Objective: The aims of this paper are to determine the risk factors for combat-related posttraumatic stress disorder (PTSD) and to examine the relative contribution of pre-military factors, pre-trauma psychiatric diagnoses, military factors such as combat posting, and combat and casualty stress exposure.
Method: An epidemiological cohort study using standardised psychiatric, social and health interviews was undertaken with a national random sample of male Australian Army Vietnam veterans. Multivariate logistic regression was used to examine the relative contribution of factors derived from interview and from military records in four categories: pre-enlistment circumstances including home life, education, major life stress; pre-Vietnam psychiatric diagnoses; military experiences before and during Vietnam; and combat and stress experiences.
Results: Of the 128 data items examined, significant associations were found for 39, in addition to combat stress. Pre-enlistment items accounted for about 3% of the deviance towards PTSD diagnosis, pre-enlistment psychiatric diagnosis about 13%, military variables about 7% and combat stress about 18%; all factors together accounted for 42%.
Conclusions: The results confirm that pre-military and military variables make only a small but significant contribution to PTSD either alone or after controlling for combat stress; that psychiatric diagnoses of depression, dysthymia and agoraphobia make strong contributions to PTSD; but that combat stress makes the largest contribution even after controlling for the effects of other variables. Psychiatric diagnoses and combat stress appear to be independent in their effects on PTSD.
CardJ.Lives After Vietnam: the personal impact of military service. Lexington MA: Lexington Books, 1983.
2.
EgendorfAKadushinCLauferRSRothbartGSloanL.Legacies of Vietnam: comparative adjustment of veterans and their peers. Washington, DC: Center for Policy Research, 1981.
3.
LauferRSGallopsMSFrey-WoutersE.War stress and trauma: the Vietnam veteran experience. Journal of Health and Social Behaviour1984; 25:65–85.
4.
WilsonJPKraussGEPredicting post-traumatic stress disorder among Vietnam veterans. In: KellyE, ed. Posttraumatic stress disorder and the war veteran patient. New York: Brunner/Mazel, 1985.
5.
SolomonZMikulincerM.Combat stress reactions, post traumatic stress disorder and somatic complaints among Israeli soldiers. Journal of Psychosomatic Research1987; 31:131–137.
6.
SnowBRStellmanJMNStellmanSDSommerJFPosttraumatic stress disorder among American Legionnaires in relation to combat experience in Vietnam: associated and contributing factors. Environmental Research1988; 47:175–192.
7.
GradyDAWoolfolkFLBudneyAJDimensions of war zone stress: an empirical analysis. Journal of Nervous and Mental Disease1989; 177:347–350.
8.
KeaneTMFairbankJACaddellJMZimmeringRTTaylorKLMoraCAClinical evaluation of a measure to assess combat exposure. Psychological Assessment1989; 1:53–55.
9.
DecouflePHolmgreenPBoyleCStroupNESelf-reported health status of Vietnam veterans in relation to perceived exposure to herbicides and combat. American Journal of Epidemiology1987; 135:312–323.
10.
Centers for Disease Control.Vietnam experience study: health status of Vietnam veterans. I. Psychosocial characteristics. Journal of the American Medical Association1988; 259:2701–2707.
11.
Centers for Disease Control.Vietnam experience study: health status of Vietnam veterans. II. Physical health. Journal of the American Medical Association1988; 259:2708–2714.
12.
KulkaRASchlengerWEFairbankJAHoughRLJordanBKMarmarCRWeissDSTrauma and the Vietnam generation. Report of findings from the national Vietnam veterans readjustment study. Vol 1. New York: Brunner/Mazel, 1990.
13.
KulkaRASchlengerWEFairbankJAHoughRLJordanBKMarmarCRWeissDSThe national Vietnam veterans readjustment study. Vol II. Tables of Findings and Technical Appendices. New York: Brunner/Mazel, 1990.
14.
FontanaARosenheckRBrettE.War zone traumas and posttraumatic stress disorder symptomatology. Journal of Nervous and Mental Disease1992; 180:748–755.
15.
NaceEPO'BrienCPMintzJReamNMeyersALAdjustment among Vietnam veteran drug users two years post-service. In: FigleyCR, ed. Stress disorders among Vietnam veterans: theory, research and treatment. New York: Brunner/Mazel, 1978.
16.
LauferRSYaegerTFrey-WoutersEDonnellanJ.Legacies of Vietnam. III. Post-war trauma. Washington, DC: US Government Printing Office, 1981.
17.
GoldbergJTrueWREisenSAHendersonWGA twin study of the effects of the Vietnam war on posttraumatic stress disorder. Journal of the American Medical Association1990; 263:1227–1232.
18.
FoyDWCarrollEMDonahoeCPEtiological factors in the development of PTSD in clinical samples of Vietnam combat veterans. Journal of Clinical Psychology1987; 43:17–27.
19.
BreslauNDavisGCPosttraumatic stress disorder: the etiologic specificity of wartime stressors. American Journal of Psychiatry1987; 144:578–583.
20.
McFarlaneACThe aetiology of post-traumatic morbidity: predisposing, precipitating and perpetuating factors. British Journal of Psychiatry1989; 154:221–228.
21.
BreslauNDavisGCAndreskiPPetersenE.Traumatic events and posttraumatic stress disorder in an urban population of young adults. Archives of General Psychiatry1991; 48:216–222.
22.
ResnickHSKilpatrickDGBestCLKramerTLVulnerability-stress factors in development of posttraumatic stress disorder. Journal of Nervous and Mental Disease1992; 180:424–430.
23.
American Psychiatric Association.Diagnostic and statistical manual of mental disorders. 3rd ed.Washington, DC: American Psychiatric Association Press, 1980.
24.
JonesJCBarlowDHThe etiology of posttraumatic stress disorder. Clinical Psychology Review1990; 10:299–328.
25.
GreenBLWilsonJPLindyJ.A conceptual framework for post-traumatic stress syndromes among survivor groups. In: FigleyCR, ed. Trauma and its wake: the study and treatment of post-traumatic stress disorder. New York: Brunner/Mazel, 1985.
26.
SolomonZMikulincerMFlumH.The implications of life events and social integration in the course of combat-related post-traumatic stress disorder. Social Psychiatry and Psychiatric Epidemiology1989; 24:41–48.
27.
BoscarinoJAPost-traumatic stress and associated disorders among Vietnam veterans: the significance of combat exposure and social support. Journal of Traumatic Stress1995; 8:317–336.
28.
WorthingtonERDemographic and pre-service variables as predictors of post-military service adjustment. In: FigleyCR, ed. Trauma and its wake: the study and treatment of post-traumatic stress disorder. New York: Brunner/Mazel, 1985.
29.
FryeJSStocktonRADiscriminant analysis of post-traumatic stress disorder among a group of Vietnam veterans. American Journal of Psychiatry1982; 139:52–56.
30.
PenkWERobinowitzRRobertsWRPatersonETDolanMPAtkinsHGAdjustment differences among male substance abusers varying in degree of combat exposure in Vietnam. Journal of Consulting and Clinical Psychology1981; 49:426–437.
31.
SolomonZ.The effect of combat-related posttraumatic stress disorder on the family. Psychiatry1988; 51:323–329.
32.
SolomonZKotlerMMikulincerM.Combat-related posttraumatic stress disorder among second-generation holocaust survivors: preliminary findings. American Journal of Psychiatry1988; 145:865–868.
33.
JordanBKMarmarCRFairbankJAProblems in families of male Vietnam veterans with posttraumatic stress disorder. Journal of Consulting and Clinical Psychology1992; 60:916–926.
34.
TrueWRRiceJEisenSAA twin study of genetic and environmental contributions to liability for posttraumatic stress symptoms. Archives of General Psychiatry1993; 50:257–264.
35.
O'TooleBIMarshallRPGraysonDAThe Australian Vietnam veterans health study. I. Study design and response bias. International Journal of Epidemiology1996; 25:307–318.
36.
O'TooleBIMarshallRPGraysonDAThe Australian Vietnam veterans health study. II. Self reported heath of veterans compared with the Australian population. International Journal of Epidemiology1996; 25:319–330.
37.
O'TooleBIMarshallRPGraysonDAThe Australian Vietnam veterans health study. II. Psychological health of Australian Vietnam veterans and its relationship to combat. International Journal of Epidemiology1996; 25:331–340.
38.
O'TooleBIMarshallRPGraysonDASchureckRJPosttraumatic stress disorder and comorbidity in Australian Vietnam veterans: risk factors, chronicity and combat. Australian and New Zealand Journal of Psychiatry1998; 32:32–42.
39.
Australian Bureau of Statistics.Health interview survey, 1989–1990. Canberra: Australian Bureau of Statistics, 1991.
40.
SpitzerRWilliamsJGibbonM.Structured clinical interview for DSM-III-R, version NP-V. New York: New York State Psychiatric Institute, Biometrics Research Department, 1987.
41.
RobinsLNHelzerJEHesselbrookMWishE.The National Institute of Mental Health Diagnostic Interview Schedule: its history, characteristics, and validity. Archives of General Psychiatry1981; 38:381–389.
42.
ForcierLHudsonMFettMJThe mortality report. Vol. III. The relation between aspect of Vietnam service and subsequent mortality among Australian National Servicemen of the Vietnam conflict era. Canberra: Australian Government Publishing Service, 1984.
43.
FettMJDunnMAdenaMAO'TooleBIForcierL.The mortality report. Vol. I. A retrospective cohort study of mortality among Australian National Servicemen of the Vietnam conflict era, and an executive summary of the mortality report. Canberra: Australian Government Publishing Service, 1984.
44.
O'TooleBIAdenaMAFettMJThe mortality report. Vol. II. Factors influencing mortality rates of Australian National Servicemen of the Vietnam conflict era. Canberra: Australian Government Publishing Service, 1984.
45.
MarmarCRWeissDSSchlengerWEPeritraumatic dissociation and posttraumatic stress in male Vietnam theatre veterans. American Journal of Psychiatry1944; 151:902–907.
46.
O'TooleBIAdenaMAJonesMPRisk factors for mortality in Australian Vietnam-era National Servicemen: a case-control study. Community Health Studies1988; XII:408–417.
47.
O'TooleBIIntelligence and motor vehicle mortality. Accident Analysis Prevention1990; 22:211–221.
48.
O'TooleBICantorC.Risk factors for post-war suicide in Australian conscripts of the Vietnam conflict era. Suicide and Life Threatening Behaviour1995; 24:474–487.
49.
O'TooleBIAustralian Veterans health studies pilot study report. A report into the feasibility of an epidemiological investigation of morbidity in Vietnam veterans. Canberra: Australian Government Publishing Service, 1983.
50.
MilesDWWilkesWLLesterDWHutchinsWAThe efficiency of high-speed screening procedures in detecting the neuropsychiatrically unfit at a US Marine Corps Recruit Training Depot. Journal of Psychology1946; 21:243–268.
51.
EysenckHJEysenckSBManual of the Eysenck Personality Questionnaire. London: Hodder and Staughton, 1975.
52.
SPSS Inc.Statistical Package for Social Sciences [computer program]. Version 6.0. Chicago: SPSS, 1989.
53.
CoughlinSSRecall bias in epidemiologic studies. Journal of Clinical Epidemiology1990; 43:87–91.
54.
SimonGEvon KorffM.Re-evaluation of secular trends in depression rates. American Journal of Epidemiology1992; 135:1411–1422.
55.
van der KolkBAAdolescent vulnerability to posttraumatic stress disorder. Psychiatry1985; 48:365–370.
56.
FettMJAdenaMACobbinDMDunnM.Mortality among Australian conscripts of the Vietnam conflict era. I. Death from all causes. American Journal of Epidemiology1987; 125:869–877.
57.
FettMJNairnJRCobbinDMAdenaMAMortality among Australian conscripts of the Vietnam conflict era. II. Causes of death. American Journal of Epidemiology1987; 125:878–884.
