Risk Factors For Suicide Among Chinese Rural Young People Aged 15-34 Years

1.BackgroundSuicide is the behavior of self-destruction which can be generally categorized as completed suicide death,attempted suicide,and suicide ideation.Suicide is an important public health in China and in the world.Every year approximately 1,000,000 people die by suicide.In America,suicide is the third leading cause of death among people aged 10-24 years and the second leading cause of death among American college students.In China,according to Dr.Phillips' research,suicide rate (1995-1999) is 23.2 per 100,000 people.Suicide rate in male is 20.7/100,000 people while in female the rate is 25.9/100,000 people.Suicide rate in rural area is 27.1/100,000 people while in urban area the figure is 8.3/100,000 people.The female/male ratio is 1.25 while the rural/urban ratio is 3.27.There are two peaks in the curve of suicide rate among different ages,15-34 years old and 60-84 years old.Compared to Western countries,there are three unique characteristics in Chinese suicide:1) the female/male ratio is 1.25 while in most countries in the world more men commit suicide than women(3:1);2) the rural/urban ratio is 3.27 while in most Western countries there isn't significant difference between suicide rate in rural area and that in urban area;3) there are two peaks in the curve of suicide rate among different ages,15-34 year old and 60-84 year old.In Western countries,risk factors for suicide mainly are mental illness,suicide attempt history,physical diseases,acute or chronic interpersonal problems,stressful life events,low social-economical status,living alone,unmarried,unemployed and mental illness is the most important suicide risk factor.In the west,more than 90%of suicides suffer from one or more mental illnesses.Risk factors among different populations are dissimilar.In a study on suicide risk factors among people under the age of 35 years old,acute and severe mental disorder,chronic disorder of behavior, rootlessness,social withdrawal,chronic and recent interpersonal problems were found to be the most important suicide risk factors.In China,Phillips and his colleagues conducted a psychological autopsy study in 1995.With the help of China Center of Diseases Control and Prevention and Beijing Suicide Research and Prevention Center,researchers investigated 519 valid suicide cases and 536 deaths of accidental injuries from 23 disease surveillance points in 6 districts.After adjusted for age,gender,living location and research location,the multivariate models identified 8 suicide risk factors(in order of importance):high depression symptom score,low quality of life,high chronic stress,sever interpersonal conflict in the two days before death,a blood relative with previous suicidal behavior, and a friend or associate with previous suicidal behavior.There suicide risk factors are similar to the findings in Western countries,and suicide risk increases strikingly with exposure to multiple risk factors:none of the 265 deceased people who had fewer than two of the eight risk factors died by suicide;30%(90/299) of those with two or three risk factors,85%(320/377) with four or five risk factors died by suicide.Suicide is not caused by one single reason and it's a result of multiple risk factors.Phillips and his colleagues' suicide research discovered the epidemiological status of Chinese suicide and its risk factors.However,different populations have their unique characteristics and specific suicide prevention should be established accordingly.In China,suicide was the leading death of people 15-34 years of age and rural suicide rate is three times higher than urban rate.Thus,we chose rural area as our research site,investigated young adults aged 15-34 years,explored risk factors for suicide,and tried to compare suicide risk factors among different populations (rural young men,rural young women,and rural young adults without mental illness).2.Objects2.1 To explore risk factors for suicide among Chinese rural young adults aged 15-34 years.2.2 To compare suicide risk factors among Chinese rural young men,rural young women,and rural young adults without mental illness.3.Methods3.1 Psychological autopsy studyIn this study we used psychological autopsy study to explore risk factors for suicide among Chinese rural young people.Psychological autopsy study was developed in 1950s by Suicide Prevention Center in Los Angeles to improve accuracy of coroners.Psychological autopsy study is way to disclose the suicide reason from biological,psychological,and social aspect by interviewing informants of suicides. Psychological autopsy study is a good and popular method in suicide research with high reliability and validity.3.2 Study populationWe chose Liaoning Province,Hunan Province and Shandong Province as our research sites.Six counties in Liaoning,five counties in Hunan,and five counties in Shandong were randomly selected as sampling sites.In each county,we had a project coordinator in charge of the surveillance and report of the suicide cases.Suicide cases were selected consecutively from the suicides which happened from October 2005 to June 2008 and aged 15-34 years.Before this study,we trained the village doctors how to identify and report suicide cases to the county level Center for Disease Control and Prevention which monthly reported the suicide cases to the principal investigator in each province.When the number of suicide cases accumulated to a certain number, the research team went to research sites and interviewed the informants.For each suicide case,we randomly selected one normal community control from the same area aged between 15 to 34 years.3.3 InstrumentsQuestionnaires include in our study are:3.3.1 General information:gender,age,living location,race,education level, marital status,living along or not,family size,employment status,family annual income,religion,physical diseases,family suicide history,and family mental illness history.3.3.2 Semi-structured interview for informant about suicide:suicide time,suicide site,suicide method,things happened before and after suicide,and aspirations of the suicide people.3.3.3 Psychiatric and psychological questionnaires:Suicide Intent Scale,Strain Theory Scale,Beck Hopelessness Scale,Life Event Scale,Social Support Inventory, Dickman Impulsivity Inventory,Coping Resources Inventory,State-Trait Anxiety Inventory,Hamilton Rating Scale for Depression,Structured Clinical Interview for DSM-IV,Scale for Suicide Ideation,and Center for Epidemiological Studies Depression Scale.3.4.Interview procedure3.4.1 Selection of informantsFor each suicide case we had two informants who knew the suicide person well. The first informant was generally the relative of suicide and the second informant was good friend or neighbor of the suicide.For each normal community control,we had two informants and we also interviewed the control him/herself.The principals of selection of informants were the same as that for suicide cases.3.4.2 Interview timeThe face-to-face interview often happened 2-6 months after the suicide death and the birthday of the suicide was avoided as well as Chinese festivals.The informants were interviewed according to the sequence of questions in the questionnaire and each interview lasted about 2-3 hours.Most of the interviews were done in the home of the informants and the situation was not allowed the interviewers conducted the interviews in the office of village committee or in village clinics.All the interviews were finished among October 2005 to June 2008.3.4.3 Interview processWhen the research team arrived at the research site,village doctor or village officials took the interviewer to the home of the informant and introduced the interviewer to the informant.The interviewer showed their identities and introduced our study to the informant and asked the informant to sign on the informed consent. All the informants signed on the informed consent or agreed orally.Each interview was completed by one interviewer and one informant without the third person present.4.Results4.1 Multivariate Logistic regressions showed that important suicide risk factors among Chinese rural young people aged 15-34 years were mental illness (OR=16.034),high hopelessness score(OR=11.039),negative life events(OR=6.596, OR=2.629),family suicide history(OR=4.034),low positive coping score(OR=2.998) and high dysfunctional impulsivity(OR=2.335).Joining Communist Party or Communist Youth League was protective factor for suicide(OR=0.439).4.2 Multivariate Logistic regressions showed that important suicide risk factors among Chinese rural young men were mental illness(OR=26.794),high hopelessness score(OR=18.281),low education level(OR=8.776),family suicide history (OR=4.338),poor relationship with parents(OR=3.894),negative life events (OR=1.139,OR=5.552),low social support score(OR=3.501) and low positive coping score(OR=2.658).4.3 Multivariate Logistic regressions showed that important suicide risk factors among Chinese rural women were high hopelessness score(OR=14.515),mental illness(OR=11.199),negative life events(OR=6.648,OR=14.204),family suicide history(OR=5.272),low positive coping score(OR=3.641),low social support (OR=3.448),and high dysfunctional impulsivity(OR=3.182).Joining Communist Party or Communist Youth League was protective factor for suicide(OR=0.278) among Chinese rural young women.4.4 Multivariate Logistic regressions showed that important suicide risk factors among Chinese rural young adults without mental illness were high hopelessness score(OR=8.060),family suicide history(OR=3.648),negative life events(OR=3.257, OR=7.175),low positive coping score(OR=3.421),high dysfunctional impulsivity (OR=3.196),low social support(OR=3.146),low education level(OR=2.602),poor relationship with parents(OR=2.166),high value strain score(OR=2.094) and relative poverty(OR=2.009).Marriage and joining Communist Party or Communist Youth League was protective factor for suicide(OR=0.239,OR=0.444) among Chinese rural young adults without mental illness.5.Conclusions5.1 Mental illness was the most important suicide risk factor among Chinese rural young adults aged 15-34 years.Hopelessness was good predictor for suicide among this population.Education level might be correlated with positive coping score and influenced suicide with dysfunctional impulsivity.Other suicide risk factors include relative poverty,poor relationship with parents,negative life events and low social support score.Joining Communist Party or Communist Youth League was protective factor for suicide among this population.5.2 Low education level,family suicide history,negative life events,low social support score,mental illness,high hopelessness score,and low positive coping score were common suicide risk factors for Chinese rural young men and Chinese rural young men.Poor relationship with parents was important risk factor for suicide among Chinese rural young men while high dysfunctional impulsivity score was important suicide risk factor for Chinese rural young women,and joining Communist Party or Communist Youth League was protective factor for suicide among Chinese rural young women.5.3 After exclusion of the influence of mental illness,hopelessness was the most important risk factor for suicide among Chinese rural young adults without mental illness.High value strain(conflict of different value systems) was an important suicide risk factor among this population.Marriage and joining Communist Party or Communist Youth League was protective factor for suicide among Chinese rural young adults without mental illness.5.4 Suicide risk factors among different populations were unique and specific suicide prevention strategies should be established accordingly.High value strain (conflict of different value systems) had a significant influence on suicide among Chinese rural young people without mental illness and provided with a new perspective for suicide research and suicide prevention.