The Association Of Stressful Life Events And Suicidal Behavior Among Adolescents In Shandong Province

1.BackgroundAdolescent suicide is a serious public health across the world.It is the fourth leading death among adolescents,leading to several hundred thousand adolescents death every year,which might bring serious chain reactions to individuals,others and society.Suicidal behavior is a series of dynamic and continuous complex behaviors,among which non-fatal suicidal behavior is the important predictor of suicide death.Non-fatal suicidal behavior(suicidal behavior referred to in this study)including suicidal ideation,suicide plan and suicide attempt,is more common and the prevalence rate is higher among adolescents.A global survey indicated that 13.6%of adolescents reported having past-year suicidal ideation and 10.2%reported past-year suicide attempt,and 10%suicide attempters would die by suicide.Hence,committing research about adolescent suicidal behavior is of great significance to prevent adolescent suicide and supplement the suicide intervention strategies.Adolescent suicide crisis might be due to the failed stress response,and the combination or cumulation of various stressors would increase the risk of suicidal behavior.Stressful life events(SLE)refer to various stressful stimuli experienced by individuals in regular social life;as a kind of important stressor,they could trigger psychological and behavior problems,and in severe cases,individuals might commit suicide-a specific stress response-to escape.The SLE that adolescents might experience include family discord,academic stress,interpersonal tension,financial hard,love frustration and so on,which might cause stress-related problems in adolescents who are at a sensitive time to develop a stress response.Although the association between SLE and suicidal behavior has been extensively studied,it was limited to cross-sectional studies and the conclusion was not consistent.What else,SLE might increase the suicide risk though the accumulation and superposition,but the concrete relationship between them was not clear.And few studies have looked for the specific events most related with suicidal behavior using longitudinal data.Therefore,the aim of this study was to further explore the association of SLE and suicidal behavior using the cohort study.2.AimsUsing the data from Shandong Adolescent Behavior and Health Cohort(SABHC),this study aimed to know about the occurrence of suicidal behavior and SLE among adolescents in Shandong Province and describe their basic information and the changing trend of three years;to testify the association between SLE with suicide behavior(including suicidal ideation,suicide plan and suicide attempt)and find the life events that had significant impact on suicidal behavior;to explore whether there exists a dose-response relationship between SLE and suicidal behavior among Chinese adolescents.3.Methods3.1 SubjectsThe population of this study came from the SABHC,which is a three-year follow-up study about adolescent health and behavior condition in Shandong Province.After considering social demography characteristics,the behalf of region adolescent students,the cooperation basis before and the convenience of follow-up,three senior high schools and five junior high schools were selected to carry out this study.The basic information was collected in 2015,and the follow-up information was collected at the same month in 2016 and 2017,respectively.The sample selected for this study was Grade 7 and Grade 10 who participated in three surveys.Totally,6995 adolescents participated in the baseline survey in 2015,with 5807 adolescents followed up in 2016 and 4614 adolescents in 2017.3.2 MeasurementsThis study was conducted by a self-reported questionnaire.The Adolescent Health Questionnaire(AHQ)was used to investigate the demographic information and health status of adolescents.All surveys were completed by students during normal class hours under the guidance of trained professionals,and participants were asked to scan the instructions carefully before filling out,and were told to complete the questionnaire voluntarily and anonymously.This study was approved by the Ethics Committee of Preventive Medicine,Shandong University.The informed consent of the target class participants and their parents and the permission of the target schools were also obtained before the formal launch.3.3 ContentsThe AHQ includes basic personal information,general health status,mental health problems,family situation,stressful life events and so on.Among them,suicidal behavior is measured by the related items of adolescents’ suicidal behavior in the past year,including suicidal ideation,suicide plan and suicide attempt.Stressful life events were measured by revised edition of Adolescent Self-Rating Life Events Checklist(ASLEC)to assess the daily life stress events of adolescents and they were divided into three categories:the low,moderate and high level.Depression score was assessed according to the Center for Epidemiologic Studies Depression Scale(CES-D)and other information,such as sex,age,ever smoking and ever drinking,was obtained using relevant self-compiled items.3.4 Statistical analysisSPSS24.0(online edition)and Stata15.1 were used for data processing and statistical analysis in this study.Basic difference comparison was described using χ2 test,t test,variance analysis and rank sum test.Logistic regression analysis was used to analysis the relationship between SLE and adolescent suicidal behavior using baseline data.Follow-up data were analyzed using Generalized Estimation Equation(GEE)model to further explore the relationship between them,and LASSO regression was used to screen for life events that had significant impact on suicidal behavior.Then,Restricted Cubic Spline(RCS)model was used to fit the dose-response relationship between SLE and suicidal behavior.4.Results4.1 The basic characteristics of adolescent suicidal behaviorIn three surveys,the prevalence of past-year suicidal ideation was 12.39%in 2015,9.40%in 2016 and 9.15%in 2017,respectively;the prevalence of past-year suicide plan was 3.35%in 2015,3.43%in 2016 and 3.12%in 2017,respectively;the prevalence of past-year suicide plan was 1.59%in 2015,2.43%in 2016 and 2.10%in 2017,respectively.Across the threesurvey time point,suicidal ideation prevalence displayed a decreasing trend(Trend χ2=35.43,P<0.001),and suicide plan prevalence maintained relatively stable(χ2=0.79,P=0.674),and the suicide attempt prevalence showed a fluctuating state(χ2=11.74,P=0.003).4.2 The characteristics of adolescent stressful life eventsIn three surveys,the M(P25,P75)of SLE-number were 15(8,23),11(4,21),and 8(2,17)respectively,and the M(P25,P75)of SLE-intensity were 64(55,78),60(52,74)and 56(50,67),respectively;in different categories of SLE,the proportion of the low level of SLE-number(Trend χ2=482.12,P<0.001)and SLE-intensity(Trend χ2=413.69,P<0.001)increased,and the moderate and high level decreased by year.The highest frequency events of SLE were "Parents held very high academic expectations of you"(79.00%in 2015),"You failed an important exam/interview"(57.67%in 2016),and"You felt pressured to enter university or a better school"(53.68%in 201 7)respectively in three surveys.4.3 The association between stressful life events and suicidal behaviorAt baseline,the median of SLE-number and SLE-intensity in adolescents with suicidal ideation,suicide plan or suicide attempt were higher than those without,and the differences were statistically significant except for the relationship between SLE-number and suicide attempt(Ps<0.01).The results in 2016 and 2017 were consistent with results at baseline,and all differences were statistically significant(Ps<0.01).Based on the baseline data,the results showed that in the univariate model,both moderate and high levels of SLE-number and SLE-intensity were associated with suicidal ideation and suicide plan,and only high level of SLE-number and high level of SLE-intensity were associated with suicide attempt compared with low level(Ps<0.05).After adjustment for demographic information and depression score,only high level of SLE-number(OR=1.39,95%CI=1.14-1.69)and moderate level(OR=1.50,95%CI=1.22-1.85)and high level of SLEintensity(OR=1.54,95%CI=1.25-1.89)were associated with increased risk of suicidal ideation with a stable statistical testing ability;when SLE-number and SLE-intensity were both included,only the effect of SLE-intensity on suicidal ideation were statistically significant(Ps<0.01).Besides,similar univariate model results of SLE-number and SLE-intensity and suicidal behavior were shown in GEE model with follow-up data and in Logistic model with baseline data.After adjustment for demographic information and depression score,only high level of SLE-number(OR=1.27,95%CI=1.11-1.46)and moderate level(OR=1.27,95%CI=1.12-1.45)and high level of SLE-intensity(OR=1.31,95%CI=1.14-1.51)were associated with increased risk of suicidal ideation;when SLE-number and SLE-intensity were both included,it was found that only the moderate level of SLE-intensity had a statistically significant relationship with suicidal ideation(OR=1.29,95%CI=1.10-1.52).Among SLE,the occurrence of tension with parents and love frustration were associated with increased risk of suicidal ideation,suicide plan and suicide attempt(Ps<0.05);and only some impact of tension with parents(OR=1.25,95%CI=1.08-1.46)and a lot of impact of love frustration(OR=1.37,95%CI=1.10-1.71)were associated with increased risk of suicidal ideation,and some impact of tension with parents(OR=1.46,95%CI=1.13-1.89)and extremely high impact of love frustration(OR=1.38,95%CI=1.10-1.89)were associated with increased risk of suicide plan,but only some impact of tension with parents(OR=1.47,95%CI=1.05-2.07)showed statistically significance in the association with suicide attempt.Also in this study,after adjusting for the covariates,the moderate level of SLE-number(OR=0.40,95%CI-0.22-0.71)and moderate level of SLE-intensity(OR=0.46,95%CI=0.260.83)were associated with decreased risk of suicide attempt at baseline;the moderate level of SLE-number(OR=0.67,95%CI=0.49-0.92)was associated with decreased risk of suicide attempt at follow-up;and among SLE,the occurrence and some impact of the events-pressure about entering a higher school and being talked privately and spread rumors-also might be associated with decreased risk of suicide attempt(Ps<0.05).In addition,this study further explored the dose-response relationship between SLE and suicidal behavior.The results showed a non-linear trend of first decreasing and then increasing,with a S-shaped curve between SLE and suicidal ideation,and a J-shaped curve between SLE and suicide plan or suicide attempt;a certain degree of SLE had a possible protective effect on suicidal behavior,although not all relationship might be statistically significant.5.Conclusions(1)Across three surveys,the prevalence of suicidal ideation decreased gradually,with suicide plan being relatively stable and suicide attempt fluctuating.(2)The overall SLE-number and SLE-intensity of adolescents decreased gradually.In all SLE measured here,academic related events reported highest frequency among adolescents in Shandong Province.(3)Stressful life events were associated with suicidal behavior,mainly with increased risk of suicidal ideation,and while to some extent,moderate level of SLE might be associated with decreased risk of suicide attempt.However,the relationships were non-linear and generally represented a trend of decreasing first and then increasing.(4)Although academic related events were the most frequent,consistently,tension with parental and love frustration had the significant influence on the increased risk of suicidal behavior among adolescents in China.