A co-twin control study of the effects of the vietnam war on the self-reported physical health of veterans

This study examines the impact of military service on 13 categories of self-reported physical health problems by using a sample of 2, 260 American male-male monozygotic twin pairs who served on active duty during the Vietnam War. Data were collected in 1987 by using mail and/or telephone interviews. Twins who served in Southeast Asia reported an increased prevalence of currently having hearing problems (odds ratio (OR) = 1.9, 95% confidence interval (Cl) 1.3-2.7) and persistent skin conditions (OR = 2.1, 95% Cl 1.4-3.2). Odds ratios for these health problems increased with increasing combat exposure and could not be explained by confounding due to posttraumatic stress disorder or demographic or military service factors. Significantly increased odds ratios were also demonstrated for ever having hearing problems (OR = 1.8, 95% Cl 1.3-2.5), ever having persistent skin conditions (OR = 2.1, 95% Cl 1.5-3.0), and having been hospitalized for stomach conditions (OR = 2.6, 95% Cl 1.4-4.9). Marginally increased odds ratios were demonstrated for ever having stomach conditions (OR = 1.4, 95% Cl 1.0-1.9) and urinary conditions (OR = 1.5, 95% Cl 1.0-2.1). Service in Southeast Asia was not associated with any of the remaining categories of physical health problems. Thus, although the past health of veterans who served in Southeast Asia may have been somewhat worse than that of their siblings who did not serve in southeast Asia, no major differences in current health are detected. Am J Epidemiol 1991; 134: 49-58.