Genetic factors contribute to anorexia nervosa (AN); and the first genome-wide significant locus has been identified. We describe methods and procedures for the Anorexia Nervosa Genetics Initiative (ANGI), an international collaboration designed to rapidly recruit 13,000 individuals with AN and ancestrally matched controls. We present sample characteristics and the utility of an online eating disorder diagnostic questionnaire suitable for large-scale genetic and population research. ANGI recruited from the United States (US), Australia/New Zealand (ANZ), Sweden (SE), and Denmark (DK). Recruitment was via national registers (SE, DK); treatment centers (US, ANZ, SE, DK); and social and traditional media (US, ANZ, SE). All cases had a lifetime AN diagnosis based on DSM-IV or ICD-10 criteria (excluding amenorrhea). Recruited controls had no lifetime history of disordered eating behaviors. To assess the positive and negative predictive validity of the online eating disorder questionnaire (ED100K-v1), 109 women also completed the Structured Clinical Interview for DSM-IV (SCID), Module H. Blood samples and clinical information were collected from 13,363 individuals with lifetime AN and from controls. Online diagnostic phenotyping was effective and efficient; the validity of the questionnaire was acceptable. Our multi-pronged recruitment approach was highly effective for rapid recruitment and can be used as a model for efforts by other groups. High online presence of individuals with AN rendered the Internet/social media a remarkably effective recruitment tool in some countries. ANGI has substantially augmented Psychiatric Genomics Consortium AN sample collection. ANGI is a registered clinical trial: clinicaltrials.govNCT01916538; https://clinicaltrials.gov/ct2/show/NCT01916538?cond=Anorexia+Nervosa&draw=1&rank=3.

Background: The Eating Disorders Genetics Initiative (EDGI) is an international investigation exploring the role of genes and environment in anorexia nervosa, bulimia nervosa, and binge-eating disorder.Methods: A total of 14,500 individuals with eating disorders and 1500 controls will be included from the United States (US), Australia (AU), New Zealand (NZ), and Denmark (DK). In the US, AU, and NZ, participants will complete comprehensive online phenotyping and will submit a saliva sample for genotyping. In DK, individuals with eating disorders will be identified by the National Patient Register, and genotyping will occur using bloodspots archived from birth. A genome-wide association study will be conducted within EDGI and via meta-analysis with other data from the Eating Disorders Working Group of the Psychiatric Genomics Consortium (PGC-ED).Discussion: EDGI represents the largest genetic study of eating disorders ever to be conducted and is designed to rapidly advance the study of the genetics of the three major eating disorders (anorexia nervosa, bulimia nervosa, and binge-eating disorder). We will explicate the genetic architecture of eating disorders relative to each other and to other psychiatric and metabolic disorders and traits. Our goal is for EDGI to deliver “actionable” findings that can be transformed into clinically meaningful insights.Trial registration: EDGI is a registered clinical trial: clinicaltrials.govNCT04378101.

Objective: We describe the prevalence and sociodemographic factors associated with screen‐detected disordered eating and related traits in a population‐based sample of women in China. We also explored prevalence trends over time.Method: A total of 4,218 females aged 12–50 were sampled from 15 provinces as part of the China Health and Nutrition Survey (CHNS) in 2015. The SCOFF questionnaire screened for disordered eating and the selected questions from the Eating Disorders Examination‐Questionnaire measured dietary restraint, shape concerns, and weight concerns. Body mass index (BMI) was measured and sociodemographic factors captured urban/rural residence, age, ethnicity, income, education, marital status, and occupational status. We calculated the prevalence of screen‐detected disordered eating and related traits broadly and across several dimensions and compared prevalence estimates to 2009 and 2011 reports.Results: We detected 296 individuals who screened positive for disordered eating on the SCOFF (prevalence = 7.04%). Positive screens were associated with urban residence (p = .002) and higher education levels (p < .001). Scores on restraint, shape concerns, and weight concerns were all higher for individuals in urban versus village locations (all p's < .001), and with higher BMI (p < .001) for shape and weight concerns. The prevalence of screen‐detected disordered eating increased numerically across 2009, 2011, and 2015.Discussion: The prevalence of screen‐detected disordered eating in mainland China was comparable to other populations worldwide obtained from a recent meta‐analysis. The distribution of disordered eating and related traits varied by several sociodemographic factors, which include age, BMI, urban/rural residence, education, and income, suggesting important directions for case detection and intervention in China.

Background: Among the most disabling and fatal psychiatric illnesses, eating disorders (EDs) often manifest early in life, which encourages investigations into in utero and perinatal environmental risk factors. The objective of this study was to determine whether complications during pregnancy and birth and perinatal conditions are associated with later eating disorder risk in offspring and whether these associations are unique to EDs.Methods: All individuals born in Denmark to Danish-born parents 1989–2010 were included in the study and followed from their 6^th birthday until the end of 2016. Exposure to factors related to pregnancy, birth, and perinatal conditions was determined using national registers, as were hospital-based diagnoses of anorexia nervosa (AN), bulimia nervosa, and eating disorder not otherwise specified during follow-up. For comparison, diagnoses of depressive, anxiety, and obsessive-compulsive disorders were also included. Cox regression was used to compare hazards of psychiatric disorders in exposed and unexposed individuals.Results: 1 167 043 individuals were included in the analysis. We found that similar to the comparison disorders, prematurity was associated with increased eating disorder risk. Conversely, patterns of increasing risks of EDs, especially in AN, with increasing parental ages differed from the more U-shaped patterns observed for depressive and anxiety disorders.Conclusions: Our results suggest that pregnancy and early life are vulnerable developmental periods when exposures may influence offspring mental health, including eating disorder risk, later in life. The results suggest that some events pose more global transdiagnostic risk whereas other patterns, such as increasing parental ages, appear more specific to EDs.

Objective: China is undergoing dramatic Westernization, hence may be able to provide unique insights into the role of sociocultural factors in disease. The purpose of this exploratory study was two‐fold: to describe the prevalence of screening‐detected eating disorders and disordered eating in China at the first occasion of assessment in the large‐scale China Health and Nutrition Survey (CHNS) and to explore the associations between dietary practices and disordered eating. Regarding the first objective, participants are provincially representative and in subsequent waves will be followed longitudinally.Method: CHNS participants were recruited using multistage, cluster random sampling, beginning in 1989. In this study, participants comprised 259 female adolescents (12–17 years) and 979 women (18–35 years) who participated in the CHNS 2009 survey, which is the first CHNS survey to assess disordered eating. Dietary practice‐disordered eating associations were investigated with logistic regression adjusting for age, body mass index, and urbanization.Results: Of the participants, 6.3% (95% CI: 4.8, 8.2) of adults and 7.8% (95% CI: 5.0, 12.0) of adolescents had a screening‐detected eating disorder. Dietary practices had non‐significant associations with disordered eating at the general population level, except for protein consumption among women. There was evidence that skipping meals and a high‐fat diet may confer risk.Discussion: Screening‐detected eating disorders in China are lower in prevalence than in developed countries. Dietary practices had fairly limited associations with disordered eating at the general population level; protein consumption, skipping meals, and a high‐fat diet are candidate dietary practice exposures for disordered eating. Copyright © 2014 John Wiley & Sons, Ltd and Eating Disorders Association.

Background: Anorexia nervosa (AN) is a psychiatric disorder with complex etiology, with a significant portion of disease risk imparted by genetics. Traditional genome-wide association studies (GWAS) produce principal evidence for the association of genetic variants with disease. Transcriptomic imputation (TI) allows for the translation of those variants into regulatory mechanisms, which can then be used to assess the functional outcome of genetically regulated gene expression (GReX) in a broader setting through the use of phenome-wide association studies (pheWASs) in large and diverse clinical biobank populations with electronic health record phenotypes.Methods: Here, we applied TI using S-PrediXcan to translate the most recent PGC-ED AN GWAS findings into AN-GReX. For significant genes, we imputed AN-GReX in the Mount Sinai BioMe™ Biobank and performed pheWASs on over 2000 outcomes to test the clinical consequences of aberrant expression of these genes. We performed a secondary analysis to assess the impact of body mass index (BMI) and sex on AN-GReX clinical associations.Results: Our S-PrediXcan analysis identified 53 genes associated with AN, including what is, to our knowledge, the first-genetic association of AN with the major histocompatibility complex. AN-GReX was associated with autoimmune, metabolic, and gastrointestinal diagnoses in our biobank cohort, as well as measures of cholesterol, medications, substance use, and pain. Additionally, our analyses showed moderation of AN-GReX associations with measures of cholesterol and substance use by BMI, and moderation of AN-GReX associations with celiac disease by sex.Conclusions: Our BMI-stratified results provide potential avenues of functional mechanism for AN-genes to investigate further.