- Email: [email protected]
An investigation of the prevalence of depressive symptoms in soldiers during military training
Preventive Medicine 41 (2005) 642 – 645 www.elsevier.com/locate/ypmed
An investigation of the prevalence of depressive symptoms in soldiers during military training Hongyan Xiong, M.D., Ph.D.T, Xiaoming Zhang, Yao Zhang, Fei Ma, Yafei Li, Li Li Department of Epidemiology, 3rd Military Medical University, Chongqing 400038, PR China Available online 11 April 2005
Abstract Objectives. A cross-sectional study was conducted to determine the prevalence of depressive symptoms in soldiers during military training in Chinese army and to identify associations between depressive symptoms and socio-demographic characteristics. Methods. The self-rating depression scale (SDS) was used to assess self-reported experiences of depression among 1107 young adult males during military training. The following socio-demographic variables are considered as independent variables: age, service time, settlement type, education, levels of family income, family type, education of parents, health status, history of negative accidents, social support status and hobby status. A logistic regression model was used to estimate the association of these variables with depressive symptoms. Results. 25.20% (n = 279) of the servicemen had depressive symptoms. The soldiers who had high education level (OR = 1.74; 95%CI: 1.37–2.12), come from city or town (OR = 1.39; 95%CI: 1.18–1.61), have served in army for a shorter time (OR = 1.63; 95%CI: 1.43–1.88), had head ache during training course (OR = 1.39; 95%CI: 1.12–2.09), had abdomen ache or diarrhea during training course (OR = 1.85; 95%CI: 1.47–2.13) and had training injury during training course (OR = 1.67; 95%CI: 1.29–1.83) are associated with depressive symptoms. Conclusions. There was a high prevalence rate of depressive symptoms among soldiers during military training. Special attention should be paid to avoiding depressive symptoms in those who have high education level, come from city or town, have served in army for a shorter time and have health problems during training course. D 2005 Elsevier Inc. All rights reserved. Keywords: Soldiers; Depressive symptoms; Logistic regression; Cross-sectional study
Introduction The military service constitutes a unique community with its hierarchic and disciplinary structure, tiresome training applications and separate nature. It is also an environment in which personal, cultural and social differences are not taken into account, and intensive physical effort is required. Soldiers are moved away from the social and physical environment to which they are accustomed and start to live in an unfamiliar new environment with rigidly defined rules. This new environment, with its hierarchical structure and discipline-based order, calls for adaptation to a life style much different from the civilian environment. Various
T Corresponding author. E-mail address: [email protected] (H. Xiong). 0091-7435/$ - see front matter D 2005 Elsevier Inc. All rights reserved. doi:10.1016/j.ypmed.2005.01.010
studies conducted on the military personnel in other countries have indicated that depression is an important health problem in this population. In a study conducted on 470 army enlisted men who returned from Vietnam and were interviewed, 26% of the participants were found to have depressive symptoms [1]. Another study investigated about 1138 Air Force recruits in the US who were referred for mental health evaluation while in basic military training, it was found that the most frequent diagnosis was depressive disorders, which accounted for 31% of all diagnoses [2]. Similar studies also reported that 29.9% of the recruits had depressive symptoms in the Turkish army, and the recruits who smoked or drank, who had low incomes and who were uninterested in sports had higher Beck Depression Inventory (BDI) scores [3]. In recent years, the mental health has been paid more attention to by medical research and public health office of
H. Xiong et al. / Preventive Medicine 41 (2005) 642–645
China. The results of several epidemiologic investigations carried out in different population show that the prevalence of depressive symptoms found in non-military population is about 16–20% [4–7]. But until now, little study in China has been conducted on the prevalence of depressive symptoms among the young adult population during military training.
Methods Subjects and subject selection To determine the prevalence and nature of depressive symptoms among young adult males during their 8 week field military training in southern area of China, a survey was held at the end of August, 2002, the last week of training. We chose south area of China because this military training center has the general fighting training courses with modern military techniques. There, the type of training provides more of a real-world combat training scenario and makes one feel more stressful. The survey was a systematic random sample of all soldiers in the training center. A random sample of 1220 male soldiers from training group who agreed to undergo a psychological assessment was targeted. They were administered the SDS and an additional questionnaire containing 25 questions on socio-demographic characteristics. After the administration, 113 persons were found to have filled out the forms inadequately (such as marking multiple responses where only one response was required, or not responding to four or more questions in the SDS) and these were excluded from the analysis. Finally, a total of 1107 subjects were included in the analysis. Instrument The Chinese version of the SDS was used to determine the prevalence of depressive symptoms. The Chinese form of the SDS has been translated from Zung Self-rating Depression scale in 1985.It has been shown to have adequate reliability and validity [8,9]. Symptoms of depression were assessed using the 20-item Zung self-rating depression scale [10,11]. Items were rated 1–4 with higher scores representing greater symptom severity. The SDS Index has been widely used to evaluate depressive symptoms in medically ill patients and general population [7,12–14].
643
would remain confidential and not be released. They were asked to answer the questions on their own, not to write their names on the forms. During the administration, none of the commanders of the soldiers were present at the field. The investigators were the experts of our department who were assigned to administer the forms to the soldiers. Before administering the forms, the investigators were trained on how to fill out the forms. During the study, they simply distributed the forms to literate respondents and collected the completed forms. Demographic data were obtained from the participants with an additional questionnaire form. Data were analyzed by the experts using software of SPSS, version 11.0. Logistic regression model was used to identify significant socio-demographic covariates. The age, service time, settlement type, education, level of family income, family type, education of parents, health status, history of negative accidents, social support status and hobby status were selected for multivariate analysis. Definitions used in the study The prevalence of depressive symptoms was investigated. SDS item points of every participant were added and those reaching 51 points or more were accepted to be dwith depressive symptomsT. Every question of the SDS had four choices and d1 ptT was assigned for daT, d2 ptT for dbT, d3 ptT for dcT and d4 ptT for ddT [10,11]. Settlement types (which refer to the type of settlement) were grouped according to where the participants lived before conscription. The history of negative accidents was grouped according to whether the participants once suffered strong psychological stress from accident in life. Social support and interpersonal relations status were grouped according to whether the participants had a good social support or interpersonal environment. Having one or several buddy and a good relationship with family members, leaders and comrades reflect the good social support or interpersonal environment. Health status was grouped according to whether the participants had some uncomfortable symptoms, such as headache, abdomen ache, diarrhea and training injury. Hobby status was grouped according to whether the participants had one or more hobby in life.
Results Procedure At the first and second day of the last week of combat training, the questionnaire forms were administered to all of the respondents at the same time. It was done when the soldiers were gathered in the field for the afternoon training after lunch. A guarantee and necessary explanations on top of the questionnaire form assured them that the information
Mean age of evaluated participants (n = 1107) was 19.93 F 1.06 (range 17–24) and 79.0% of them (875 persons) were age 20–21. Depressive symptoms were detected by the SDS in 25.20% (279 persons) of the study group. Table 1 shows univariate and multivariate logistic models for the variable presence of depressive symptoms.
644
H. Xiong et al. / Preventive Medicine 41 (2005) 642–645
Table 1 Influence of the characteristics of soldiers on SDS scores S-demographic characteristics
Low depressive symptoms group (0–50)
Univariate odds ratio (95%CI)
Multivariate odds ratio (95%CI)
n
(%)
n
(%)
Total Age Q20 (17–20) N20 (21–24) Service times 1 year 2 year Settlement type Village City or town Education status QMiddle school RHigh school Levels of family income (RMB/year) Q3000 N3000 Family type Nuclear family Patriarchal family Mother QMiddle school NMiddle school Father QMiddle school NMiddle school Health status Head ache Yes No Abdomen ache or diarrhea Yes No Training injury Yes No History of negative accidents Yes No Social support Good Bad Hobby status Yes No
828 324 504
74.80 74.31 75.11
279 112 167
25.20 25.69 24.88
0.95 (0.72; 1.27) 0.85 (062; 1.04)
0.87 (0.69; 1.10) 0.70 (0.55; 1.13)
356 472
71.92 77.12
139 140
28.10 22.88
1.56 (1.14; 2.03) 0.76 (0.39; 1.09)
1.63 (1.43; 1.88) 0.87 (0.69; 1.23)
598 230
76.57 70.55
183 96
23.43 29.45
9.30 (0.68; 1.07) 1.36 (1.02; 1.82)
0.90 (0.80; 1.08) 1.39 (1.18; 1.61)
425 403
78.85 70.75
114 165
21.15 29.05
0.66 (0.58; 1.12) 1.53 (1.16; 2.01)
0.74 (0.60; 1.04) 1.74 (1.37; 2.12)
702 126
75.08 73.26
233 46
24.92 26.67
0.83 (0.62; 1.34) 1.10 (0.76; 1.59)
0.92 (0.70; 1.35) 1.00 (0.81; 1.20)
716 112
74.82 74.67
241 38
25.18 25.33
1.01 (0.95; 1.13) 1.07 (0.91; 1.11)
1.12 (0.72; 1.03) 1.07 (0.81; 1.19)
252 576
74.33 75.00
87 192
25.66 25.00
0.97 (0.72; 1.30) 1.14 (0.76; 1.41)
0.98 (0.79; 1.20) 1.12 (0.56; 2.24)
544 284
74.52 75.53
187 92
25.58 24.47
0.94 (0.71; 1.26) 0.86 (0.61; 1.01
0.95 (0.69; 1.18) 0.95 (0.76; 1.32)
103 725
69.60 75.60
45 234
30.40 24.40
1.35 (1.09; 2.03) 0.74 (0.52; 1.02)
1.39 (1.12; 2.09) 0.85 (0.69; 1.23)
82 746
66.13 75.89
42 237
33.87 24.11
1.61 (1.08; 2.40) 0.82 (0.56; 1.21)
1.85 (1.47; 2.13) 0.70 (0.60; 1.03)
113 715
67.26 76.14
55 224
32.74 23.86
1.55 (1.10; 2.22) 0.92 (0.79; 1.37)
1.67 (1.29; 1.83) 1.01 (0.77; 1.15)
43 785
74.14 74.83
15 264
25.86 25.17
1.04 (0.57; 1.90) 0.97 (0.54; 1.71)
1.19 (0.96; 1.22) 0.89 (0.55; 1.23)
733 95
74.95 73.64
245 34
25.05 26.36
0.86 (0.60; 1.10) 0.93 (0.62; 1.02)
0.72 (0.66; 1.56) 1.10 (0.95; 1.80)
453 375
74.26 75.45
157 122
25.74 24.55
1.07 (0.81; 1.40) 0.95 (0.79; 1.17)
0.96 (0.74; 1.17) 0.96 (0.58; 2.01)
Both in univariate analysis and multivariate analysis, the data show that the soldiers who had high education level (OR = 1.74; 95%CI: 1.37–2.12), came from city or town (OR = 1.39; 95%CI: 1.18–1.61), served in army for a shorter time (OR = 1.63; 95%CI: 1.43–1.88), had head ache during training course (OR = 1.39; 95%CI: 1.12– 2.09), had abdomen ache or diarrhea during training course (OR = 1.85; 95%CI: 1.47–2.13) and had training injury during training course (OR = 1.67; 95%CI: 1.29– 1.83) are associated with depressive symptoms. However, age, level of family income, family type, education of
High depressive symptoms group (51–80)
parents, history of negative accidents, social support status and hobby status variables are not associated with the outcome.
Discussion Military operation imposes severe limitation on personal freedom and job decision latitude. Training in harsh conditions and frequent unplanned separation from family and friends are common. The work conditions that involve
H. Xiong et al. / Preventive Medicine 41 (2005) 642–645
environment stress and low control may exacerbate strain and play an important role in the onset of specific mental health problems [15–17]. The prevalence rate of 25.20% pertaining to the presence of soldiers dwith depressive symptomsT found in this study is higher than scores of nonmilitary population obtained in our country earlier [4–7]. In our study, the SDS was administered to the soldiers in the last week of their military fighting training. Their responses to the SDS might well have been influenced by the proximate stressful life event of military task, i.e. by environment stress and heavy physical workload stress that was likely to differently affect those unfamiliar with the training environment. According to the study, the participants that came from city or town had a higher prevalence of depressive symptoms than those from villages. It can be assumed that the soldiers from city or town were likely to have more comfortable and socialized life style before conscription than the rural area group. It may have rendered them more fragile in adapting to the life style imposed by military training. Various studies indicated the association of negative accident in life and social support status with depression. Having the negative accident in life and lacking the social support were found to be the risk factors for depression [18– 20]. But in our study, there is no difference between the groups of soldiers with different status of social support and negative accident in life. It might be the result of special environment during fighting training course. There, the participants had special heavy physical workload and mental stress. The risk factors were somewhat different from that in normal active duty time. Differences observed in this study of the prevalence of depressive symptoms among those with different service time, different settlement type and different level of education raise the idea of instituting some precautions during military training, including health education targeted on recruit, soldiers from city or town, soldiers that have high level education (high school graduates and junior high school) and preparation of the suitable training course for decrease the training injury. The conclusions derived from this study have to be corroborated in further works. Taking the high prevalence rate of depressive symptoms among soldiers during fighting training field into consideration, they should be assessed carefully and referred for appropriate mental health care.
645
References [1] Helzer JE, Robins LN, Davis DH. Depressive disorders in Vietnam returnees. J Nerv Ment Dis 1976;163:177 – 85. [2] Cigrang JA, Carbone EG, Todd S, et al. Mental health attrition from Air Force basic military training. Mil Med 1998;163:834 – 8. ¨ .F., Ceylan S, Hamzaog˘lu O, et al. An investigation of the [3] Tekbas O prevalence of depressive symptoms in newly recruited young adult men in Turkey. Psychiatry Res 2003;119:155 – 62. [4] Stewart SM, Betson CL, Lam TH, et al. The correlates of depressed mood in adolescents in Hong Kong. J Adolesc Health 1999;25:27 – 34. [5] Guihua Z, Jingxuan Z, Zheng W. Depressive symptom and risk factors in people living in rural area of Shandong province. Chin Ment Health J 2001;15:342 – 5 [in Chinese]. [6] Fuyuan L, Tianhong X, Yan Z, et al. Mental state of researchers in the Antarctic region. Chin Ment Health J 2000;14:364 – 6 [in Chinese]. [7] Lee HC, Chiu HF, Wing YK, et al. The Zung Self-rating Depression Scale: screening for depression among the Hong Kong Chinese elderly. J Geriatr Psychiatry Neurol 1994;7:216 – 20. [8] Xiancheng Liu, Wuqin Tang, Kun Cheng, et al. The evaluation about depressive symptom of collage students determined by SDS and CESD. Chin Ment Health J 1995;9:19 – 21 [in Chinese]. [9] Zung WW. Zung Self-rating depression scale, and depression status inventory. In: Satorious N, Ban T, editors. Assessment of Depression. New York7 Springer-Verlag; 1986. p. 221 – 31. [10] Zung WW. A self-rating depression scale. Arch Gen Psychiatry 1965;12:63 – 70. [11] Zung WW. From art to science. Arch Gen Psychiatry 1973;29: 328 – 37. [12] Koenig HG, Cohen HJ, Blazer DG, et al. A brief depression scale for use in the medically ill. Int J Psychiatry Med 1992;22:183 – 95. [13] Malaguarnera M, Di Fazio I, Restuccia S, et al. Interferon alphainduced depression in chronic hepatitis C patients: comparison between different types of interferon alpha. Neuropsychobiology 1998;37:93 – 7. [14] Chunbo L, Yanling H, Mingyuan Z. The impact of depressive symptoms on psychological and physical outcomes: a 5-year follow up study of elderly at the community level. Chin J Epidemiol 2002;23:341 – 4 [in Chinese]. [15] Garvey-Wilson AL, Lange JL, Brundage JF, et al. Behavioral, demographic, and prior morbidity risk factors for accidental death among men: a case-control study of soldiers. Prev Med 2003;36: 124 – 30. [16] Ren XS, Skinner K, Lee A, et al. Social support, social selection and self-assessed health status: results from the veterans health study in the United States. Soc Sci Med 1999;48:1721 – 34. [17] Sutker PB, Allain AN. Psychological assessment of aviators captured in World War II. Psychol Assess 1995;7:66 – 8. [18] Blanchard EB, Hickling EJ, Taylor AE, et al. Psychological morbidity associated with motor vehicle accidents. Behav Res Ther 1994;32: 283 – 90. [19] Weeke A, V&th M. Excess mortality of bipolar and unipolar manicdepressive patients. J Affect Dis. 11:227 – 34. [20] McDonald AS, Davey G.C. Psychiatric disorders and accidental injury. Clin Psychol Rev 1996;16:105 – 27.
An investigation of the prevalence of depressive symptoms in soldiers during military training Hongyan Xiong, M.D., Ph.D.T, Xiaoming Zhang, Yao Zhang, Fei Ma, Yafei Li, Li Li Department of Epidemiology, 3rd Military Medical University, Chongqing 400038, PR China Available online 11 April 2005
Abstract Objectives. A cross-sectional study was conducted to determine the prevalence of depressive symptoms in soldiers during military training in Chinese army and to identify associations between depressive symptoms and socio-demographic characteristics. Methods. The self-rating depression scale (SDS) was used to assess self-reported experiences of depression among 1107 young adult males during military training. The following socio-demographic variables are considered as independent variables: age, service time, settlement type, education, levels of family income, family type, education of parents, health status, history of negative accidents, social support status and hobby status. A logistic regression model was used to estimate the association of these variables with depressive symptoms. Results. 25.20% (n = 279) of the servicemen had depressive symptoms. The soldiers who had high education level (OR = 1.74; 95%CI: 1.37–2.12), come from city or town (OR = 1.39; 95%CI: 1.18–1.61), have served in army for a shorter time (OR = 1.63; 95%CI: 1.43–1.88), had head ache during training course (OR = 1.39; 95%CI: 1.12–2.09), had abdomen ache or diarrhea during training course (OR = 1.85; 95%CI: 1.47–2.13) and had training injury during training course (OR = 1.67; 95%CI: 1.29–1.83) are associated with depressive symptoms. Conclusions. There was a high prevalence rate of depressive symptoms among soldiers during military training. Special attention should be paid to avoiding depressive symptoms in those who have high education level, come from city or town, have served in army for a shorter time and have health problems during training course. D 2005 Elsevier Inc. All rights reserved. Keywords: Soldiers; Depressive symptoms; Logistic regression; Cross-sectional study
Introduction The military service constitutes a unique community with its hierarchic and disciplinary structure, tiresome training applications and separate nature. It is also an environment in which personal, cultural and social differences are not taken into account, and intensive physical effort is required. Soldiers are moved away from the social and physical environment to which they are accustomed and start to live in an unfamiliar new environment with rigidly defined rules. This new environment, with its hierarchical structure and discipline-based order, calls for adaptation to a life style much different from the civilian environment. Various
T Corresponding author. E-mail address: [email protected] (H. Xiong). 0091-7435/$ - see front matter D 2005 Elsevier Inc. All rights reserved. doi:10.1016/j.ypmed.2005.01.010
studies conducted on the military personnel in other countries have indicated that depression is an important health problem in this population. In a study conducted on 470 army enlisted men who returned from Vietnam and were interviewed, 26% of the participants were found to have depressive symptoms [1]. Another study investigated about 1138 Air Force recruits in the US who were referred for mental health evaluation while in basic military training, it was found that the most frequent diagnosis was depressive disorders, which accounted for 31% of all diagnoses [2]. Similar studies also reported that 29.9% of the recruits had depressive symptoms in the Turkish army, and the recruits who smoked or drank, who had low incomes and who were uninterested in sports had higher Beck Depression Inventory (BDI) scores [3]. In recent years, the mental health has been paid more attention to by medical research and public health office of
H. Xiong et al. / Preventive Medicine 41 (2005) 642–645
China. The results of several epidemiologic investigations carried out in different population show that the prevalence of depressive symptoms found in non-military population is about 16–20% [4–7]. But until now, little study in China has been conducted on the prevalence of depressive symptoms among the young adult population during military training.
Methods Subjects and subject selection To determine the prevalence and nature of depressive symptoms among young adult males during their 8 week field military training in southern area of China, a survey was held at the end of August, 2002, the last week of training. We chose south area of China because this military training center has the general fighting training courses with modern military techniques. There, the type of training provides more of a real-world combat training scenario and makes one feel more stressful. The survey was a systematic random sample of all soldiers in the training center. A random sample of 1220 male soldiers from training group who agreed to undergo a psychological assessment was targeted. They were administered the SDS and an additional questionnaire containing 25 questions on socio-demographic characteristics. After the administration, 113 persons were found to have filled out the forms inadequately (such as marking multiple responses where only one response was required, or not responding to four or more questions in the SDS) and these were excluded from the analysis. Finally, a total of 1107 subjects were included in the analysis. Instrument The Chinese version of the SDS was used to determine the prevalence of depressive symptoms. The Chinese form of the SDS has been translated from Zung Self-rating Depression scale in 1985.It has been shown to have adequate reliability and validity [8,9]. Symptoms of depression were assessed using the 20-item Zung self-rating depression scale [10,11]. Items were rated 1–4 with higher scores representing greater symptom severity. The SDS Index has been widely used to evaluate depressive symptoms in medically ill patients and general population [7,12–14].
643
would remain confidential and not be released. They were asked to answer the questions on their own, not to write their names on the forms. During the administration, none of the commanders of the soldiers were present at the field. The investigators were the experts of our department who were assigned to administer the forms to the soldiers. Before administering the forms, the investigators were trained on how to fill out the forms. During the study, they simply distributed the forms to literate respondents and collected the completed forms. Demographic data were obtained from the participants with an additional questionnaire form. Data were analyzed by the experts using software of SPSS, version 11.0. Logistic regression model was used to identify significant socio-demographic covariates. The age, service time, settlement type, education, level of family income, family type, education of parents, health status, history of negative accidents, social support status and hobby status were selected for multivariate analysis. Definitions used in the study The prevalence of depressive symptoms was investigated. SDS item points of every participant were added and those reaching 51 points or more were accepted to be dwith depressive symptomsT. Every question of the SDS had four choices and d1 ptT was assigned for daT, d2 ptT for dbT, d3 ptT for dcT and d4 ptT for ddT [10,11]. Settlement types (which refer to the type of settlement) were grouped according to where the participants lived before conscription. The history of negative accidents was grouped according to whether the participants once suffered strong psychological stress from accident in life. Social support and interpersonal relations status were grouped according to whether the participants had a good social support or interpersonal environment. Having one or several buddy and a good relationship with family members, leaders and comrades reflect the good social support or interpersonal environment. Health status was grouped according to whether the participants had some uncomfortable symptoms, such as headache, abdomen ache, diarrhea and training injury. Hobby status was grouped according to whether the participants had one or more hobby in life.
Results Procedure At the first and second day of the last week of combat training, the questionnaire forms were administered to all of the respondents at the same time. It was done when the soldiers were gathered in the field for the afternoon training after lunch. A guarantee and necessary explanations on top of the questionnaire form assured them that the information
Mean age of evaluated participants (n = 1107) was 19.93 F 1.06 (range 17–24) and 79.0% of them (875 persons) were age 20–21. Depressive symptoms were detected by the SDS in 25.20% (279 persons) of the study group. Table 1 shows univariate and multivariate logistic models for the variable presence of depressive symptoms.
644
H. Xiong et al. / Preventive Medicine 41 (2005) 642–645
Table 1 Influence of the characteristics of soldiers on SDS scores S-demographic characteristics
Low depressive symptoms group (0–50)
Univariate odds ratio (95%CI)
Multivariate odds ratio (95%CI)
n
(%)
n
(%)
Total Age Q20 (17–20) N20 (21–24) Service times 1 year 2 year Settlement type Village City or town Education status QMiddle school RHigh school Levels of family income (RMB/year) Q3000 N3000 Family type Nuclear family Patriarchal family Mother QMiddle school NMiddle school Father QMiddle school NMiddle school Health status Head ache Yes No Abdomen ache or diarrhea Yes No Training injury Yes No History of negative accidents Yes No Social support Good Bad Hobby status Yes No
828 324 504
74.80 74.31 75.11
279 112 167
25.20 25.69 24.88
0.95 (0.72; 1.27) 0.85 (062; 1.04)
0.87 (0.69; 1.10) 0.70 (0.55; 1.13)
356 472
71.92 77.12
139 140
28.10 22.88
1.56 (1.14; 2.03) 0.76 (0.39; 1.09)
1.63 (1.43; 1.88) 0.87 (0.69; 1.23)
598 230
76.57 70.55
183 96
23.43 29.45
9.30 (0.68; 1.07) 1.36 (1.02; 1.82)
0.90 (0.80; 1.08) 1.39 (1.18; 1.61)
425 403
78.85 70.75
114 165
21.15 29.05
0.66 (0.58; 1.12) 1.53 (1.16; 2.01)
0.74 (0.60; 1.04) 1.74 (1.37; 2.12)
702 126
75.08 73.26
233 46
24.92 26.67
0.83 (0.62; 1.34) 1.10 (0.76; 1.59)
0.92 (0.70; 1.35) 1.00 (0.81; 1.20)
716 112
74.82 74.67
241 38
25.18 25.33
1.01 (0.95; 1.13) 1.07 (0.91; 1.11)
1.12 (0.72; 1.03) 1.07 (0.81; 1.19)
252 576
74.33 75.00
87 192
25.66 25.00
0.97 (0.72; 1.30) 1.14 (0.76; 1.41)
0.98 (0.79; 1.20) 1.12 (0.56; 2.24)
544 284
74.52 75.53
187 92
25.58 24.47
0.94 (0.71; 1.26) 0.86 (0.61; 1.01
0.95 (0.69; 1.18) 0.95 (0.76; 1.32)
103 725
69.60 75.60
45 234
30.40 24.40
1.35 (1.09; 2.03) 0.74 (0.52; 1.02)
1.39 (1.12; 2.09) 0.85 (0.69; 1.23)
82 746
66.13 75.89
42 237
33.87 24.11
1.61 (1.08; 2.40) 0.82 (0.56; 1.21)
1.85 (1.47; 2.13) 0.70 (0.60; 1.03)
113 715
67.26 76.14
55 224
32.74 23.86
1.55 (1.10; 2.22) 0.92 (0.79; 1.37)
1.67 (1.29; 1.83) 1.01 (0.77; 1.15)
43 785
74.14 74.83
15 264
25.86 25.17
1.04 (0.57; 1.90) 0.97 (0.54; 1.71)
1.19 (0.96; 1.22) 0.89 (0.55; 1.23)
733 95
74.95 73.64
245 34
25.05 26.36
0.86 (0.60; 1.10) 0.93 (0.62; 1.02)
0.72 (0.66; 1.56) 1.10 (0.95; 1.80)
453 375
74.26 75.45
157 122
25.74 24.55
1.07 (0.81; 1.40) 0.95 (0.79; 1.17)
0.96 (0.74; 1.17) 0.96 (0.58; 2.01)
Both in univariate analysis and multivariate analysis, the data show that the soldiers who had high education level (OR = 1.74; 95%CI: 1.37–2.12), came from city or town (OR = 1.39; 95%CI: 1.18–1.61), served in army for a shorter time (OR = 1.63; 95%CI: 1.43–1.88), had head ache during training course (OR = 1.39; 95%CI: 1.12– 2.09), had abdomen ache or diarrhea during training course (OR = 1.85; 95%CI: 1.47–2.13) and had training injury during training course (OR = 1.67; 95%CI: 1.29– 1.83) are associated with depressive symptoms. However, age, level of family income, family type, education of
High depressive symptoms group (51–80)
parents, history of negative accidents, social support status and hobby status variables are not associated with the outcome.
Discussion Military operation imposes severe limitation on personal freedom and job decision latitude. Training in harsh conditions and frequent unplanned separation from family and friends are common. The work conditions that involve
H. Xiong et al. / Preventive Medicine 41 (2005) 642–645
environment stress and low control may exacerbate strain and play an important role in the onset of specific mental health problems [15–17]. The prevalence rate of 25.20% pertaining to the presence of soldiers dwith depressive symptomsT found in this study is higher than scores of nonmilitary population obtained in our country earlier [4–7]. In our study, the SDS was administered to the soldiers in the last week of their military fighting training. Their responses to the SDS might well have been influenced by the proximate stressful life event of military task, i.e. by environment stress and heavy physical workload stress that was likely to differently affect those unfamiliar with the training environment. According to the study, the participants that came from city or town had a higher prevalence of depressive symptoms than those from villages. It can be assumed that the soldiers from city or town were likely to have more comfortable and socialized life style before conscription than the rural area group. It may have rendered them more fragile in adapting to the life style imposed by military training. Various studies indicated the association of negative accident in life and social support status with depression. Having the negative accident in life and lacking the social support were found to be the risk factors for depression [18– 20]. But in our study, there is no difference between the groups of soldiers with different status of social support and negative accident in life. It might be the result of special environment during fighting training course. There, the participants had special heavy physical workload and mental stress. The risk factors were somewhat different from that in normal active duty time. Differences observed in this study of the prevalence of depressive symptoms among those with different service time, different settlement type and different level of education raise the idea of instituting some precautions during military training, including health education targeted on recruit, soldiers from city or town, soldiers that have high level education (high school graduates and junior high school) and preparation of the suitable training course for decrease the training injury. The conclusions derived from this study have to be corroborated in further works. Taking the high prevalence rate of depressive symptoms among soldiers during fighting training field into consideration, they should be assessed carefully and referred for appropriate mental health care.
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References [1] Helzer JE, Robins LN, Davis DH. Depressive disorders in Vietnam returnees. J Nerv Ment Dis 1976;163:177 – 85. [2] Cigrang JA, Carbone EG, Todd S, et al. Mental health attrition from Air Force basic military training. Mil Med 1998;163:834 – 8. ¨ .F., Ceylan S, Hamzaog˘lu O, et al. An investigation of the [3] Tekbas O prevalence of depressive symptoms in newly recruited young adult men in Turkey. Psychiatry Res 2003;119:155 – 62. [4] Stewart SM, Betson CL, Lam TH, et al. The correlates of depressed mood in adolescents in Hong Kong. J Adolesc Health 1999;25:27 – 34. [5] Guihua Z, Jingxuan Z, Zheng W. Depressive symptom and risk factors in people living in rural area of Shandong province. Chin Ment Health J 2001;15:342 – 5 [in Chinese]. [6] Fuyuan L, Tianhong X, Yan Z, et al. Mental state of researchers in the Antarctic region. Chin Ment Health J 2000;14:364 – 6 [in Chinese]. [7] Lee HC, Chiu HF, Wing YK, et al. The Zung Self-rating Depression Scale: screening for depression among the Hong Kong Chinese elderly. J Geriatr Psychiatry Neurol 1994;7:216 – 20. [8] Xiancheng Liu, Wuqin Tang, Kun Cheng, et al. The evaluation about depressive symptom of collage students determined by SDS and CESD. Chin Ment Health J 1995;9:19 – 21 [in Chinese]. [9] Zung WW. Zung Self-rating depression scale, and depression status inventory. In: Satorious N, Ban T, editors. Assessment of Depression. New York7 Springer-Verlag; 1986. p. 221 – 31. [10] Zung WW. A self-rating depression scale. Arch Gen Psychiatry 1965;12:63 – 70. [11] Zung WW. From art to science. Arch Gen Psychiatry 1973;29: 328 – 37. [12] Koenig HG, Cohen HJ, Blazer DG, et al. A brief depression scale for use in the medically ill. Int J Psychiatry Med 1992;22:183 – 95. [13] Malaguarnera M, Di Fazio I, Restuccia S, et al. Interferon alphainduced depression in chronic hepatitis C patients: comparison between different types of interferon alpha. Neuropsychobiology 1998;37:93 – 7. [14] Chunbo L, Yanling H, Mingyuan Z. The impact of depressive symptoms on psychological and physical outcomes: a 5-year follow up study of elderly at the community level. Chin J Epidemiol 2002;23:341 – 4 [in Chinese]. [15] Garvey-Wilson AL, Lange JL, Brundage JF, et al. Behavioral, demographic, and prior morbidity risk factors for accidental death among men: a case-control study of soldiers. Prev Med 2003;36: 124 – 30. [16] Ren XS, Skinner K, Lee A, et al. Social support, social selection and self-assessed health status: results from the veterans health study in the United States. Soc Sci Med 1999;48:1721 – 34. [17] Sutker PB, Allain AN. Psychological assessment of aviators captured in World War II. Psychol Assess 1995;7:66 – 8. [18] Blanchard EB, Hickling EJ, Taylor AE, et al. Psychological morbidity associated with motor vehicle accidents. Behav Res Ther 1994;32: 283 – 90. [19] Weeke A, V&th M. Excess mortality of bipolar and unipolar manicdepressive patients. J Affect Dis. 11:227 – 34. [20] McDonald AS, Davey G.C. Psychiatric disorders and accidental injury. Clin Psychol Rev 1996;16:105 – 27.