Get access

Psychosis-inducing effects of cannabis are related to both childhood abuse and COMT genotypes

Authors

  • S. Alemany,

    1. Anthropology Unit, Department of Animal Biology, Faculty of Biology, University of Barcelona, Barcelona, Spain
    2. Biomedicine Institute of the University of Barcelona (IBUB), Barcelona, Spain
    3. Centre for Biomedical Research Network on Mental Health (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
    Search for more papers by this author
  • B. Arias,

    1. Anthropology Unit, Department of Animal Biology, Faculty of Biology, University of Barcelona, Barcelona, Spain
    2. Biomedicine Institute of the University of Barcelona (IBUB), Barcelona, Spain
    3. Centre for Biomedical Research Network on Mental Health (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
    Search for more papers by this author
  • M. Fatjó-Vilas,

    1. Anthropology Unit, Department of Animal Biology, Faculty of Biology, University of Barcelona, Barcelona, Spain
    2. Biomedicine Institute of the University of Barcelona (IBUB), Barcelona, Spain
    Search for more papers by this author
  • H. Villa,

    1. Department of Basic Psychology, Clinical and Psychobiology, Faculty of Human and Social Sciences, Univerity Jaume I, Castelló, Spain
    Search for more papers by this author
  • J. Moya,

    1. Department of Basic Psychology, Clinical and Psychobiology, Faculty of Human and Social Sciences, Univerity Jaume I, Castelló, Spain
    Search for more papers by this author
  • M. I. Ibáñez,

    1. Department of Basic Psychology, Clinical and Psychobiology, Faculty of Human and Social Sciences, Univerity Jaume I, Castelló, Spain
    Search for more papers by this author
  • G. Ortet,

    1. Department of Basic Psychology, Clinical and Psychobiology, Faculty of Human and Social Sciences, Univerity Jaume I, Castelló, Spain
    Search for more papers by this author
  • C. Gastó,

    1. Centre for Biomedical Research Network on Mental Health (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
    2. Department of Psychiatry, Clinical Institute of Neurosciences, Clinical Hospital of Barcelona and Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), Barcelona, Spain
    Search for more papers by this author
  • L. Fañanás

    Corresponding author
    1. Anthropology Unit, Department of Animal Biology, Faculty of Biology, University of Barcelona, Barcelona, Spain
    2. Biomedicine Institute of the University of Barcelona (IBUB), Barcelona, Spain
    3. Centre for Biomedical Research Network on Mental Health (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
    • L. Fañanás, Anthropology Unit, Department of Animal Biology, Faculty of Biology, University of Barcelona, Av. Diagonal 645, Barcelona, 08028, Spain.

      E-mail: lfananas@ub.edu

    Search for more papers by this author

Abstract

Objective

To test whether the association between childhood abuse, cannabis use and psychotic experiences (PEs) was moderated by the COMT (catechol-O-methyltransferase) gene.

Method

Psychotic experiences (PEs), childhood abuse, cannabis use and COMT Val158Met genotypes were assessed in 533 individuals from the general population. Data were analysed hierarchically by means of multiple linear regression models.

Results

Childhood abuse showed a significant main effect on both positive (β = 0.09; SE = 0.04; P = 0.047) and negative PEs (β = 0.11; SE = 0.05; P = 0.038). A significant three-way interaction effect was found among childhood abuse, cannabis use and the COMT gene on positive PEs (β = −0.30; SE = 0.11; P = 0.006). This result suggests that COMT genotypes and cannabis use only influenced PE scores among individuals exposed to childhood abuse. Furthermore, exposure to childhood abuse and cannabis use increased PE scores in Val carriers. However, in individuals exposed to childhood abuse but who did not use cannabis, PEs increased as a function of the Met allele copies of the COMT gene.

Conclusion

Cannabis use after exposure to childhood abuse may have opposite effects on the risk of PEs, depending on the COMT genotypes providing evidence for a qualitative interaction. Val carriers exposed to childhood abuse are vulnerable to the psychosis-inducing effects of cannabis.

Ancillary