title: A behavioral-genetic investigation of bulimia nervosa and its relationship with alcohol use disorder.
abstract: Bulimia nervosa (BN) and alcohol use disorder (AUD) frequently co-occur and may share genetic factors; however, the nature of their association is not fully understood. We assessed the extent to which the same genetic and environmental factors contribute to liability to BN and AUD. A bivariate structural equation model using a Cholesky decomposition was fit to data from 7241 women who participated in the Swedish Twin study of Adults: Genes and Environment. The proportion of variance accounted for by genetic and environmental factors for BN and AUD and the genetic and environmental correlations between these disorders were estimated. In the best-fitting model, the heritability estimates were 0.55 (95% CI: 0.37; 0.70) for BN and 0.62 (95% CI: 0.54; 0.70) for AUD. Unique environmental factors accounted for the remainder of variance for BN. The genetic correlation between BN and AUD was 0.23 (95% CI: 0.01; 0.44), and the correlation between the unique environmental factors for the two disorders was 0.35 (95% CI: 0.08; 0.61), suggesting moderate overlap in these factors. The findings from this investigation provide additional support that some of the same genetic factors may influence liability to both BN and AUD.
authors.affiliation: Department of Psychiatry, University of North Carolina, Chapel Hill, NC, USA.
authors.forename: Sara E
authors.initials: SE
authors.lastname: Trace
authors.forename: Laura M
authors.initials: LM
authors.lastname: Thornton
authors.forename: Jessica H
authors.initials: JH
authors.lastname: Baker
authors.forename: Tammy L
authors.initials: TL
authors.lastname: Root
authors.forename: Lauren E
authors.initials: LE
authors.lastname: Janson
authors.forename: Paul
authors.initials: P
authors.lastname: Lichtenstein
authors.forename: Nancy L
authors.initials: NL
authors.lastname: Pedersen
authors.forename: Cynthia M
authors.initials: CM
authors.lastname: Bulik
mesh_terms: D000328:Adult; D019973:Alcohol-Related Disorders / Q000235:genetics*; D052018:Bulimia Nervosa / Q000235:genetics* / Q000523:psychology; D016009:Chi-Square Distribution; D004200:Diseases in Twins / Q000235:genetics*; D004777:Environment; D005260:Female; D006801:Humans; D008875:Middle Aged; D015233:Models, Statistical; D012307:Risk Factors; D013548:Sweden; D014429:Twins, Dizygotic; D014430:Twins, Monozygotic; D055815:Young Adult
keywords: Bivariate; Comorbidity; Twin study