Abstract:

Objective To explore the relationship between suicidal/self⁃injury behaviors and the levels of inflammatory cytokines in adolescents with affective disorder. Methods Seventy ⁃eight adolescents with affective disorder aged 15 ~ 24，who met the current diagnostic criteria of major depressive episode and major depressive episode of DSM⁃5 bipolar disorder were included in the study，26 of them in the non⁃suicidal/self⁃injury group and 52 in the suicidal/self ⁃ injury group. Their clinical symptoms were assessed by the Hamilton Depression Scale （HAMD），Hamilton Anxiety Scale（HAHA）and 32⁃item hypomania symptom Checklist（HCL⁃32）. Fasting venous blood was collected in the next morning following admission，and the levels of inflammatory cytokines in the samples were determined by ELISA. Results In the suicidal/self ⁃injury behavior group，the number of female （75.00%）was significantly higher than the number of male（25.00%）（χ2 = 4.875；P = 0.027）. The mean age in the suicidal/self⁃injury behavior group was significantly lower than that in the non⁃suicidal/self⁃injury behavior group ［（16.73 ± 2.09）vs.（18.69 ± 2.46），t = 3.683；P < 0.001］. The expression levels of IL⁃4 and IL⁃13 in the anti⁃ inflammatory cytokines in the former were significantly lower than those in the latter（F = 9.261，P = 0.003；F = 4.462，P = 0.038，respectively）. By binomial logistic regression analysis，the risk factors for the patients with suicidal/self⁃injury behavior were age（OR = 0.504），female（OR = 9.141），bipolar Ⅱ（OR = 3.235），IL⁃4（OR = 0.964），and IL⁃13（OR = 0.952）. Conclusion Bipolar Ⅱ ，female，younger age and significantly decreased expression of IL⁃4 and IL⁃13 are independent risk factors for suicidal/self⁃injury behavior in adolescents with affec⁃ tive disorder. 

Key words:

affective disorder, suicide, self?injury, inflammatory cytokines, IL?4, adolescents