Childhood maltreatment and cognitive functioning in bipolar disorder: A systematic review and meta-analysis

Aims: Characterising the association between childhood maltreatment (CM) and cognitive functioning in bipolar disorder (BD) is crucial for improving the understanding of how early environmental risk factors impact the presentation of the disorder. We conducted a systematic review and meta-analysis to estimate associations between overall and subtypes of CM, global cognition/IQ, and five cognitive domains in BD (attention/processing speed, verbal memory/learning, working memory, executive functions/verbal fluency, and social cognition), and to explore moderators/mediators in these associations. Methods: A systematic search was performed on 24 June 2024 to identify published peer-reviewed articles in six databases (PROSPERO-CRD42023468641). Results: From 780 identified records, 20 studies were included, comprising 2457 individuals with BD (M ± SD, age in years = 39.5 ± 9.7; 41.3% males; BD type I = 81.2%); 152 effect sizes were pooled in random-effect meta-analyses. Overall CM was negatively associated with global cognition/IQ, attention/processing speed, and verbal memory/learning (r = −0.14 to −0.18, p = 0.002 to < 0.001). Sexual/physical abuse and physical neglect were negatively associated with global cognition/IQ, working memory, and executive functions/verbal fluency (r = −0.07 to −0.18, p = 0.037 to < 0.001). Emotional abuse was negatively associated with working memory (r = −0.12, p = 0.002). Emotional neglect was unrelated to cognitive functions. CM (overall/subtypes) was unrelated to social cognition. Meta-regressions did not identify any consistent moderators. Narrative synthesis identified possible moderators/mediators. Associations were of small magnitude, and a limited number of studies assessing CM subtypes and cognitive functions are available. Conclusion: CM exposure is associated with worse cognitive performance in people with BD, an effect observed across multiple maltreatment types and cognitive domains. Besides trauma-informed interventions, those with BD and CM require cognitive assessment and therapies to rehabilitate cognitive functioning.