Psychological Medicine
May 4, 2023
G. Trotta, Victoria Rodriguez, D. Quattrone et al.
Childhood adversity and cannabis use are both known risk factors for psychosis. This study examined whether cannabis use might explain the link between childhood adversity and psychotic disorders. Data from 881 first-episode psychosis patients and 1231 controls from the EU-GEI study showed that household discord was associated with psychosis partly through cannabis use. Lifetime cannabis use mediated 17% of the association, cannabis potency mediated 14%, and frequency of use mediated 29%. Similar results appeared for early exposure to household discord. The findings suggest that harmful cannabis use patterns partially explain how household discord leads to psychosis, and children exposed to challenging home environments could benefit from interventions to prevent cannabis misuse.
Translational Psychiatry
August 10, 2021
D. Quattrone, U. Reininghaus, A. Richards et al.
Genetic risk for schizophrenia and cannabis use each contribute to specific symptom patterns across psychotic disorders, not just diagnostic categories. Among 617 first-episode psychosis patients, higher schizophrenia polygenic risk scores were linked to more severe negative and positive symptoms, regardless of diagnosis. In 979 controls, the same genetic risk was associated with all dimensions of psychotic experiences. Daily or current cannabis use was tied to more positive symptoms in both patients and controls, beyond the effect of genetic risk. The findings support a dimensional view of psychosis, where genetic liability relates to symptom severity and cannabis use specifically increases positive symptoms.
Translational Psychiatry
May 12, 2020
C. Hindocha, D. Quattrone, T. Freeman et al.
Heavy cannabis use is linked to psychosis, but it is unclear which users are susceptible. This study examined whether variations in three genes—AKT1, COMT, and FAAH—affect cannabis experiences, including psychotic-like and euphoric effects. Data came from 720 participants: first-episode psychosis patients, controls, and young adult cannabis users. Psychotic-like experiences were more common in patients, while euphoric experiences were more common in young users. However, none of the genetic variations were associated with these experiences, nor did they interact with participant group. The findings contradict previous research suggesting these genes modulate cannabis's psychotogenic effects.