Childhood adversity and hallucinations: a community-based study using the National Comorbidity Survey Replication

Numerous studies of both clinical and large-scale population based samples have demonstrated that adverse childhood events are risk factors for subsequent psychosis. This study assessed the relationships between adverse childhood events and auditory and visual hallucinatory experiences.

The study analysed data from the National Comorbidity Survey Replication conducted in the US that assessed (all before age 16) rape, sexual assault and physical assault. Psychosis symptomatology was represented by lifetime experience of auditory and visual hallucinations. Control variables included gender, age, urbanity, ethnicity, marital status, education, employment status, alcohol dependence and drug dependence.

All three adverse events were significantly related to both types of hallucinations. Those who had been raped as children were 3.3 times more likely to have experienced visual hallucinations and 3.5 times more likely to have experienced auditory hallucinations compared to those who had not been raped in childhood. Both rape and physical assault significantly predicted visual and auditory hallucinations. A significant dose-response relationship was also found.

Previous findings indicating that adverse events in childhood may be causally related to subsequent psychosis are supported. The psychological and biological mechanisms underlying the relationship are already the subject of investigation. Repeated recommendations concerning routine enquiry about adverse experiences in childhood in order to facilitate comprehensive formulations and appropriate treatment, also receive support from these findings.