Relationship Of Depressive And Anxiety Symptoms With Non-Suicidal Self-Injury And Suicidal Attempt Among Chinese Adolescents:The Mediation Role Of Sleep Quality

Background:Adolescence is a critical period in the process of growth and development.During this period,adolescents have a high incidence of mental illness and risk behavior problems.Non-suicidal self-injury（NSSI）and Suicide attempt（SA）in adolescents have become public health issues of concern worldwide.It is necessary to further explore the risk factors of NSSI and SA in adolescents and the complex interactions between known risk factors.In previous studies,depressive symptoms and anxiety symptoms are generally considered to be significant risk factors of NSSI and SA,but some studies have found inconsistent associations,and there is a lack of longitudinal design studies to explore the causal relationship and related mechanisms.Objective:To explore the causal relationship of depressive symptoms and anxiety symptoms with NSSI and SA in adolescents,and to examine the mediating effect of poor sleep quality on these relationships.Methods:This study was a cohort study design.We used the Chinese Adolescent Health Growth Cohort（CAHGC）build in Hengyang,Zhongshan,and Shenzhen,China.The general demographic data,social support,emotional management ability,depressive symptoms,anxiety symptoms,sleep status,NSSI,SA behaviors and other information were collected at baseline survey（T1）and the first-year follow-up survey（T2）one year later by using the Chinese Adolescents’Physical and Mental Health Questionnaire.SPSS 25.0 software and Mplus 8.3 software were used for statistical analysis.Non-conditional binary logistic regression model was used analyze the associations between depressive and anxiety symptoms with NSSI and SA.A Cross-lagged Panel Model（CLPM）was constructed to test the causal relationship between variables,and a semi-longitudinal mediation model was constructed to explore the mediating effect of poor sleep quality.Results:1.A total of 1771 valid questionnaires were collected at T1 and included in this study,including 994（56.1%）boys and 777（43.9%）girls.454（25.6%）from Hengyang,243（13.7%）from Shenzhen and 1074（60.6%）from Zhongshan were recruited.The age ranged from 11 to 16 years,with an average age of 12.9±0.6 years.A total of 1590 valid questionnaires were collected at T2,and the loss rate was 10.2%.At T1,the prevalence of depressive symptoms and anxiety symptoms was 20.2%and30.9%,the incidence of NSSI and SA in the past 12 months was 17.1%and 8.3%.At T2,the prevalence of depressive symptoms and anxiety symptoms was 19.0%and26.7%,the incidence of NSSI and SA in the past 12 months was 10.3%and 2.8%,respectively.2.Multivariate logistic regression analysis of baseline data showed that depressive symptoms（a OR=1.89,95%CI=1.34-2.65）and anxiety symptoms（a OR=2.84,95%CI=2.05-3.94）were independently associated not only with NSSI but also with SA（depressive symptoms:a OR=3.20,95%CI=2.03-5.05;anxiety symptoms:a OR=2.98,95%CI=1.84-4.84）.3.A cross-lag model was constructed for the two periods of data,and the results showed that the path T1 NSSI→T2 depressive symptoms was significant（β=0.095,P=0.002）,but the path T1 depressive symptoms→T2 NSSI was not significant（β=0.064,P=0.054）;The path T1 anxiety symptoms→T2 NSSI（β=0.080,P=0.005）and T1 NSSI→T2 anxiety symptoms（β=0.073,P=0.013）were significant;The path T1 depressive symptoms→T2 SA was significant（β=0.098,P=0.003）,but the path T1 SA→T2depressive symptoms was not significant（β=0.050,P=0.112）;There was no significant difference in the path T1 anxiety symptoms→T2 SA（β=0.057,P=0.059）and T1SA→T2 anxiety symptoms（β=0.022,P=0.437）.4.Mediation analysis showed that the indirect effect path T1 NSSI→T2 poor sleep quality→T2 depressive symptoms was significant(β_ab=0.020,P=0.040),and the mediation ratio was 19.7%.The indirect effect path T1 anxiety symptoms→T2 poor sleep quality→T2 NSSI was significant(β_ab=0.015,P=0.001),with a mediation ratio of 32.2%.The indirect effect path T1 NSSI→T2 poor sleep quality→T2 anxiety symptoms was significant(β_ab=0.023,P=0.040),and the mediation ratio was 25.4%.The indirect effect path T1 depressive symptoms→T2 poor sleep quality→T2 SA was significant(β_ab=0.007,P=0.003),with a mediation ratio of 19.2%.Conclusions:1.In the general population of adolescents in China,NSSI behavior increases the risk of depressive symptoms and anxiety symptoms at one year,anxiety symptoms increase the risk of NSSI behavior at one year,and depression symptoms increase the risk of SA behavior at one year.2.Poor sleep quality partially mediates the effect of NSSI on depressive symptoms and anxiety symptoms,the effect of anxiety symptoms on NSSI,and the effect of depression symptoms on SA in adolescents.