What Do Four Decades of Research Tell Us About the Association between Childhood Adversity and Psychosis: an Updated and Extended Multi-level Meta-analysis

Objective Estimating the current association between childhood adversity and the risk of psychosis is crucial for prevention and intervention. We provided an updated synthesis of evidence from the past four decades, and expanded the available data by investigating a broad array of adversity subtypes, and exploring sex differences and the age of psychosis onset as relevant factors.

Methods We searched PubMed, EMBASE, PsycINFO, Web of Science, WANFANG,
and CNKI, for case-control, cross-sectional and cohort studies on the association
between adversity and psychotic symptoms/illness. Multi-level meta-analysis,
prediction intervals calculation, and sensitivity analyses were conducted.

Results The main analysis included 183 study samples (N=349,265), with 119 casecontrol studies (15,186 cases; 14,879 controls), 51 cross-sectional studies (N=299,659), and 13 cohort studies (N=19,541). Significant associations between adversity and psychosis were observed across all study designs, yielding an overall OR of 2.80 (2.18–3.60). Secondary analyses revealed that exposure to each adversity subtype increased the odds of psychosis, with the highest OR of 3.54 (3.04–4.13) for emotional abuse, and the lowest OR of 1.58 (1.48–1.68) for parental antipathy. No statistically significant sex differences were observed, although the OR for sexual abuse was higher for women. Onset of psychosis was earlier in adversity-exposed individuals (mean difference=-0.79 years, 95%CI -1.47 to -0.12).

Conclusions This is the largest meta-analysis to date on the association between
childhood adversity and psychosis. The results have broad clinical implications, as they highlight the need for selective prevention of exposure to early adversities and the implementation of trauma-informed therapies in the treatment of psychosis.