The Impact of Childhood Maltreatment on the Bipolar Disorder Course and Prognosis: A Systematic Review and Meta-Analysis.

INTRODUCTION This systematic review and meta-analysis aims to examine the relationship between childhood maltreatment and the course and prognosis of bipolar disorder and to compare clinical symptomatology between patients with and without a history of such maltreatment.

Method

The recommended Preferred Reporting Items for Systematic Reviews and Meta-Analyses: The PRISMA Statement guidelines were followed. PubMed, Scopus, Web of Science and PsycInfo databases were searched from 1 September 2016 to 31 January 2025. In addition, studies identified through two previous reviews were also evaluated for inclusion. A meta-analysis of standardized mean differences was conducted using Hedges' g as the effect size index to compare the severity of clinical symptomatology between individuals with and without a history of childhood maltreatment.

Results

Twenty-seven studies identified through the database searches and 23 studies identified from previous reviews were included in the present review. The included studies showed that patients who had been exposed to some form of childhood maltreatment exhibited a worse course and prognosis of bipolar disorder across various variables. A random-effects meta-analysis was conducted using 17 effect sizes extracted from eight primary studies. The pooled effect size was small but statistically significant (Hedges' g = 0.19), indicating greater symptom severity among patients with a history of childhood maltreatment. Separate analyses by symptom domain showed significant effects for depressive and psychotic symptomatology.

Conclusion

A history of childhood maltreatment worsens the course and prognosis of bipolar disorder. Therefore, clinicians should consider this relationship when planning and administering treatment.