Prevalence of purging at age 16 and associations with negative outcomes among girls in three community-based cohorts

Clinical Factors Associated with Binge-Eating Episodes or Purging Behaviors in Patients Affected by Eating Disorders: A Cross-Sectional Study

The aim of the present study was to investigate the potential associations between clinical/socio-demographic variables and the presence of purging/binge-eating episodes in eating disorders (EDs). Clinical/socio-demographic variables and psychometric scores were collected. Groups of patients were identified according to the presence or absence of purging or objective binge-eating episodes (OBEs) and compared through t-test and chi-square tests. Binary logistic regression analyses were run. A sample of 51 ED outpatients was recruited. Patients with purging behaviors had a longer duration of untreated illness (DUI) (t = 1.672; p = 0.019) and smoked a higher number of cigarettes/day (t = 1.061; p = 0.030) compared to their counterparts. A lower BMI was associated with purging (OR = 0.881; p = 0.035), and an older age at onset showed a trend towards statistical significance (OR = 1.153; p = 0.061). Patients with OBEs, compared to their counterparts, were older (t = 0.095; p < 0.001), more frequently presented a diagnosis of bulimia or binge-eating disorder (χ2 = 26.693; p < 0.001), a longer duration of illness (t = 2.162; p = 0.019), a higher number of hospitalizations (t = 1.301; p = 0.012), and more often received a prescription for pharmacological treatment (χ2 = 7.864; OR = 6.000; p = 0.005). A longer duration of the last pharmacological treatment was associated with OBE (OR = 1.569; p = 0.046). In contrast to purging, OBE was associated with a more complicated and severe presentation of ED. A lower BMI and a later age at onset, as well as long-lasting previous pharmacological treatments, may predict the presence of purging/binging. Further research is needed to thoroughly characterize ED features and corroborate our preliminary findings.

Eating disorder-related functional impairment predicts greater depressive symptoms across one semester of college

Eating disorder (ED) behaviors and depression are associated with numerous negative outcomes, including lower quality of life and functional impairment. College women are at elevated risk for both. Prior research indicates ED behaviors, including binge eating, self-induced vomiting, and fasting, predict increases in future depressive symptoms. However, symptom heterogeneity in EDs is common, and all disordered eating, or its associated distress, cannot be captured by the endorsement of behaviors. Impairment that results from ED behaviors may be a comparable, or stronger, predictor of depressive symptoms. We sought to characterize the longitudinal relationship between ED-related functional impairment, ED behaviors, and depressive symptoms. College-aged women [N = 304; 72 % white, mean (SD) age = 18.45 (0.88)] completed an online survey in August (baseline), and then three months later in November (follow-up). Baseline ED-related functional impairment, but not baseline ED behaviors, significantly predicted depressive symptoms at follow-up, controlling for baseline depressive symptoms, negative affect, and body mass index. Findings indicate ED-related functional impairment is a risk factor for increases in depressive symptoms across one semester of college, irrespective of ED behavior engagement, weight status, and dispositional negative affect. Intervening upon ED-related functional impairment may reduce or prevent future depressive symptoms among college-aged women.

Differential genetic associations between dimensions of eating disorders and alcohol involvement in late adolescent twins

BACKGROUND

Twin studies have demonstrated shared genetic and environmental effects between eating disorders and alcohol involvement in adults and middle adolescents. However, fewer studies have focused on late adolescents or investigated a wide range of eating disorder dimensions and alcohol involvement subscales in both sexes. We examined genetic and environmental correlations among three eating disorder dimensions and two alcohol involvement subscale scores in late adolescent twins using bivariate twin models.

METHODS

Participants were 3568 female and 2526 male same-sex twins aged 18 years old from the Child and Adolescent Twin Study in Sweden. The Eating Disorder Inventory-2 (EDI) assessed the drive for thinness, bulimia, and body dissatisfaction. Alcohol involvement was assessed with the Alcohol Use Disorder Identification Test consumption (AUDIT-C) and problem (AUDIT-P) subscales.

RESULTS

Only phenotypic and twin correlations in female twins met our threshold for twin modeling. The proportion of total variance for each trait accounted for by additive genetic factors ranged from 0.50 to 0.64 in female twins, with the rest explained by nonshared environmental factors and measurement error. Shared environmental factors played a minimal role in the variance of each trait. The strongest genetic correlation (ra ) emerged between EDI bulimia and AUDIT-P (ra  = 0.46, 95% confidence interval: 0.37, 0.55), indicating that the proportion of genetic variance of one trait that was shared with the other trait was 0.21. Nonshared environmental correlations between eating disorder dimensions and alcohol involvement ranged from 0.03 to 0.13.

CONCLUSIONS

We observed distinct patterns of genetic and environmental effects for co-occurring eating disorder dimensions and alcohol involvement in female vs. male twins, supporting sex-specific treatment strategies for late adolescents with comorbid eating disorders and alcohol use disorder. Our findings emphasize the importance of assessing family history of multiple eating disorder dimensions while treating late adolescents with problematic alcohol use, and vice versa, to improve detection and treatment.

Analysis of symptom clusters amongst adults with anorexia nervosa: Key severity indicators

This study used cluster analysis to explore clinically relevant subgroups of adult patients with anorexia nervosa (AN). Patients were clustered based on their body mass index (BMI), eating disorder symptomatology, anxiety and depression symptoms and autistic characteristics. The difference between clusters in work and social functioning, duration of illness, bingeing and purging behaviour, previous hospitalisations and number of comorbidities was also investigated. Two meaningful clusters emerged: a higher symptoms cluster with more severe eating pathology, anxiety, depression, and more autistic traits, and a second cluster with lower symptoms. BMI did not make major contributions to cluster formation. The higher symptoms cluster also reported lower self-efficacy to change, more previous hospitalisations, comorbid diagnoses, binge eating and purging behaviours and use of psychotropic medication. Our findings suggest that weight alone may not be a significant severity indicator amongst inpatients with AN, and targeted treatment of AN should consider a broader range of symptom severity indicators.

Physical activity and disordered eating behaviours: Are Caribbean adolescents at risk?

Excessive physical activity (PA) has been linked to increased risk for disordered eating behaviours and eating disorders. This study investigates the relationship between PA and disordered eating behaviours and attitudes (DEBAs) among Jamaican adolescents. This cross-sectional study included 521 adolescents, 12-19 years. Anthropometric measurements were collected, and adolescents completed questionnaires on disordered eating behaviours (EAT-26), physical activity, self-esteem and affect. Associations were assessed using sex-specific mixed-effect linear and logistic regression models. Participants reported exercising an average of 3 days per week. Adolescents who exercised for a longer duration had greater odds of having elevated EAT-26 scores (at least 1 hour-OR = 2.04; 95% CI = 1.03, 4.06; p = .042), while a higher exercise frequency among males (3-5 days per week) was protective against DEBAs (OR 0.38; 95% CI = 0.16, 0.88; p = .025). Female adolescents reported higher prevalence of elevated EAT-26 scores than males (p < .01). Increased negative affect increased odds of an elevated EAT-26 score. Exercise duration and frequency play a role in disordered eating behaviours in Jamaican adolescents and vary by gender. Our findings have implications for weight management interventions and policies, encouraging healthcare providers to monitor PA levels as well as negative affect in adolescents who display disordered eating behaviours.

Longitudinal associations of trauma exposure with disordered eating: Lessons from the Great Smoky Mountains Study

Disordered eating is prevalent among trauma survivors, yet little is known about mechanisms underlying this relation. We explored cross-sectional and longitudinal associations of trauma exposure and posttraumatic stress disorder symptoms (PTSD) with disordered eating among 1,420 community-based youth participating in the Great Smoky Mountain Study. Participants were interviewed about trauma exposure, PTSD symptoms, and disordered eating at regular intervals throughout childhood, adolescence, and early adulthood. Our findings confirmed associations of all forms of trauma exposure (violent, sexual, and other) with disordered eating symptoms in childhood and adulthood, although the pattern of results varied by disordered eating symptom and trauma exposure type. Only non-sexual, non-violent trauma exposure in childhood had significant associations with any disordered eating symptoms in adulthood. Within childhood, trauma exposures but not PTSD symptoms showed significant longitudinal associations with bulimia nervosa symptoms and sustained appetite changes and preoccupation with eating. In adulthood, PTSD symptoms but not trauma exposures showed significant longitudinal associations only with bulimia nervosa symptoms. The association of specific PTSD clusters on bulimia nervosa symptoms was significant for reexperiencing, whereas hyperarousal symptoms trended toward significance. The impact of trauma exposures on disordered eating may vary by developmental period.

Binge eating and alcohol consumption: an integrative review

OBJECTIVE

To identify the relationship between binge eating and alcohol consumption.

METHODS

This is an integrative literature review of publications from 2015 to 2019, using the Pubmed, Cinhahl, Psynet, Lilacs, Embase and Web of Science virtual databases and the descriptors ("Binge-Eating" OR "Bulimia") AND Alcohol* in English, Spanish and Portuguese.

RESULTS

A total of 964 articles were found. After reading the titles and abstracts and excluding duplicates, 36 articles were included in the final sample (35 in English and one in Portuguese). They were grouped into three thematic categories: "sample profile and characterization", "genetic and environmental factors", and "emotions and behavior".

CONCLUSIONS

The data indicate the existence of a relationship between binge eating and alcohol use, and some factors were associated with this comorbidity. Still, there were few publications on the theme at the national level, indicating the need for developing more research. These findings may support therapeutic actions and strategies for identification of cases, embracing approaches and more effective treatments to meet the individual's biopsychosocial demands.

LEVEL OF EVIDENCE

Level V, narrative review.

A scientometric analysis of birth cohorts in South Asia: Way forward for Pakistan

The present study aims to: a) systematically map the of birth cohort studies from the South Asian region b) examine the major research foci and landmark contributions from these cohorts using reproducible scientometric techniques and c) offer recommendations on establishing new birth cohorts in Pakistan, building upon the strengths, weaknesses and gaps of previous cohorts. Bibliographic records for a total of 260 articles, published during through December 2018, were retrieved from the Web of Science (core database). All data were analysed using Microsoft Excel (2013), Web of Science platform and CiteSpace. A series of network analysis were then run for each time-period using the link reduction method and pathfinder network scaling. The co-cited articles were clustered into their homogeneous research clusters. The clusters were named using the Latent Semantic Indexing (LSI) method that utilized author keywords as source of names for these clusters. The scientometric analyses of original research output from these birth cohorts also paint a pessimistic landscape in Pakistan- where Pakistani sites for birth cohorts contributed only 31 publications; a majority of these utilized the MAL-ED birth cohort data. A majority of original studies were published from birth cohorts in India (156), Bangladesh (63), and Nepal (15). Out of these contributions, 31 studies reported data from multiple countries. The three major birth cohorts include prospective and multi-country MAL-ED birth cohort and The Pakistan Early Childhood Development Scale Up Trial, and a retrospective Maternal and infant nutrition intervention cohort. In addition to these, a few small-scale birth cohorts reported findings pertaining to neonatal sepsis, intrauterine growth retardation and its effects on linear growth of children and environmental enteropathy.

Polygenic Score for Body Mass Index Is Associated with Disordered Eating in a General Population Cohort

Background: Disordered eating (DE) is common and is associated with body mass index (BMI). We investigated whether genetic variants for BMI were associated with DE. Methods: BMI polygenic scores (PGS) were calculated for participants of the Avon Longitudinal Study of Parents and Children (ALSPAC; N = 8654) and their association with DE tested. Data on DE behaviors (e.g., binge eating and compensatory behaviors) were collected at ages 14, 16, 18 years, and DE cognitions (e.g., body dissatisfaction) at 14 years. Mediation analyses determined whether BMI mediated the association between the BMI-PGS and DE. Results: The BMI-PGS was positively associated with fasting (OR = 1.42, 95% CI = 1.25, 1.61), binge eating (OR = 1.28, 95% CI = 1.12, 1.46), purging (OR = 1.20, 95% CI = 1.02, 1.42), body dissatisfaction (Beta = 0.99, 95% CI = 0.77, 1.22), restrained eating (Beta = 0.14, 95% CI = 0.10, 1.17), emotional eating (Beta = 0.21, 95% CI = 0.052, 0.38), and negatively associated with thin ideal internalization (Beta = −0.15, 95% CI = −0.23, −0.07) and external eating (Beta = −0.19, 95% CI = −0.30, −0.09). These associations were mainly mediated by BMI. Conclusions: Genetic variants associated with BMI are also associated with DE. This association was mediated through BMI suggesting that weight potentially sits on the pathway from genetic liability to DE.

Association between prenatal maternal infection and disordered eating behaviours in adolescence: a UK population-based prospective birth cohort study

BACKGROUND

Prenatal infections have been proposed as a putative risk factor for a number of psychiatric outcomes across a continuum of severity. Evidence on eating disorders is scarce. We investigated whether exposure to prenatal maternal infections is associated with an increased risk of disordered eating and weight and shape concerns in adolescence in a large UK birth cohort.

METHODS

We used data from the Avon Longitudinal Study of Parents and Children. The primary exposure was maternal experience of infections at any time in pregnancy. Study outcomes were presence of any, monthly or weekly disordered eating at 14 and 16 years of age, and weight and shape concerns at 14 years. We defined the causal effect of the exposure on these outcomes using a counterfactual framework adjusting our analyses for a number of hypothesised confounders, and imputing missing confounder data using multiple imputation.

RESULTS

In total, 4884 children had complete exposure and outcome data at age 14 years, and 4124 at 16 years. Exposed children had a greater risk of reporting weekly disordered eating at both age 14 [risk difference (RD) 0.9%, 95% confidence interval (CI) -0.01 to 1.9, p = 0.08] and 16 (RD 2.3%, 95% CI 0.6-3.9, p < 0.01), though evidence of an association was weak at age 14 years. Exposed children also had greater weight and shape concerns at age 14 years (mean difference 0.15, 95% CI 0.05-0.26, p < 0.01).

CONCLUSIONS

Exposure to prenatal maternal infection is associated with greater risk of disordered eating in adolescence. This association could be explained by in utero processes leading to impaired neurodevelopment or altered immunological profiles. Residual confounding cannot be excluded.

Relationship between unhealthy weight control behaviors and substance use patterns among Korean adolescents: results from the 2017 national youth risk behavior survey

OBJECTIVE

Unhealthy weight control behaviors (UWCBs) can lead to numerous health problems. Adolescents who engage in UWCB are more likely to abuse substances than other adolescents. However, few studies have examined the relationship between UWCB and substance use, despite the fact that their co-occurrence can result in greater morbidity and mortality. The aim of this study was to examine the association between UWCB and substance use patterns among Korean adolescents using nationally representative data.

STUDY DESIGN

This study involved an analysis of statistical data collected from 27,284 adolescent participants (13-18 years old) in the 2017 Korean Youth Risk Behavior Web-based Survey.

METHODS

The Chi-squared test and multiple logistic regression analysis were performed to demonstrate the association between substance use patterns (energy drink intake, alcohol use, cigarette smoking, electronic cigarette use, and drug use) and UWCB (one-food diets, fasting, diet pill use, and purging). All statistical analyses were performed to reflect complex sampling weights.

RESULTS

More female than male adolescents reported to be engaged in any of the following UWCBs: one-food diets (female: 9.6%, male: 4.8%), fasting (female: 11.6%, male: 7.4%), diet pill use (female: 2.9%, male: 1.5%), and purging (female: 4.1%, male: 2.2%). The prevalence of all UWCBs tended to increase as energy drink intake (P < 0.001), cigarette smoking (P < 0.001), and electronic cigarette use (P < 0.001) increased.

CONCLUSIONS

Health professionals who work with adolescents need to be aware of the importance of screening for UWCB, including one-food diets, fasting, diet pill use, and purging, especially as a co-occurrence with substance use.

Bridging eating disorder symptoms and trait anxiety in patients with eating disorders: A network approach

OBJECTIVE

Anxiety is thought to influence the development and maintenance of eating disorders (EDs). However, little is known about how, specifically, anxiety influences ED symptoms and vice versa. Network analysis identifies how symptoms within and across disorders are interconnected. In a network, central nodes (i.e., symptoms) have the strongest relations to other nodes and are thought to maintain psychopathology. Bridge nodes are symptoms in one diagnostic cluster that are strongly connected to symptoms in another diagnostic cluster and are thought to explain comorbidity. We identified central and bridge nodes in a network of ED symptoms and trait anxiety features.

METHOD

We estimated a regularized partial correlation network in patients with mixed EDs (N = 296). ED symptoms were assessed with the Eating Disorder Examination-Questionnaire. Trait anxiety was assessed with the Trait subscale of the State-Trait Anxiety Inventory. Items to include in the network were selected with a statistical algorithm to ensure that all nodes represented unique constructs. Central and bridge nodes were identified with empirical calculations.

RESULTS

Central ED nodes were dietary restraint, as well as overvaluation of and dissatisfaction with shape and weight. The central trait anxiety node was low feelings of satisfaction. The strongest ED bridge node was avoidance of social eating. The strongest trait anxiety bridge node was low self-confidence.

DISCUSSION

Avoidance of social eating and low self-esteem may be routes through which EDs and trait anxiety are linked.

Examining a momentary mediation model of appearance-related stress, anxiety, and eating disorder behaviors in adult anorexia nervosa

PURPOSE

Appearance-related stress may result from appearance-focused events such as seeing one's reflection, seeing media images, and shopping for clothes. The purpose of this study was to examine the prospective association between momentary appearance-related stress and eating disorder (ED) behaviors (i.e., binge eating and vomiting) among women with anorexia nervosa (AN) using ecological momentary assessment (EMA). We hypothesized that appearance-related stress at Time 1 would predict binge eating and vomiting at Time 2, and that this prospective association would be mediated by momentary anxiety at Time 2 (controlling for anxiety at Time 1).

METHODS

Women with AN completed a 2-week EMA protocol involving repeated daily assessments of experiences and behaviors.

RESULTS

Momentary appearance-related stress preceded binge eating and vomiting, and momentary anxiety mediated the prospective association between appearance-related stress and ED behaviors.

CONCLUSIONS

Targeted momentary interventions delivered in the natural environment that address appearance-related stress may have utility in the treatment of ED behaviors.

Patterns of weight control behavior persisting beyond young adulthood: Results from a 15-year longitudinal study

OBJECTIVE

Dieting and unhealthy weight control behaviors have been associated with negative outcomes. Most research has examined the prevalence of these behaviors in adolescence and young adulthood. Less is known about whether they persist further into adulthood. We examined patterns of weight control behaviors beyond young adulthood using data from 1,455 males and females participating in Project EAT (Eating and Activity in Teens and Young Adults), a 15-year population-based, longitudinal study.

METHOD

Participants completed surveys assessing dieting, high-frequency dieting (i.e., 5+ times/year), unhealthy weight control (e.g., fasting), and extreme weight control (e.g., vomiting) at each 5-year assessment (Waves 1-4). Longitudinal logistic regression models tested trends in weight control behaviors across the waves. Likelihood of persisting or discontinuing each behavior from Wave 3 to Wave 4 was examined through cross tabulations.

RESULTS

Between Waves 3 and 4 in adulthood, dieting increased for both genders (Women: p < .001; Men: p = .004) and high-frequency dieting (p < .001) and unhealthy weight control behaviors (p = .011) increased for men. For both genders, dieting and unhealthy weight control patterns initiated in prior to young adulthood were more likely to persist than cease in adulthood (ps < .001).

DISCUSSION

Weight control behaviors continue to be prevalent in adulthood, and to especially increase among men. Research is needed to understand the consequences of weight control behaviors in different life stages; however, the results suggest that interventions to decrease unhealthy weight management practices may be needed well into adulthood.

Longitudinal associations between psychotic experiences and disordered eating behaviours in adolescence: a UK population-based study

BACKGROUND

Psychotic experiences might represent non-specific markers of poor mental health in adolescence. However, only a few predominantly cross-sectional studies have tested their association with disordered eating behaviours in adolescent and adult populations. The aim of this study was to explore the association between psychotic experiences at age 13 years, and disordered eating behaviours and body-mass index (BMI) at age 18 years.

METHODS

We used data from the Avon Longitudinal Study of Parents and Children, a longitudinal birth cohort based in Avon (England, UK) including mothers with an expected delivery date between April 1, 1991, and Dec 31, 1992, and their children. Psychotic experiences (such as delusions and hallucinations) and BMI were measured at clinical assessments when children were nearly aged 13 years, and data on disordered eating behaviours (ie, presence of binge eating, purging, fasting, or excessive exercise for weight loss; any of these behaviours [included to increase statistical power]; and number of behaviours [included to investigate severity]) were obtained via a postal questionnaire that used adapted questions from the Youth Risk Behaviour Surveillance System questionnaire at approximately age 18 years. For each outcome, we ran a univariable model and four multivariable models (logistic, linear [for BMI], or negative binomial [for the number of behaviours] regression), progressively adjusting for child and maternal sociodemographic, physical, and mental health characteristics (including child's sex, and maternal age, marital status, and highest academic qualification); autistic traits at age 7 years (measured with the Social and Communication Disorder Checklist); baseline BMI at age 13 years, and depressive symptoms at baseline (ie, at age 13 years when psychotic experiences were measured: childs' symptoms measured with the Moods and feelings Questionnaire, and maternal symptoms measured at 32 weeks' gestation with the Edinburgh Postnatal Depression Scale). We imputed missing outcome and covariate data.

FINDINGS

Our sample included 6361 children, of whom 734 (12%) reported psychotic experiences at age 13 years. In univariable models, psychotic experiences were associated with greater odds of reporting any disordered eating behaviours (odds ratio [OR] 1·92, 95% CI 1·46-2·52; p<0·0001), and more severe symptoms (as measured by the number of disordered eating behaviours: 0·58, 0·32-0·84; p<0·0001) at age 18 years. These associations were slightly attenuated by adjustment for maternal and child characteristics (any disordered eating behaviours OR 1·82, 95% CI 1·35-2·44, p<0·0001; number of disordered eating behaviours 0·49, 95% CI 0·23-0·75, p<0·00001), autistic traits at age 7 years (any disordered eating behaviours OR 1·80, 95% CI 1·34-2·41, p<0·0001; number of disordered eating behaviours 0·48, 95% CI 0·22-0·74, p<0·00001), and BMI (any disordered-eating behaviours OR 1·83, 95% CI 1·36-2·46, p<0·0001; number of disordered-eating behaviours 0·32, 95% CI 0·06-0·57, p<0·00001) Adjusting for baseline depressive symptoms attenuated, but not removed, these associations (any disordered eating OR 1·50, 95% CI 1·10-2·03, p=0·010; more severe symptoms 0·32, 0·06-0·57, p=0·017). Psychotic experiences were also associated with greater binge eating, purging, and fasting behaviours, although some associations weakened after controlling for depressive symptoms. We noted no associations between psychotic experiences and excessive exercise or BMI in any of the models.

INTERPRETATION

Our findings suggested that psychotic experiences are markers of increased risk for several disordered eating behaviours in late adolescence, possibly by indicating more severe psychopathology in early adolescence. More research investigating shared risk factors for psychotic experiences and eating disorders is warranted to elucidate shared and specific causal pathways.

FUNDING

Wellcome Trust, the Royal Society, University College London Hospitals National Institute for Health Research Biomedical Research Centre, UK Medical Research Council, and the University of Bristol.

Risk factors for disordered weight control behaviors among Korean adolescents: Multilevel analysis of the Korea Youth Risk Behavior Survey

OBJECTIVE

To investigate the prevalence and risk factors for disordered weight control behaviors (DWCB) in South Korean adolescents at multiple levels, including individual, family, school, and geographic area.

METHOD

We drew participants from the 11th Korea Youth Risk Behavior Web-based Survey, conducted in 2015, with 65,529 adolescents (31,687 girls, 33,842 boys) aged 12-18 years. DWCB was defined as engaging in any of the following behaviors for weight control over the past month: fasting, one-food diet (eating only one food over an extended period of time for weight control), vomiting, and taking laxatives/diuretics/unprescribed diet pills. Sex-stratified four-level multilevel logistic models examined potential predictors of DWCB, including age, body-mass index, puberty, perceived household economic status, parental education, living structure, school type and sex-composition, percentage of students participating in school nutrition programs, and urbanicity.

RESULTS

Overall, 6.2% of Korean adolescents (8.9% of girls, 3.7% of boys) exhibited any DWCB. We found significant between-school variation among girls and boys and between-classroom variation among girls. Older age, overweight/obesity, pubertal maturity, high household economic status (vs. mid-range economic status), and vocational schooling (vs. general) were positively associated with DWCB among girls and boys. Low household economic status (vs. mid-range economic status), higher parental education, and coeducational schooling (vs. single-sex) were positively associated with DWCB among girls only.

DISCUSSION

The findings suggest that DWCB are prevalent among Korean adolescents across age, sex, and socioeconomic status. Social contextual factors including school and familial environmental factors, as well as individual characteristics, should be considered when developing effective prevention strategies.

Testing for interactive and non-linear effects of risk factors for binge eating and purging eating disorders

Almost no research has tested whether risk factors interact in the prediction of future eating disorder onset, which might suggest qualitatively distinct etiologic pathways. Accordingly, this prospective study tested for possible interactions between risk factors in the prediction of binge eating and purging eating disorders in adolescents. It also examined sex differences in pathways to risk. Two analytical approaches were used: (1) classification tree analysis (CTA), which is ideally suited to identifying non-linear interactions and the optimal cut-points for defining risk, with follow-up random forest analyses; and (2) two-way interaction terms in a series of logistic regression models. Data were drawn from the Western Australian Pregnancy Cohort (Raine) Study, a population-based study that followed participants from pre-birth to young adulthood. This study involved 1297 adolescents (49% male), 146 (11%) of whom developed bulimia nervosa, binge eating disorder or purging disorder in late adolescence. In CTA, sex was the first and most potent predictor of eating disorder risk with females showing a 5-fold increase in risk relative to males. For males and females, weight and eating concerns were the next most potent predictor of risk and three risk groups emerged, reflecting non-linear risk. For females with intermediate weight and eating concerns, externalizing problems emerged as an additional predictor. Interaction terms in logistic regression models did not produce significant results after correcting for multiple testing. Findings advance knowledge on risk pathways to eating disorder onset, highlight non-linear risk processes, and provide cut-points for prospectively identifying high-risk youth for prevention programs.

Gender Conformity and Use of Laxatives and Muscle-Building Products in Adolescents and Young Adults

BACKGROUND

Use of laxatives for weight loss and drugs or supplements to build muscle (eg, steroids) differs by gender and sexual orientation; little is known about factors contributing to these disparities. Conformity to gender norms concerning appearance could underlie these differences.

METHODS

This study examined associations between childhood gender conformity and laxative and muscle-building product use from ages 13 to 25 years in a sample of 13 683 males and females in the US prospective Growing Up Today Study. Adjusted multivariable logistic regression models of repeated measures estimated odds of past-year laxative and muscle-building product use by quartiles of greater childhood gender conformity in heterosexual and sexual minority (eg, bisexual, gay) participants.

RESULTS

By age 23 years, ∼20% of sexual minority females reported past-year laxative use. By age 19 years, 12% of all males reported past-year muscle-building product use. Sexual minority females had twice the odds of heterosexual females of using laxatives (P < .0001). The most gender-conforming females had 50% greater odds than the least-conforming females of using laxatives (P < .01). Moderate (odds ratio, 2.09; 95% confidence interval, 1.58-2.75) and highly (odds ratio, 1.79; 95% confidence interval, 1.38-2.33) gender-conforming males had higher odds than gender-nonconforming males of using muscle-building products.

CONCLUSIONS

Sexual minority females are at high risk for laxative abuse. Regardless of sexual orientation, gender conformity increased the odds of laxative abuse among females and muscle-building product use among males. Findings can inform prevention efforts to target youth at risk for laxative or muscle-building product use.

Eating disorders in a multi-ethnic inner-city UK sample: prevalence, comorbidity and service use

PURPOSE

No studies have investigated the prevalence of eating disorders (ED) according to DSM-5 criteria and few have explored their comorbidity and service use in the general population in the UK. We aimed to estimate the prevalence, comorbidity, and service use in individuals with ED in a multi-ethnic inner city sample.

METHODS

A total of 1698 individuals (age 16/90) were screened for ED in the first phase of the South East London Community Health Study and 145 were followed up with a diagnostic interview. Data was weighed for survey design and Chi Square tests were used to investigate socio-demographic distribution, comorbidity and service use in participants with ED.

RESULTS

The point prevalence of ED was 4.4 % (Binge Eating Disorder (BED) 3.6 %; Bulimia Nervosa (BN) 0.8 %) and 7.4 % when including sub-threshold diagnoses (Purging Disorder (PD) 0.6 %; Other Specified Feeding and Eating Disorders (OSFED) 2.4 %). No cases of AN were identified. Purging Disorder was the ED with the highest proportion of comorbid disorders. A minority of participants with ED had accessed specialist care services.

CONCLUSIONS

ED are common, the comorbidity of ED was in line with previous studies and no ethnic differences were identified. Although PD is not a full diagnosis in DSM-5, we found some evidence of high comorbidity with other disorders, that needs to be replicated using larger samples. Service use was low across ED diagnoses, despite high levels of comorbidity.

Empirically derived subtypes of full and subthreshold anorexia nervosa in adolescent females: understanding general psychopathology and treatment implications

The aim of this study was to derive clinically relevant subtypes of anorexia nervosa (AN) and subthreshold AN using general psychopathology variables and to determine how they differ on eating pathology. Participants were 39 adolescent females aged 13 to 18 years, diagnosed with AN or subthreshold AN. Cluster analysis revealed two subtypes that differed significantly in eating pathology. Cluster 1 patients were typically underweight with no clinical elevations on eating or psychopathology measures. Cluster 2 patients were mostly of healthy weight with greater eating and psychological problems. Findings allow clinicians to classify and understand AN beyond diagnostic criteria, and implement interventions that consider presentation beyond eating pathology.