Self-report questionnaires on the presence of psychosis-like experiences, prior traumatic events, and sleep problems were completed by 409 participants in Baltimore County, Maryland. The Prodromal Questionnaire-Brief was used to examine the presence or absence of attenuated symptoms of psychosis. The General Trauma Questionnaire-Revised was used to quantify trauma, and the Iowa Sleep Disturbances Inventory was used to measure sleep habits.
The sample was 50.6% women, and of an average age of 20.10 years (standard deviation, 3.22 years). Three sets of predictors were then entered into a hierarchical multiple regression model: sociodemographic, psychosocial (including trauma), and sleep.
Of the cohort, 48.7% reported at least 1 previous traumatic experience and 81.5% endorsed at least 1 item of the prodromal questionnaire. At least 1 sleep problem was reported by every participant, most commonly nightmares (96.0%), night anxiety (89.4%), and nonrestorative sleep (85.8%).
Previous traumatic experiences were significantly correlated with both psychosis-like experiences (P <.001) and sleep dysfunction (P <.001). Sleep dysfunction was significantly correlated with the presence of psychosis-like experiences (P <.001). Specific traumas associated with psychosis-like experiences included: experiencing a life-threatening event; involvement in a fire, flood, or natural disaster; the experience of shock resulting from a traumatic event happening to someone close; or other. Sleep dysfunction was also correlated with these same 4 specific traumas, along with witnessing someone being injured or killed and sexual molestation.
Per the hierarchical regression analysis, sleep disturbances predicted psychosis-like experiences at an additional increment of variance above psychosocial variables. In the final model, nightmares, fragmented sleep, and depressive symptoms all uniquely predicted psychosis-like experiences. However, previous trauma exposure was no longer a significant predictor once sleep subscales were included (P =.085).
These findings build on the literature indicating a strong correlation among trauma, disrupted sleep, and psychosis-like experiences. Such data may be helpful in developing treatment strategies for patients with past trauma and sleep disturbances to attenuate the possibility of future psychosis-like experiences.
Andorko, ND, Millman ZB, Klingaman E, et al. Association between sleep, childhood trauma and psychosis-like experiences [published online March 8, 2018]. Schizophr Res. doi: 10.1016/j.schres.2018.02.052.