Overview

Since the inclusion of binge eating disorder (BED) as a diagnosis in the fifth edition of Diagnostic and Statistical Manual of Mental Disorders (DSM-5) in 2013,¹ and the approval of lisdexamfetamine to treat moderate to severe BED in 2015,Reference Citrome^{2 ,} Reference Ward and Citrome³ interest in the disorder has continued at a rapid pace. A bibliometric search of the US National Library of Medicine’s PubMed.gov resource using the text word query “binge eating disorder” revealed 2732 publications, of which 848 have appeared since the publication of the previous version of this review in December 2015.Reference Citrome⁴

New information is available on the epidemiology of BED in the USA and provides somewhat lower prevalence estimates than prior reports,Reference Hudson, Hiripi and Pope^{5 ,} Reference Kessler, Berglund and Chiu⁶ but the data continue to follow the same patterns when comparing the prevalence and course of BED with other eating disorders. This new analysis is from a nationally representative sample of US adults using data from the 2012–2013 National Epidemiologic Survey on Alcohol and Related Conditions (NESARC-III) comprising of over 36,000 respondents assessed with lay-administered diagnostic interviews.Reference Udo and Grilo⁷ Lifetime and 12-month prevalence of DSM-5-defined BED were 0.85% and 0.44%, respectively. Compared to other eating disorders, these rates are substantially higher than the estimate for lifetime and 12-month prevalence rates for anorexia nervosa (0.80% and 0.05%) or bulimia nervosa (0.28% and 0.14%). Women are more likely than men to be diagnosed with BED, with lifetime prevalence rates of 1.25% for women and 0.42% for men. Lifetime BED prevalence rates were 0.94% for non-Hispanic whites, 0.62% for non-Hispanic blacks, 0.75% for Hispanics, and 0.59% for “other” race/ethnicity. Compared with lifetime anorexia nervosa or bulimia nervosa, those with lifetime BED had a later age of onset of their eating disorder and a longer duration of their episodes. Although about 56% of people with lifetime BED in the NESARC-III analysis were obese (body mass index (BMI) ≥ 30 kg/m²), 20% were normal weight (BMI 18.5–24.9 kg/m²) and 23% overweight (25–29.9 kg/m²).

BED is associated with distress and problems in functioning. Consequences of BED include problems adapting to social roles, poor quality of life and less life satisfaction due to health issues, increased overall medical morbidity and mortality related to weight gain and obesity, and increased use of health-care resources.¹ In one survey, impaired role functioning in work/school, social, and family life, as measured by the Sheehan Disability Scale, was observed in 63% of adults with BED, with 18.5% of adults with BED reporting severe functional impairment.Reference Hudson, Hiripi and Pope⁵ In the analysis of the NESARC-III data,Reference Udo and Grilo⁷ for lifetime diagnoses, rates of any impairment in social function were significantly greater for bulimia nervosa (61.4%) and BED (53.7%) than for anorexia nervosa (30.7%). Moreover, rates of reporting of interference with normal daily activities were significantly greater for BED (52.5%) and bulimia nervosa (49.5%) than for anorexia nervosa (23.5%).

Psychiatric comorbidities are very common, with one study noting that 79% of adults with BED also experience anxiety disorders (65%), mood disorders (46%), impulse control disorders (43%), or substance use disorders (23%).Reference Hudson, Hiripi and Pope⁵ Multiple psychiatric comorbidities are also common and almost 50% of persons with BED have ≥ 3 psychiatric comorbidities.Reference Hudson, Hiripi and Pope⁵ The psychiatric comorbidity is linked to the severity of binge eating and not to the degree of obesity.¹ In an additional analysis of the NESARC-III data,Reference Udo and Grilo⁸ the percentage reported for meeting criteria for a comorbid psychiatric disorder was even higher, at 94%, with BED significantly associated with any mood disorder, major depressive disorder, persistent depression, any anxiety disorder, all individual anxiety disorders (except for panic disorder), posttraumatic stress disorder, alcohol use disorder, any personality or conduct disorder, and all individual personality and conduct disorders. Moreover, after adjusting for sociodemographic variables, BED was significantly associated with increased odds of diabetes, hypertension, high cholesterol, high triglycerides, minor heart conditions, stomach ulcer, arthritis, sleep problems, anemia, fibromyalgia, bowel problems, osteoporosis, lung problems, liver diseases, and nerve problems. After additionally adjusting for other psychiatric disorders, odds ratios for diabetes, hypertension, high cholesterol, and high triglycerides remained significant.

It must be emphasized that BED is distinct from obesity; most obese individuals do not engage in recurrent binge eating. Moreover, compared with weight-matched obese individuals without BED, those with BED consume more calories in laboratory studies and have greater functional impairment, lower quality of life, more subjective distress, and greater psychiatric comorbidity.¹ In general, individuals with BED report being insufficiently physically active, more so than people who are overweight/obese or healthy weight individuals.Reference Carr, Lydecker and White⁹

Psychological treatments including cognitive behavioral therapy (CBT) and interpersonal therapy (IPT) have been recommended as first lineReference Wilson^{10 ,} Reference Grilo¹¹ and are supported by several different meta-analytic reviews.Reference Vocks, Tuschen-Caffier and Pietrowsky^{12 –}Reference Brownley, Berkman and Peat¹⁸ Although CBT and IPT can reduce binge eating behavior, access to such treatments may be limited because of local availability and/or cost. Moreover, 33–50% of patients with BED do not appear to benefit completely or sufficiently from psychological and behavioral treatment.Reference Linardon¹⁵ Also, psychological interventions for BED have evidenced little to no weight loss, although successfully eliminating binge eating can protect against future weight gain. Routine medication treatments for anxiety and depression do not necessarily ameliorate the symptoms of BED, but there are approved and emerging medication options, lisdexamfetamine and dasotraline, respectively, that specifically address the core drivers behind binge eating, namely obsessive thoughts and compulsive behaviors regarding food, resulting in marked decreases in binge eating behaviors as well as weight loss.Reference Ward and Citrome³

Review of the DSM-5 diagnostic criteria for BED

In the DSM-5, BED is defined by recurrent episodes of binge eating (eating in a discrete period of time an amount of food larger than most people would eat in a similar amount of time under similar circumstances and a sense of lack of control over eating during the episode), occurring on average at least once a week for 3 months, and associated with marked distress.¹ Binge episodes are also associated with ≥ 3 of the following: eating rapidly, eating until feeling uncomfortably full, eating large amounts of food when not feeling physically hungry, eating alone because of feeling embarrassed by how much one is eating, and feeling disgusted with oneself, depressed, or guilty afterwards. It is not unusual for all these associated features to be present. Although overvaluation of shape or weight is often seen (40%), it is presently not part of the DSM-5 criteria for BED.Reference Grilo, Crosby and Masheb^{19 –}Reference Wilfley, Citrome and Herman²¹ BED is distinguished from bulimia nervosa, in that BED is not associated with regular compensatory behaviors such as purging or excessive exercise, or with dietary restriction, although frequent dieting may be reported.

Since binge eating is often a secretive behavior, and commonly associated with a high degree of embarrassment or shame, Reference Herman, Safikhani and Hengerer^{22 ,} Reference Lydecker and Grilo²³ it is not ordinarily revealed unless the clinician makes a direct inquiry regarding eating patterns. A screening instrument, based on the DSM-5 criteria, is available.Reference Herman, Deal and DiBenedetti^{24 ,} Reference Herman, Deal and Kando²⁵

Although physical comorbidities including obesity and metabolic syndrome are common, and may prompt a discussion of eating behaviors, not all persons with BED are obese. Because BED is commonly associated with other psychiatric disorders that bring them to treatment, such as anxiety, depression, impulse control disorders, and substance use, routine assessment of eating behaviors is advisable because persons with prominent coexisting psychiatric conditions, and as yet undiagnosed BED, may not bring up eating issues on their own.Reference Citrome²⁶

DSM-5 also provides for the specification of partial remission where after full criteria for BED were previously met, binge eating occurs at an average frequency of less than one episode per week for a sustained period of time. For full remission, after full criteria for BED were previously met, none of the criteria have been met for a sustained period of time.

Current severity can also be specified. The minimum level of severity is based on the number of weekly binge eating episodes (mild, 1–3; moderate, 4–7; severe, 8–13; extreme, ≥ 14); however, severity level can be increased to reflect other symptoms and functional disability. For example, someone binging two or three times a week and experiencing substantial distress could be assigned a severity level of moderate instead of mild.

The text in DSM-5 provides additional guidance that is helpful when assessing eating behaviors.¹ Context is important, for example, a quantity of food that might be regarded as excessive for a typical meal might be considered normal during a celebration or holiday meal, such as Thanksgiving. The “discrete period of time” refers to a limited period, usually less than 2 h but a single episode of binge eating need not be restricted to one setting. The text in DSM-5 gives the example of an individual starting a binge in a restaurant and then this continues upon returning home. However, when evaluating a patient for BED, continual snacking on small amounts of food throughout the day would not be considered an eating binge. The food consumption must be accompanied by a sense of lack of control to be considered an episode of binge eating. This means that the person with BED is unable to refrain from eating or to stop eating once started. It is not unusual for an individual to continue binge eating if the phone rings; however, if a roommate or spouse unexpectedly enters the room, the behavior may immediately cease, and can be followed by significant embarrassment. Patients may also describe the eating as a dissociative experience. Some patients with BED may be unable to clearly articulate an acute feeling of loss of control but instead describe a generalized pattern of uncontrolled eating. The text in DSM-5 adds that if individuals report that they have abandoned efforts to control their eating, loss of control may still be considered as present.

In addition to spontaneous episodes of binge eating when opportunities present themselves, binge eating can also be planned in some instances by the hoarding of foods in secret places. The actual types of foods consumed are not necessarily sugary or salty snacks, or carbohydrates, but can also include fruit, yogurt, or foods ordinarily considered as “healthy.” The types of food consumed during binge eating episodes vary both across individuals and for a given individual, and the binge eating episode is characterized more by an abnormality in the amount of food consumed than by a craving for a specific food.

BED prior to DSM-5

BED is not a new entity. Walter Hamburger in 1951 described “a compulsive craving for food… This craving is frequently uncontrollable and must be satisfied.”Reference Hamburger²⁷ Albert Stunkard in 1959 described “enormous amounts of food may be consumed in relatively short periods… is regularly followed by severe discomfort and self-condemnation.”Reference Stunkard²⁸ In 1980, binge behavior was included as a component of the DSM-III diagnostic criteria for bulimia.²⁹ Research on binge eating in the 1980s was commonly focused on obese persons, and in general, the observed differences between obese binge and obese non-binge eaters included greater levels of psychopathology among the binge-eaters, as well as a greater likelihood to drop out of weight-loss treatment and being more likely to regain lost weight more rapidly.Reference Yanovski³⁰ The concept of “purging” and “non-purging” bulimia was further refined, with persons with either disorder exhibiting lower self-esteem and higher anxiety than non-bulimic controls.Reference Grace, Jacobson and Fullager³¹ In 1987, the diagnostic entity of “Bulimia” in DSM-III was replaced by “Bulimia Nervosa” in DSM-III-R, ³² and criteria were made more specific, requiring both binge eating and compensatory behaviors, with a minimum average of two binge eating episodes a week for at least 3 months, and with persistent overconcern with body shape and weight. Consequently, binge eaters without compensatory behaviors could no longer be diagnosed using DSM-III-R. The diagnostic entity of BED was offered as a solution to this problem,Reference Spitzer, Devlin and Walsh^{33 –}Reference Spitzer, Yanovski and Wadden³⁵ but ultimately BED was not adopted for the DSM-IV when released in 1994,³⁶ and the use of the diagnostic entity “Eating Disorder Not Otherwise Specified” (EDNOS) was the option provided to diagnose BED patients. Although specific research criteria for BED were outlined in Appendix B (Criteria Sets and Axes Provided for Further Study) of the DSM-IV, these were not intended for clinical use outside research settings. This situation remained unchanged in 2000 with the release of DSM-IV-TR.³⁷ In clinical settings, EDNOS was frequently diagnosed and became the most commonly documented eating disorder diagnosis.Reference Fairburn and Bohn³⁸ Overreliance on “Not Otherwise Specified” or miscellaneous categories is not desirable in any diagnostic schema, and ultimately BED was recognized as a distinct eating disorder upon the publication of DSM-5 in 2013.¹

Neurobiology

Essential to the understanding of BED is that there is a loss of control over eating. This is related to obsessive thoughts about food and associated compulsive eating behaviors. When BED is successfully treated, decreases in binge eating frequency are highly correlated with reductions in scores on scales that measure food-related obsessive thoughts and compulsive behaviors.Reference Citrome, Kando and Bliss³⁹ Multiple neurobiological explanations have been suggested for BED, including dysregulation in reward center and impulse control circuitry,Reference Schienle, Schäfer and Hermann^{40 –}Reference Schäfer, Vaitl and Schienle⁴² with potentially related disturbances in dopamine neurotransmission that regulates “wanting food”Reference Davis, Levitan and Yilmaz^{43 –}Reference Heal, Hallam and Prow⁴⁵ and endogenous μ-opioid signaling that regulates “liking food”.Reference Heal, Hallam and Prow^{45 –}Reference Davis, Levitan and Reid⁴⁷

Additionally, there is likely an interplay between genetic influences such as functional polymorphisms of the dopamine D2 receptor gene and of the μ-opioid geneReference Davis, Levitan and Reid^{47 –}Reference Trace, Baker and Peñas-Lledó⁴⁹ and environmental stressors.Reference Pike, Wilfley and Hilbert^{50 ,} Reference Halmi⁵¹ Antecedents to binge eating include negative affect; interpersonal stressors; dietary restraint; negative feelings related to body weight, body shape, and food; and boredom.¹

Recognizing and Diagnosing Binge Eating Disorder

BED can be invisible. Feelings of shame and embarrassment about eating behaviors are very common among persons with BED and thus symptom concealment is often encountered, with families usually unaware of the extent of the binge eating behaviors. Persons with BED may not know that BED is an actual disorder and that there are treatments for it, and thus it may not be spontaneously brought up for discussion. Typically, it is commonly a person’s psychiatric and somatic comorbidities that are the focus of the health-care provider’s attention, and the BED consequently goes unrecognized. In an Internet survey conducted in 22,397 US adults, 344 participants (1.5%) met the DSM-5 criteria for BED in the past 12 months, but of these 344 respondents with BED, only 11 (3.2%) had ever been diagnosed with BED by a health-care provider.Reference Cossrow, Pawaskar and Witt⁵²

As noted, a screening instrument is available.Reference Herman, Deal and DiBenedetti^{24 ,} Reference Herman, Deal and Kando²⁵ Called the Binge Eating Disorder Screener-7 (BEDS-7), it was developed based in part on the DSM-5 diagnostic criteria and is intended to be completed by the patient. The first question is “During the last 3 months, did you have any episodes of excessive overeating (i.e., eating significantly more than what most people would eat in a similar period of time)?” If the answer is no, the remaining six questions do not apply. Otherwise, the reminder of the screener is completed, and depending on the answers provided, a more thorough clinical evaluation based upon the complete DSM-5 criteria for BED should be done. A simpler approach would be to ask patients routinely about loss of control over eating.Reference Citrome⁵³ Clinicians already routinely ask about appetite and change in weight when conducting health examinations. It is not unduly burdensome to then ask, “Have you ever eaten more than you intended?” followed by “Did you ever feel like it wasn’t easy to stop?” If these questions are endorsed, a more complete evaluation will be required.

The DSM-5 criteria for BED, when discussed with the patient, can be a powerful psychoeducational tool that can help patients feel validated that their symptoms are real and that they have a well-defined disorder. However, attention will need to be paid to the words used to ask about eating as evidenced in a study where language preferences for discussing obesity and binge eating were examined in over 800 people in an online community sample.Reference Lydecker, Galbraith and Ivezaj^{54 ,} Reference Citrome⁵⁵ The preferred obesity‐related terms were “weight” and “BMI.” Binge‐related terms were generally ranked neutrally, and preferred descriptions were “kept eating even though not physically hungry” and “loss of control.” Specific words to avoid include “fatness” and “excess fat,” as well as “large size,” “heaviness,” and “obesity.” Also to be avoided are terms such as “willpower.” It was noted that discussions about weight and binge eating are very sensitive and that “conversations about weight and binge eating might create such distress that individuals would prefer not to discuss the topics at all.”Reference Lydecker, Galbraith and Ivezaj⁵⁴ Gender differences included women’s stronger aversions to some terms, possibly related to more frequent experiences of weight stigmatization than men or to greater sensitivity to potentially pejorative terms. The authors concluded that “healthcare providers are encouraged to practice sensitivity and display empathy during discussions of weight and weight loss counseling with female patients in particular.”Reference Lydecker, Galbraith and Ivezaj⁵⁴ Additional obstacles to a comprehensive evaluation, as identified in a study of physician–patient conversations about BED,Reference Kornstein, Keck and Herman⁵⁶ included the observations that psychiatrists focused on weight‐related issues, whereas patients focused on the emotional impact and triggers of binge eating episodes, and that there is often miscommunication about the severity of binge eating episodes, as well as judgment, bias, and shame surrounding BED.

The text in DSM-5 provides useful information on differential diagnosis.¹ When contrasting BED with bulimia nervosa, the recurrent inappropriate compensatory behavior (e.g., purging, excessive exercise, diuretic abuse, laxative abuse) seen in bulimia nervosa is absent in BED, and although persons with BED may report frequent attempts at dieting, they do not display marked or sustained dietary restriction. When contrasting BED with simple obesity, the levels of overvaluation of body weight and shape, and rates of psychiatric comorbidity are higher in obese individuals with BED than in those without BED. Regarding BED and mood disorders, increases in appetite and weight gain are included in the criteria for major depressive episode and in the atypical features specifiers for depressive and bipolar disorders, however, increased eating in the context of a mood episode may or may not be associated with loss of control; if the full criteria for both disorders are met, both diagnoses can be given. When considering BED and borderline personality disorder, binge eating is included in the impulsive behavior criterion that is part of the definition of borderline personality disorder; if the full criteria for both disorders are met, both diagnoses should be given.

Treatments for Binge Eating Disorder

There is an App for that

Smartphone applications (apps) have become popular. However, evidence supporting many of the health apps is lacking and care must be taken when recommending them to patients.Reference Citrome⁸¹ Many eating disorder apps are geared toward making it simpler to log binge eating but can also help provide meal reminders, affirmations, and seamless patient–clinician in-app linkage. “Recovery Record” is perhaps one of the better-known eating disorder smartphone apps and is described in the literature by its authorsReference Tregarthen, Lock and Darcy^{82 ,} Reference Kim, Sadeh-Sharvit and Darcy⁸³ and users.Reference Lindgreen, Lomborg and Clausen⁸⁴ Another “Noom Monitor” is intended to facilitate guided self-help CBT.Reference Hildebrandt, Michaelides and Mackinnon⁸⁵ Reviews of smartphone apps for the treatment of eating disorders are available and should be studied before proceeding with their use.Reference Juarascio, Manasse and Goldstein^{86 ,} Reference Fairburn and Rothwell⁸⁷

Disclosures

Dr. Citrome reports personal fees for consulting from Acadia, Alkermes, Allergan, Impel, Indivior, Intra-Cellular Therapeutics, Janssen, Lundbeck, Merck, Neurocrine, Noven, Osmotica, Otsuka, Pfizer, Shire, Sunovion, Takeda, Teva, Vanda; personal fees for speaker bureau activities from Acadia, Alkermes, Allergan, Janssen, Lundbeck, Merck, Neurocrine, Otsuka, Pfizer, Shire, Sunovion, Takeda, Teva; and royalties from Wiley, UpToDate, Springer Healthcare, outside the submitted work.