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Suggested Citation:"3 Available Datasets." Institute of Medicine. 2008. Epidemiologic Studies of Veterans Exposed to Depleted Uranium: Feasibility and Design Issues. Washington, DC: The National Academies Press. doi: 10.17226/12200.
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Suggested Citation:"3 Available Datasets." Institute of Medicine. 2008. Epidemiologic Studies of Veterans Exposed to Depleted Uranium: Feasibility and Design Issues. Washington, DC: The National Academies Press. doi: 10.17226/12200.
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Suggested Citation:"3 Available Datasets." Institute of Medicine. 2008. Epidemiologic Studies of Veterans Exposed to Depleted Uranium: Feasibility and Design Issues. Washington, DC: The National Academies Press. doi: 10.17226/12200.
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Suggested Citation:"3 Available Datasets." Institute of Medicine. 2008. Epidemiologic Studies of Veterans Exposed to Depleted Uranium: Feasibility and Design Issues. Washington, DC: The National Academies Press. doi: 10.17226/12200.
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Suggested Citation:"3 Available Datasets." Institute of Medicine. 2008. Epidemiologic Studies of Veterans Exposed to Depleted Uranium: Feasibility and Design Issues. Washington, DC: The National Academies Press. doi: 10.17226/12200.
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Suggested Citation:"3 Available Datasets." Institute of Medicine. 2008. Epidemiologic Studies of Veterans Exposed to Depleted Uranium: Feasibility and Design Issues. Washington, DC: The National Academies Press. doi: 10.17226/12200.
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Suggested Citation:"3 Available Datasets." Institute of Medicine. 2008. Epidemiologic Studies of Veterans Exposed to Depleted Uranium: Feasibility and Design Issues. Washington, DC: The National Academies Press. doi: 10.17226/12200.
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Suggested Citation:"3 Available Datasets." Institute of Medicine. 2008. Epidemiologic Studies of Veterans Exposed to Depleted Uranium: Feasibility and Design Issues. Washington, DC: The National Academies Press. doi: 10.17226/12200.
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Suggested Citation:"3 Available Datasets." Institute of Medicine. 2008. Epidemiologic Studies of Veterans Exposed to Depleted Uranium: Feasibility and Design Issues. Washington, DC: The National Academies Press. doi: 10.17226/12200.
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Suggested Citation:"3 Available Datasets." Institute of Medicine. 2008. Epidemiologic Studies of Veterans Exposed to Depleted Uranium: Feasibility and Design Issues. Washington, DC: The National Academies Press. doi: 10.17226/12200.
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Suggested Citation:"3 Available Datasets." Institute of Medicine. 2008. Epidemiologic Studies of Veterans Exposed to Depleted Uranium: Feasibility and Design Issues. Washington, DC: The National Academies Press. doi: 10.17226/12200.
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Suggested Citation:"3 Available Datasets." Institute of Medicine. 2008. Epidemiologic Studies of Veterans Exposed to Depleted Uranium: Feasibility and Design Issues. Washington, DC: The National Academies Press. doi: 10.17226/12200.
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Suggested Citation:"3 Available Datasets." Institute of Medicine. 2008. Epidemiologic Studies of Veterans Exposed to Depleted Uranium: Feasibility and Design Issues. Washington, DC: The National Academies Press. doi: 10.17226/12200.
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Suggested Citation:"3 Available Datasets." Institute of Medicine. 2008. Epidemiologic Studies of Veterans Exposed to Depleted Uranium: Feasibility and Design Issues. Washington, DC: The National Academies Press. doi: 10.17226/12200.
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Suggested Citation:"3 Available Datasets." Institute of Medicine. 2008. Epidemiologic Studies of Veterans Exposed to Depleted Uranium: Feasibility and Design Issues. Washington, DC: The National Academies Press. doi: 10.17226/12200.
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Suggested Citation:"3 Available Datasets." Institute of Medicine. 2008. Epidemiologic Studies of Veterans Exposed to Depleted Uranium: Feasibility and Design Issues. Washington, DC: The National Academies Press. doi: 10.17226/12200.
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Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

3 Available Datasets The information described in this chapter represents the committee’s under- standing about available sources of data on health outcomes in military personnel and veterans exposed to depleted uranium (DU) that might be useful for future study of this population. The chapter discusses the committee’s evaluation of the available datasets and their limitations. DEPLETED-URANIUM EXPOSURE IN THE MILITARY POPULATION DU munitions and armor were extensively used by the US military during the 1991 Gulf War, and military personnel were first exposed to DU as a result of friendly-fire incidents, cleanup and salvage operations, and proximity to burning DU-containing tanks and ammunition (DOD, 2000). In an effort to character- ize exposures to DU, the Department of Defense (DOD) Office of the Special Assistant for Gulf War Illnesses developed three levels of exposure scenarios (DOD, 2000): • Level I exposure. This highest exposure level occurred when soldiers were in or near combat vehicles when they were struck by DU rounds or entered vehicles soon after the impact. It is estimated that 134-164 people may have experienced level I exposure. The Depleted Uranium Follow-Up Program at the Baltimore Veterans’ Affairs Medical Center has provided clinical surveillance of Gulf War veterans who were exposed to DU through friendly-fire incidents. • Level II exposure. This intermediate level of exposure occurred when soldiers and civilian employees worked on DU-contaminated vehicles or were 25

26 FEASIBILITY AND DESIGN OF STUDIES OF DU-EXPOSED VETERANS involved in cleanup efforts after a 1991 fire at Camp Doha in Kuwait. More than 700 people may have experienced level II exposure (Kilpatrick, 2008). • Level III exposure. This lowest level of exposure occurred when troops were downwind of burning DU ammunition, DU-contaminated vehicles, or the Camp Doha fire, or when they entered DU-contaminated Iraqi tanks. DOD estimates that thousands of people may have experienced level III exposure (Kilpatrick, 2008). DU-containing weapons systems have been used in the military operations that began in Iraq in 2003 (Operation Iraqi Freedom, OIF), and there is potential for exposure of military personnel to DU in that war theater as well. AVAILABLE DATASETS Discussed below are select available datasets that are being used to track exposure of and health outcomes in military and veteran populations. Some were developed to study long-term health outcomes in general (for example, that of the Millennium Cohort Study), and others were designed to assess DU exposure and health outcomes specifically (for example, that of the Depleted Uranium Follow-Up Program). In most cases, some component was designated to record environmental exposure. The limitations of the datasets are discussed below. Information about each dataset is summarized in Table 3-1. Department of Defense Depleted Uranium Medical Management Program DOD’s Depleted Uranium Medical Management Program is a component of the overall health-surveillance program for military personnel returning from deployment. The program includes identifying DU-exposed OIF military person- nel both by identifying events involving DU munitions or other DU-containing materials that may have resulted in internal exposure and through the postde- ployment health-assessment process and patients’ self-reporting of DU exposure to medical personnel. A testing program for collecting urine to monitor for DU exposure is in place, and the Depleted Uranium Follow-Up Program provides continuing health monitoring of military personnel exposed to DU during the 1991 Gulf War and OIF. Several DOD policies provide guidance on identifying DU-exposed mili- tary personnel, quantifying and documenting exposures, analyzing embedded fragments, referring military personnel and veterans to the Depleted Uranium Follow-Up Program, and reporting and archiving bioassay results (DOD, 2003, 2004a,b, 2008c).

TABLE 3-1  Information in Available Datasets Datasets PDHA (Form 2796) and Depleted Uranium Follow-Up Reassessment (Form 2900), Critical Elements Program DU Questionnaire (Form 2872) Millennium Cohort Study Birth and Infant Health Registry Study design Case series, clinical surveillance Survey (continuing activity) Prospective cohort Registry Study population <100 male Gulf War veterans PDHA/reassessment: >900,000 >100,000 military >750,000 infants born in 1998- +3 male OIF personnel (as of OIF personnel, of whom personnel (active duty, 2004 to military families (those February 2008) 27,000 reported potential DU reserve) with DOD health-care benefits) exposure Panel 1: 77,047 people Followup DU questionnaire: (9,251 Gulf War veterans) about 1,200 OIF personnel Panel 2: 31,110 people (about another 1,200 received Panel 3: about 40,000 urinalysis but did not fill out people (panel being DU questionnaire) recruited as of February 2008) Study population will be followed for up to 21 years Exposure assessment for DU Biomonitoring Yes, urinalysis Yes, urinalysis for 2,447 OIF No No conducted? personnel Also measure seminal and blood uranium 27 continued

TABLE 3-1  Continued 28 Datasets PDHA (Form 2796) and Depleted Uranium Follow-Up Reassessment (Form 2900), Critical Elements Program DU Questionnaire (Form 2872) Millennium Cohort Study Birth and Infant Health Registry Work records Yes, veterans and military Yes, primary-care manager No Parental demographic, military (assignment and personnel with level I exposure may review work records to exposure data available from location) evaluated? included in study determine DU exposure (level DEERS, DMDC I, II, or III) Self-report data Yes Yes, PDHA and reassessment, Yes, participants fill out No collected? DU questionnaire surveys in 3-year intervals to assess physical, mental- health status Participants asked whether they had been exposed to DU during previous 3 years Health-outcome assessment Mortality recorded? Yes No, but could be in future Yes, recorded for study NA duration; could be linked to National Death Index periodically

Morbidity recorded? Yes, following are assessed: Yes, PDHA and reassessment Yes, self-reported NA hematologic measures, renal ask about general health markers, semen measures, Data could be validated by reproductive endocrine In addition to form, there is additional data collection measures, neurocognitive face-to-face assessment with effects, chromosomal measures trained health-care provider, clinical validation of disease Clinical surveillance and monitoring Adverse outcome in Yes No No Yes (for first year of life among offspring recorded? live births) Controlling of Adjusted for age, race, NA Controlled for sex, age, NA confounders and bias? education, intelligence, education, marital status, smoking, marital status, military race or ethnicity, short- rank, exposure to genetic and long-term service, toxicants, depression, use of deployment status, pay prescription psychotropic and grade, active-duty status, antidepressant drugs, recent service branch, occupation x-ray exposure Adequate followup Population followed since 1993 NA Population has been Data collected since 1998 period? followed since 2001 Study continues Study continues Study continues Analytic approach and Case series with longitudinal Retrospective analysis Longitudinal analysis Descriptive data analysis followup 29 continued

TABLE 3-1  Continued 30 Datasets PDHA (Form 2796) and Depleted Uranium Follow-Up Reassessment (Form 2900), Critical Elements Program DU Questionnaire (Form 2872) Millennium Cohort Study Birth and Infant Health Registry Limitations Small population Self-reported exposure Small sample of those Limited to live births; no potentially exposed information on early pregnancy Level I exposure only Small sample, low statistical losses, stillbirths, abortions power Lacks sufficient statistical Lacks sufficient statistical power Registry does not follow infants power past first year of age, may not Recall bias related to capture important defects or self-reporting of previous diseases that occur after that exposure Severity of effects not captured Potential for in ICD-9-CM codes misclassification of exposure Not designed to assess birth defects associated with Self-selected population exposure to DU; no information on parental exposure to DU Use of standard instruments as surrogate Limited to active-duty military for clinical diagnosis in military-health system. Small number of subjects; lacks statistical power to detect effect Corroboration of Yes Yes Could be done if Could be done through linkage biomonitoring data with biomonitoring data were with other DOD databases work record or self- collected reported data? NOTE: DEERS = Defense Enrollment Eligibility Reporting System, DMDC = Defense Manpower Data Center, DOD = Department of Defense, DU = depleted uranium, ICD-9-CM = International Classification of Diseases, 9th edition, NA = not available, OIF = Operation Iraqi Freedom, PDHA = postdeployment health assessment.

AVAILABLE DATASETS 31 Depleted Uranium Follow-Up Program The Depleted Uranium Follow-Up Program, established in 1993, has pro- vided clinical surveillance of veterans of the 1991 Gulf War who were exposed to DU through friendly-fire incidents (level I exposure). During the course of the Gulf War conflict, soldiers in or on vehicles and tanks “were mistakenly fired on and struck by munitions containing DU” (McDiarmid et al., 2000) and are thought to have inhaled or ingested DU particles, experienced wound contami- nation by DU, or received multiple tiny fragments of DU scattered throughout muscle and soft tissue. The medical-surveillance program was designed to assess health effects in veterans exposed to DU and to evaluate techniques for measuring uranium (McDiarmid, 2007). Study Population.  Since the inception of the program, researchers have pro- spectively evaluated about 70 of the estimated 100 Gulf War veteran survivors of friendly-fire incidents (McDiarmid et al., 2006). In 1998, DOD and the Department of Veterans Affairs (VA) began offer- ing DU medical screening to any other Gulf War veterans concerned about DU exposure. The screening included 30 questions about exposure and a 24-hour urine collection (Kilpatrick, 2008). From 1998 to 2002, about 400 veterans were enrolled in the voluntary program. Their median urinary uranium concentra- tion was 0.01 µg/g of creatinine. Three of the veterans had higher than normal uranium concentrations. Researchers noted that only one of the 30 exposure questions (which was related to embedded metal fragments) was predictive of increased uranium concentration (Kilpatrick, 2008). The three veterans with increased uranium concentrations were enrolled in the Depleted Uranium Follow- Up Program. More recently, OIF military personnel and veterans with confirmed DU ex- posure have been enrolled in the Depleted Uranium Follow-Up Program (see dis- cussion of the postdeployment health-assessment program below) (McDiarmid, 2007). Assessment of Exposure and Outcomes.  The surveillance protocol consists of a detailed questionnaire documenting medical history, socioeconomic back- ground, and occupational exposure; clinical testing, including hematologic and blood clinical-chemistry measures, urinalysis, seminal and blood uranium, renal markers, semen analysis, and reproductive endocrine measures; neurocognitive testing; and chromosomal analysis (McDiarmid et al., 2001). Thirty-three veterans were initially examined in 1993-1994. Nearly half were confirmed as having uranium fragments embedded in a number of loca- tions throughout their soft tissue. They also had much higher mean urinary uranium concentrations than those without retained fragments (4.47 vs 0.03 µg/g of creatinine); no other abnormalities were detected (McDiarmid et al., 2000).

32 FEASIBILITY AND DESIGN OF STUDIES OF DU-EXPOSED VETERANS The cohort has been examined every 2 years to assess functioning of the major target organ systems (primarily the kidneys, the central nervous system, and the reproductive system). Continuous evaluation of the cohort since 1993 has yielded a number of studies to assess outcomes related to exposure. There have been no clinically significant findings of health outcomes related to exposure to DU, and researchers found no major birth defects in the 70 children born to the veterans in the cohort (McDiarmid et al., 2007; Kilpatrick, 2008). Limitations.  The Depleted Uranium Follow-Up Program is a well-designed sur- veillance program that has adequately captured information on a set of veterans of the Gulf War and OIF with level I exposure. However, the program does not constitute a comprehensive epidemiologic study of veterans exposed to DU in that the study population is small (so statistical power is low) and includes only those who were determined to have level I exposure. Postdeployment Health Assessment DOD administers a postdeployment health assessment (PDHA) to all service members returning from OIF. The PDHA includes a face-to-face assessment with a trained health-care provider and a detailed questionnaire. The purpose of the PDHA is to “review each service member’s current health, mental health, or psychosocial issues commonly associated with deployments, special medica- tions taken during the deployment, possible deployment-related occupational/ environmental exposures, and to discuss deployment-related health concerns” (DOD, 2008a). The questionnaire includes a variety of questions related to health outcomes and exposure to environmental contaminants during deployment. The standard PDHA questionnaire includes date of birth, sex, service branch, mari- tal status, location of operation, total deployments in preceding 5 years, rating of overall health, number of times a health-care provider was consulted, injury during deployment, deployment-related conditions, family conflicts, alcohol con- sumption, and mental-health concerns (DOD, 2008a). Regarding exposure to DU, question 16 on the form asks: “Are you worried about your health because you were exposed to: Depleted uranium?” with a pos- sible response of either “yes” or “no.” Question 18 asks: “Did you enter or closely inspect any destroyed military vehicles?” If the veteran marks “yes” to question 16 (related to DU exposure) or question 18 and the health-care provider deems that there may be “potential exposure to depleted uranium,” the veteran will be referred to the primary-care manager for completion of the DU questionnaire (Form 2872; see below) and a possible 24-hour urinalysis. DOD also identifies people with potential exposure by using Form 2900 (January 2008) “Post-Deployment Health Re-Assessment.” That form includes

AVAILABLE DATASETS 33 a question about possible exposure to DU. Question 10 asks: “Do you have any persistent major concerns regarding the health effects of something you believe you may have been exposed to or encountered while deployed?” One possible response is “depleted uranium” (DOD, 2008b). Form 2872, “Depleted Uranium (DU) Questionnaire,” asks nearly 50 ques- tions, including specific questions about location of service and whether the person may have been exposed at Camp Doha at the time of the fire in 1991, was involved in cleanup operations or entered a tank or Bradley fighting vehicle to perform rescue, was hit by friendly fire, was exposed to smoke, or had other concerns about exposure. On the basis of the exposure information provided on the DU questionnaire, the health-care provider assigns the person to one of the three exposure levels (I, II, or III). The results of a urine bioassay can also be recorded on the form. For those with potential level I or II exposure, bioassays are required. Although a bioassay is not required for someone with level III ex- posure, health-care providers may provide testing if requested by the person or if there are medical concerns about exposure. Bioassays must be performed as soon as possible, preferably within 180 days after exposure, but should be conducted even if more than 180 days have elapsed since exposure. Twenty-four-hour urine samples are collected to determine uranium concentration. If the person reports potential exposure while in theater and a 24-hour sample is not possible, a spot urine sample is collected. In addition, a 24-hour sample must be collected 7-10 days after exposure if the initial 24-hour sample was collected 24-48 hours after exposure. If a urine sample is high in uranium (total uranium concentration at least 50 ng/g of creatinine) or isotopic analysis indicates the presence of DU at 10% or more of total uranium and/or the person has embedded fragments or fragment- type injuries, he or she is referred to the Depleted Uranium Follow-Up Program (see above). If the results of the urinary-uranium test and the isotopic analysis are high and there is no evidence of embedded fragments in the radiologic skeletal survey, the person may also be referred to the program. As of September 30, 2007, 2,447 OIF military personnel had been tested (Casscells, 2008). The tests were performed within days to a few months after their return from theater. Of the 2,447 tested, 10 had confirmed detection of DU in their urine (see Table 3-2). The 10 were found to have retained metal frag- ments or had recently had fragments removed. Three of the 10 were enrolled in the Depleted Uranium Follow-Up Program (Kilpatrick, 2008). Limitations.  There are a number of limitations in the data available through this program. Exposures are largely self-reported, although there is opportunity to follow up with urine samples. The sample is small and does not permit adequate statistical power to detect most health outcomes.

34 FEASIBILITY AND DESIGN OF STUDIES OF DU-EXPOSED VETERANS TABLE 3-2  Summary of DU Bioassay Results (2003-2007) Navy and Air Depleted Uranium Exposure Level Army Marines Force Total Detected in Urine I 244 71 2 317 8 II 464 98 10 572 0 III 244 85 8 337 0 Uncategorized 1,208 13 0 1,221 2 TOTAL 2,160 267 20 2,447 10 SOURCE: Adapted from Casscells, 2008. Millennium Cohort Study Launched in 2001, the Millennium Cohort Study is the largest prospective health study in military history. The study was established in response to a DOD recommendation for a long-term study of deployment-related exposure and an Institute of Medicine report (IOM, 1999) recommendation for a longitudinal population-based study of the health of service members (Ryan et al., 2007). The objective of the study is to “evaluate the impact of military service, includ- ing deployments and other occupational exposures, on long-term health” (DOD Center for Deployment Health Research, 2007). Chronic health outcomes—such as hypertension, heart disease, diabetes, and other multisymptom illnesses—are a major focus of the study. Study Population The study began its phased enrollment process in 2001 with the hope of en- rolling a representative sample of over 100,000 US military personnel, including active-duty and reserve members. Participants would be followed for up to 21 years and researchers planned to resurvey participants in 3-year intervals until at least 2022. Three panels have been or are being recruited. Panel 1, recruited in 2001, has 77,047 members; 9,251 (12%) had been deployed in the 1991 Gulf War (B. Smith, personal communication, February 14, 2008). Panel 1 includes randomly selected service members; the researchers also oversampled female reservists for this panel. Panel 2, recruited in 2004, has 31,110 members, again randomly sampled but with an effort to oversample women. Panel 3, which is be- ing recruited, will have about 40,000 members, and women will be oversampled. Enrollment into Panel 3 is being conducted through mailed surveys and electroni- cally (Smith, 2008). Assessment of Exposure and Outcomes The survey instruments for the first phased enrollment included over 450 questions to collect such information as symptoms, psychosocial status, physical

AVAILABLE DATASETS 35 and functional status, occupation, military exposure, demographic information, and use of alcohol and drugs. The study uses standardized instruments to collect data, including the Primary Care Evaluation of Mental Disorders (PRIME-MD) Patient Health Questionnaire (used to assess psychologic disorders), Medical Outcomes Study short form-46 for veterans (used to assess functioning, pain, general health, and mental disorders), the CAGE questionnaire to assess alcohol problems, the Posttraumatic Stress Disorder Checklist-Civilian Version, and a VA Gulf War survey of specific wartime exposure, including exposure to DU (Ryan et al., 2007). As mentioned above, subjects will be surveyed triennially, and results will be linked to other large databases, including deployment data, data from VA, and pharmacologic data. Researchers are also planning to link survey results to data from DOD Serum Repository data, civilian inpatient and outpatient care data, and the DOD Birth and Infant Health Registry. Environmen- tal exposure will be assessed by using the US Army Center for Health Promotion and Preventive Medicine’s air, soil, and water sampling data (Smith, 2008). Burden of Depleted Uranium in Study Population Regarding exposure to DU, participants in the study were asked whether they had been exposed to DU during the preceding 3 years. Participants had the option to indicate “yes,” “no,” or “don’t know.” In Panel 1 of the cohort, 2,823 people marked “yes” for having been exposed to DU in the preceding 3 years. Of the 9,251 Gulf War veterans (12%) enrolled in Panel 1, 558 (6%) reported “yes” to DU exposure during the previous 3 years, 961 (10.4%) reported “don’t know,” 7,584 (82%) reported “no,” and 148 (1.6%) did not answer the question. Limitations The Millennium Cohort study population is not ideal for evaluating health effects related to DU exposure, because it was not designed to assess specifically this relatively rare exposure. Although the intent is to enroll 100,000 study par- ticipants, the number reporting DU exposure is quite low and may be reduced if biomonitoring data indicate that even fewer have confirmed exposure. The study also lacks sufficient statistical power to assess exposure to DU and related health outcomes. In addition, administering a self-reported survey that asks participants to recall exposure to DU without specific followup questions about conditions where exposure may have occurred is problematic. Exposure to DU in the Gulf War theater will not be captured in veterans who respond “yes” on being asked about being exposed to DU, because the question focuses on exposures during   Thisnumber is not limited to Gulf War veterans and includes all those in Panel 1 who responded “yes” when asked whether they had been exposed to DU in the preceding 3 years.

36 FEASIBILITY AND DESIGN OF STUDIES OF DU-EXPOSED VETERANS the 3 years before 2001 (the questionnaire was administered in 2001). The time since potential Gulf War exposure is substantial and may introduce recall bias and misclassification of exposure in this population. The investigators also acknowledge a number of study limitations, including the following: the study includes a self-selected population (the respondents) that may not be representative of all military personnel or those who are deployed, there is a potential for recall bias due to self-reporting of exposure, service mem- bers who are already ill may decline to participate, and the use of surveys as a surrogate for clinical diagnosis of illness may be inaccurate (Smith, 2008). Department of Defense Birth and Infant Health Registry The assistant secretary of defense for health affairs established the Birth and Infant Health Registry in 1998 in response to a Senate Committee on Veterans’ Affairs recommendation to establish a birth-defects registry for military service members. The registry collects data on birth and health outcomes in infants born into military families. Study Population The registry focuses specifically on families enrolled in the DOD health-care program, and the children are followed up to the age of 1 year. The infants were born in all 50 states and Washington, DC, and abroad. As of 2001, 39% of the DOD births were to Army personnel, 25% to Air Force personnel, 24% to Navy personnel, 11% to Marine Corps personnel, and 3% to Coast Guard or other service personnel; at that time, fewer than 19% of the births were to active-duty mothers (Ryan et al., 2001). Assessment of Exposure and Outcomes The registry draws on a number of large datasets. Births and diagnoses are captured from inpatient and outpatient data by using the following databases: the Standard Inpatient Data Record, the Standard Ambulatory Data Record, and the Health Care Service Record. Demographic data and exposure data on military families are captured by using the Defense Enrollment Eligibility Reporting System and the Defense Manpower Data Center. The registry uses the Interna- tional Statistical Classification of Diseases, Ninth Revision codes in 45 major- malformation categories. On the basis of guidelines established by the National Birth Defects Prevention Network, data are validated to assess overrecording and underrecording of birth defects (Conlin, 2008). The prevalence of birth defects in 1998-2004 was 3-4%. The most com- monly diagnosed defects were atrial septal defect, ventricular septal defect, patent ductus arteriosus, and hypospadias and epispadias. Prevalence was higher with

AVAILABLE DATASETS 37 multiple gestation, male sex, and increasing maternal age (Conlin, 2008). Overall, researchers have found that the prevalence of birth defects in military families is similar to that in the civilian population. The registry is complementary to civilian public-health efforts to collect data on birth defects and in the future may be linked with data on environmental and occupational exposure. Burden of Depleted Uranium in Study Population The burden of DU in the study population has not been studied, but informa- tion may be assessed in the future by linking with other databases. Limitations The investigators acknowledge that the surveillance efforts are limited to live births and do not capture information on early-pregnancy losses, stillbirths, or abortions. In addition, the ICD-9-CM codes are not useful in capturing the sever- ity of effects. Defects or diseases which may be present at birth but not diagnosed until after the age of 1 year are not captured in the registry (Conlin, 2008). Those limitations are common to many birth defects monitoring programs. The registry is not designed to assess birth defects associated with exposure to DU. It is limited to active-duty military in the military health system. It is not designed to assess parental exposure to DU. The number of subjects in the regis- try lacks statistical power to detect an effect related to exposure to uranium. Loss of followup would occur if a parent left military service during the first year. Other Department of Defense Databases DOD maintains numerous health-related databases that can be linked to pro- vide information about health status and potential exposure (Cox, 2007). Select databases are discussed below. The Military Health System (MHS) includes a data repository, personnel tracking, health-care encounter information, and environmental databases. The MHS Data Repository includes comprehensive datasets from a variety of sources (including information about medical treatment, pharmacy information, and de- mographic data) that can be exported for analysis. Other MHS databases include the Defense Occupational and Environmental Health Readiness System, the DU testing archive (contains results of all urine testing for DU), the Master Death File, the DOD Mortality Registry, and the Medical Evaluation Board database. Many of the databases track deployment-related information, such as in-theater health-care data and environmental-hazard identification and exposure data. Re- garding available environmental- and occupational-exposure data, DOD notes that most of the data are not available in real time but must be entered manually

38 FEASIBILITY AND DESIGN OF STUDIES OF DU-EXPOSED VETERANS and that sampling capabilities depend on the reporting site. It is possible to link personnel, medical, serologic, and deployment data. The DOD Medical Mortality Registry, administered by the Armed Forces Medical Examiner System, provides real-time notification of fatalities during active duty (Cox, 2007). SUMMARY This chapter summarizes several programs and datasets that are available to study the health of military and veteran populations. Some are designed spe- cifically to assess DU exposure and health outcomes; others are tracking health outcomes in general but might be useful in further study of DU-exposed military and veteran populations. Examples of limitations of the datasets are inadequate sample size and statistical power, inadequate exposure assessment, and substan- tial potential for recall bias and exposure misclassification. REFERENCES Casscells, S. W. 2008. Operation Iraqi freedom depleted uranium bioassay results—eighth semian- nual report and request for data submission for ninth semiannual report. Falls Church, VA: TRICARE Management Activity. Conlin, A. M. 2008 (unpublished). The Department of Defense (DOD) birth and infant health registry. Presentation to the IOM committee on Gulf War and health: Depleted uranium. San Diego, CA: Department of Defense Center for Deployment Health Research, Naval Health Research Center. Available: National Academies’ Public Access Records Office (publicac@nas.edu). Cox, K. L. 2007 (unpublished). Department of Defense health data sets. Presentation to the IOM committee on Gulf War and health: Depleted uranium. Washington, DC: Department of Defense Center for Deployment Health Research, Naval Health Research Center. Available: National Academies’ Public Access Records Office (publicac@nas.edu). DOD (Department of Defense). 2000. Environmental exposure report: Depleted uranium in the Gulf (II). Washington, DC: Department of Defense. ———. 2003. HA policy 03-012: Policy for OIF DU medical management. Washington, DC: De- partment of Defense. ———. 2004a. HA policy 04-004, Department of Defense deployment biomonitoring policy and ap- proved bioassays for depleted uranium and lead. Washington, DC: Department of Defense. ———. 2004b (unpublished). Memorandum: Operation Iraqi freedom depleted uranium medical management. Washington, DC: Department of Defense. Available: National Academies’ Public Access Records Office (publicac@nas.edu). ———. 2008a. Enhanced post-deployment health assessment (PDHA) process (DD form 2796). Washington, DC: Department of Defense. ———. 2008b. Post-deployment health reassessment: DD form 2900. Washington, DC: Department of Defense. ———. 2008c. Supplemental information and clinical guidance for DOD depleted uranium (DU) medical management program. Washington, DC: Department of Defense. DOD Center for Deployment Health Research. 2007 (unpublished). The millennium cohort study: Fact sheet. Washington, DC: Department of Defense. Available: National Academies’ Public Access Records Office (publicac@nas.edu). IOM (Institute of Medicine). 1999. Gulf War veterans: Measuring health. Washington, DC: National Academy Press.

AVAILABLE DATASETS 39 Kilpatrick, M. E. 2008 (unpublished). Potential exposures to depleted uranium during the 1991 Gulf War. Presentation to the IOM committee on Gulf War and health: Depleted uranium. Wash- ington, DC: Department of Defense. Available: National Academies’ Public Access Records Office (publicac@nas.edu). McDiarmid, M. 2007 (unpublished). Depleted uranium (DU) follow-up program update. Presenta- tion to the IOM committee on Gulf War and health: Depleted uranium. Baltimore: University of Maryland. Available: National Academies’ Public Access Records Office (publicac@nas. edu). McDiarmid, M. A., J. P. Keogh, F. J. Hooper, K. McPhaul, K. Squibb, R. Kane, R. DiPino, M. Kabat, B. Kaup, L. Anderson, D. Hoover, L. Brown, M. Hamilton, D. Jacobson-Kram, B. Burrows, and M. Walsh. 2000. Health effects of depleted uranium on exposed Gulf War veterans. Envi- ronmental Research 82(2):168-180. McDiarmid, M. A., K. Squibb, S. Engelhardt, M. Oliver, P. Gucer, P. D. Wilson, R. Kane, M. Kabat, B. Kaup, L. Anderson, D. Hoover, L. Brown, and D. Jacobson-Kram. 2001. Surveillance of depleted uranium exposed Gulf War veterans: Health effects observed in an enlarged “friendly fire” cohort. Journal of Occupational and Environmental Medicine 43(12):991-1000. McDiarmid, M. A., S. M. Engelhardt, M. Oliver, P. Gucer, P. D. Wilson, R. Kane, M. Kabat, B. Kaup, L. Anderson, D. Hoover, L. Brown, R. J. Albertini, R. Gudi, D. Jacobson-Kram, C. D. Thorne, and K. S. Squibb. 2006. Biological monitoring and surveillance results of Gulf War I veterans exposed to depleted uranium. International Archives of Occupational and Environ- mental Health 79(1):11-21. McDiarmid, M. A., S. M. Engelhardt, M. Oliver, P. Gucer, P. D. Wilson, R. Kane, A. Cernich, B. Kaup, L. Anderson, D. Hoover, L. Brown, R. Albertini, R. Gudi, D. Jacobson-Kram, and K. S. Squibb. 2007. Health surveillance of Gulf War I veterans exposed to depleted uranium: Updat- ing the cohort. Health Physics 93(1):60-73. Ryan, M. A., M. A. Pershyn-Kisor, W. K. Honner, T. C. Smith, R. J. Reed, and G. C. Gray. 2001. The Department of Defense birth defects registry: Overview of a new surveillance system. Teratol- ogy 64(Suppl 1):S26-S29. Ryan, M. A., T. C. Smith, B. Smith, P. Amoroso, E. J. Boyko, G. C. Gray, G. D. Gackstetter, J. R. Riddle, T. S. Wells, G. Gumbs, T. E. Corbeil, and T. I. Hooper. 2007. Millennium cohort: En- rollment begins a 21-year contribution to understanding the impact of military service. Journal of Clinical Epidemiology 60(2):181-191. Smith, B. 2008 (unpublished). The millennium cohort study. Presentation to the IOM committee on Gulf War and health: Depleted uranium. San Diego, CA: DOD Center for Deployment Health Research, Naval Health Research Center. Available: National Academies’ Public Access Re- cords Office (publicac@nas.edu).

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Epidemiologic Studies of Veterans Exposed to Depleted Uranium: Feasibility and Design Issues Get This Book
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Depleted uranium, a component of some weapons systems, has been in use by the U.S. military since the 1991 Gulf War. Military personnel have been exposed to depleted uranium as the result of friendly fire incidents, cleanup and salvage operations, and proximity to burning depleted uranium-containing tanks and ammunition. Under a Congressional mandate, the Department of Defense sought guidance from the Institute of Medicine in evaluating the feasibility and design of an epidemiologic study that would assess health outcomes of exposure to depleted uranium. The study committee examined several options to study health outcomes of depleted uranium exposure in military and veteran populations and concluded that it would be difficult to design a study to comprehensively assess depleted uranium-related health outcomes with currently available data. The committee further concluded that the option most likely to obtain useful information about depleted uranium-related health outcomes would be a prospective cohort study if future military operations involve exposure to depleted uranium. The book contains recommendations aimed at improving future epidemiologic studies and identifying current active-duty military personnel and veterans with potential DU exposure.

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