Late onset eating disorders in Spain: clinical characteristics and therapeutic implications

Non-suicidal self-injury among individuals with an eating disorder: A systematic review and prevalence meta-analysis

OBJECTIVE

This study aimed to quantify the prevalence of non-suicidal self-injury across eating disorders (EDs) and within diagnostic categories through systematic review and proportional, or so-called prevalence, meta-analysis.

METHOD

Included studies had to contain individuals with a verified diagnosis of an ED. The last literature search was conducted on September 11, 2023, for studies published on or before September 2023 without a restriction on earliest publication year. Results were synthesized and analyzed using the "metaprop" package in R and presented using forest plots. Bias was assessed by a Peters' regression test and funnel plot.

RESULTS

79 studies published between 1985 and 2023 were included encompassing 32,334 individuals with an ED. Importantly, 42 studies were not included in any other meta-analyses on self-injury in EDs to date. Overall prevalence of non-suicidal self-injury was 34.59% (95%CI = 30.49-38.81). Prevalence in anorexia nervosa restrictive type, binge/purge type, bulimia nervosa, binge eating disorder and other specified feeding/eating disorder were 23.19% (95%CI = 16.96-30.03%), 41.98% (95%CI = 32.35-51.91%), 36.97% (95%CI = 30.69-43.46%), 21.21% (95%CI = 14.93-28.12%) and 37.65% (95%CI = 28.59-47.09%), respectively. Prevalence estimations could not be estimated for other ED categories due to lack of a sufficient number of studies.

DISCUSSION

Non-suicidal self-injury is prevalent across both binge/purge and restrictive EDs. Considering the transdiagnostic nature of self-injurious behaviors in ED, the results highlight the importance of assessment and monitoring of self-injury in people with ED, irrespective of specific diagnoses. The method of determining self-injury varied across studies and may limit this study.

PUBLIC SIGNIFICANCE

This study highlights the prevalence of self-injury across eating disorders irrespective of diagnosis and within specific EDs. While diagnoses known to exhibit self-injurious behaviors (e.g., bulimia nervosa, anorexia nervosa binge/purge subtype) demonstrated the highest prevalence of self-injury, all diagnoses were found to have a prevalence greater than 20%. These findings suggest the importance of assessing and monitoring all individuals with an eating disorder for the presence of self-injury.

Epidemiology of eating disorders: population, prevalence, disease burden and quality of life informing public policy in Australia-a rapid review

BACKGROUND

Understanding of the epidemiology and health burden of eating disorders has progressed significantly in the last 2 decades. It was considered one of seven key areas to inform the Australian Government commissioned National Eating Disorder Research and Translation Strategy 2021-2031, as emerging research had highlighted a rise in eating disorder prevalence and worsening burden-of-illness. The aim of this review was to better understand the global epidemiology and impact of eating disorders to inform policy decision-making.

METHODS

Using a systematic Rapid Review methodology, ScienceDirect, PubMed and Medline (Ovid) were searched for peer-reviewed studies published between 2009 and 2021. Clear inclusion criteria were developed in consultation with experts in the field. Purposive sampling of literature was conducted, which predominately focused on higher-level evidence (meta-analyses, systematic reviews, and large epidemiological studies), synthesised, and narratively analysed.

RESULTS

135 studies were deemed eligible for inclusion in this review (N = 1324). Prevalence estimates varied. Global Lifetime prevalence of any eating disorder ranged from 0.74 to 2.2% in males, and 2.58-8.4% in females. Australian 3-month point-prevalence of broadly defined disorders was around 16% in females. Eating disorders appeared more prevalent in young people and adolescents, particularly females (in Australia: eating disorders ~ 22.2%; disordered eating ~ 25.7%). Limited evidence was found on sex, sexuality and gender diverse (LGBTQI +) individuals, particularly males, who had a six-fold increase in prevalence compared to the general male population, with increased illness impact. Similarly, limited evidence on First Australian's (Aboriginal and Torres Strait Islander) suggests prevalence rates similar to non-Indigenous Australians. No prevalence studies were identified specifically assessing culturally and linguistically diverse populations. Global disease burden of any eating disorder was 43.4 age-standardised disability-adjusted-life-years per 100,000; increasing by 9.4% between 2007 and 2017. Australian's total economic cost was estimated at $84 billion from years-of-life lost due to disability and death, and annual lost earnings ~ $1.646 billion."

CONCLUSIONS

There is no doubt that eating disorder prevalence and impact are on the rise, particularly in at-risk and understudied populations. Much of the evidence came from female-only samples, and Western, high-income countries which more readily have access to specialised services. Future research should examine more representative samples. There is an urgent need for more refined epidemiological methods to better understand these complex illnesses over time, to guide health policy and development-of-care.

Network-based validation of the psychometric questionnaire EDI-3 for the assessment of eating disorders

Assessing the validity of a psychometric test is fundamental to ensure a reliable interpretation of its outcomes. Few attempts have been made recently to complement classical approaches (e.g., factor models) with a novel technique based on network analysis. The objective of the current study is to carry out a network-based validation of the Eating Disorder Inventory 3 (EDI-3), a questionnaire designed for the assessment of eating disorders. Exploiting a reliable, open source sample of 1206 patients diagnosed with an eating disorder, we set up a robust validation process encompassing detection and handling of redundant EDI-3 items, estimation of the cross-sample psychometric network, resampling bootstrap procedure and computation of the median network of the replica samples. We then employed a community detection algorithm to identify the topological clusters, evaluated their coherence with the EDI-3 subscales and replicated the full validation analysis on the subpopulations corresponding to patients diagnosed with either anorexia nervosa or bulimia nervosa. Results of the network-based analysis, and particularly the topological community structures, provided support for almost all the composite scores of the EDI-3 and for 2 single subscales: Bulimia and Maturity Fear. A moderate instability of some dimensions led to the identification of a few multidimensional items that should be better located in the intersection of multiple psychological scales. We also found that, besides symptoms typically attributed to eating disorders, such as drive for thinness, also non-specific symptoms like low self-esteem and interoceptive deficits play a central role in both the cross-sample and the diagnosis-specific networks. Our work adds insights into the complex and multidimensional structure of EDI-3 by providing support to its network-based validity on both mixed and diagnosis-specific samples. Moreover, we replicated previous results that reinforce the transdiagnostic theory of eating disorders.

Temporally ordered associations between type 2 diabetes and brain disorders - a Danish register-based cohort study

BACKGROUND

Type 2 diabetes mellitus (T2DM) is linked with several neurodegenerative and psychiatric disorders, either as a comorbid condition or as a risk factor. We aimed to expand the evidence by examining associations with a broad range of brain disorders (psychiatric and neurological disorders, excluding late-onset neurodegenerative disorders), while also accounting for the temporal order of T2DM and these brain disorders.

METHODS

In a population-based cohort-study of 1,883,198 Danish citizens, born 1955-1984 and followed until end of 2016, we estimated associations between T2DM and 16 brain disorders first diagnosed between childhood and mid-adulthood. We calculated odds ratios (OR) and hazard ratios (HR) with 95% confidence intervals (CI) in temporally ordered analyses (brain disorder diagnosis after T2DM and vice versa), adjusted for sex, age, follow-up, birth year, and parental factors.

RESULTS

A total of 67,660 (3.6%) of the study population were identified as T2DM cases after age 30 and by a mean age of 45 years (SD of 8 years). T2DM was associated with most psychiatric disorders. Strongest associations were seen with other (i.e. non-anorectic) eating disorders (OR [95% CI]: 2.64 [2.36-2.94]) and schizophrenia spectrum disorder (2.73 [2.63-2.84]). Among neurological disorders especially inflammatory brain diseases (1.73 [1.57-1.91]) and epilepsy (1.67 [1.60-1.75]) were associated with T2DM. Most associations remained in both directions in the temporally ordered analyses. For most psychiatric disorders, associations were strongest in females.

CONCLUSIONS

T2DM was associated with several psychiatric and neurological disorders, and most associations were consistently found for both temporal order of disorders. This suggests a shared etiology of T2DM and those brain disorders. This study can form the starting point for studies directed at further elucidating potential causal links between disorders and shared biological mechanisms.

A comparison of eating disorder symptomatology, psychological distress and psychosocial function between early, typical and later onset anorexia nervosa

OBJECTIVE

Epidemiological studies suggest that the incidence of anorexia nervosa (AN) is increasing in younger populations, with some evidence that clinical differences occur according to age of onset (AOO), which may impact prognostic outcomes. The current study sought to compare eating disorder (ED) symptomatology, psychological distress and psychosocial function between early onset (EO), typical onset (TO) and later onset (LO) AN in a large sample of treatment-seeking patients with a diagnosis of AN.

METHODS

Participants included 249 individuals with a diagnosis of AN who were assessed at an outpatient ED service. The sample was divided into three groups based on AOO; those with an AOO ≤14 years (N = 58) were termed 'EO-AN', those with an AOO between 15 and 18 years (N = 113) were termed 'TO-AN' and those with an AOO of > 18 years (N = 78) were termed 'LO-AN'. Comparisons were made between AOO groups on assessments of ED symptomatology, psychological distress and psychosocial function.

RESULTS

EO-AN patients reported a significantly longer illness duration than both TO-AN and LO-AN groups. After controlling for effect of illness duration, the EO-AN group demonstrated significantly higher ED symptomatology and dysmorphic concern compared to the LO-AN group. The EO-AN group demonstrated significantly decreased cognitive flexibility compared to both the TO-AN and LO-AN groups.

DISCUSSION

These findings suggest that clinical differences do occur according to AOO in AN whereby EO-AN may represent a more severe form of illness that is not attributable to increased illness duration. Treatment strategies which specifically address patients with EO-AN may improve long term health outcomes and recovery.

Extremely severe anorexia nervosa: Hospital course of 354 adult patients in a clinical nutrition-eating disorders-unit

BACKGROUND AND AIMS

The clinical nutrition-eating disorders-unit in Raymond Poincaré Hospital is a reference center for the management of severe malnutrition and its complications in patients with anorexia nervosa (AN). The purpose of this study is to specify socio-demographic, anamnesic and clinical characteristics of AN patients hospitalized for extreme malnutrition, to identify types and prevalence of medical complications presented during their hospitalization for refeeding and the evolution of patients nutritional status.

METHODS

Demographic, clinical and paraclinical data of 354 severely malnourished AN patients were collected, during their first hospitalization in the unit, between November 1997 and January 2014, through medical records. The prevalence of medical complications was compared between the 2 AN subtypes (restricting and binging-purging).

RESULTS

339 patients were female and mean age was 28.7 ± 10.7 years old. Duration of AN was 9.5 ± 9 years, 173 (48.9%) patients had a restricting AN subtype. BMI at admission was 12.2 ± 1.6 kg/m², 280 (79.3%) patients had already been hospitalized for AN in other hospitals before. Psychiatric comorbidities were present in 168 (47.5%) patients. Associated somatic comorbidities concerned 70 (19.8%) patients. Outcomes during hospitalization were marked by 4.1 ± 3.9 kg weight gain on 36.9 ± 30.5 days. Enteral nutrition was provided in 304 (85.9%) patients. Main medical complications during hospitalization were: anemia (79%), neutropenia (53.9%), hypertransaminasemia (53.7%), osteoporosis (46.3%), hypokalemia (39.5%), hypophosphatemia (26%), hypoglycemia (13.8%), infectious complications (24.3%), cardiac dysfunction (7.1%), and proven gelatinous bone marrow transformation (6.5%). Hypokalemia was more frequent in binging-purging subtype. Lympho-neutropenia and hypertransaminasemia were more frequent in restricting subtype. During their hospitalization, 35 (10%) patients were referred to medical intensive care unit and 5 patients died.

CONCLUSIONS

AN patients hospitalized for severe malnutrition in a specialized clinical nutrition unit have severe and frequent medical complications. Psychiatric comorbidities are also frequent and could complicate medical care. A specialized and multidisciplinary management of these patients is therefore essential.

Does Age Impact the Clinical Presentation of Adult Women Seeking Specialty Eating Disorder Treatment?

Recent evidence suggests that eating disorders (EDs) are becoming increasingly common in older women. Previous research examining differences between younger and older women with EDs has been mixed, making it unclear whether older women with EDs represent a distinct group. We sought to determine whether there are age differences in the clinical presentation of women seeking specialty treatment for an ED. We examined the linear relationship between age and clinical constructs among adult women (N = 436) diagnosed with a Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, ED. Across analyses, there was no impact of age on most measures of ED symptoms, comorbid psychopathology, self-esteem, quality of life, and motivation to change. However, older age was associated with fewer interoceptive awareness difficulties, maturity fears, anxiety symptoms, and body image concerns. These findings suggest that the clinical presentation of older ED cases is largely similar, although somewhat less severe than in younger women. The implications of this research for future research and treatment are discussed.

Validation of the Caregiver Skills (CASK) scale in Catalonia: Concordance between caregivers in attitudes and behaviours

OBJECTIVE

The aim of this study was to validate a Spanish version of the Caregiver Skills scale (CASK) in a sample of eating disorder (ED) caregivers. A further aim was to examine the concordance/discrepancy between them (namely, between the mothers and fathers of ED patients).

METHOD

Two hundred sixty-five ED caregivers were recruited from ED centers in Catalonia, Spain. Confirmatory factor analyses was used to test the factorial structure of the CASK scale. Cronbach's α was used to measure internal consistency of the CASK scales. A comparison of the CASK measures between respondents (mothers and fathers) was conducted using generalized estimating equations.

RESULTS

Confirmatory factor analysis of the Spanish version of the CASK corroborated the strong factorial validity of the 6 factors of the original CASK questionnaire. Mothers and fathers did not differ significantly on CASK overall and subscale scores. There was however less concordance between parents on the bigger picture (ICC = 0.28) and biting your tongue (ICC = 0.08) subscales.

CONCLUSIONS

The CASK is a valid tool to assess ED-related attitudes in Spanish-speaking caregivers. Furthermore, caregivers and patients alike could stand to benefit from interventions focused on improving areas such as ED beliefs, effective communication, quality of life, and emotional distancing.

Self and other body perception in anorexia nervosa: The role of posterior DMN nodes

OBJECTIVES

Body image distortion is a core symptom of anorexia nervosa (AN), which involves alterations in self- (and other's) evaluative processes arising during body perception. At a neural level, self-related information is thought to rely on areas of the so-called default mode network (DMN), which, additionally, shows prominent synchronised activity at rest.

METHODS

Twenty female patients with AN and 20 matched healthy controls were scanned using magnetic resonance imaging when: (a) viewing video clips of their own body and another's body; (b) at rest. Between-group differences within the DMN during task performance were evaluated and further explored for task-related and resting-state-related functional connectivity alterations.

RESULTS

AN patients showed a hyperactivation of the dorsal posterior cingulate cortex during their own-body processing but a response failure to another's body processing at the precuneus and ventral PCC. Increased task-related connectivity was found between dPCC-dorsal anterior cingulate cortex and precuneus-mid-temporal cortex. Further, AN patients showed decreased resting-state connectivity between the dPCC and the angular gyrus.

CONCLUSIONS

The PCC and the precuneus are suggested as key components of a network supporting self-other-evaluative processes implicated in body distortion, while the existence of DMN alterations at rest might reflect a sustained, task-independent breakdown within this network in AN.

Does Late-onset Anorexia Nervosa Exist? Findings From a Comparative Study in Singapore

OBJECTIVE

The incidence of cases of older onset anorexia nervosa (AN) has increased in recent years. However, the literature on late-onset AN has been inconclusive. The goal of this study was to compare late-onset with early-onset cases of AN.

METHODS

Cases of AN presenting to an eating disorders treatment service were identified and the associated medical records were studied retrospectively.

RESULTS

Of the 577 cases of AN that were studied, 7.1% were late-onset. Unlike the early-onset cases of AN, the late-onset cases reported less teasing and more relationship problems as a trigger for the illness. They were also less likely to join the eating disorders treatment program. Otherwise, the late-onset AN cases were largely similar to the early-onset cases.

CONCLUSIONS

Although differences exist between early-onset and late-onset cases of AN, these are few. Until stronger evidence emerges over time, there currently seems to be minimal justification to accord late-onset AN a unique position in psychiatric nosology.

Eating pathology in midlife women: Similar or different to younger counterparts?

OBJECTIVE

This study examined potential similarities and differences between women with eating disorders (EDs) in midlife and their younger counterparts.

METHOD

Seven hundred and three women assessed by a specialist eating disorder service were divided into three groups based on age (18-25, 25-40, and 40+) and compared on a number of clinical and demographic measures. Distribution of ED diagnoses was also examined between groups.

RESULTS

Midlife women were less likely to receive a diagnosis of anorexia nervosa and more likely to receive a diagnosis of binge-eating disorder than their younger counterparts. Duration of illness was longer and age of ED onset later in the midlife group but no differences were seen on measures of global ED pathology, psychosocial impairment, or psychological distress.

DISCUSSION

This study adds to the developing literature concerning EDs in midlife women, although further work is needed to support the findings presented here and to examine profiles of males presenting to treatment centers.

The Science Behind the Academy for Eating Disorders' Nine Truths About Eating Disorders

OBJECTIVE

In 2015, the Academy for Eating Disorders collaborated with international patient, advocacy, and parent organizations to craft the 'Nine Truths About Eating Disorders'. This document has been translated into over 30 languages and has been distributed globally to replace outdated and erroneous stereotypes about eating disorders with factual information. In this paper, we review the state of the science supporting the 'Nine Truths'.

METHODS

The literature supporting each of the 'Nine Truths' was reviewed, summarized and richly annotated.

RESULTS

Most of the 'Nine Truths' arise from well-established foundations in the scientific literature. Additional evidence is required to further substantiate some of the assertions in the document. Future investigations are needed in all areas to deepen our understanding of eating disorders, their causes and their treatments.

CONCLUSIONS

The 'Nine Truths About Eating Disorders' is a guiding document to accelerate global dissemination of accurate and evidence-informed information about eating disorders. Copyright © 2017 John Wiley & Sons, Ltd and Eating Disorders Association.

Lifetime prevalence of non-suicidal self-injury in patients with eating disorders: a systematic review and meta-analysis

BACKGROUND

Against a backdrop of increasing research, clinical and taxonomic attention in non-suicidal self-injury (NSSI), evidence suggests a link between NSSI and eating disorders (ED). The frequency estimates of NSSI in ED vary widely. Little is known about the sources of this variation, and no meta-analysis has quantified the association between ED and NSSI.

METHOD

Using random-effects meta-analyses, meta-regression analyses, and 1816-6466 unique participants with various ED, we estimated the weighted average percentage of individuals with ED, those with anorexia nervosa (AN) and those with bulimia nervosa (BN) who are reported to have a lifetime history of NSSI across studies. We further examined predictors of NSSI in ED.

RESULTS

The weighted average percentage of patients with a lifetime history of NSSI was 27.3% [95% confidence interval (CI) 23.8-31.0%] for ED, 21.8% (95% CI 18.5-25.6%) for AN, and 32.7% (95% CI 26.9-39.1%) for BN. The difference between BN and AN was statistically significant [odds ratio (OR) 1.77, 95% CI 1.14-2.77, p = 0.013]. The odds of NSSI increased by 24% for every 10% increase in the percentage of participants with histories of suicide attempts (OR 1.24, 95% CI 1.04-1.48, p = 0.020) and decreased by 26% for every 10% increase in the percentage of participants with histories of substance abuse (OR 0.74, 95% CI 0.58-0.95, p = 0.023).

CONCLUSIONS

In the specific context of ED, NSSI is highly prevalent and correlates positively with attempted suicide, urging for NSSI-focused treatments. A novel finding is that NSSI is potentially antagonized by substance abuse.

Medical outcomes for adults hospitalized with severe anorexia nervosa: An analysis by age group

OBJECTIVE

Relatively little has been written about the outcomes of medical stabilization, analyzed specifically across the age spectrum, in adults with severe anorexia nervosa (AN).

METHOD

We retrospectively evaluated clinical parameters relevant to acuity of illness and outcomes of early refeeding in 142 adults with severe AN, admitted for definitive inpatient medical stabilization from October 1, 2008 to December 31, 2012. Patients were categorized into three age groups: 17 to 29, 30 to 40, and 41+ years.

RESULTS

The study included 142 patients with median age of 28 years old (range 17-65 years). Fifty-four percent (n = 78) were under 30 years old, 23% (n = 32) between 30 and 40 years old, and 23% (n = 32) were over 40 years old. Average admission BMI did not differ among age groups, ranging from 12.7 to 13.2 kg/m(2). Of the admission parameters, only low serum albumin levels (more prevalent in older patients), high international normalized ratio (INR) levels (more prevalent in younger patients), and neutropenia (more prevalent in the <30 age group) varied with age. During hospitalization, rates of bradycardia, hypoglycemia, liver dysfunction, very low %IBW, refeeding hypophosphatemia, refeeding edema, length of stay, and discharge BMI did not differ with age. Age group was associated with rate of weekly weight gain only in patients with AN-binge purge subtype.

DISCUSSION

Results demonstrate medical abnormalities and response to medical stabilization in severely ill AN patients during hospitalization were mostly similar across the age span. This information should allay fears that the effect of age will make medical stabilization more difficult.

Eating disorders in midlife women: A perimenopausal eating disorder?

Eating disorders afflict women across the lifespan with peak onset during critical or sensitive developmental periods of reproductive hormone change, such as puberty. A growing body of research supports the role of reproductive hormones, specifically estrogen, in the risk for eating disorders and related symptomatology in adolescence and young adulthood. Like puberty, perimenopause is characterized by estrogen change and may also present a window of vulnerability to eating disorder development. Here, we discuss the evidence that suggests perimenopause indeed may be a vulnerable period for the development or redevelopment of an eating disorder for midlife women. Drawing from what is known about the influence of estrogen on eating disorders at younger ages and from other psychiatric disorders with similar risk trajectories (i.e., perimenopausal depression), we describe a potential mechanism of risk for a perimenopausal eating disorder and how this can be explored in future research. Investigating vulnerability to perimenopausal eating disorders will clarify eating disorder etiology, identify reproductive stage-specific risk profiles, and guide future treatment directions.

Eating Disorders in Late-life

Eating disorders are a heterogeneous group of complex psychiatric disorders characterized by abnormal eating behaviours that lead to a high rate of morbidity, or even death, if underestimated and untreated. The main disorders enlisted in the chapter of the Diagnostic and Statistic Manual of Mental Disorders-5 dedicated to "Feeding and Eating Disorders" are: anorexia nervosa, bulimia nervosa and binge eating disorder. Even though these abnormal behaviours are mostly diagnosed during childhood, interesting cases of late-life eating disorders have been reported in literature. In this review, these eating disorders are discussed, with particular attention to the diagnosis and management of those cases occurring in late-life.

A genome-wide association study of anorexia nervosa

Anorexia nervosa (AN) is a complex and heritable eating disorder characterized by dangerously low body weight. Neither candidate gene studies nor an initial genome-wide association study (GWAS) have yielded significant and replicated results. We performed a GWAS in 2907 cases with AN from 14 countries (15 sites) and 14 860 ancestrally matched controls as part of the Genetic Consortium for AN (GCAN) and the Wellcome Trust Case Control Consortium 3 (WTCCC3). Individual association analyses were conducted in each stratum and meta-analyzed across all 15 discovery data sets. Seventy-six (72 independent) single nucleotide polymorphisms were taken forward for in silico (two data sets) or de novo (13 data sets) replication genotyping in 2677 independent AN cases and 8629 European ancestry controls along with 458 AN cases and 421 controls from Japan. The final global meta-analysis across discovery and replication data sets comprised 5551 AN cases and 21 080 controls. AN subtype analyses (1606 AN restricting; 1445 AN binge-purge) were performed. No findings reached genome-wide significance. Two intronic variants were suggestively associated: rs9839776 (P=3.01 × 10(-7)) in SOX2OT and rs17030795 (P=5.84 × 10(-6)) in PPP3CA. Two additional signals were specific to Europeans: rs1523921 (P=5.76 × 10(-)(6)) between CUL3 and FAM124B and rs1886797 (P=8.05 × 10(-)(6)) near SPATA13. Comparing discovery with replication results, 76% of the effects were in the same direction, an observation highly unlikely to be due to chance (P=4 × 10(-6)), strongly suggesting that true findings exist but our sample, the largest yet reported, was underpowered for their detection. The accrual of large genotyped AN case-control samples should be an immediate priority for the field.

Paths to first treatment and duration of untreated illness in anorexia nervosa: are there differences according to age of onset?

This study examined paths to first treatment and the duration of untreated illness in 140 anorexia nervosa patients using validated questionnaires and a clinical interview. The differences between individuals with an early (≤14 years, n = 40), intermediate (15-18 years, n = 53) and late onset (≥19 years, n = 47) were investigated. Participants were most commonly informed about their diagnosis and first treatment facility through general practitioners and paediatricians. The duration of untreated illness exceeded 2 years in the complete sample (25.14 months) and was longest for individuals with an early onset. The early onset group was more often externally vs. internally motivated and more frequently informed about treatment options by their social network, e.g. parents, than patients with a late onset. The results emphasize the relevance of training general practitioners and paediatricians about anorexia, the need to include parents and teachers in eating disorder prevention and to improve targeting young individuals in early interventions.

A genome-wide association study on common SNPs and rare CNVs in anorexia nervosa

Anorexia nervosa (AN) is a mental illness with high mortality that most commonly afflicts adolescent female individuals. Clinical symptoms include chronic food refusal, weight loss and body image distortions. We carried out a genome-wide association study on 1033 AN cases and 3733 pediatric control subjects, all of whom were of European ancestry and were genotyped on the Illumina HumanHap610 platform (Illumina, San Diego, CA, USA). We confirmed that common single-nucleotide polymorphisms (SNPs) within OPRD1 (rs533123, P=0.0015) confer risk for AN, and obtained suggestive evidence that common SNPs near HTR1D (rs7532266, P=0.04) confer risk for restricting-type AN specifically. However, no SNPs reached genome-wide significance in our data, whereas top association signals were detected near ZNF804B, CSRP2BP, NTNG1, AKAP6 and CDH9. In parallel, we performed genome-wide analysis on copy number variations (CNVs) using the signal intensity data from the SNP arrays. We did not find evidence that AN cases have more CNVs than control subjects, nor do they have over-representation of rare or large CNVs. However, we identified several regions with rare CNVs that were only observed in AN cases, including a recurrent 13q12 deletion (1.5 Mb) disrupting SCAS in two cases, and CNVs disrupting the CNTN6/CNTN4 region in several AN cases. In conclusion, our study suggests that both common SNPs and rare CNVs may confer genetic risk to AN. These results point to intriguing genes that await further validation in independent cohorts for confirmatory roles in AN.