and eating disorders are no exception. Low self-esteem not only contributes to the development of an eating disorder but is also likely involved in the maintenance of the disorder. One theory suggests that overall low self-esteem increases the risk for over-evaluation of body, which in turn, leads to negative eating behaviors that could lead to an eating disorder (Fairburn, Cooper & Shafran, 2003).

Sociocultural

Eating disorders are overwhelmingly found in Western countries where there is a heavy emphasis on thinness—a core feature of eating disorders. However, while eating disorders were once thought of as disorders of higher SES societies, recent research suggests that there are increasing rates of eating disorders among ethnic minorities in the US as well as across non-Westernized countries.

     Media. One commonly discussed contributor to eating disorders is the media. The idealization of thin models and actresses sends the message to young women (and adolescents) that to be popular and attractive, you must be thin. These images are not isolated to magazines, but are also seen in television shows, movies, commercials, and large advertisements on billboards and hanging in store windows. With the emergence of social media (e.g., Facebook, Snapchat, Instagram), exposure to media images and celebrities is even easier.  Couple this with the ability to alter images to make individuals even thinner, it is no wonder many young people become dissatisfied with their body (Polivy & Herman, 2004).

     Gender. Males account for only a small percentage of eating disorders. While it is unclear as to why there is such a discrepancy, it is likely somewhat related to cultural desires of women being “thin” and men being “muscular” or “strong.” Of men diagnosed with an eating disorder, the overwhelming percentage of them identified a job or sport as the primary reason for their eating behaviors (Strother, Lemberg, Stanford, & Turberville, 2012). Jockeys, distance runners, wrestlers, and bodybuilders are some of the professions identified as most restrictive regarding body weight.

There is some speculation that males are not diagnosed as frequently as women due to the stigma attached to eating disorders. Eating disorders have routinely (and incorrectly) been stereotyped as a “white, adolescent female” problem. Due to this bias, young men may not seek help for their eating disorder in efforts to prevent labeling (Raevuoni, Keski-Rahkonen & Hoek, 2014).

     Family. Family influences are one of the strongest external contributors to maintaining eating disorders. Often family members are praised for their slenderness. Think about the last time you saw a family member or close friend- how often have you said, “You look great!” or commented on their appearance in some way? The odds are likely high. While the intent of the family member is not to maintain maladaptive eating behaviors by praising the physical appearance of someone struggling with an eating disorder, they are indirectly perpetuating the disorder.

While family involvement can help maintain the disorder, it can also contribute to the development of an eating disorder. Families that emphasize thinness or place a large emphasis on physical appearance are more likely to have a child diagnosed with an eating disorder (Zerbe, 2008). In fact, mothers with eating disorders are more likely to have children who develop a feeding/eating disorder than mothers without eating disorders (Whelan & Cooper, 2000). Additional family characteristics that are common among patients receiving treatment for eating disorders are enmeshed, intrusive, critical, hostile, or overly concerned with parenting (Polivy & Herman, 2002). While there has been some correlation between these family dynamics and eating disorders, they are not evident in all families of people with eating disorders.

Treatment

Section Learning Objectives

• Describe treatment options for anorexia nervosa.
• Describe treatment options for bulimia nervosa.
• Describe treatment options for binge eating disorder.
• Discuss the outcome of treatment for feeding and eating disorders.

Anorexia Nervosa

The immediate goal for the treatment of anorexia nervosa is weight gain and recovery from malnourishment. This is often established via an intensive outpatient program, or if needed, through an inpatient hospitalization program where caloric intake can be managed and controlled. Both the inpatient and outpatient programs use a combination of therapies and support to help restore proper eating habits. Of the most common (and successful) treatments are Cognitive-Behavioral Therapy (CBT) and Family-Based Therapy (FBT).

     CBT. Because anorexia nervosa requires changes to both eating behaviors as well as thought patterns, CBT strategies have been very effective in producing lasting changes to those suffering from anorexia nervosa. Some of the behavioral strategies include recording eating behaviors—hunger pains, quality and quantity of food—and emotional behaviors—feelings related to the food. In addition to these behavioral strategies, it is also important to address the maladaptive thought patterns associated with their negative body image and desire to control their physical characteristics. Changing the fear related to gaining weight is essential in recovery.

     Family based therapy (FBT). FBT is also an effective treatment approach, often used as a component of individual CBT, especially for children and adolescents with the disorder. FBT has been shown to elicit 50-60% of weight restoration in one year, as well as weight maintenance 2-4 years post-treatment (Campbell & Peebles, 2014; LeGrange, Lock, Accurso, Agras, Darcy, Forsberg, et al, 2014). Additionally, FBT has been shown to improve rapid weight gain, produce fewer hospitalizations, and is more cost-effective than other types of therapies with family involvement (Agras, Lock, Brandt, Bryson, Dodge, Halmi, et al., 2014).

FBT typically involves 16-18 sessions which are divided into 3 phases: (1) Parents take charge of weight restoration, (2) client’s gradual control of overeating, and (3) addressing developmental issues including fostering autonomy from parents (Chen, et al., 2016). While FBT has shown to be effective in treating adolescents with anorexia nervosa, the application for older eating patients (i.e., college-aged students and above) is still undetermined. As with adolescents, the goal for a family-based treatment program should center around helping the patient separate their feelings and needs from that of their family.

Bulimia Nervosa

Just as anorexia nervosa treatment initially focuses on weight gain, the first goal of bulimia nervosa treatment is to eliminate binge eating episodes and compensatory behaviors. The aim is to replace both negative behaviors with positive eating habits. One of the most effective ways to establish this is through Cognitive Behavioral Therapy (CBT).

     CBT. Similar to anorexia nervosa, individuals with bulimia nervosa are expected to keep a journal of their eating habits; however, with bulimia nervosa, it is also important that the journal include changes in sensations of hunger and fullness, as well as other feelings surrounding their eating patterns in efforts to identify triggers to their binging episodes (Agras, Fitzsimmons-Craft & Wilfley, 2017). Once these triggers are identified, psychologists will utilize specific behavioral or cognitive techniques to prevent the individual from engaging in binge episodes or compensatory behaviors.

One method for modifying behaviors is through Exposure and Response Prevention. As previously discussed in the OCD chapter, this treatment is very effective in helping individuals stop performing their compulsive behaviors by literally preventing them from engaging in the action, while simultaneously using relaxation strategies to reduce anxiety associated with not engaging in the negative behavior. Therefore, to prevent an individual from purging post-binge episodes, the individual would be encouraged to partake in an activity that directly competes with their ability to purge, e.g., write their thoughts and feelings in a journal at the kitchen table. Research has indicated that this treatment is particularly helpful for individuals suffering from comorbid anxiety disorders (particularly OCD; Agras, Fitzsimmons-Craft & Wilfley, 2017).

In addition to changing behaviors, it is also important to change the maladaptive thoughts toward food, eating, weight, and shape. Negative thoughts such as “I am fat” and “I can’t stop eating when I start” can be modified into more appropriate thoughts such as “My body is healthy” or “I can control my eating habits.”  By replacing these negative thoughts with more appropriate, positive thought patterns, individuals begin to control their feelings, which in return, can help them manage their behaviors.

     Interpersonal Psychotherapy (IPT). IPT has also been established as an effective treatment for those with bulimia nervosa, particularly if an individual has not been successful with CBT treatment. The goal of IPT is to improve interpersonal functioning in those with eating disorders. Originally a treatment for depression, IPT-E was adapted to address the social isolation and self-esteem problems that contribute to the maintenance of negative eating behaviors.

IPT-E has 3 phases typically covered in weekly sessions over 4-5 months. Phase One consists of engaging the patient in treatment and providing psychoeducation about their disease and the treatment program. This phase also includes identifying interpersonal problems that are maintaining the disease.

Phase Two is the main treatment component. In this phase, the primary focus is on problem-solving interpersonal issues. The most common types of interpersonal issues are lack of intimacy and interpersonal deficits, interpersonal role disputes, role transitions, grief, and life goals. Once the main interpersonal problem is identified, the clinician supports the patient in their pursuit to identify ways to change. A key component of IPT-E is the supportive role of the clinician, as opposed to the teaching role in other treatments. The idea is that by having the patient make changes, they can better understand their problems, and as a result, make more profound changes (Murphy, Straebler, Basden, Cooper, & Fairburn, 2012).

Phase Three is the final stage. The goals of this phase are to ensure that the changes made in Phase two are maintained. To achieve this, treatment sessions are spaced out, allowing patients more time to engage in their changed behavior. Additionally, relapse prevention (i.e., problem-solving ways not to relapse) is also discussed to ensure long term results. In doing this, the patient reviews the progress they have made throughout treatment, as well as identifying potential interpersonal issues that may arise, and how their treatment can be adapted to address those issues.

Support for IPT-E is limited; however, two extensive studies suggest that IPT-E is effective in treating bulimia nervosa, and possibly BED. While treatment is initially slower than CBT, it is equally effective in long-term follow-up and maintenance of disorder (Fairburn, Marcus, & Wilson, 1993).

Binge Eating Disorder

Given the similar presentations of BED and bulimia nervosa, it should not be surprising that the most effective treatments for BED are similar to that of bulimia nervosa. CBT, along with antidepressant medications, are among the most effective in treating BED. Interpersonal therapy, as well as dialectical behavioral therapy, have also been effective in reducing binge-eating episodes; however, they have not been effective in weight loss (Guerdjikova, Mori, Casuto, & McElroy, 2017). Goals of treatment are, of course, to eliminate binge eating episodes, as well as reduce body weight as most individuals with BED are overweight. Seeing as BED has only recently been established as a separate eating disorder, treatment research specific to this disorder is expected to grow.

     Antidepressant medications. Given the high comorbidity between eating disorders and depressive symptoms, antidepressants have been a primary method of treatment for years. While they have been shown to improve depressive symptoms, which may help individuals make gains in their eating disorder treatment, research has not supported antidepressants as an effective treatment strategy for treating the eating disorder itself.

Outcome of Treatment

Now that we have discussed treatments for eating disorders, how effective are they? Research has indicated favorable prognostic features for anorexia nervosa are early age of onset and a short history of the disorder. Conversely, unfavorable features are a long history of symptoms prior to treatment, severe weight loss, and binge eating and vomiting. The mortality rate over the first 10 years from presentation is about 10%. Most of these deaths are from medical complications due to the disorder or suicide.

Unfortunately, research has not identified any consistent predictors of positive outcomes for bulimia nervosa. However, there is some speculation that individuals with childhood obesity, low self-esteem, and those with a personality disorder have worse treatment outcomes. While treatment outcome for BED is still in its infancy, initial findings suggest that remission rates of BED are much higher than that for anorexia nervosa and bulimia nervosa.

Module Recap

This module covered eating disorders in terms of their clinical presentation, epidemiology, comorbidity, etiology, and treatment options.

3rd edition

“Etiology and Treatment of Eating Disorders” is adapted from Fundamentals of Psychological Disorders by Alexis Bridley and Lee W. Daffin Jr., used under Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.