The Epidimeologic Characteristics and the Risk Factors for Depression in the Chinese Military Personnel: a Cross-Sectional Study
|School||Third Military Medical University|
|Keywords||Chinese Military Personnel Depression Epidimeology Risk factors Life events|
ObjectiveThe epidemiological researches of depression play an essential part in the researches onsingle diseases of mental disorder. According to the studies of global burden of disease, it isestimated that mental disorders contribute to about20%of the total burden of disease.Depression occupies the second place in the burden of disease spectrum, after chronicobstructive pulmonary diseases. It is reported the lifetime incidence of depression is about5.2%~16.2%, which has an ascendant tendency year by year. Thus, the Epidemiology and therisk factors for depression are always the hotspots of medical psychological research. Inrecent years, Not only are the patients with depression involved in the epidemologicalresearches on depression but more and more healthy people in recent years. The trends for theepidemiological researches of depression are as follows. Firstly, respondents are becominghomogenized in the aspects such as age, proffesion, educational background and so on, whichis beneficial to the targeted researches and relevant strategies-making. Secondly, the systemsof diagnosis and classfication is becoming even better, distinguishing the types of depressioninto the depressive mood, depressive symptoms and depression disorder, which can be foundin the current criteria such as ICD-10, DSM-IV or CCMD-3. At last, the current surveyinstruments are becoming more and more perfect. Psychiatrists would get much more precisedata in the diagnosis based on depression scales and structural interviews. Not only do theepidemiological researches of depression promote the people’s cognition to depression, butboost the deepening of clinical research, which provides the important theoretic foundationfor the diagnosis, the pathogenesis, prevention and cure of depression.The Chinese military personnel is a huge special occupation group. There is still noepidemiological study of depression on a large sample in our army, but only some sporadicsurveys. It was reported that the high incidence of depression was about25.2%~51.56%in some regions or special operating environment, where military personnel were engaged inorder to investigate the the cause, pathogenesis, clinical manifestations, diagnosis andtreatment, prevention and prognosis of depression. Meanwhile, the military environmentwith high risk, high complexity, high adversity, military training with high intensity andmilitary management with high closure lead to a higher risk to depression, compared to thenormal Population. It is convient to formulate corresponding prevention and treatmentmeasures of depression by our research on the epidemiological characteristics and the riskfactors of depression in the military personnel, as to relieve the symptoms of depression andreduce the occurence of depression.The Center for Epidemiologic Studies Depression Scale (CES-D) and wereemployed for a large-scale epidemiological survey and the researches on the risk factors ofdepression in the Chinese military personnel from army, navy, air force and paramilitarytroops. The aim of the study is to master the incidence, distribution of depression and itsrisk factors in the army, as well as providing the evidence of intervention, with greatlytheoretical and practical significance.Subjects and MethodsEleven thousand and four hundred participants from army, navy, air force andparamilitary troops joined the survey, among which valid subjects were10,505. This surveycovered32cities from21provinces (autonomous regions, municipalities directly under thecentral government), which included ten provincial capital cities such as Guangzhou, Chengdu,Xi’an and Lasa etc. and seventeen other cities such as Anyang, Xuzhou, Fenghua andHandan etc. On according with the theoretical ratio of soldier, sergeant and officer number(4.5:4.5:1) and that of man and woman (100:1), participants were recruited. Among the allparticipants, there were7,634participants from the land army, accounting for72.7%,1,443from the navy, accounting for13.7%,943from the air force, accounting for9%and485fromthe paramilitary troops, accounting for4.6%.10,397participants were male, accounting for99%, while108were female, accounting for1%. The ages ranged from fourteen to fifty-seven,(22.38±3.95) at average. The education background were analyzed,2,160with a junior highschool education, accounting for20.6%,5,772with a senior high school education,accounting for54.9%,2,498with a bachelor degree, accounting for23.8%, only75with amaster or PHD degree, accounting for0.7%. Questionnaire method, SPSS data analysis and AMOS path analysis were employed in researches on the incidence, overall level and riskfactors of depression in the Chineses military personnel. There were five parts in this article.One review of the literature was included to analyse the current researches on epidemologicalstudies of depression and its risk factors in Chinese and other countries’ personnels,theincidence, the overall level of depressive symptoms, risk factors, military life events andsocial support which may influence depression. And the left parts were the four researchesabout the incidence of depression and its characteristics, the overall depression level, the mainrisk factors influencing the onset of depression and establishing one path model.Results1. The incidence of depression in Chinese military personnel is18.1%(95%CI=17.4-18.8), which is lower than that in the Chinese norm (CES-D scores≥16, accountingfor33%). The incidences of mild depression, moderate depression and major depression arerespectively8.6%(95%CI=8.0-9.2),4.4%(95%CI=4.0-4.8),5.1%(95%CI=4.7-5.5).2. The incidence of depression in the male group is significantly higher than that in thefemale group (18.2%vs10.2%，χ~2=6.034, P<0.05). The incidences of depression indifferent troops are significantly different, from high to low, the land army, the navy, the airforce and the paramilitary troops, respectively (19.9%vs17.0%vs11.2%vs6.7%,χ~2=88.673, P <0.05). The incidences of depression in different grades are also significantlydifferent, from high to low, sergeant, soldier, and officer respectively (19.3%vs17.5%vs15.4%, P <0.05). The incidence of depression in the military personnel with a bachelordegree is lower than that in the personnel with a junior high school education, a senior highschool education and a master or PHD degree (16.2%vs19.8%,18.2%,18.7%, P <0.05).3. From the division of economic regions, the incidence of depression in the westernfrontal areas is significantly higher than those in the inland areas and the eastern coastalareas (23.9%vs14.7%,14.3%, χ~2=151.524, P<0.001). From the division of administrativeareas, the incidences of depression are significantly different, from high to low, Northwestarea, Southwest area, South Central area, Northeast area, North China and East China(25.2%,22.7%,19.6%,12.4%,11.5%,9.8%, χ~2=215.232, P<0.001).4. The top three prevelace rates of depression in the military personnel with differentservicetime are25.8%,24.8%and24.2%in the11th year, the9th year and the10th yearrespectively. The top three prevelace rates of depression in the military personnel with different ages are27.0%,25.4%,22.2%at the age of28,30and26respectively.5. The depression level of the Chinese military personnel is lower than that in theChinese norm（10.28±7.63vs12.30±10.39, P＜0.01）. The depression level of the femalegroup is higher than that of the male group (The mean scores of CES-D are8.03±7.44,9.94±7.45, respectively. t=7.032, P＜0.01).6. The levels of depression in varied troops are different, which are10.45±6.50,9.76±5.30,8.13±6.00,5.67±3.99for the land army, the navy, the air force and theparamilitary troops respectively from high to low scores (F=85.578, P＜0.01). The levels ofdepression in different grades are also different, officer group better than sergeant andsoldier groups (8.73±7.52vs10.43±7.61,9.74±7.25, F=26.826, P＜0.01). The levels ofdepression in different educational backgrounds are different (F=13.986，P＜0.01), thegroup with a junior high school education or a senior high school education worse than thegroup with a master or PHD degree (10.54±7.30,10.03±7.38vs9.18±7.64,9.02±8.35).7. The level of depression in the western frontal areas is significantly higher than thosein the the eastern coastal and inland areas (11.49±7.78vs8.84±7.20,9.11±6.89, F=13.986,P＜0.01). The levels of depression in the Northwest and Southwest areas are the highest(11.38±7.74,11.34±7.89, respectively), which is followed by the South Central area(10.50±7.38), the Northeast area and the North China (8.43±6.74,8.25±6.19). The level ofdepression in the East China is the lowest (7.50±6.75).8. The top three levels of depression in the military personnel with differentservicetime are different (F=9.530, P<0.01),12.04±9.17,11.9±8.50and11.34±9.03inthe11th year, the9th year and the10th year respectively. The top three levels of depressionin the military personnel with different ages are also different (F=5.098, P<0.01),12.21±8.87,11.82±9.55and11.33±7.70at the age of28,30and26respectively.9. Environmental factors (such as life events) and genetic factors, shall be the primaryfactors (OR=5.75, OR=3.57, respectively), followed by smoking, drinking and insufficientexercises (OR=1.41, OR=1.40, OR=2.98, respectively). Chronic drug use and chronicdiseases are also regarded as the risk factors (OR=2.84, OR=3.22, respectively). Specialoperating environment (eg. missile operation (OR=2.48), artillery operation (OR=1.64), tankoperation (OR=1.38), radar operation (OR=1.27), electronic warfare and communicationoperations (OR=2.11), chemical defense operations (OR=1.12)), special natrual environment (eg. tropical environment (OR=2.07), cold environment (OR=1.82), high altitude hypoxiaenvironment (OR=2.19), tunnel environment (OR=1.64)) and training injuries (OR=3.53) areall the risk factors of the occurrence of depressive symptoms in Chinese military personnel.10. The depression level of the Chinese personnel is positively related to military lifeevents, such as great employment pressure in future, heavy work, distrust of others,lovelorn, falling ill or being injured (r=0.382，P<0.01). However, it is negatively related tothe social support (r=-0.379，P<0.01).11. According to the path model between life events, social support and depression, it isfound that life events and social support have a direct influence on depression. The pathcoefficients of the model are0.58,-0.37respectively, indicating a good model fit (χ~2/df=4，P＜0.01).Conclusion1. The overall incidence and level of depression in the Chinese military personnel arelower, compared to the Chinese general Population, which show significantly different ingender, troops, rank, degree of educational background, economic and cultural region, thelength of military service and age.2. Environmental factors(such as life events) and genetic factors, shall be the primaryfactors of depression, followed by which are smoking, drinking and insufficient exercises.Chronic drug use and chronic diseases are also regarded as the risk factors. Specialoperating environment (eg. missile operation, artillery operation, tank operation, radaroperation, electronic warfare and communication operations, chemical defense operations),special natrual environment (eg. tropical environment, cold environment, high altitudehypoxia environment, tunnel environment) and training injuries are all the risk factors ofthe occurrence of depressive symptoms in Chinese military personnel.3. Military life events, such as great employment pressure in future, heavy work,distrust of others, lovelorn, falling ill or being injured increase the risk of depression.However, social support could moderate and relieve the depression.