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The objective is to provide the first estimates of the prevalence of multiple sclerosis (MS) in Alaskan white males including those migrant to and from the state. A case–control cohort design was utilized with a nationwide series of United States (US) veterans service-connected for MS and matched to pre-illness controls who had entered military service between 1960 and 1994. Among 3,758 white male MS cases and their 7,426 controls were 7 MS and 28 controls resident in Alaska at service entry, who provided an adjusted case/control (C/C) risk ratio for developing MS of 0.47 and an estimated prevalence rate of 22/100,000 population, but only 1 of the 7 had also been born in Alaska, for an estimated prevalence rate of 3.2 per 100,000 (95% confidence interval (CI): 0.08–17.80). The other 6 MS patients and their 26 controls, who migrated from another state to Alaska before onset, had an adjusted C/C ratio of 0.44 for a prevalence rate of 20.6 (95% CI: 7.56–44.90), significantly lower than the reported rate of 45.23 per 100,000 for all US white males in 1976. Another 9 MS patients and 7 controls born in Alaska, who had migrated to another state before entering service, provided an adjusted C/C risk ratio for developing MS of 2.44, with a highly significant elevated prevalence rate of 115 per 100,000 (95% CI: 52.6–218.1). In conclusion, these data suggest that Alaska is not a high-risk area for MS and indicate that migration before onset to Alaska from the high-risk coterminous US decreases the risk of MS and the opposite migration increases it. A formal prevalence survey of MS in Alaska is needed to support or refute these findings. [ABSTRACT FROM AUTHOR]

Simian virus 40 (SV40) was an accidental contaminant of vaccines produced in monkey kidney tissue cultures in the 1950s and early 1960s, including a parenteral adenovirus vaccine given to several hundred thousand US military recruits. Detection of SV40 DNA in tumor tissues by some laboratories suggests that SV40 contributes to human cancers. To determine if entry into US Army service during periods of administration of SV40-contaminated adenovirus vaccine was associated with an increased risk of cancer, the authors conducted a case-control study of cancer occurring in male Army veterans who entered service in 1959–1961. Cases of brain tumors (n = 181), mesothelioma (n = 10), and non-Hodgkin’s lymphoma (n = 220) were identified through a Veterans Administration hospital discharge database, as were colon cancer and lung cancer controls (n = 221). Exposure to adenovirus vaccine was assigned on the basis of known periods of adenovirus vaccine administration and dates of Army entry obtained for cancer cases and controls. The odds ratios associated with exposure to SV40-contaminated adenovirus vaccine were 0.81 (95% confidence interval (CI): 0.52, 1.24) for brain tumors, 1.41 (95% CI: 0.39, 5.15) for mesothelioma, and 0.97 (95% CI: 0.65, 1.44) for non-Hodgkin’s lymphoma. These findings do not support a role for SV40 in the development of these cancers. [ABSTRACT FROM AUTHOR]

The role of genetic and shared environmental influences in the association of alcohol with mortality was studied by using the National Academy of Sciences-National Research Council World War II-veteran male twin registry. An epidemiologic questionnaire administered from 1967 through 1969 permitted identification of twin pairs discordant for alcohol consumption. The subsequent 24 years of mortality follow-up yielded data on time and cause of death. Analyzing the first or only death in drinking-discordant pairs, we observed 27 deaths in abstainer twins and 14 deaths in their light- to moderate-drinker cotwins (relative risk [RR] = 1.93). Excess mortality in twin abstainers was also indicated for deaths from cardiovascular diseases (RR = 2.0) and other causes of death excluding cancers (RR = 3.2). The protective effect, however, of light to moderate drinking did not persist in twins who were smokers at baseline. [ABSTRACT FROM AUTHOR]

The article presents an update on the U.S. National Academy of Sciences-National Research Council Twin Registry. It is considered a significant resource for genetic research. The classic twin study deals with the comparison of the experience of monozygous and dizygous twins with regard to some observable characteristic or phenotype. Other twin study designs include the rearing of twins separately and the cotwin control study, in which one twin serves as control for the other. The Registry has been used in various studies, including one on mortality among twins discordant for alcohol consumption.

Following the Gulf War (GW), large numbers of individuals reported illness that they attributed to exposures encountered during the GW deployment. In response, the Department of Veterans Affairs and the Department of Defense established programs and registries for the evaluation and documentation of GW-related illness, We obtained registrants' medical records, which contained information on outpatient encounters during the 1-year period before their GW deployment, to determine whether registrants with multisymptom illness (cases) have patterns of predeployment health care seeking that are different from those of well registrants (controls). We found that subjects had significantly more predeployment outpatient visits than controls, but this varied by type of visit. Although the number of certain types of predeployment outpatient visits is significantly associated with subsequent multisymptom illness, these associations will have limited predictive value. These findings increase our understanding of multisymptom illness, especially its chronic nature, and justify doing additional studies. [ABSTRACT FROM AUTHOR]

The Assessment of Recruit Motivation and Strength (ARMS) Study was conducted at six Military Entrance Processing Sites during 2005-2006. The objectives were to compare morbidity and attrition of Army accessions who exceeded body fat (EBF) accession standards compared to weight for height or body fat qualified (WQ) and to compare among the WQ subset, those who were physically fit as measured by a 5-minute step test compared to unfit. We performed a cost-effectiveness analysis to address both objectives. Analysis was performed by gender with the primary outcomes of musculoskeletal injury and attrition. Results were expressed in terms of cost per year of military service. Sensitivity analysis was performed on probability cost estimates. We found WQ female recruits were $5,141 less expensive per year than EBF female recruits. WQ males were $2,785 less expensive per year of military service than EBF male recruits. Among WQ recruits, fit females were $3,638 and fit males were $10,381 less expensive per year of service than their unfit counterparts. The ARMS step test is a cost-effective method to identify physically fit EBF applicants for accession in weak recruiting environments. It also offers a cost-effective method to reduce poor physical fitness associated morbidity and attrition., (Reprint & Copyright © 2013 Association of Military Surgeons of the U.S.)

Little is known about the performance of clinician-administered structured diagnostic interviews when given under variable levels of examiner training and monitoring. We sought to explore this question. We examined the performance of a self-report questionnaire and a structured clinical interview in the assessment of post-traumatic stress disorder (PTSD) in two community samples of war veterans. One sample was interviewed under standard conditions (N = 372) and the other under unknown and less standardized conditions (N = 420), more closely approximating 'field conditions'. Interview results were used to predict questionnaire-based PTSD status. Kappas, sensitivities, specificities, and positive predictive powers were moderate and of similar magnitude in both samples. Our results suggest that even under uncertain ('field') conditions, clinician-administered structured interviews can produce results comparable to those produced under more tightly controlled conditions., (Copyright (c) 2006 John Wiley & Sons, Ltd.)

In March 1991, U.S. troops detonated the Khamisiyah, Iraq, ammunition depot, possibly releasing two chemical warfare agents, sarin and cyclosarin. The long-term health effects associated with possible exposure to these chemical warfare agents are unknown. This study was undertaken to investigate whether possible exposure was associated with morbidity among Army Gulf War veterans using morbidity data for 5,555 Army veterans who were deployed to the Gulf region. Responses to 86 self-assessed health measures, as reported in the 1995 Department of Veterans Affairs National Health Survey of Gulf War Era Veterans, were evaluated. We found little association between potential exposure and health, after adjustment for demographic variables, and conclude that potential exposure to sarin or cyclosarin at Khamisiyah does not seem to have adversely affected self-perceived health status, as evidenced by a wide range of health measures.

The purpose of this study was to examine the association of notification of potential exposure to chemical warfare agents in the 1991 Gulf War with subsequent self-reported morbidity. The study sample included 1,056 deployed Army Gulf War veterans who responded to the 1995 National Health Survey of Gulf War Era Veterans and who were resurveyed in 2000. One-half of the subjects had been notified of potential exposure to chemical warfare agents and one-half had not. Comparing notified and non-notified subjects, there were no statistically significant differences with respect to bed days, activity limitations, clinic visits, or hospital visits. Among 71 self-reported medical conditions and symptoms, there were 5 statistically significant differences, 4 of which were for lower rates of illness among notified subjects. Our findings contradict the prevailing notion that perceived exposure to chemical warfare agents should be considered an important cause of morbidity among Gulf War veterans.

Objectives: We investigated whether US Army Gulf War veterans who were potentially exposed to nerve agents during the March 1991 weapons demolitions at Khamisiyah, Iraq, are at increased risk of cause-specific mortality., Methods: The cause-specific mortality of 100487 exposed US Army Gulf War veterans was compared with that of 224980 unexposed US Army Gulf War veterans. Exposure was determined with the Department of Defense 2000 plume model. Relative risk estimates were derived from Cox proportional hazards models., Results: The risks of most disease-related mortality were similar for exposed and unexposed veterans. However, exposed veterans had an increased risk of brain cancer deaths (relative risk [RR]=1.94; 95% confidence interval [CI]=1.12, 3.34). The risk of brain cancer death was larger among those exposed 2 or more days than those exposed 1 day when both were compared separately to all unexposed veterans (RR=3.26; 95% CI=1.33, 7.96; RR=1.72; 95% CI=0.95,3.10, respectively)., Conclusions: Exposure to chemical munitions at Khamisiyah may be associated with an increased risk of brain cancer death. Additional research is required to confirm this finding.

Health status was sought for approximately 1600 Korean War veterans who contracted hemorrhagic fever with renal syndrome (HFRS) during deployment to Korea between 1951 and 1953. To determine whether long-term sequelae were present for these individuals, mortality and morbidity data were collected from the Department of Veterans Affairs, the Centers for Medicare and Medicaid Services, the Social Security Administration, and the National Death Index records. Control subjects were selected from military units in Korea with no reported cases of HFRS. Those with HFRS had a slightly higher mortality rate (33.2%) than did noninfected individuals (32.0%), but this difference was not statistically significant. Non-Caucasian cases had significantly higher morbidity rates than did non-Caucasian controls only for transient ischemic attacks (4.8% versus 0%) and diabetes mellitus (19.3% versus 8.1%). In conclusion, HFRS did not increase mortality rates in this cohort but might have had an impact on selected morbidity outcomes.

Context: Age-related macular degeneration (AMD) is the leading cause of irreversible blindness among older individuals in many parts of the world. The relative importance of genes and environment in the etiology of this major public health problem is not well understood., Objective: To investigate the impact of genetic and environmental factors., Participants: Living twins in the National Academy of Sciences-National Research Council World War II Veteran Twin Registry born between 1917 and 1927., Methods: Twins were surveyed for the known presence of macular degeneration. Enrolled twins underwent a standardized examination and fundus photography. Age-related macular degeneration evaluation was completed for 840 elderly male twins, 210 monozygotic and 181 dizygotic complete twin pairs, both concordant and discordant for presence or absence of AMD, and 58 singletons. A bivariate twin model incorporating initial screening ascertainment and age effects was employed to partition variation in liability to AMD and signs of maculopathy into additive genetic, common environment, and unique environment components., Main Outcome Measure: Heritability of AMD grade and signs of maculopathy based on clinical examination and fundus photographs., Results: Of the 840 twins, 331 had no signs of maculopathy and 241 had early signs, while 162 had intermediate AMD and 106 had advanced AMD. Heritability (additive genetic) estimates were significant for overall AMD grade (0.46) and for intermediate (0.67) and advanced (0.71) AMD. Significant unique environmental proportions of variance were also observed for these AMD variables (0.37, 0.19, and 0.24, respectively). Shared or common environmental contributions were not significant (0.05-0.17). For specific macular drusen and retinal pigment epithelial characteristics, significant genetic (0.26-0.71) and unique environmental (0.28-0.64) proportions of variance were detected., Conclusions: Genetic factors play a substantial role in the etiology of AMD and associated macular characteristics, explaining 46% to 71% of the variation in the overall severity of the disease. Environmental factors unique to each twin also contribute to the occurrence of this disease. This quantification of relative genetic and environmental contributions to the development of AMD should guide future research on this important cause of blindness.

We identified 5345 cases of multiple sclerosis (MS) among US veterans who first entered military service between 1960 and 1994, and who were "service-connected" for MS by the Department of Veterans Affairs (VA). Two controls per case were matched on age, date of service entry, and branch of service. Available for service and VA files were demographic and military data for 4951 cases and 9378 controls. Versus white men, relative risk of MS was significantly higher for all women, at 2.99 for whites, 2.86 for blacks, and 3.51 for those of other races. This was a significant increase from our prior series of veterans of World War II and the Korean Conflict, where white women had a relative risk of 1.79. Risk for black men was higher now (0.67 vs 0.44), while other men remained low (0.30 vs 0.22). Residence at service entry in the northern tier of states had a relative risk of 2.02 versus the southern tier, which was significantly less than the 2.64 for the earlier series. Residence by individual state at birth and service entry for white men further supported this decreasing geographic differential. Such marked changes in geography, sex, and race in such a short interval strongly imply a primary environmental factor in the cause or precipitation of this disease.

In a telephone survey of 4,022 military volunteers for a 1955-1975 program of experimental exposures to chemical agents at Edgewood, Maryland, the current health of those exposed to anticholinesterase agents was compared with that of men exposed to no active chemicals (no chemical test) and to two or more other types of chemical agents (other chemical tests). The survey posed questions about general health and about neurological and psychological deficits. There were only two statistically significant differences: volunteers in anticholinesterase agent tests reported fewer attention problems than those in other chemical tests and greater sleep disturbance than those in no chemical tests. In contrast, volunteers who reported exposure to civilian or military chemical agents outside of their participation in the Edgewood program reported many statistically significant adverse neurological and psychological effects, regardless of their experimental exposure. In this study, the health effects of self-reported, nonexperimental exposure, which are subject to recall bias, were greater than the health effects of experimental exposure.

The NAS-NRC Twin Registry is one of the oldest, national population based-twin registries in the United States. It consists of 15,924 white male twin pairs born in the years 1917-1927 (inclusive) both of whom served in the armed forces. The registry, which has been in operation more than 30 years, has collected data from a variety of sources. Records-based, computerized data have come largely from the Department of Veterans Affairs, and there have been three major epidemiologic questionnaires, undertaken roughly every 15 years. Classic twin studies on a variety of medical conditions were the early focus of the registry, which now has a strong focus on chronic disease epidemiology. Work on a DNA specimen bank has been proceeding slowly, but is now a top priority, due to the increasing force of mortality in this twin cohort.

This study reports on over 40 years of mortality follow-up of 40,581 Navy veterans of the Korean War with potential exposure to high-intensity radar. The cohort death rates were compared with mortality rates for White US men using standardized mortality ratios, and the death rates for men in occupations considered a priori to have high radar exposure were compared with the rates for men in low-exposure occupations using Poisson regression. Deaths from all diseases and all cancers were significantly below expectation overall and for the 20,021 sailors with high radar exposure potential. There was no evidence of increased brain cancer in the entire cohort (standardized mortality ratio (SMR) = 0.9, 95% confidence interval (CI): 0.7, 1.1) or in high-exposure occupations (SMR = 0.7, 95% CI: 0.5, 1.0). Testicular cancer deaths also occurred less frequently than expected in the entire cohort and high-exposure occupations. Death rates for several smoking-related diseases were significantly lower in the high-exposure occupations. Nonlymphocytic leukemia was significantly elevated among men in high-exposure occupations but in only one of the three high-exposure occupations, namely, electronics technicians in aviation squadrons (SMR = 2.2, 95% CI: 1.3, 3.7). Radar exposure had little effect on mortality in this cohort of US Navy veterans.