title: Childhood adversity and psychosis: examining whether the association is due to genetic confounding using a monozygotic twin differences approach.
abstract: OBJECTIVE
  To test whether the association between childhood adversity and positive and negative psychotic experiences is due to genetic confounding.
  
  
  METHODS
  Childhood adversity and psychotic experiences were assessed in an ongoing sample of 226 twins from the general population. A monozygotic (MZ) twin differences approach was used to assess possible genetic confounding.
  
  
  RESULTS
  In the whole sample, childhood adversity was significantly associated with positive (β=45; SE=0.16; P=0.008) and negative psychotic experiences (β=0.77; SE=0.18; P<0.01). Within-pair MZ twin differences in exposure to childhood adversity were significantly associated with differences in positive (β=71; SE=0.29; P=0.016) and negative psychotic experiences (β=98; SE=0.38; P=0.014) in a subsample of 85 MZ twin pairs.
  
  
  CONCLUSIONS
  Individuals exposed to childhood adversity are more likely to report psychotic experiences. Furthermore, our findings indicate that this association is not due to genetic confounding.
authors.affiliation: Anthropology Unit, Department of Animal Biology, Faculty of Biology, University of Barcelona, Avenue Diagonal 643, 08028 Barcelona, Spain.
authors.forename: S
authors.initials: S
authors.lastname: Alemany
authors.forename: X
authors.initials: X
authors.lastname: Goldberg
authors.forename: R
authors.initials: R
authors.lastname: van Winkel
authors.forename: C
authors.initials: C
authors.lastname: Gastó
authors.forename: V
authors.initials: V
authors.lastname: Peralta
authors.forename: L
authors.initials: L
authors.lastname: Fañanás
mesh_terms: D000293:Adolescent; D054523:Adult Survivors of Child Abuse / Q000523:psychology; D002648:Child; D002649:Child Abuse / Q000523:psychology*; D004200:Diseases in Twins / Q000235:genetics* / Q000523:psychology; D005260:Female; D006801:Humans; D008875:Middle Aged; D011618:Psychotic Disorders / Q000235:genetics* / Q000523:psychology; D012307:Risk Factors; D012931:Social Environment; D014430:Twins, Monozygotic / Q000235:genetics* / Q000523:psychology