“Novel interventions that aim to address how trauma affects the mechanisms underlying the development of psychotic experiences could improve mental health outcomes,” wrote Jazz Croft, M.Sc., of the University of Bristol, United Kingdom, and colleagues.
Croft and colleagues analyzed data from the Avon Longitudinal Study of Parents and Children, a large population-based birth cohort in the United Kingdom of women who had an expected delivery date between April 1, 1991, and December 31, 1992. The total sample comprised 14,775 live births.
Exposure to traumatic events in early childhood (0 to 4.9 years), middle childhood (5 to 10.9 years), or adolescence (11 to 17 years) was determined by the responses of participants or their parents to 121 questions about traumatic events. When the participants were age 12 and 18, they were asked about psychotic experiences using the psychosis-like symptoms semi-structured interview (PLIKSi). The PLIKSi questions assessed the presence of 12 psychotic experiences, including hallucinations, delusions, and experiences of thought interference.
In those with psychotic experiences at age 18 years, 83.8% reported exposure to trauma compared with 62.6% without psychotic experiences. Children with any exposure to trauma before age 17 were slightly more than three times as likely as those without trauma exposure to have psychotic experiences by age 18, according to the study.
Moreover, there appears to be a dose-response relationship between trauma and psychosis. Exposure to three or more types of trauma by the age of 17 was associated with a 4.7-fold increase in the odds of having psychotic experiences. Additionally, exposure to trauma during early and middle childhood as well as adolescence was associated with a higher risk of developing psychotic experiences than exposure within only one or two of these periods.
“This study indicates that, assuming the association is accurate and causal, a substantial proportion of participants would not have developed psychotic experiences if they had not been exposed to traumatic experiences during childhood,” the researchers wrote.
For related information, see the Psychiatric News article “CBT For Ultra-High Risk Patients Lowers Risk for Psychosis” and the American Journal of Psychiatry article “Childhood Trauma and Psychosis in a Prospective Cohort Study: Cause, Effect, and Directionality.”