Purging disorder: a comparison to established eating disorders with purging behaviour

Estimation of meal portions in bulimia nervosa compared to anorexia nervosa and healthy controls

PURPOSE

Bulimia nervosa (BN) and anorexia nervosa (AN) are potentially life-threatening eating disorders (ED) that primarily affect young people, mostly women. The central common pathology is linked to the relationship with food and with abnormalities in food intake. A previous study indicated that individuals with AN tend to overestimate food portion sizes compared to healthy controls (HC), but no study has investigated these patterns in BN, which was the objective of this study.

METHODS

Women with BN (27), AN (28), and HC (27) were asked to rate different meal portion sizes in two conditions: as if they were supposed to eat them (intent-to-eat condition) or in general (general condition). BN results were compared to HC and AN using mixed model analyses.

RESULTS

BN showed larger estimations compared to HC, while smaller estimations compared to AN. These differences were found mostly for intermediate portion sizes. No difference for conditions (intent-to-eat; general) was found between groups.

CONCLUSION

When estimating food portion sizes, individuals with BN seem to fall intermediately between HC and AN. ED symptoms in BN were most strongly associated with higher portion estimation. This might therefore reflect one aspect of the cognitive distortions typically seen also in AN. A therapeutic option could include the frequent visual exposure to increasing portions of food, what may serve to recalibrate visual perceptions of what a "normal-sized" portion of food looks like.

LEVEL OF EVIDENCE

Level II: Evidence obtained from well-designed controlled trials without randomization.

Evaluating the predictive validity of purging disorder by comparison to bulimia nervosa at long-term follow-up

OBJECTIVE

The current study sought to examine the predictive validity of the purging disorder diagnosis at long-term follow-up by comparing naturalistic outcomes with bulimia nervosa.

METHOD

Women with purging disorder (N = 84) or bulimia nervosa (N = 133) who had completed comprehensive baseline assessments as part of one of three studies between 2000 and 2012 were sought for follow-up assessment. Nearly all (94.5%) responded to recruitment materials and 150 (69% of sought sample; 83.3% non-Hispanic white; 33.40 [7.63] years old) participated at an average of 10.59 (3.71) years follow-up. Participants completed the Eating Disorder Examination, the Structured Clinical Interview for DSM-IV, and a questionnaire battery. Diagnostic groups were compared on eating disorder (illness status, recovery status, and eating pathology) and related outcomes. Group differences in predictors of outcome were explored.

RESULTS

There were no significant differences in eating disorder presence (p = .70), recovery status (p = .87), and level of eating pathology (p = .17) between diagnostic groups at follow-up. Post hoc equivalence tests indicated group differences were smaller than a medium effect size (p's ≤ .005). Groups differed in diagnosis at follow-up (p = .002); diagnostic stability was more likely than cross-over to bulimia nervosa for women with baseline purging disorder (p = .004).

DISCUSSION

Although purging disorder and bulimia nervosa do not differ in long-term outcomes, the relative stability in clinical presentation suggests baseline group differences in clinical presentation may be useful in augmenting treatments for purging disorder.

PUBLIC SIGNIFICANCE STATEMENT

While purging disorder is classified as an "other specified" eating disorder, individuals who experience this disorder have comparable negative long-term outcomes as those with bulimia nervosa. This highlights the importance of screening for and treating purging disorder as a full-threshold eating disorder.

Where does purging disorder lie on the symptomatologic and personality continuum when compared to other eating disorder subtypes? Implications for the DSM

OBJECTIVES

To assess the clinical significance and distinctiveness of purging disorder (PD) from other eating disorder (ED) diagnoses.

METHOD

Participants included 3127 women consecutively admitted to an ED treatment centre (246 PD, 465 anorexia nervosa restrictive [AN-R], 327 AN-binge purging [AN-BP], 1436 bulimia nervosa [BN], 360 binge eating disorder [BED], 177 atypical AN and 116 unspecified feeding or eating disorder [UFED]) who were diagnosed according to DSM-5 criteria. Additionally, 822 control participants were recruited from the community. All participants completed measures assessing ED symptoms (EDI-2), general psychopathology (SCL-90-R) and personality (TCI-R).

RESULTS

Patients with PD, when compared to controls, scored significantly higher on the EDI-2 and SCL-90-R, and most TCI-R dimensions. Most of the significant differences between PD and the other ED diagnoses emerged between PD and AN-R, followed by Atypical-AN, UFED, AN-BP and BED, with patients with PD typically reporting higher scores on the EDI-2 and SCL-90-R subscales. Significant differences between PD and BN were also present, but to a lesser extent. The findings for personality varied amongst the different ED diagnoses.

CONCLUSIONS

PD is a clinically significant disorder, which seems to be more similar to BN than it is to AN and the other ED subtypes.

A naturalistic, long-term follow-up of purging disorder

BACKGROUND

The DSM-5 introduced purging disorder (PD) as an other specified feeding or eating disorder characterized by recurrent purging in the absence of binge eating. The current study sought to describe the long-term outcome of PD and to examine predictors of outcome.

METHODS

Women (N = 84) who met research criteria for PD completed a comprehensive battery of baseline interview and questionnaire assessments. At an average of 10.24 (3.81) years follow-up, available records indicated all women were living, and over 95% were successfully located (n = 80) while over two-thirds (n = 58) completed follow-up assessments. Eating disorder status, full recovery status, and level of eating pathology were examined as outcomes. Severity and comorbidity indicators were tested as predictors of outcome.

RESULTS

Although women experienced a clinically significant reduction in global eating pathology, 58% continued to meet criteria for a DSM-5 eating disorder at follow-up. Only 30% met established criteria for a full recovery. Women reported significant decreases in purging frequency, weight and shape concerns, and cognitive restraint, but did not report significant decreases in depressive and anxiety symptoms. Quality of life was impaired in the physical, psychological, and social domains. More severe weight and shape concerns at baseline predicted meeting criteria for an eating disorder at follow-up. Other baseline severity indicators and comorbidity did not predict the outcome.

CONCLUSIONS

Results highlight the severity and chronicity of PD as a clinically significant eating disorder. Future work should examine maintenance factors to better adapt treatments for PD.

How do patients with eating disorders perceive and evaluate food portion sizes? A systematic review

OBJECTIVE

The selection of adequate portion sizes plays a key role in the nutritional treatment of eating disorders (EDs). There is limited knowledge concerning the estimation of portion sizes in individuals with EDs.

METHOD

We performed a systematic review according to the PRISMA statement to synthesise current evidence in this field. Of N = 584 hits, four full-texts were included in the qualitative synthesis.

RESULTS

While patients with anorexia nervosa (AN) tend to overestimate the size of energy-dense food items and small to medium sized meal portions, they do not show a different estimation compared to healthy controls when judging the amount of food pieces. Large portion sizes were associated with increased anxiety in patients with AN.

DISCUSSION

The overestimation of food portion sizes seems to be driven by attitudinal and/or higher cognitive factors associated with AN. Differences between the studies are discussed and suggestions for future studies are given.

A cluster analysis of purging disorder: Validation analyses with eating disorder symptoms, general psychopathology and personality

OBJECTIVES

To assess the natural grouping of Purging Disorder (PD) patients based on purging symptomatology and to evaluate the derived classes (a) against each other and (b) to a control group on a range of clinical and psychological measures.

METHOD

Participants included 223 PD women consecutively admitted to a tertiary ED treatment centre and 822 controls. Purging behaviours (self-induced vomiting, laxative and diuretic use) were used as indicators, while the EDI-2 (ED symptoms), the SCL-90-R (general psychopathology), and the TCI-R (personality traits) were used as validators.

RESULTS

Three distinct PD clusters emerged: Cluster 1 (only self-induced vomiting), Cluster 2 (self-induced vomiting and laxative use) and Cluster 3 (all purging methods). Significant differences between Cluster 1 and Cluster 3 were found for the EDI-2 drive for thinness and perfectionism subscales, and the TCI-persistence scale. All clusters differed significantly from the controls on all the EDI-2 and the SCL-90-R scales, but findings for the TCI-R scales were less consistent.

CONCLUSIONS

This study adds to a growing literature on the validity and distinctiveness of PD and provides evidence of dimensional symptom differences amongst PD clusters.

A review of purging disorder through meta-analysis

Although a growing body of research has examined Purging Disorder (PD), there remains a lack of conclusive evidence regarding the diagnostic validity of PD. This meta-analysis compared PD to DSM-5 eating disorders (i.e., Anorexia Nervosa [AN], Bulimia Nervosa [BN], and Binge Eating Disorder [BED]) and controls. A comprehensive literature search identified 38 eligible studies. Group differences on indicators of course of illness and both general and eating psychopathology were assessed using standardized effect sizes. Results supported the conceptualization of PD as a clinically significant eating disorder, but findings were less clear regarding its distinctiveness from other eating disorder diagnoses. More specifically, PD significantly differed from BN and BED in natural course of illness (g = .40-.54), and PD significantly differed from AN in treatment outcome (g = .27), with PD characterized by a better prognosis. Overall, PD was more similar to AN and BED on many dimensional measures of general and eating-related psychopathology, though PD was less severe than BN in most of these domains. PD, BN, and BED groups also evidenced similar frequencies of subjective binge episodes (SBEs), yet PD evidenced less frequent SBEs than AN. There is a clear need for future studies of PD to assess validators that have not been reported comprehensively in the literature, such as mortality, medical morbidity, and course of illness. Additionally, empirical classification studies are needed to inform future classifications of PD, particularly with regard to categorical differences between PD and other eating disorders. (PsycINFO Database Record

Disturbance of gut satiety peptide in purging disorder

OBJECTIVE

Little is known about biological factors that contribute to purging after normal amounts of food-the central feature of purging disorder (PD). This study comes from a series of nested studies examining ingestive behaviors in bulimic syndromes and specifically evaluated the satiety peptide YY (PYY) and the hunger peptide ghrelin in women with PD (n = 25), bulimia nervosa-purging (BNp) (n = 26), and controls (n = 26). Based on distinct subjective responses to a fixed meal in PD (Keel, Wolfe, Liddle, DeYoung, & Jimerson, ), we tested whether postprandial PYY response was significantly greater and ghrelin levels significantly lower in women with PD compared to controls and women with BNp.

METHOD

Participants completed structured clinical interviews, self-report questionnaires, and laboratory assessments of gut peptide and subjective responses to a fixed meal.

RESULTS

Women with PD demonstrated a significantly greater postprandial PYY response compared to women with BNp and controls, who did not differ significantly. PD women also endorsed significantly greater gastrointestinal distress, and PYY predicted gastrointestinal intestinal distress. Ghrelin levels were significantly greater in PD and BNp compared to controls, but did not differ significantly between eating disorders. Women with BNp endorsed significantly greater postprandial hunger, and ghrelin predicted hunger.

DISCUSSION

PD is associated with a unique disturbance in PYY response. Findings contribute to growing evidence of physiological distinctions between PD and BNp. Future research should examine whether these distinctions account for differences in clinical presentation as this could inform the development of specific interventions for patients with PD.

Disordered Eating Behaviors in Emerging Adults With Type 1 Diabetes: A Common Problem for Both Men and Women

INTRODUCTION

Emerging adults (EA) with disordered eating behaviors (DEBs) and Type 1 diabetes (T1D) are at increased risk for severe complications of T1D, and these behaviors have been reported in EA women with T1D. Few studies, though, have included men. This study assessed the prevalence of DEB in both EA men and women with T1D.

METHODS

DEB was measured with the diabetes-specific Diabetes Eating Problem Survey-Revised (DEPS-R); scores of 20 or greater indicate need for further evaluation for DEB.

RESULTS

A total of 27 women and 33 men (age range = 21 ± 2.5 years) completed the DEPS-R; 27% of women and 18% of men had scores of 20 or greater (p = .23). Hemoglobin A1c level was significantly higher in subjects with elevated DEPS-R scores (10.4 ± 2.1% vs. 7.8 ± 1.3%; p < .001), and DEPS-R scores correlated with increased body mass index values (r = 0.27, p < .05).

DISCUSSION

Clinicians should assess for DEB in both male and female emerging adults with T1D, especially overweight patients with poor glycemic control.

Purging behaviors and therapeutic prognosis of women with eating disorders treated in a healthcare context

Background/Objective: The evidence on efficacy of cognitive-behavioral interventions in Eating Disorders (ED) still shows inconclusive results with respect to the role of purging behaviors, more so in uncontrolled situations. Evolution of ED patients with and without purging behavior was studied 30 months after start of a multicomponent treatment. Method: 162 women (87 purging, 75 non-purging) treated in outpatient or hospitals + outpatient care units in Spain participated. The evaluation instruments were: BSQ, EAT-40, EDI, STAI, BDI and BITE. Results: At the beginning of the treatment, participants with purging behavior showed higher bulimic symptomatology, more body dissatisfaction, drive for thinness, perfectionism and ineffectiveness, anxiety and depressive symptomatology. After thirty months, intervention produced improvement in ED characteristics, emotional alterations and personal development variables, in both groups, but less in patients with no purging behavior. The effect of intervention was stronger in purging patients and variables with larger effect size: body dissatisfaction, bulimic symptomatology and anxiety. Conclusions: Purging behaviors must be considered in the design of these treatments with a view to prognosis.

The importance of loss of control while eating in adolescents with purging disorder

OBJECTIVE

Although many individuals with purging disorder (PD) report loss of control (LOC) eating, it is unclear whether they differ from those who do not, or from other eating disorders involving purging and/or LOC.

METHOD

We compared PD with LOC (PD-LOC), PD without LOC (PD-noLOC), bulimia nervosa (BN), and anorexia nervosa-binge/purge subtype (AN-B/P) on measures of eating-related and general psychopathology in treatment-seeking adolescents.

RESULTS

PD-LOC comprised ∼30% of PD diagnoses. PD-LOC and PD-noLOC did not differ from one another, or from BN and AN-B/P, on most measures of psychopathology, with some exceptions. PD-noLOC was similar to AN-B/P (p = 0.99) and significantly different from BN on eating concerns (p < 0.001), while PD-LOC was similar to BN, AN-B/P, and PD-noLOC on this measure (ps ≥ 0.06). PD-LOC reported higher self-esteem than BN, AN-B/P, and PD-noLOC (ps < 0.001).

DISCUSSION

PD was largely similar to other eating disorders characterized by purging, regardless of whether LOC eating was present. © 2016 Wiley Periodicals, Inc. (Int J Eat Disord 2016; 49:801-804).

Incremental validity of the episode size criterion in binge-eating definitions: An examination in women with purging syndromes

OBJECTIVE

Of the two primary features of binge eating, loss of control (LOC) eating is well validated while the role of eating episode size is less clear. Given the ICD-11 proposal to eliminate episode size from the binge-eating definition, the present study examined the incremental validity of the size criterion, controlling for LOC.

METHOD

Interview and questionnaire data come from four studies of 243 women with bulimia nervosa (n = 141) or purging disorder (n = 102). Hierarchical linear regression tested if the largest reported episode size, coded in kilocalories, explained additional variance in eating disorder features, psychopathology, personality traits, and impairment, holding constant LOC eating frequency, age, and body mass index (BMI). Analyses also tested if episode size moderated the association between LOC eating and these variables.

RESULTS

Holding LOC constant, episode size explained significant variance in disinhibition, trait anxiety, and eating disorder-related impairment. Episode size moderated the association of LOC eating with purging frequency and depressive symptoms, such that in the presence of larger eating episodes, LOC eating was more closely associated with these features. Neither episode size nor its interaction with LOC explained additional variance in BMI, hunger, restraint, shape concerns, state anxiety, negative urgency, or global functioning.

DISCUSSION

Taken together, results support the incremental validity of the size criterion, in addition to and in combination with LOC eating, for defining binge-eating episodes in purging syndromes. Future research should examine the predictive validity of episode size in both purging and nonpurging eating disorders (e.g., binge eating disorder) to inform nosological schemes. © 2016 Wiley Periodicals, Inc. (Int J Eat Disord 2016; 49:651-662).

The medical complications associated with purging

OBJECTIVE

Purging behaviors, including self-induced vomiting, laxative abuse, and diuretic abuse, are present across many of the eating disorders. Here we review the major medical complications of these behaviors.

METHOD

Although we identified over 100 scholarly articles describing medical complications associated with purging, most papers involved case studies or small, uncontrolled samples. Given the limited evidence base, we conducted a qualitative (rather than systematic) review to identify medical complications that have been attributed to purging behaviors.

RESULTS

Medical conditions affecting the teeth, esophagus, gastrointestinal system, kidneys, skin, cardiovascular system, and musculoskeletal system were identified, with self-induced vomiting causing the most medical complications.

DISCUSSION

Purging behavior can be associated with severe medical complications across all body systems. Mental health professionals should refer patients with purging behaviors to medical providers for screening and treatment as needed. The medical work-up for individuals with eating disorders should include a comprehensive metabolic panel, complete blood count, and a full body exam including the teeth to prevent severe complications. Medical providers should screen patients for purging behaviors and associated medical complications, even in the absence of an eating disorder diagnosis, to increase the detection of eating disorders. Recognizing the link between purging and medical complications can aid in identifying potential eating disorders, particularly those that often elude detection such as purging disorder.

Prevalence of and familial influences on purging disorder in a community sample of female twins

OBJECTIVE

Purging disorder (PD) was recently included as an otherwise specified feeding or eating disorder (OSFED) in the DSM-5; however, limited information is available on its prevalence, and its etiology is unknown.

METHOD

Data from 1,790 monozygotic and 1,440 dizygotic European American female twins (age range = 18-29 years) from the Missouri Adolescent Female Twin Study were used to investigate prevalence and familial influences for PD. A structured clinical interview assessed lifetime DSM-IV criteria for eating disorders and PD. After adjustment for age, twin correlations and biometrical twin models were used to estimate familial (i.e., genetic plus shared environmental) influences on PD.

RESULTS

One hundred and twenty one (3.77%; 95% CI: 3.14, 4.49) women met criteria for lifetime PD. Twin correlations suggested that genetic, shared environmental, and nonshared environmental factors influenced liability to PD. Nonshared environmental factors accounted for 56% [35%, 79%] of the variance in PD. Although familial effects accounted for a significant proportion of variance (44% [21%, 65%]), it was not possible to disentangle the independent contributions of additive genetic effects (20% [0%, 65%]) and shared environmental effects (24% [0%, 57%]).

DISCUSSION

PD is a prevalent form of eating pathology. Familial factors are relevant to the development of PD but do not demonstrate the magnitude of heritable factors found for other eating disorders.

Purging disorder: a pathway to death? A review of 11 cases

OBJECTIVE

With data from the Christina-Barz-Study, we report mortality rates and predictors of death in purging disorder (PurD) as well as additional information concerning the fatal cases.

METHOD

The study was conducted with 225 consecutively admitted inpatients during the years 1999-2005. About 9 years later, fatal cases were identified by local registration office records. The standardised mortality ratio (SMR) was calculated through mortality tables of the Federal Office of Statistics, Germany. To identify predictors of death, survival analyses were performed. Spouses, relatives or doctors of the deceased were consulted by interview or questionnaire for further information of pathogenesis and circumstances of death.

RESULTS

Six of the 225 sample individuals could not be located for the follow-up. Eleven of 219 former inpatients had died during the follow-up interval. The crude mortality rate was 5.0%. The SMR was 3.90 [95% confidence interval (2.05; 7.21)]. Age at admission and presence of one or more co-morbid somatic illnesses at admission were factors associated with a shorter time period until death.

DISCUSSION

Our data indicate that there is a higher number of deaths within the study population than expected. Paying particular attention to age and the severity of co-morbid somatic symptoms could improve the outcome of patients with PurD.