Management of eating disorders.

Abstract

The RTI International-University of North Carolina at Chapel Hill Evidence-based Practice Center (RTI-UNC EPC) systematically reviewed evidence on efficacy of treatment for anorexia nervosa (AN), bulimia nervosa (BN), and binge eating disorder (BED), harms associated with treatments, factors associated with the treatment efficacy and with outcomes of these conditions, and whether treatment and outcomes for these conditions differ by sociodemographic characteristics.
We searched MEDLINE, the Cumulative Index to Nursing and Applied Health (CINAHL), PSYCHINFO, the Educational Resources Information Center (ERIC), the National Agricultural Library (AGRICOLA), and Cochrane Collaboration libraries.
We reviewed each study against a priori inclusion/exclusion criteria. For included articles, a primary reviewer abstracted data directly into evidence tables; a second senior reviewer confirmed accuracy. We included studies published from 1980 to September 2005, in all languages. Studies had to involve populations diagnosed primarily with AN, BN, or BED and report on eating, psychiatric or psychological, or biomarker outcomes.
We report on 30 treatment studies for AN, 47 for BN, 25 for BED, and 34 outcome studies for AN, 13 for BN, 7 addressing both AN and BN, and 3 for BED. The AN literature on medications was sparse and inconclusive. Some forms of family therapy are efficacious in treating adolescents. Cognitive behavioral therapy (CBT) may reduce relapse risk for adults after weight restoration. For BN, fluoxetine (60 mg/day) reduces core bulimic symptoms (binge eating and purging) and associated psychological features in the short term. Individual or group CBT decreases core behavioral symptoms and psychological features in both the short and long term. How best to treat individuals who do not respond to CBT or fluoxetine remains unknown. In BED, individual or group CBT reduces binge eating and improves abstinence rates for up to 4 months after treatment; however, CBT is not associated with weight loss. Medications may play a role in treating BED patients. Further research addressing how best to achieve both abstinence from binge eating and weight loss in overweight patients is needed. Higher levels of depression and compulsivity were associated with poorer outcomes in AN; higher mortality was associated with concurrent alcohol and substance use disorders. Only depression was consistently associated with poorer outcomes in BN; BN was not associated with an increased risk of death. Because of sparse data, we could reach no conclusions concerning BED outcomes. No or only weak evidence addresses treatment or outcomes difference for these disorders.
The literature regarding treatment efficacy and outcomes for AN, BN, and BED is of highly variable quality. In future studies, researchers must attend to issues of statistical power, research design, standardized outcome measures, and sophistication and appropriateness of statistical methodology.

Full text

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Evidence Report/Technology Assessment
Number 135


Management of Eating Disorders


Prepared for:
Agency for Healthcare Research and Quality
U.S. Department of Health and Human Services
540 Gaither Road
Rockville, MD 20850
www.ahrq.gov

Contract No. 290-02-0016

Prepared by:
RTI-UNC Evidence-Based Practice Center, Research Triangle Park, NC



Investigators
Nancy D. Berkman, Ph.D.
Cynthia M. Bulik, Ph.D.
Kimberly A. Brownley, Ph.D.
Kathleen N. Lohr, Ph.D.
Jan A. Sedway, Ph.D.
Adrienne Rooks, B.A.
Gerald Gartlehner, M.D.












AHRQ Publication No. 06-E010
April 2006

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This report is based on research conducted by the RTI International–University of North Carolina
at Chapel Hill (RTI-UNC) Evidence-based Practice Center (EPC) under contract to the Agency for
Healthcare Research and Quality (AHRQ), Rockville, MD (Contract No. 290-02-0016). The
findings and conclusions in this document are those of the author(s), who are responsible for its
content, and do not necessarily represent the views of AHRQ. No statement in this report should
be construed as an official position of AHRQ or of the U.S. Department of Health and Human
Services.

The information in this report is intended to help clinicians, employers, policymakers, and others
make informed decisions about the provision of health care services. This report is intended as a
reference and not as a substitute for clinical judgment.

This report may be used, in whole or in part, as the basis for the development of clinical practice
guidelines and other quality enhancement tools, or as a basis for reimbursement and coverage
policies. AHRQ or U.S. Department of Health and Human Services endorsement of such
derivative products may not be stated or implied.

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This document is in the public domain and may be used and reprinted without permission except
those copyrighted materials noted for which further reproduction is prohibited without the
specific permission of copyright holders.


Suggested Citation:
Berkman ND, Bulik CM, Brownley KA, Lohr KN, Sedway JA, Rooks A, Gartlehner G.
Management of Eating Disorders. Evidence Report/Technology Assessment No. 135. (Prepared
by the RTI International-University of North Carolina Evidence-Based Practice Center under
Contract No. 290-02-0016.) AHRQ Publication No. 06-E010. Rockville, MD: Agency for
Healthcare Research and Quality. April 2006.

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Preface


Practice Centers (EPCs), sponsors the development of evidence reports and technology
assessments to assist public- and private-sector organizations in their efforts to improve the
quality of health care in the United States. The report topic was nominated by the American
Psychiatric Association (APA) and the Laureate Psychiatric Clinic and Hospital. Funding for this
report was provided by the Office of Research on Women’s Health at the National Institutes of
Health (NIH) and the Health Resources and Services Administration. The reports and
assessments provide organizations with comprehensive, science-based information on common,
costly medical conditions and new health care technologies. The EPCs systematically review the
relevant scientific literature on topics assigned to them by AHRQ and conduct additional
analyses when appropriate prior to developing their reports and assessments.
To bring the broadest range of experts into the development of evidence reports and health
technology assessments, AHRQ encourages the EPCs to form partnerships and enter into
collaborations with other medical and research organizations. The EPCs work with these partner
organizations to ensure that the evidence reports and technology assessments they produce will
become building blocks for health care quality improvement projects throughout the Nation. The
reports undergo peer review prior to their release.
AHRQ expects that the EPC evidence reports and technology assessments will inform
individual health plans, providers, and purchasers as well as the health care system as a whole by
providing important information to help improve health care quality.
We welcome comments on this evidence report. They may be sent by mail to the Task Order
Officer named below at: Agency for Healthcare Research and Quality, 540 Gaither Road,
Rockville, MD 20850, or by e-mail to epc@ahrq.gov.


Carolyn M. Clancy, M.D.
Director
Agency for Healthcare Research and Quality


Vivian W. Pinn, M.D.
Director
Office of Research on Women’s Health
National Institutes of Health


Sabrina A. Matoff-Stepp, M.A.
Director
Office of Women’s Health
Health Resources and Services Administration


The Agency for Healthcare Research and Quality (AHRQ), through its Evidence-Based
Jean Slutsky, P.A., M.S.P.H.
Director, Center for Outcomes and Evidence
Agency for Healthcare Research and Quality

Beth A. Collins Sharp, R.N., Ph.D.
Acting Director, EPC Program
Agency for Healthcare Research and Quality
Marian James, Ph.D.
EPC Program Task Order Officer
Agency for Healthcare Research and Quality

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Structured Abstract
Objectives. The RTI International—University of North Carolina at Chapel Hill Evidence-based
Practice Center (RTI-UNC EPC) systematically reviewed evidence on efficacy of treatment for
anorexia nervosa (AN), bulimia nervosa (BN), and binge eating disorder (BED), harms
associated with treatments, factors associated with the treatment efficacy and with outcomes of
these conditions, and whether treatment and outcomes for these conditions differ by
sociodemographic characteristics.

Data Sources. We searched MEDLINE®, the Cumulative Index to Nursing and Applied Health
(CINAHL), PSYCHINFO, the Educational Resources Information Center (ERIC), the National
Agricultural Library (AGRICOLA), and Cochrane Collaboration libraries.

Review Methods. We reviewed each study against a priori inclusion/exclusion criteria. For
included articles, a primary reviewer abstracted data directly into evidence tables; a second
senior reviewer confirmed accuracy. We included studies published from 1980 to September,
2005, in all languages. Studies had to involve populations diagnosed primarily with AN, BN, or
BED and report on eating, psychiatric or psychological, or biomarker outcomes.

Results. We report on 30 treatment studies for AN, 47 for BN, 25 for BED, and 34 outcome
studies for AN, 13 for BN, 7 addressing both AN and BN, and 3 for BED.
The AN literature on medications was sparse and inconclusive. Some forms of family
therapy are efficacious in treating adolescents. Cognitive behavioral therapy (CBT) may reduce
relapse risk for adults after weight restoration.
For BN, fluoxetine (60 mg/day) reduces core bulimic symptoms (binge eating and purging)
and associated psychological features in the short term. Individual or group CBT decreases core
behavioral symptoms and psychological features in both the short and long term. How best to
treat individuals who do not respond to CBT or fluoxetine remains unknown.
In BED, individual or group CBT reduces binge eating and improves abstinence rates for up
to 4 months after treatment; however, CBT is not associated with weight loss. Medications may
play a role in treating BED patients. Further research addressing how best to achieve both
abstinence from binge eating and weight loss in overweight patients is needed.
Higher levels of depression and compulsivity were associated with poorer outcomes in AN;
higher mortality was associated with concurrent alcohol and substance use disorders. Only
depression was consistently associated with poorer outcomes in BN; BN was not associated with
an increased risk of death. Because of sparse data, we could reach no conclusions concerning
BED outcomes.
No or only weak evidence addresses treatment or outcomes difference for these disorders.

Conclusions. The literature regarding treatment efficacy and outcomes for AN, BN, and BED is
of highly variable quality. In future studies, researchers must attend to issues of statistical power,
research design, standardized outcome measures, and sophistication and appropriateness of
statistical methodology.

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Contents
Executive Summary...........................................................................................................................1

Evidence Report...............................................................................................................................9

Chapter 1. Introduction.....................................................................................................................9
Scope of the Problem...................................................................................................................9
Anorexia Nervosa........................................................................................................................9
Clinical Characteristics..........................................................................................................9
Diagnostic Criteria.................................................................................................................9
Epidemiology.........................................................................................................................9
Etiology..................................................................................................................................11
Course of Illness ....................................................................................................................12
Treatment...............................................................................................................................12
Bulimia Nervosa..........................................................................................................................13
Clinical Characteristics..........................................................................................................13
Diagnostic Criteria.................................................................................................................13
Epidemiology.........................................................................................................................15
Etiology..................................................................................................................................15
Course of Illness ....................................................................................................................16
Treatment...............................................................................................................................16
Eating Disorders Not Otherwise Specified (Binge Eating Disorder).........................................16
Clinical Characteristics..........................................................................................................16
Diagnostic Criteria.................................................................................................................17
Epidemiology.........................................................................................................................18
Etiology..................................................................................................................................18
Course of Illness ....................................................................................................................18
Treatment...............................................................................................................................18
Production of This Evidence Report............................................................................................18
Organization...........................................................................................................................18
Technical Expert Panel..........................................................................................................19
Uses of This Report ...............................................................................................................19

Chapter 2. Methods...........................................................................................................................21
Key Questions and Analytic Framework.....................................................................................21
Key Questions........................................................................................................................21
Literature Review Methods..........................................................................................................22
Inclusion and Exclusion Criteria............................................................................................22
Literature Search and Retrieval Process................................................................................24
Literature Synthesis .....................................................................................................................26
Development of Evidence Tables and Data Abstraction Process..........................................26
Quality and Strength of Evidence Evaluation........................................................................27
Peer Review Process....................................................................................................................29

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Chapter 3. Results: Anorexia Nervosa..............................................................................................37
Overview of Included Studies......................................................................................................37
Participants.............................................................................................................................40
Key Question 1: Treatment Efficacy .................................................................................................42
Medication Trials...................................................................................................................46
Behavioral Intervention Trials (for Anorexia Nervosa).........................................................46
Key Question 2: Harms of Treatments for Anorexia Nervosa ....................................................52
Key Question 3: Factors Associated With Treatment Efficacy...................................................53
Key Question 4: Treatment Efficacy by Subgroups....................................................................54

Chapter 4. Results: Bulimia Nervosa................................................................................................57
Overview of Included Studies......................................................................................................57
Participants.............................................................................................................................59
Key Question 1: Treatment Efficacy ...........................................................................................60
Medication-only trials............................................................................................................60
Medication Plus Behavioral Intervention Trials....................................................................70
Behavioral Intervention Trials (for Bulimia Nervosa)...........................................................74
Key Question 2: Harms of Treatment for Bulimia Nervosa........................................................84
Key Question 3: Factors Associated With Treatment Efficacy...................................................84
Medication Trials...................................................................................................................84
Behavioral Intervention Trials...............................................................................................87
Self-help Trials.......................................................................................................................87
Other Interventions................................................................................................................87
Key Question 4: Treatment Efficacy by Subgroups....................................................................87

Chapter 5. Results: Binge Eating Disorder.......................................................................................89
Overview of Included Studies......................................................................................................89
Participants.............................................................................................................................91
Key Question 1: Treatment Efficacy ...........................................................................................92
Medication-only trials............................................................................................................92
Medication Plus Behavioral Intervention Trials....................................................................98
Behavioral Interventions Trials..............................................................................................100
Key Question 2: Harms of Treatment for Binge Eating Disorder...............................................106
Key Question 3: Factors Associated With Treatment Efficacy...................................................106
Key Question 4: Treatment Efficacy Subgroups.........................................................................106

Chapter 6. Outcomes of Eating Disorders........................................................................................109
Anorexia Nervosa........................................................................................................................112
Key Question 5: Factors associated with outcomes...............................................................112
Key Question 6: Outcome Difference by Sex, Gender, Age, Race, Ethnicity, or
Cultural Group.................................................................................................................125
Bulimia Nervosa..........................................................................................................................126
Key Question 5: Factors Asociated with Outcomes....................................................................126
Key Question 6: Outcome Difference by Sex, Gender, Age, Race, Ethnicity or
Cultural Group.................................................................................................................132

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Chapter 7. Discussion.......................................................................................................................135
Critical Findings and Implications for Treatment of Eating Disorders ......................................135
Quality of Literature and Strength of Evidence.....................................................................135
Managing Patients with Medication Alone............................................................................138
Managing Patients with Behavioral Interventions Alone......................................................138
Managing Patients with Combination Interventions..............................................................139
Managing Patients with Novel Interventions.........................................................................139
Reducing Mortality................................................................................................................139
Methods and Other Deficiencies in Reviewed Studies and Recommendations to Overcome
Them......................................................................................................................................139
Sample Sizes, Attrition, and Statistical Power.......................................................................139
Study Design and Statistical Analysis Issues.........................................................................140
Reporting Issues.....................................................................................................................141
Future Research Needs ................................................................................................................142
Gaps in the Literature for Interventions.................................................................................142
Gaps in the Literature for Certain Types of Patients .............................................................144
Gaps in the Overall Evidence Base........................................................................................146
Issues in Outcomes Research.................................................................................................147
Conclusions..................................................................................................................................149

References and Included Studies.......................................................................................................151

Figures

Figure 1. Analytic framework............................................................................................................22
Figure 2. Eating disorders article disposition ....................................................................................25

Tables

Table 1. Diagnostic criteria: anorexia nervosa ..................................................................................10
Table 2. Diagnostic criteria: bulimia nervosa....................................................................................14
Table 3. Diagnostic criteria: binge eating disorders ..........................................................................17
Table 4. Eating disorders literature searches: inclusion and exclusion criteria.................................23
Table 5. Diagnostic and outcome measures used in randomized controlled trials and
outcome studies.............................................................................................................................30
Table 6. Reasons for poor quality ratings and number of trials with poor ratings: anorexia
nervosa..........................................................................................................................................38
Table 7. Dropout rates for randomized controlled trials: anorexia nervosa ......................................41
Table 8. Results from medication trials: anorexia nervosa................................................................43
Table 9. Results from behavioral intervention trials in adults: anorexia nervosa..............................47



Binge Eating Disorder..................................................................................................................133
Key Question 5: Factors Associated with Outcomes.............................................................133
Key Question 6: Outcome Difference by Sex, Gender, Age, Race, Ethnicity or
Cultural Group.................................................................................................................134

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Table 10. Results from behavioral intervention trials in adolescents only and adolescents
and adults combined: anorexia nervosa........................................................................................49
Table 11. Adverse events reported: anorexia nervosa.......................................................................53
Table 12. Reasons for poor quality ratings and number of trials with poor ratings: bulimia
nervosa trials.................................................................................................................................58
Table 13. Dropout rates for randomized controlled trials: bulimia nervosa......................................60
Table 14. Results from medication trials: bulimia nervosa...............................................................64
Table 15. Results from medication plus behavioral intervention trials: bulimia nervosa .................71
Table 16. Result from behavioral intervention trials: bulimia nervosa .............................................75
Table 17. Results of self-help trials, no medication: bulimia nervosa...............................................81
Table 18. Results of other trials: bulimia nervosa.............................................................................83
Table 19. Adverse events reported: bulimia nervosa trials................................................................85
Table 20. Reasons for poor quality ratings and number of trials with poor ratings
binge eating disorder ....................................................................................................................90
Table 21. Dropout rates for randomized controlled trials: binge eating disorder..............................93
Table 22. Results from medication trials: binge eating disorder.......................................................95
Table 23. Results from medication plus behavioral intervention trials: binge eating disorder .........99
Table 24. Results from behavioral intervention trials, no medication: binge eating disorder...........101
Table 25. Results from self-help trials, no medication: binge eating disorder..................................103
Table 26. Results from other trials: binge eating disorder.................................................................104
Table 27. Adverse events reported: binge eating disorder.................................................................107
Table 28. Outcome studies: reasons for poor quality ratings and number of poor ratings
by disease type..............................................................................................................................110
Table 29. Eating-related outcomes: anorexia nervosa.......................................................................113
Table 30. Psychological outcomes: anorexia nervosa ......................................................................119
Table 31. Biomarker outcomes: anorexia nervosa ............................................................................121
Table 32. Mortality outcomes: anorexia nervosa ..............................................................................122
Table 33. Eating-related outcomes: bulimia nervosa.........................................................................127
Table 34. Psychological outcomes: bulimia nervosa ........................................................................130
Table 35. Biomarker outcomes: bulimia nervosa .............................................................................131
Table 36. Mortality outcomes: bulimia nervosa ...............................................................................132
Table 37. Strength of evidence concerning four treatment key questions.........................................136
Table 38. Strength of evidence concerning two outcomes key questions.........................................137

Appendixes

Appendix A: Exact Search Strings
Appendix B: Sample Data Collection Forms
Appendix C: Evidence Tables
Appendix D: List of Excluded Articles
Appendix E: Acknowledgments

Appendixes and Evidence Tables for this report are provided electronically at
http://www.ahrq.gov/downloads/pub/evidence/pdf/eatingdisorders/eatdis.pdf.

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Executive Summary
Introduction
The RTI International–University of North Carolina at Chapel Hill Evidence-based Practice
Center (RTI-UNC EPC) conducted a systematic review of the literature on key questions
concerning anorexia nervosa (AN), bulimia nervosa (BN), and eating disorders not otherwise
specified (EDNOS) (focusing on binge eating disorder [BED]) to address questions posed by the
American Psychiatric Association and Laureate Psychiatric Hospital through the Agency for
Healthcare Research and Quality (AHRQ). Funding was provided by AHRQ, the Office of
Research on Women’s Health at the National Institutes of Health, and the Health Resources and
Services Administration. We received guidance and input from a Technical Expert Panel (TEP).
We systematically reviewed the evidence on two categories of issues—treatment and
outcomes for AN, BN, and BED—in six key questions (KQs): (1) efficacy of treatment, (2)
harms associated with treatment, (3) factors associated with the efficacy of treatment, (4)
whether efficacy of treatment differs by sex, gender, age, race, ethnicity, or cultural group, (5)
factors associated with outcomes, and (6) whether outcomes differ by sex, gender, age, race,
ethnicity, or cultural group.
AN is marked by low body weight, fear of weight gain, disturbance in the way in which
one’s body size is perceived, denial of illness, or undue influence of weight on self-evaluation.
Although amenorrhea is a diagnostic criterion, it is of questionable relevance.
BN is characterized by recurrent episodes of binge eating in combination with some form of
compensatory behavior. Binge eating is the consumption of an uncharacteristically large amount
of food by social comparison coupled with a feeling of being out of control. Compensatory
behaviors include self-induced vomiting; misuse of laxatives, diuretics, or other agents; fasting;
and excessive exercise.
BED is marked by binge eating in the absence of compensatory behaviors, a series of
associated features of binge eating, and marked distress regarding binge eating. Overweight and
obesity are commonly seen in individuals with BED.
Although rigorous epidemiologic data are lacking in the United States, the mean prevalence
of AN is 0.3 percent, of subthreshold AN 0.37 percent to 1.3 percent, of BN 1.0 percent, and of
BED 0.7 percent to 3.0 percent. Mortality from AN is about 5 percent per decade of followup.
Treatment for severe AN can involve inpatient or partial hospitalization in costly specialized
settings. Inadequate insurance coverage often truncates the recommended duration of treatment.
Treatment costs for AN are higher than those for obsessive-compulsive disorder and comparable
to those for schizophrenia. In contrast, treatment for BN in the United States is typically on an
outpatient basis.
Methods
We searched MEDLINE®, the Cumulative Index to Nursing and Applied Health (CINAHL),
PSYCHINFO, the Educational Resources Information Center (ERIC), the National Agricultural
Library (AGRICOLA), and Cochrane Collaboration libraries. Based on key questions and
discussion with our TEP, we generated a list of article inclusion and exclusion criteria. We
reviewed studies of humans, ages 10 years and older, of both sexes, published in all languages
and from all nations, from 1980 to September 2005. Studies had to include populations
diagnosed primarily with AN, BN, or BED and to report on at least one of our outcomes

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categories of interest: eating-related behaviors, psychiatric and psychological outcomes, and
biomarker measures. We reviewed each abstract and article systematically against a priori
criteria to determine whether to include it in the review. One reviewer initially evaluated
abstracts for inclusion or exclusion. If that reviewer concluded that the article should be included
in the review, it was retained. Articles that the reviewer determined did not meet our criteria
were re-reviewed by a senior reviewer who could include the article if she disagreed with the
initial determination. We assigned each excluded article a reason for exclusion.
The RTI-UNC EPC team abstracted data from included articles directly into evidence tables.
For both the treatment and the outcomes literatures, a primary reviewer abstracted data directly
into evidence tables; a second (senior) reviewer confirmed accuracy, completeness, and
consistency. The two staff reconciled all disagreements about information in evidence tables.
Each abstractor independently evaluated study quality. Because of differences in the
treatment and outcomes literature, we evaluated the two bodies of literature using separate
criteria. For the treatment literature, our evaluation used 25 items in 11 categories: (1) research
aim/study question, (2) study population, (3) randomization, (4) blinding, (5) interventions, (6)
outcomes, (7) statistical analysis, (8) results, (9) discussion, (10) external validity, and (11)
funding/sponsorship. For the outcomes literature, we evaluated the evidence against 17 items in
8 categories: (1) research aim/study question, (2) study population, (3) eating disorder diagnosis
method, (4) study design, (5) statistical analysis, (6) results/outcome measurement, (7) external
validity, and (8) discussion.
We focused our analysis on studies that received fair or good quality ratings. This included
19 studies discussed in 22 articles concerning treatment for AN: 38 studies discussed in 48
articles concerning treatment for BN: 20 studies discussed in 21 articles concerning treatment for
BED: 26 studies discussed in 32 articles concerning outcomes for AN: 9 studies discussed in 13
articles concerning outcomes for BN: 7 studies discussed in 7 articles concerning outcomes for
both AN and BN: and 3 studies discussed in 3 articles concerning outcomes for BED.
Results
Treatment Studies
Anorexia Nervosa. We divided the treatment literature into medication-only (generally in
the context of clinical management or hospitalization), medication plus behavioral intervention,
and behavioral intervention only for either adults or adolescents. The literature regarding
medication treatments for AN is sparse and inconclusive. The vast majority of studies had small
sample sizes and rarely had adequate statistical power to allow for definitive conclusions.
Although studies did include medication administered during or after inpatient intervention, no
AN studies that systematically combined medication with behavioral interventions met our
inclusion criteria, revealing a substantial gap in the literature.
In the behavioral intervention literature, preliminary evidence suggests that cognitive
behavioral therapy (CBT) may reduce relapse risk for adults with AN after weight restoration.
Sufficient evidence does not exist to determine whether CBT has any effect during the acute
phase of the illness, and one study, also requiring replication, showed that a manual-based
treatment combining elements of sound clinical management and supportive psychotherapy by a
specialist was more effective than CBT during the acute phase. Family therapy as currently
conceptualized does not appear to be effective with adults with AN with longer duration of
illness. Specific forms of family therapy initially focusing on parental control of renutrition is

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efficacious in treating AN in adolescents and leads to clinically meaningful weight gain and
psychological change. The lack of follow-up data compromises our ability to determine the
extent to which treatment gains are maintained.
Bulimia Nervosa. In medication trials, fluoxetine (60 mg/day) administered for 6 weeks to
18 weeks reduced the core bulimia symptoms of binge eating and purging and associated
psychological features in the short term. The 60 mg dose performs better than lower doses and is
associated with prevention of relapse at 1 year. Evidence for the long-term effectiveness of
relatively brief medication treatment does not exist. The optimal duration of treatment and the
optimal strategy for maintenance of treatment gains are unknown.
Studies that combine drugs and behavioral interventions provide only preliminary evidence
regarding the optimal combination of medication and psychotherapy or self-help. How best to
treat individuals who do not respond to CBT or fluoxetine remains a major shortcoming of the
literature. For behavioral interventions for BN, CBT administered individually or in group
format is effective in reducing the core behavioral symptoms of binge eating and purging and
psychological features in both the short and long term. Further evidence is required to establish
the role for self-help in reducing bulimic behaviors.
Binge Eating Disorder. For BED, we addressed two critical outcomes—decrease in binge
eating and decrease in weight in overweight individuals. Various medications were studied,
including selective serotonin reuptake inhibitors (SSRIs); a combined serotonin, dopamine, and
norepinephrine uptake inhibitor; tricyclic antidepressants; an anticonvulsant; and one appetite
suppressant. In short-term trials, SSRIs led to greater rates of reduction in target eating,
psychiatric and weight symptoms, and severity of illness than placebo controls. However, in the
absence of clear endpoint data, and in the absence of data regarding abstinence from binge
eating, we cannot judge the magnitude of the clinical impact of these interventions. Moreover, in
the absence of follow-up data after drug discontinuation, we do not know whether observed
changes in binge eating, depression, and weight persist.
The combination of CBT plus medication may improve both binge eating and weight loss,
although sufficient trials have not been done to determine definitively which medications are
best at producing and maintaining weight loss. Moreover, the optimal duration of medication
treatment for sustained weight loss has not yet been addressed empirically.
Collectively, clinical trials incorporating CBT for BED indicated that CBT decreases either
the number of binge days or the actual number of reported binge episodes. CBT leads to greater
rates of abstinence than does a waiting list control approach when administered either
individually or in group format, and this abstinence persists for up to 4 months posttreatment.
CBT also improves the psychological aspects of BED, such as ratings of restraint, hunger, and
disinhibition. Results are mixed as to whether CBT improves self-rated depression in this
population. Finally, CBT does not appear to produce decreases in weight.
Various forms of self-help were efficacious in decreasing binge days, binge eating episodes,
and psychological features associated with BED. Self-help also led to greater abstinence from
binge eating than waiting list; short-term abstinence rates approximate those seen in face-to-face
psychotherapy trials.
Strength of Evidence in Treatment Literature. We graded the strength of the body of
evidence for each question separately. For efficacy of treatment (KQ 1), we graded evidence for
AN treatment as weak, that for BN medication and behavioral interventions as strong, and that
for BED therapies as moderate. For harms associated with treatment (KQ 2), we graded
medication interventions for BN and BED as consistently strong; the literatures for all AN

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interventions and all other BN and BED interventions were graded as weak to nonexistent
because many studies failed to address harms associated with treatment. For factors associated
with efficacy of treatment (KQ 3), with the exception of behavioral interventions for BN, which
we graded as moderate, we graded the literature uniformly as weak. No published literature
provided evidence on whether the efficacy of treatment for these conditions differs by
sociodemographic factors (KQ 4). Overall, the literature on the treatment of AN in particular was
deficient.
Outcomes Literature
Outcomes of Eating Disorders. One prospective cohort study, conducted in Sweden,
followed individuals with AN in the community. Over a 10-year period, approximately half of
the group had fully recovered; a small percentage continued to suffer from AN, and the
remainder still had other eating disorders. Members of the AN group no longer differed from
those in the comparison group in terms of weight, but they continued to be more depressed and
to suffer from a variety of personality disorders, obsessive-compulsive disorder, Asperger
syndrome, and autism spectrum disorders.
The remaining AN studies followed patient populations. Typically, at least one-half of the
patients no longer suffered from AN at followup. However, many continued to have other eating
disorders such as BN or EDNOS, and mortality was significantly higher than would be expected
in the population matched by sex and age. Factors associated with recovery or good outcomes
included lower levels of depression and compulsivity. Factors associated with increased
mortality included concurrent alcohol and substance use disorders.
All of the BN outcomes studies followed patient populations. This literature emphasizes
comparisons of various definitions of disease outcomes and diagnostic subtypes. Generally, more
than one-half of the patients followed no longer had a BN diagnosis at the end of the study. A
substantial percentage continued to suffer from other eating disorders, but BN was not associated
with an increased mortality risk. A limited number of analyses uncovered factors significantly
associated with outcomes of this disease, but only depression was consistently associated with
worse outcomes.
Only sparse evidence addresses factors associated with BED outcomes. The three included
studies have vastly different designs and research questions; more importantly, they do not
converge on any systematic findings. Recalling that no studies of EDNOS outcomes exist, we
conclude that the literature regarding outcomes of both EDNOS in general and BED in particular
is seriously lacking; we believe that no conclusions can be drawn about factors influencing
outcomes of these disorders.
Age of AN disease onset was examined in several AN outcomes studies. However, the
relation between this variable and outcomes was mixed. No additional differences by participant
sex, gender, age, race, ethnicity, or cultural group emerged from the AN, BN, or BED outcomes
literature.
Strength of Evidence in Outcomes Literature. The strength of the evidence addressing
factors associated with outcomes among individuals with AN and BN is moderate. In contrast,
given the limited information about factors related to outcomes among individuals with BED
(KQ 5), we rated BED evidence as weak. We used the body of literature concerning KQ 5 to
examine differences in outcomes by sociodemographic factors (KQ 6). We graded the AN
literature as weak and the BN and BED literature as nonexistent.

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5
Discussion
In conclusion, the literature regarding treatment efficacy and outcome for AN, BN, and BED
is of highly variable quality. In the treatment literature, the largest deficiency rests with treatment
efficacy for AN where the literature was weakest. Future studies require large numbers of
participants, multiple sites, appropriate biomarker outcomes, and clear delineation of the age of
participants. For BN, future studies should address novel treatments for the disorder, optimal
duration of intervention, and optimal approaches for those who do not respond to medication or
CBT. For BED, future studies should identify interventions that are effective for both elimination
of binge eating and reduction of weight (in overweight individuals), optimal duration of
intervention, and effective strategies for prevention of relapse. For all three disorders,
exploration of additional treatment approaches is warranted. In addition, for all three disorders,
greater attention must be paid to factors influencing outcomes, harms associated with treatment,
and differential efficacy by sex, gender, age, race, ethnicity, or cultural group.
For all three disorders, consensus definitions of remission, recovery, and relapse are
essential. Greater attention to disease presentations currently grouped under the heading of
EDNOS is required for both treatment and outcome literature. For outcome studies, especially
for BN and BED, population-based cohort studies with comparison groups and adequate
durations of followup are required. For both future treatment and outcome studies, researchers
must carefully attend to issues of statistical power, research design including the use of similar
outcome measures across studies, and sophistication and appropriateness of statistical analyses.