Distinctions in theory of mind (ToM) and serum chemokine profiles between adolescent patients with depressive disorder with suicidal attempt and non-suicidal counterparts: A case-control study.

BACKGROUND

Substantial evidence suggests an association between suicide-related behaviors in patients with depressive disorders and impaired social cognitive functioning and immune dysfunction.This study aims to identify the characteristics of adolescents with depressive disorders who have attempted suicide from social cognitive and immune perspectives and to explore potential risk factors for suicidal attempts.

METHODS

This study included 166 adolescents with depressive disorders, who were divided into a suicide attempt group (SA, 86 cases) and a non-suicide attempt group (NSA, 80 cases) based on the presence or absence of suicide attempt behavior, along with 23 healthy controls (HC). Social cognition was assessed using the Theory of Mind Story Picture Task, and serum chemokines were detected using the Meso Scale Discovery (MSD) electrochemiluminescence (ECL) detection technique.

RESULTS

Regarding ToM, the SA group showed higher scores in comprehension of deception than the NSA group (p = 0.017); the NSA group had lower scores in sense of reality, personal detection of deception, and total ToM than the HC group (all p < 0.05). For chemokines, the SA group had lower Eotaxin-2 levels than the HC group (p = 0.003), and the NSA group exhibited significantly lower levels of Eotaxin, Eotaxin-2, Eotaxin-3, and MCP-1 than the SA group (all p < 0.05). The regression model (R²=0.268) indicated that comprehension of deception (β=0.85, OR=2.34, p = 0.045), MINI score (β=0.09, OR=1.10, p < 0.001), and serum Eotaxin level (β=0.02, OR=1.02, p < 0.001) were independent risk factors for suicidal attempts. Specifically, enhanced comprehension of deception (a core ToM component) and elevated Eotaxin levels were positively associated with suicidal behavior in adolescent depressive patients.

CONCLUSION

Assessing social cognition, particularly the comprehension of deception through Theory of Mind evaluations, contributes to a better understanding and identification of suicidal behaviors. Moreover, elevated serum Eotaxin levels serve as a significant risk factor for suicidal behavior in adolescents with depressive disorders.