Study offers genetic and phenotypic links to disordered eating, mental health

A high BMI early in life was tied to later fasting, while neuroticism, alcohol and drug use, and self-harm was linked with later binge eating in adolescents, researchers reported.

In a cohort of over 1,000 teens, more than half of whom were girls, 17.1% reported binge eating, 20.6% reported purging, and 21.9% reported dieting at ages 14, 16, or 19, according to Sylvane Desrivières, PhD, of the Centre for Population Neuroscience and Precision Medicine, Institute of Psychiatry, Psychology & Neuroscience, in London, and co-authors.

And, among the precursors of disordered eating behaviors (DEB), high BMI was associated with future dieting (odds ratio 3.44, 95% CI 2.09 to 5.65), and high levels of neuroticism (OR 1.04, 95% CI 1.01 to 1.06), conduct problems (OR 1.41, 95% CI 1.17 to 1.69), and deliberate self-harm (OR 2.18, 95% CI 1.37 to 3.45) were associated with future binge eating, they stated in JAMA Network Open.

The DEBs also predated other, future mental health problems, the authors noted, suggesting that “difficulty regulating emotions is an important characteristic of individuals at risk of developing binge-eating behaviors,” according to Desrivières’ group.

Using a population from the IMAGEN study, the authors looked at BMI, mental health symptoms, substance use behaviors, and personality variables as time-varying associations of dieting, binge eating, and purging, or change in BMI over time. They also calculated polygenic risk scores were calculated to evaluate genetic contributions associated with BMI, attention-deficit-hyperactivity disorder (ADHD) and neuroticism to DEBs.

“This study highlights the value of analyzing data from longitudinal cohort studies with measures across psychological and biological domains. This approach enables researchers to hypothesize and test complex models, which are more likely to approximate the true origins of onset of common mental health illnesses, such as eating disorders,” noted Moritz Herle, PhD, of King’s College, and Carol Kan, PhD, of St. Ann’s Hospital, both in London, in an invited commentary accompanying the study.

The take-home message for primary care physicians from the study is that there is need for “greater clinical awareness and prompter recognition of psychiatric comorbidities” because of the connections between childhood mental health issues and adolescent affective disorders with eating disorder symptoms, they wrote.

Desrivières and co-authors evaluated 1,623 European adolescents (51.1% girls), who were recruited at a mean age of 14.5. They were followed up at ages 16 and 19. Participants were financially compensated for being in the study, they noted.

Mental health disorders, alcohol and substance abuse, and emotional and behavioral problems were assessed with various established scales, such as the Development and Well-Being Assessment, the Alcohol Use Disorders Identification Test, the Strengths and Difficulties Questionnaire, and the Neuroticism-Extraversion Openness Five-Factor Inventory. For the genetic analysis, “After quality control, 1975 cases and 502 single-nucleotide variations with alternative bases at nucleotide 160 were available for polygenetic risk score (PRS) analyses,” the authors explained.

They reported that the BMI PRS were associated with:

  • Dieting: OR 1.27 at age 14 (lower bound 95% CI 1.08); OR 1.38 at age 16 (lower bound 95% CI 1.17).
  • Purging: OR 1.34 at age 14 (lower bound 95% CI 1.12); OR 1.32 at age 16 (lower bound 95% CI 1.14).

The ADHD PRS was linked with purging at age 16 (OR 1.25, lower bound 95% CI 1.08) and at age 19 (OR 1.23, lower bound 95% CI 1.06).

Lastly, the full-scale neuroticism PRS was associated with binge eating at age 14 years (OR 1.32, lower bound 95% CI 1.11) and at age 16 (OR 1.24, lower bound 95% CI 1.06). For two neuroticism subcomponents and their contribution to binge eating, the authors found significant associations with the PRS for depressed affect at age 14 (OR 1.34, lower bound 95% CI 1.12) and at age 16 (OR 1.29, lower bound 95% CI 1.09). However, there was no significiant association with the PRS for worry.

They stated that BMI PRS “explained 5.15% (P<.01) of the variance in BMI at 14 years,” while “The ADHD PRS… explained 1.11% of the variance of ADHD symptoms at 14 years, and neuroticism PRS “explained 1.64% of the variance in neuroticism at 14 years.” Also, the “PRS associated with depressed affect explained 0.86% of the neuroticism variance at 14 years, and worry explained 0.17% of the neuroticism variance at 14 years.”

Ultimately, the PRS BM data highlighted “distinct etiologic overlaps between these traits,” Desrivières stated.

And the DEBs predated other mental health problems, with dieting at age 14 tied to future symptoms of depression (OR 2.53, 95% CI 1.56 to 4.10), generalized anxiety (OR 2.27, 95% CI 1.14 to 4.51), deliberate self-harm (OR 2.10, 95% CI 1.51 to 4.24), emotional problems (OR 1.24, 95% CI 1.08 to 1.43), and smoking (OR 2.16, 95% CI 1.36 to 3.48). Finally, purging at age 14 was associated with future depression (OR 2.87, 95% CI 1.69 to 5.01) and anxiety (OR 2.48, 95% CI 1.49 to 4.12) symptoms.

Study limitations included the fact that there were not many boys reporting DEBs, a lack of socioeconomic data, and the fact that the authors only captured DEBs from age 14 on.

However, the authors pointed out that “the finding that early ADHD symptoms, personality traits (low levels of agreeableness), alcohol and drug misuse, and self-harm were associated with the development of purging is novel” and that “Together, our findings suggest that genetic predispositions and psychopathologic processes associated with obesity, ADHD, and depression may be useful early and differential biomarkers of the vulnerability for eating disorders in adolescence.”

  1. BMI, neuroticism, impulse control, and addiction-related behaviors at age 14 were differentially associated with future disordered eating behaviors and symptoms of depression and generalized anxiety.

  2. Genetic analyses suggested etiologic overlaps between BMI, neuroticism, and attention-deficit-hyperactivity disorder with dieting, binge eating, and purging, respectively.

Shalmali Pal, Contributing Writer, BreakingMED™

The study was supported by the Medical Research Foundation, Medical Research Council (MRC), FP6 Integrated Project IMAGEN, Horizon 2020-funded ERC Advanced Grant, European Research Network on Elicit Drugs, European Union Joint Programme Neurodegenerative Disease Research, Brain Imaging, Cognition Dementia and Next Generation Genomics, Human Brain Project, FP7 project METRICS, MRC Grant and c-VEDA, National Institute for Health Research (NIHR) Biomedical Research Centre (BRC) at South London and Maudsley NHS Foundation Trust (SLAM) and King’s College London (KCL), Bundesministerium für Bildung und Forschung (BMBF), the German Research Council (DFG), the NIH, Fondation de France, Fondation pour la Recherche Médicale, Mission Interministérielle de Lutte-contre-les-Drogues-et-les-Conduites-Addictives, Assistance-Publique-Hôpitaux-de-Paris, INSERM, Paris Sud University, Fondation de l’Avenir, the Fédération pour la Recherche sur le Cerveau, and the National Science Foundation.

Desrivières reported support from the MRC and from the Medical Research Foundation. Co-authors reported support from, and/or relationships with, NIHR BRC SLAM KCL, Fudan University, the National Natural Science Foundation China, the Shanghai Municipal Science and Technology Commission, GE Healthcare, Infectopharm, Lilly, Lundbeck, Medice, Neurim Pharmaceuticals, Novartis, Oberberg GmbH, Shire, Takeda, Vifor Pharma, CIP Medien, Hogrefe, Kohlhammer, Oxford University Press, the National Children’s Hospital Foundation-Tallaght, the French National Research Agency, Fondation de l’Avenir, Fondation de France, Inserm, Hogrefe, European Union FP6/Horizon 2020, the German Federal Ministry of Education and Research, DFG, BMBF, and the European Commission.

Herle reported support from the MRC. Kan reported support from, and or relationships with, the NIHR, Novo Nordisk UK Research Foundation, Marie Curie Fellowship, and the Lundbeck Foundation.

Cat ID: 140

Topic ID: 85,140,496,795,140,252,477,478,518,917