Association between free thyroxine and aggression: the chain mediating role of hostile attribution bias and psychological resilience.

OBJECTIVE: Serum free thyroxine (FT4) has been demonstrated to be associated with human aggression. Based on the theoretical and empirical research on hostile attribution bias and psychological resilience, this study developed a chain mediating model to investigate whether these factors mediate the relationship between serum FT4 and aggression among thyroid disease patients. METHODS: A total of 418 thyroid disease patients who met the inclusion and exclusion criteria were recruited from a general hospital in Suzhou, Jiangsu Province, China, to participate in this study and completed the self-report versions of the Buss-Perry Aggression Questionnaire (BPAQ), the Word Sentence Association Paradigm for Hostility Scale (WSAP-Hostility), and the Connor-Davidson Resilience Scale (CD-RISC10). Blood samples were collected to measure serum FT4 levels by chemiluminescence immunoassay. SPSS 32.0 was used for descriptive and inferential statistical analyses. Amos 29.0 was applied to conduct structural equation modeling to examine the chain mediating roles of hostile attribution bias and psychological resilience in the association between serum FT4 and aggression. RESULTS: Serum FT4 levels were directly associated with aggression among thyroid disease patients (β = 0.244, 95% CI [0.148, 0.334]). Serum FT4 exhibited indirect statistical associations with aggression through two independent mediating pathways of hostile attribution bias (β = 0.129, 95% CI [0.088, 0.178]) and psychological resilience (β = 0.068, 95% CI [0.038, 0.107]), as well as the chain mediating pathway of these two variables (β = 0.029, 95% CI [0.016, 0.048]). Multi-group structural equation modeling demonstrated measurement and structural invariance across sexes, with no significant differences in the path coefficients. CONCLUSION: Hostile attribution bias and psychological resilience served as mediators in the association between serum FT4 levels and aggression among thyroid disease patients. Causal inferences cannot be drawn from this cross-sectional design, and future longitudinal studies are required to extend these findings.