Childhood trauma was correlated with cannabis use in schizophrenia patients, but no significant interaction between the two factors was found, based on data from 366 individuals, including 295 with schizophrenia and 71 with schizoaffective disorder.

“Childhood trauma and cannabis consumption are among the most studied environmental risk factors for schizophrenia and are also considered to be risk-modifying factors,” wrote Grégoire Baudin of Université François-Rabelais in Tours, France, and colleagues (Schizophr Res. 2016;175:161-7).

To examine the relationship between CT and cannabis use in schizophrenia, the researchers assessed patients aged 15-84 years using several tools, including the Global Assessment of Functioning Scale , the Positive and Negative Symptoms Scale , and the Childhood Trauma Questionnaire .

Overall, the proportion of patients with a history of childhood trauma (CT) was not significantly different in those with and without cannabis use disorders, the researchers reported. However, CT was a significant predictor of the number of hospitalizations and of high scores on measures of excitement and emotional distress, and poor levels of function and quality of life.

The study was limited by not being representative of the schizophrenia population as a whole, the researchers noted. However, “our results emphasize the need for clinicians to systematically inquire about the traumatic history of patients with psychotic disorders, and consider trauma-focused therapy” for people with schizophrenia and for people at risk, the investigators added.

The researchers had no financial conflicts to disclose. The study was funded in part by the FondaMental Foundation, INSERM, and Investissements d’Avenir programs. Mr. Baudin has received a research grant from the FondaMental Foundation.

Find the full study here: doi: 10.1016/j.schres.2016.04.042 .