Background: Additive interaction between childhood trauma and cannabisuse in increasing risk for psychotic disorders has been recently demonstratedin a prospective (Harley et al., 2009) and a cross sectional study(Konigs et al., 2011), although not replicated in another survey (Kuepperet al., 2011). This study aimed to analyse additive interaction betweenlifetime cannabis and severe child abuse in increasing the risk for psychosisin a sample of first episode psychosis patients and geographically matchedcontrols. In addition, analyses were re-run separately for males and femalesin order to investigate whether the association was moderated by gender.Methods: The sample consisted of 231 patients with psychosis at theirfirst admission to the South London and Maudsley Mental Health NHSFoundation Trust, and 214 controls. Severe childhood trauma was assessedusing the Childhood Experience of Care and Abuse Questionnaire (Bifulcoet al., 2005) and it was defined as history of any physical abuse involvinginjuries or any sexual abuse involving intercourse which occurred beforeage of 17 years. Lifetime cannabis use was assessed using the CannabisExperience Questionnaire modified version (Di Forti et al., 2010).Results: Controlling for ethnicity, level of education, and psychiatric familyhistory, both childhood abuse (Adj OR1.87, 95%CI 1.08-3.21) and lifetimecannabis use (Adj OR 1.89, 95%CI 1.18-3.00) were associated with an increasedrisk for psychosis. Moreover, the joint effect of early trauma andcannabis use (Adj OR 3.82, 95%CI 1.79-8.14) was higher than the effectof either variable alone, suggesting an additive interaction between them.Although cannabis × trauma interaction was observed both in males andfemales, the effect appeared stronger in the latter group.Discussion: Our findings support the previous literature about an additiveinteraction between childhood trauma and cannabis use in increasing riskfor psychosis.
|Numero di pagine||1|
|Stato di pubblicazione||Published - 2012|