veteran population served during the Vietnam War era. However, because the proportion of homeless veterans who served in combat and served in the Vietnam theater was about the same for the veterans who were not homeless, the authors interpreted that finding to suggest that the risk of homelessness could be attributed more to age—that is, being 30-44 years old (an age of specific vulnerability of men to homelessness)—than to combat exposure.
Rosenheck et al. (1992), in a study of the relationship between combat stress and homelessness, compared data on 627 Vietnam veterans who were evaluated in a VA clinical program for homeless mentally-ill veterans with data on Vietnam veterans assessed in a national epidemiologic study. Some 43% of the 627 veterans in the VA program showed evidence of combat stress that was associated with more severe psychiatric and substance-abuse problems.
Wenzel et al. (1993) assessed 343 homeless male veterans receiving treatment for physical, mental, or substance-abuse disorders and compared the long-term homeless (more than 12 months) with the short-term homeless (12 months or less). The long-term homeless were more likely to be white, to have symptoms of mental and substance-abuse disorders, and to have weaker social support.
A 2001-2003 survey of 631 homeless veterans enrolled in a VA clinical demonstration project designed to evaluate a vocational rehabilitation model, found that 31% of the veterans thought that military service had increased their risk of being homeless (Mares and Rosenheck 2004). Among all the homeless veterans, 19% had received hostile or friendly fire in a combat zone. Only 15% of those who did not think that being in the military had increased their risk of homelessness had received such fire, compared with 25% of those who perceived being in the military as a risk factor. Logistic regression showed that each additional childhood problem reported before military life also almost doubled the likelihood of perceiving that military service increased the risk of homelessness.
Gamache et al. (2000), in the only study of homeless women, estimated the proportions of veterans and nonveterans. Subjects were drawn primarily from a program for homeless persons with mental illness, but the results showed that the risk of homelessness overall was 2-4 times greater for veterans than for nonveterans. Although Vietnam-era women were at greatest risk for homelessness in this sample, the study did not distinguish between Vietnam-theater veterans and Vietnam-era veterans.
Tessler et al. (2002) compared homeless veterans with homeless nonveterans; all were enrolled in an outreach program for persons suffering from serious mental illness. The introduction of an all-volunteer military force did not appear to have changed the composition of the adult male homeless population. Similar results had been obtained by Gamache et al. (2001).
The primary and secondary studies reviewed by the committee yielded mixed results with respect to the effect of deployment, particularly combat, on the risk of homelessness in veterans. Of the three primary studies, only one (Rosenheck and Fontana 1994) showed an association between combat exposure and homelessness in Vietnam veterans. The other two studies were equivocal. The secondary studies were also mixed and in general showed that homelessness was related more to the presence of psychiatric disorders than to combat exposure itself. Nevertheless, as the committee concluded in Chapter 6, deployment to a war zone does increase the risk of psychiatric disorders among veterans, so there may be an indirect effect on homelessness.