The role of prenatal and perinatal factors in eating disorders: a systematic review

Interplay of polygenic liability with birth-related, somatic, and psychosocial factors in anorexia nervosa risk: a nationwide study

BACKGROUND

Although several types of risk factors for anorexia nervosa (AN) have been identified, including birth-related factors, somatic, and psychosocial risk factors, their interplay with genetic susceptibility remains unclear. Genetic and epidemiological interplay in AN risk were examined using data from Danish nationwide registers. AN polygenic risk score (PRS) and risk factor associations, confounding from AN PRS and/or parental psychiatric history on the association between the risk factors and AN risk, and interactions between AN PRS and each level of target risk factor on AN risk were estimated.

METHODS

Participants were individuals born in Denmark between 1981 and 2008 including nationwide-representative data from the iPSYCH2015, and Danish AN cases from the Anorexia Nervosa Genetics Initiative and Eating Disorder Genetics Initiative cohorts. A total of 7003 individuals with AN and 45 229 individuals without a registered AN diagnosis were included. We included 22 AN risk factors from Danish registers.

RESULTS

Risk factors showing association with PRS for AN included urbanicity, parental ages, genitourinary tract infection, and parental socioeconomic factors. Risk factors showed the expected association to AN risk, and this association was only slightly attenuated when adjusted for parental history of psychiatric disorders or/and for the AN PRS. The interaction analyses revealed a differential effect of AN PRS according to the level of the following risk factors: sex, maternal age, genitourinary tract infection, C-section, parental socioeconomic factors and psychiatric history.

CONCLUSIONS

Our findings provide evidence for interactions between AN PRS and certain risk-factors, illustrating potential diverse risk pathways to AN diagnosis.

Exposures during pregnancy and at birth are associated with the risk of offspring eating disorders

BACKGROUND

Eating disorders (ED) are severe psychiatric disorders, commonly debuting early. Aberrances in the intrauterine environment and at birth have been associated with risk of ED. Here, we explore if, and at what effect size, a variety of such exposures associate with offspring ED, that is, anorexia nervosa (AN), bulimia nervosa (BN), and eating disorder not otherwise specified (EDNOS).

METHODS

This population-based cohort study, conducted from September 2021 to August 2023, used Finnish national registries of all live births in 1996-2014 (N = 1,097,753). Cox proportional hazards modeling was used to compare ED risk in exposed versus unexposed offspring, adjusting for potential confounders and performing sex-stratified analyses.

RESULTS

A total of 6614 offspring were diagnosed with an ED; 3668 AN, 666 BN, and 4248 EDNOS. Lower risk of offspring AN was seen with young mothers, continued smoking, and instrumental delivery, while higher risk was seen with older mothers, inflammatory disorders, prematurity, small for gestational age, and low Apgar. Offspring risk of BN was higher with continued smoking and prematurity, while lower with postmature birth. Offspring risk of EDNOS was lower with instrumental delivery, higher for older mothers, polycystic ovary syndrome, insulin-treated pregestational diabetes, antibacterial treatment, prematurity, and small for gestational age. Sex-specific associations were found.

CONCLUSIONS

Several prenatal and at birth exposures are associated with offspring ED; however, we cannot exclude confounding by maternal BMI. Nevertheless, several exposures selectively associate with risk of either AN, BN, or EDNOS, and some are sex-specific, emphasizing the importance of subtype- and sex-stratified analyses of ED.

PUBLIC SIGNIFICANCE

We define environmental factors involved in the development of different ED, of importance as preventive measure, but also in order to aid in defining the molecular pathways involved and thus in the longer perspective contribute to the development of pharmacological treatment of ED.

Birth-related, medical, and diagnostic characteristics in younger versus older children with avoidant/restrictive food intake disorder (ARFID)

BACKGROUND

Although avoidant/restrictive food intake disorder (ARFID) presents the replacement and extension of feeding disorders of infancy and childhood, previous research into ARFID concentrated mainly on older patients. While birth-related characteristics play an etiologic role in feeding disorders, virtually nothing is known so far in ARFID. Therefore, the first aim of the study was to identify differences in birth-related characteristics in younger vs. older children with ARFID. Second, differences in physical and mental comorbidities, and third, diagnostic features between age groups were analysed.

METHODS

Among N = 51 in- and outpatient treatment-seeking patients, n = 23 patients aged 0-5 years (30% girls) and n = 28 patients aged 6-17 years (57% girls), with an interview-based diagnosis of ARFID were included. Data on the pre- and perinatal period and mental and physical comorbidities were derived from patients' medical records, while diagnostic criteria, main ARFID presentation, and sociodemographic variables were collected through diagnostic interview.

RESULTS

Significantly, younger patients with ARFID were born more often preterm and had more pre- and perinatal complications and a higher incidence of postnatal invasive procedures. Patients with ARFID aged 0-5 years presented significantly more physical comorbidities and conditions, especially congenital anomalies, while mental comorbidities, especially mood disorders, were significantly more common in patients with ARFID aged 6-17 years. No age differences were found for the distribution of diagnostic criteria and main ARFID presentation.

CONCLUSION

This is the first study which aimed to identify age-specific characteristics in patients with ARFID with potential relevance for diagnosis and treatment. Especially birth-related complications, including invasive procedures postnatally, may be associated with developing ARFID, highlighting the importance of a closer view on these potential risk factors of the disorder. Future research with longitudinal design and larger samples may allow more detailed information on further age-specific associations, symptom trajectories, and age-specific risk factors for ARFID.

Childhood body mass index and the subsequent risk of anorexia nervosa and bulimia nervosa among women: A large Danish population-based study

OBJECTIVE

Evidence linking childhood body mass index (BMI) with subsequent eating disorders is equivocal. Potential explanations include different study populations and size, and that anorexia nervosa (AN) and bulimia nervosa (BN) should be studied separately. We examined whether birthweight and childhood BMI were associated with subsequent risk of AN and BN in girls.

METHOD

We included 68,793 girls from the Copenhagen School Health Records Register born between 1960 and 1996 with information on birthweight and measured weights and heights obtained from school health examinations at ages 6-15 years. Diagnoses of AN and BN were retrieved from Danish nationwide patient registers. We used Cox proportional hazards regression to estimate hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

We identified 355 cases of AN (median age: 19.0) and 273 cases of BN (median age: 21.8). Higher childhood BMI was linearly associated with decreasing risk of AN and increasing risk of BN at all childhood ages. At age 6, the HR for AN was 0.85 (95% CI: 0.74-0.97) per BMI z-score and the HR for BN was 1.78 (95% CI: 1.50-2.11) per BMI z-score. Birthweight >3.75 kg was associated with increased risk of BN compared to a birthweight of 3.26-3.75 kg.

CONCLUSION

Higher BMI in girls at ages 6-15 years was associated with decreasing risk of AN and increasing risk of BN. Premorbid BMI could be relevant for the etiology of AN and BN, and in identifying high risk individuals.

PUBLIC SIGNIFICANCE

Eating disorders are associated with elevated mortality, especially AN. Using a cohort of Copenhagen school children, we linked information on BMI at ages 6-15 years for 68,793 girls with nationwide patient registers. Low childhood BMI was associated with increased risk of AN, whereas high childhood BMI was associated with increased risk of BN. These findings may assist clinicians in identifying individuals at high-risk of these diseases.

Risk factors for eating disorders: findings from a rapid review

BACKGROUND

Risk factors represent a range of complex variables associated with the onset, development, and course of eating disorders. Understanding these risk factors is vital for the refinement of aetiological models, which may inform the development of targeted, evidence-based prevention, early intervention, and treatment programs. This Rapid Review aimed to identify and summarise research studies conducted within the last 12 years, focusing on risk factors associated with eating disorders.

METHODS

The current review forms part of a series of Rapid Reviews to be published in a special issue in the Journal of Eating Disorders, funded by the Australian Government to inform the development of the National Eating Disorder Research and Translation Strategy 2021-2031. Three databases were searched for studies published between 2009 and 2021, published in English, and comprising high-level evidence studies (meta-analyses, systematic reviews, moderately sized randomised controlled studies, moderately sized controlled-cohort studies, or population studies). Data pertaining to risk factors for eating disorders were synthesised and outlined in the current paper.

RESULTS

A total of 284 studies were included. The findings were divided into nine main categories: (1) genetics, (2) gastrointestinal microbiota and autoimmune reactions, (3) childhood and early adolescent exposures, (4) personality traits and comorbid mental health conditions, (5) gender, (6) socio-economic status, (7) ethnic minority, (8) body image and social influence, and (9) elite sports. A substantial amount of research exists supporting the role of inherited genetic risk in the development of eating disorders, with biological risk factors, such as the role of gut microbiota in dysregulation of appetite, an area of emerging evidence. Abuse, trauma and childhood obesity are strongly linked to eating disorders, however less conclusive evidence exists regarding developmental factors such as role of in-utero exposure to hormones. Comorbidities between eating disorders and mental health disorders, including personality and mood disorders, have been found to increase the severity of eating disorder symptomatology. Higher education attainment, body image-related factors, and use of appearance-focused social media are also associated with increased risk of eating disorder symptoms.

CONCLUSION

Eating disorders are associated with multiple risk factors. An extensive amount of research has been conducted in the field; however, further studies are required to assess the causal nature of the risk factors identified in the current review. This will assist in understanding the sequelae of eating disorder development and in turn allow for enhancement of existing interventions and ultimately improved outcomes for individuals.

The early life course-related traits with three psychiatric disorders: A two-sample Mendelian randomization study

Objectives

Several studies have indicated a potential association between early life course-related traits and neurological and psychiatric disorders in adulthood, but the causal link remains unclear.

Methods

Instrumental variables (IVs) that have been shown to be strongly associated with exposure were obtained from summary data of genome-wide association studies (GWASs). Four early life course-related traits [i.e., birthweight (BW), childhood body mass index (BMI), early body size, and age at first birth (AFB)] were used as exposure IVs to estimate their causal associations with three neurological and psychiatric diseases [i.e., Alzheimer's disease (AD), major depressive disorder (MDD), and attention-deficit hyperactivity disorder (ADHD)]. Four different statistical methods, i.e., inverse-variance weighting (IVW), MR-Egger (MRE), weighted median (WM), and weighted mode (Wm), were performed in our MR analysis. Sensitivity analysis was performed by using the leave-one-out method, and horizontal pleiotropy was assessed using the MR-PRESSO package.

Results

There was evidence suggesting that BW has a causal effect on AD (OR_MR-PRESSO = 1.05, p = 1.14E-03), but this association was not confirmed via multivariable Mendelian randomization (MVMR) (OR_MVMR = 0.97, 95% CI 0.92-1.02, p = 3.00E-01). A strong relationship was observed between childhood BMI and ADHD among both sexes; a 1-SD increase in BMI significantly predicted a 1.46-fold increase in the OR for ADHD (p = 9.13E-06). In addition, a similar relationship was found between early life body size and ADHD (OR_MR-PRESSO = 1.47, p = 9.62E-05), and this effect was mainly driven by male participants (OR_MR-PRESSO = 1.50, p = 1.28E-3). Earlier AFB could significantly predict a higher risk of MDD (OR_MR-PRESSO = 1.19, p = 1.96E-10) and ADHD (OR_MR-PRESSO = 1.45, p = 1.47E-15). No significant causal associations were observed between the remaining exposures and outcomes.

Conclusion

Our results reveal the adverse effects of childhood obesity and preterm birth on the risk of ADHD later in life. The results of MVMR also show that lower BW may have no direct relationship with AD after adjusting for BMI. Furthermore, AFB may predict a higher risk of MDD.

Mechanisms by which adverse childhood experiences, other traumas and PTSD influence the health and well-being of individuals with eating disorders throughout the life span

BACKGROUND

Multiple published sources from around the world have confirmed an association between an array of adverse childhood experiences (ACEs) and other traumatic events with eating disorders (EDs) and related adverse outcomes, including higher morbidity and mortality.

METHODS

In keeping with this Special Issue's goals, this narrative review focuses on the ACEs pyramid and its purported mechanisms through which child maltreatment and other forms of violence toward human beings influence the health and well-being of individuals who develop EDs throughout the life span. Relevant literature on posttraumatic stress disorder (PTSD) is highlighted when applicable.

RESULTS

At every level of the pyramid, it is shown that EDs interact with each of these proclaimed escalating mechanisms in a bidirectional manner that contributes to the predisposition, precipitation and perpetuation of EDs and related medical and psychiatric comorbidities, which then predispose to early death. The levels and their interactions that are discussed include the contribution of generational embodiment (genetics) and historical trauma (epigenetics), social conditions and local context, the ACEs and other traumas themselves, the resultant disrupted neurodevelopment, subsequent social, emotional and cognitive impairment, the adoption of health risk behaviors, and the development of disease, disability and social problems, all resulting in premature mortality by means of fatal complications and/or suicide.

CONCLUSIONS

The implications of these cascading, evolving, and intertwined perspectives have important implications for the assessment and treatment of EDs using trauma-informed care and trauma-focused integrated treatment approaches. This overview offers multiple opportunities at every level for the palliation and prevention of EDs and other associated trauma-related conditions, including PTSD.

Treatment of eating disorders: A systematic meta-review of meta-analyses and network meta-analyses

MONTELEONE, A.M., F. Pellegrino, G. Croatto, M. Carfagno, A. Hilbert, J. Treasure, T. Wade, C. Bulik, S. Zipfel, P. Hay, U. Schmidt, G. Castellini, A. Favaro, F. Fernandez-Aranda, J. Il Shin, U. Voderholzer, V. Ricca, D. Moretti, D. Busatta, G. Abbate-Daga, F. Ciullini, G. Cascino, F. Monaco, C.U. Correll and M. Solmi. Treatment of Eating Disorders: a systematic meta-review of meta-analyses and network meta-analyses. NEUROSCI BIOBEHAV REV 21(1) XXX-XXX, 2022.- Treatment efficacy for eating disorders (EDs) is modest and guidelines differ. We summarized findings/quality of (network) meta-analyses (N)MA of randomized controlled trials (RCTs) in EDs. Systematic meta-review ((N)MA of RCTs, ED, active/inactive control), using (anorexia or bulimia or eating disorder) AND (meta-analy*) in PubMed/PsycINFO/Cochrane database up to December 15th, 2020. Standardized mean difference, odds/risk ratio vs control were summarized at end of treatment and follow-up. Interventions involving family (family-based therapy, FBT) outperformed active control in adults/adolescents with anorexia nervosa (AN), and in adolescents with bulimia nervosa (BN). In adults with BN, individual cognitive behavioural therapy (CBT)-ED had the broadest efficacy versus active control; also, antidepressants outperformed active. In mixed age groups with binge-eating disorder (BED), psychotherapy, and lisdexamfetamine outperformed active control. Antidepressants, stimulants outperformed placebo, despite lower acceptability, as did CBT-ED versus waitlist/no treatment. Family-based therapy is effective in AN and BN (adolescents). CBT-ED has the largest efficacy in BN (adults), followed by antidepressants, as well as psychotherapy in BED (mixed). Medications have short-term efficacy in BED (adults).

Feeding Difficulty Among Chinese Toddlers Aged 1-3 Years and Its Association With Health and Development

Feeding problems are biopsychosocial in nature and have a great influence on children's growth. The aim of this study was to profile the status and possible influencing factors of feeding difficulty among normal Chinese toddlers, and to investigate its association with health and development. This study is a part of the Young Investigation (YI study) conducted in 10 cities in China. Data from 924 children aged 1-3 years were analyzed. Data on socio-demographic factors, feeding behaviors, self-reported diseases, and anthropometry parameters were collected. Blood samples were drawn to determine hemoglobin levels. Feeding difficulty was evaluated by the Montreal Children's Hospital Feeding Scale (MCH-FS). Ages and Stages Questionnaires, Third Edition (ASQ-3) were used to assess developmental progress. Multivariable analyses were performed to explore the potential associations. The mean total score of the MCH-FS was 35.21 ± 12.90 and the highest scored item was "acting up/making a big fuss during mealtimes." Feeding difficulty occurred more often among children with picky eating behavior or whose caregivers once used the strategy of pre-mastication. Children with feeding difficulty had lower intakes of cereals, vegetables, and fruits, and were more likely to suffer from diarrhea (OR, 2.04; 95%CI: 1.32, 3.11) or constipation (OR, 2.04; 95%CI: 1.27, 3.24), but not anemia. Feeding difficulty was also negatively associated with weight, height, head circumference and mid-upper-arm circumference-related Z-scores (P all < 0.05). In addition, it was related to poorer fine motor skills, personal and social skills, and total scores of ASQ-3 (β, -9.00; 95%CI: -15.11, -2.89). Feeding difficulty assessed by MCH-FS showed a negative association with children's health and development, supporting the need for early identification.