TY - JOUR
T1 - Genetic and environmental associations between body dissatisfaction, weight preoccupation, and binge eating
T2 - Evidence for a common factor with differential loadings across symptom type
AU - O'Connor, Shannon M.
AU - Beam, Christopher R.
AU - Luo, Xiaochen
AU - Cohen, L. Adelyn
AU - VanHuysse, Jessica L.
AU - Emery, Robert E.
AU - Turkheimer, Eric
AU - Keel, Pamela K.
AU - Burt, S. Alexandra
AU - Neale, Michael
AU - Boker, Steven
AU - Klump, Kelly
N1 - Funding Information:
We found lower factor loadings for BE and a higher proportion of BE-specific genetic and nonshared environmental influences compared to other disordered eating symptoms. While factor loadings for WP and BD were not equal, both loaded more strongly on the common factor than BE. Thus, similar to studies that demonstrate cross-disorder gene sharing, our results suggest that disordered eating symptoms share a set of common genetic and environmental risk factors. However, our findings substantially advance this literature by showing that BE also exhibits unique etiologic effects. Moving forward, it will be important to identify the common and unique mechanisms contributing to different types of disordered eating. One potential framework is the National Institute of Mental Health's Research Domain Criteria (RDoC). The common factor identified herein may be linked to the RDoC negative valence domain, which is characterized by systems primarily responsible for negative affect and anxiety. These systems are important for all types of eating disorders, including those characterized by BE. By contrast, positive valence domain systems have been more strongly linked to BE and overeating (e.g., Bello and Hajnal (2010)). Indeed, these systems are responsible for appetitive responses to reward and may contribute to BE beyond the effects of the negative valence domain systems. Clearly, the mechanisms contributing to common/unique effects go beyond these neurological and biological processes, as residual nonshared environmental influences were much larger for BE than the other symptoms. Nonetheless, the RDoC negative and positive valence domains provide a unifying framework for examining the genetic, neurobiological, and environmental factors that likely contribute to common and unique risk factors across eating disorders and their symptoms. Our study was not without limitations. We used a population-based sample and it is unknown if results extend to clinical populations. However, recent data suggest that binge eating exists on a continuum with clinical eating disorders, and thus, results likely extend to clinical populations as well. Disordered eating was assessed with a self-report questionnaire. Future studies should test whether these results extend to interview-based measures. Ideally, these investigations should investigate a wider array of symptoms to inform etiological models and classification systems across the spectrum of pathology. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institute of Mental Health or Michigan State University. None of the authors have financial conflicts of interest.
Publisher Copyright:
© 2016 Wiley Periodicals, Inc.
PY - 2017/2/1
Y1 - 2017/2/1
N2 - Objective: Prior twin studies provide support for a single “common factor” that contributes genetic and environmental risk to a range of disordered eating symptoms. However, the common factor may be indexed less well by binge eating (BE) than other symptoms of eating disorders [i.e., body dissatisfaction (BD) and weight preoccupation (WP)]. We sought to explore the presence of a common factor and test whether loadings differed across three key symptoms (i.e., BE, BD, WP). Method: Disordered eating was assessed via self-report in 631 female twin pairs from the Michigan State University Twin Registry. Results: We detected a common disordered eating factor that was influenced primarily by additive genetic and nonshared environmental influences. However, we observed different loadings on this common factor by symptom type, as factor loadings for BD and WP were stronger than that for BE. Moreover, the residual environmental and/or genetic variances (i.e., those that are independent of the common factor) were larger in BE than those of BD or WP. Discussion: Although all three symptoms share a common set of genetic and environmental influences, risk for BE may involve additional genetic, biological, and environmental factors that are not shared with other symptoms of eating pathology.
AB - Objective: Prior twin studies provide support for a single “common factor” that contributes genetic and environmental risk to a range of disordered eating symptoms. However, the common factor may be indexed less well by binge eating (BE) than other symptoms of eating disorders [i.e., body dissatisfaction (BD) and weight preoccupation (WP)]. We sought to explore the presence of a common factor and test whether loadings differed across three key symptoms (i.e., BE, BD, WP). Method: Disordered eating was assessed via self-report in 631 female twin pairs from the Michigan State University Twin Registry. Results: We detected a common disordered eating factor that was influenced primarily by additive genetic and nonshared environmental influences. However, we observed different loadings on this common factor by symptom type, as factor loadings for BD and WP were stronger than that for BE. Moreover, the residual environmental and/or genetic variances (i.e., those that are independent of the common factor) were larger in BE than those of BD or WP. Discussion: Although all three symptoms share a common set of genetic and environmental influences, risk for BE may involve additional genetic, biological, and environmental factors that are not shared with other symptoms of eating pathology.
KW - binge eating
KW - body dissatisfaction
KW - common factor
KW - eating disorders
KW - twins
KW - weight preoccupation
UR - http://www.scopus.com/inward/record.url?scp=84987924154&partnerID=8YFLogxK
U2 - 10.1002/eat.22625
DO - 10.1002/eat.22625
M3 - Article
C2 - 27636116
AN - SCOPUS:84987924154
SN - 0276-3478
VL - 50
SP - 157
EP - 161
JO - International Journal of Eating Disorders
JF - International Journal of Eating Disorders
IS - 2
ER -