Psycho-biological mechanisms involved in suicidal risk, suicide attempts, and aggression: A replication and extension in bipolar disorder

Background: Despite studies showing the individual roles of childhood maltreatment, alexithymia, impulsivity, and biological markers in suicide and aggression in bipolar disorder (BD), combined influence of these factors has not been studied yet. Methods: This study aimed to explore this issue in 353 individuals with BD completing self-report and clinicianrated measures. Blood samples were also taken to evaluate biological markers. Results: Higher C-reactive protein (CRP) and triglycerides (TG) and lower total cholesterol (TC) were observed in alexithymic people. Individuals with childhood maltreatment showed elevated CRP and lower TC and highdensity lipoprotein cholesterol (HDL-C). Those with both alexithymia and maltreatment displayed the most adverse profile regarding CRP and lipids. Depressive and manic symptoms, suicidal ideation, and low TC and HDL-C were associated with suicide attempts, while age, depressive and manic symptoms, childhood maltreatment, alexithymia, impulsivity, CRP, and low HDL-C accounted for suicidal risk. Aggression was linked to gender, impulsivity, and reduced low-density lipoprotein cholesterol (LDL-C). Limitations: A cross-sectional design is a limitation of the study. Conclusion: The study underscores the relationships between psychological and altered biomarkers, particularly elevated CRP and decreased lipid levels, and their roles in contributing to suicide and aggression, proposing a psychobiological model in BD.