Shared transmission of eating disorders and anxiety disorders.
OBJECTIVE
Eating disorders have high comorbidity with mood, anxiety, and substance use disorders. Using twins from the population-based Minnesota Twin Family Study (MTFS), we examined comorbidity and shared transmission between eating pathology and these disorders.


METHODS
Female twins (N = 672), ages 16-18 years, completed structured clinical interviews assessing anorexia nervosa and bulimia nervosa (as described in the 4th ed. of the Diagnostic and Statistical Manual of Mental Disorders [DSM-IV; American Psychiatric Association, 1994]), as well as mood, anxiety, and substance use disorders (as described in the 3rd Rev. ed. of the Diagnostic and Statistical Manual of Mental Disorders [DSM-III-R]). Shared transmission was examined using a discordant monozygotic (MZ) twin design.


RESULTS
Significant comorbidity was found between eating disorders and major depression, anxiety disorders, and nicotine dependence. Within MZ twin pairs discordant for eating disorders (n = 14), non-eating-disordered cotwins demonstrated increased risk for anxiety disorders compared with controls. Similarly, within MZ twin pairs discordant for anxiety disorders (n = 52), non-anxiety-disordered cotwins demonstrated increased risk for eating disorders compared with controls.


CONCLUSIONS
Findings support shared transmission between eating disorders and anxiety disorders. However, the nature of this shared diathesis remains unknown.
Keel
Pamela K
PK
Department of Psychology, University of Iowa, Iowa City, Iowa 55242, USA. Pamela-keel@uiowa.edu
Klump
Kelly L
KL
Miller
Kathryn B
KB
McGue
Matt
M
Iacono
William G
WG
D000293:Adolescent; D001008:Anxiety Disorders / Q000453:epidemiology* / Q000235:genetics*; D016022:Case-Control Studies; D015897:Comorbidity; D004200:Diseases in Twins / Q000453:epidemiology* / Q000235:genetics*; D001068:Feeding and Eating Disorders / Q000453:epidemiology* / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease / Q000453:epidemiology*; D006801:Humans; D001523:Mental Disorders / Q000453:epidemiology / Q000235:genetics; D015995:Prevalence; D014430:Twins, Monozygotic; D014481:United States / Q000453:epidemiology