title: Prevalence of and familial influences on purging disorder in a community sample of female twins.
abstract: OBJECTIVE
  Purging disorder (PD) was recently included as an otherwise specified feeding or eating disorder (OSFED) in the DSM-5; however, limited information is available on its prevalence, and its etiology is unknown.
  
  
  METHODS
  Data from 1,790 monozygotic and 1,440 dizygotic European American female twins (age range = 18-29 years) from the Missouri Adolescent Female Twin Study were used to investigate prevalence and familial influences for PD. A structured clinical interview assessed lifetime DSM-IV criteria for eating disorders and PD. After adjustment for age, twin correlations and biometrical twin models were used to estimate familial (i.e., genetic plus shared environmental) influences on PD.
  
  
  RESULTS
  One hundred and twenty one (3.77%; 95% CI: 3.14, 4.49) women met criteria for lifetime PD. Twin correlations suggested that genetic, shared environmental, and nonshared environmental factors influenced liability to PD. Nonshared environmental factors accounted for 56% [35%, 79%] of the variance in PD. Although familial effects accounted for a significant proportion of variance (44% [21%, 65%]), it was not possible to disentangle the independent contributions of additive genetic effects (20% [0%, 65%]) and shared environmental effects (24% [0%, 57%]).
  
  
  CONCLUSIONS
  PD is a prevalent form of eating pathology. Familial factors are relevant to the development of PD but do not demonstrate the magnitude of heritable factors found for other eating disorders.
authors: Department of Psychiatry and Midwest Alcoholism Research Center, Washington University School of Medicine, St. Louis, Missouri.
authors: Melissa A
authors: MA
authors: Munn-Chernoff
authors: Department of Psychology, Florida State University, Tallahassee, Florida.
authors: Pamela K
authors: PK
authors: Keel
authors: Department of Psychology, Michigan State University, East Lansing, Michigan.
authors: Kelly L
authors: KL
authors: Klump
authors: Department of Psychiatry and Midwest Alcoholism Research Center, Washington University School of Medicine, St. Louis, Missouri.
authors: Julia D
authors: JD
authors: Grant
authors: Department of Psychiatry and Midwest Alcoholism Research Center, Washington University School of Medicine, St. Louis, Missouri.
authors: Kathleen K
authors: KK
authors: Bucholz
authors: Department of Psychiatry and Midwest Alcoholism Research Center, Washington University School of Medicine, St. Louis, Missouri.
authors: Pamela A F
authors: PA
authors: Madden
authors: Department of Psychiatry and Midwest Alcoholism Research Center, Washington University School of Medicine, St. Louis, Missouri.
authors: Andrew C
authors: AC
authors: Heath
authors: Department of Psychiatry and Midwest Alcoholism Research Center, Washington University School of Medicine, St. Louis, Missouri.|George Warren Brown School of Social Work, Washington University, St. Louis, Missouri.
authors: Alexis E
authors: AE
authors: Duncan
mesh_terms: D000328:Adult; D015331:Cohort Studies; D004200:Diseases in Twins / Q000235:genetics*; D001068:Feeding and Eating Disorders / Q000235:genetics*; D005260:Female; D006801:Humans; D015995:Prevalence; D014429:Twins, Dizygotic; D055815:Young Adult
keywords: eating disorders; genetics; purging disorder; twins; women