title: Categorical and dimensional psychopathology in Dutch and US offspring of parents with bipolar disorder: A preliminary cross-national comparison.
abstract: Accumulating evidence suggests cross-national differences in adults with bipolar disorder (BD), but also in the susceptibility of their offspring (bipolar offspring). This study aims to explore and clarify cross-national variation in the prevalence of categorical and dimensional psychopathology between bipolar offspring in the US and The Netherlands.
  
  
  
  We compared levels of psychopathology in offspring of the Pittsburgh Bipolar Offspring Study (n=224) and the Dutch Bipolar Offspring Study (n=136) (age 10-18). Categorical psychopathology was ascertained through interviews using the Schedule for Affective Disorders and Schizophrenia for School Age Children (K-SADS-PL), dimensional psychopathology by parental reports using the Child Behavior Checklist (CBCL).
  
  
  
  Higher rates of categorical psychopathology were observed in the US versus the Dutch samples (66% versus 44%). We found no differences in the overall prevalence of mood disorders, including BD-I or -II, but more comorbidity in mood disorders in US versus Dutch offspring (80% versus 34%). The strongest predictors of categorical psychopathology were maternal BD (OR: 1.72, p<.05), older age of the offspring (OR: 1.19, p<.05), and country of origin (US; OR: 2.17, p<.001). Regarding comorbidity, only country of origin (OR: 7.84, p<.001) was a significant predictor. In general, we found no differences in dimensional psychopathology based on CBCL reports.
  
  
  
  Preliminary measure of inter-site reliability.
  
  
  
  We found cross-national differences in prevalence of categorical diagnoses of non-mood disorders in bipolar offspring, but not in mood disorder diagnoses nor in parent-reported dimensional psychopathology. Cross-national variation was only partially explained by between-sample differences. Cultural and methodological explanations for these findings warrant further study.
authors.affiliation: Brain Center Rudolf Magnus, Department of Psychiatry, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: Esther
authors.initials: E
authors.lastname: Mesman
authors.affiliation: Department of Psychiatry, University of Pittsburgh Medical Center, Pittsburgh, PA, USA.
authors.forename: Boris B
authors.initials: BB
authors.lastname: Birmaher
authors.affiliation: Department of Psychiatry, Sunnybrook Health Sciences Center, University of Toronto, Toronto, Canada.
authors.forename: Benjamin I
authors.initials: BI
authors.lastname: Goldstein
authors.affiliation: Department of Psychiatry, University of Pittsburgh Medical Center, Pittsburgh, PA, USA.
authors.forename: Tina
authors.initials: T
authors.lastname: Goldstein
authors.affiliation: Department of Psychiatry, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Eske M
authors.initials: EM
authors.lastname: Derks
authors.affiliation: Brain Center Rudolf Magnus, Department of Psychiatry, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: Marloes
authors.initials: M
authors.lastname: Vleeschouwer
authors.affiliation: Department of Psychiatry, University of Pittsburgh Medical Center, Pittsburgh, PA, USA.
authors.forename: Mary Beth
authors.initials: MB
authors.lastname: Hickey
authors.affiliation: Department of Psychiatry, Nationswide Children's Hospital and Ohio State College of Medicine, Columbus, USA.
authors.forename: David
authors.initials: D
authors.lastname: Axelson
authors.affiliation: Department of Psychiatry, University of Pittsburgh Medical Center, Pittsburgh, PA, USA.
authors.forename: Kelly
authors.initials: K
authors.lastname: Monk
authors.affiliation: Department of Psychiatry, University of Pittsburgh Medical Center, Pittsburgh, PA, USA.
authors.forename: Rasim
authors.initials: R
authors.lastname: Diler
authors.affiliation: Department of Psychiatry, University of Pittsburgh Medical Center, Pittsburgh, PA, USA.
authors.forename: Danella
authors.initials: D
authors.lastname: Hafeman
authors.affiliation: Department of Psychiatry, University of Pittsburgh Medical Center, Pittsburgh, PA, USA.
authors.forename: Dara J
authors.initials: DJ
authors.lastname: Sakolsky
authors.affiliation: Curium, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Catrien G
authors.initials: CG
authors.lastname: Reichart
authors.affiliation: Institute of Psychology, Erasmus University, Rotterdam, The Netherlands.
authors.forename: Marjolein
authors.initials: M
authors.lastname: Wals
authors.affiliation: Department of Child and Adolescent Psychiatry, Erasmus University Medical Center, Sophia Children's Hospital, Rotterdam, The Netherlands.
authors.forename: Frank C
authors.initials: FC
authors.lastname: Verhulst
authors.affiliation: University of Groningen, University Medical Center Groningen, Department of Psychiatry, Groningen, The Netherlands.
authors.forename: Willem A
authors.initials: WA
authors.lastname: Nolen
authors.affiliation: Brain Center Rudolf Magnus, Department of Psychiatry, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: Manon H J
authors.initials: MH
authors.lastname: Hillegers
mesh_terms: D000293:Adolescent; D000341:Affective Disorders, Psychotic / Q000453:epidemiology* / Q000209:etiology; D001714:Bipolar Disorder / Q000523:psychology*; D002648:Child; D002653:Child Behavior Disorders / Q000453:epidemiology* / Q000209:etiology; D016241:Child of Impaired Parents / Q000523:psychology*; D015897:Comorbidity; D003431:Cross-Cultural Comparison; D005006:Ethnicity; D005260:Female; D006801:Humans; D008297:Male; D009426:Netherlands / Q000453:epidemiology; D015995:Prevalence; D011599:Psychopathology; D015203:Reproducibility of Results; D012307:Risk Factors; D012559:Schizophrenia / Q000453:epidemiology* / Q000209:etiology; D014481:United States / Q000453:epidemiology
keywords: Bipolar disorder; Bipolar offspring; Child Behavior Checklist; Cross-national; High risk; Mood disorder