Abstract

The effect of military deployments to combat environments on disordered eating and weight changes is unknown. Using longitudinal data from Millennium Cohort Study participants who completed baseline (2001–2003) and follow-up (2004–2006) questionnaires (n = 48,378), the authors investigated new-onset disordered eating and weight changes in a large military cohort. Multivariable logistic regression was used to compare these outcomes among those who deployed and reported combat exposures, those who deployed but did not report combat exposures, and those who did not deploy in support of the wars in Iraq and Afghanistan. Deployment was not significantly associated with new-onset disordered eating in women or men, after adjustment for baseline demographic, military, and behavioral characteristics. However, in subgroup comparison analyses of deployers, deployed women reporting combat exposures were 1.78 times more likely to report new-onset disordered eating (95% confidence interval: 1.02, 3.11) and 2.35 times more likely to lose 10% or more of their body weight compared with women who deployed but did not report combat exposures (95% confidence interval: 1.17, 4.70). Despite no significant overall association between deployment and disordered eating and weight changes, deployed women reporting combat exposures represent a subgroup at higher risk for developing eating problems and weight loss.

The prevalence of eating disorders such as bulimia nervosa among women is 1%–3%, with rates in men believed to be one-tenth of those reported among women (1, 2). Studies conducted among military populations have found rates of bulimia nervosa of 8% for women and 7% for men, rates that exceed population estimates (3, 4). The elevated prevalence of eating disorders in military personnel is of concern because of significant associated comorbidities, including substance abuse (2, 5–8), mental health disorders (2, 5, 9), other physical complications (10, 11), and the potential for attempted suicide (12). Changes in eating resulting in weight gain or loss also have been associated with stress (13–15) and have been linked to physical and mental health problems (16, 17). Given the deleterious health consequences of eating disorders and weight changes to military personnel, it is important to identify factors that may explain increased risk for developing these problems.

Military personnel who deploy to combat regions are commonly exposed to trauma, such as witnessing serious injury or death (18–20). Research regarding past and current conflicts in the Persian Gulf has found that deployment-related stress produces anxiety, depression, post-traumatic stress disorder, and substance abuse among certain individuals (21–25). Therefore, we hypothesized that deployment in support of the wars in Iraq and Afghanistan would predict new-onset disordered eating and extreme weight change. Previous research has identified vulnerable subpopulations whose disordered eating may have been triggered by stressful events (9, 26–28). However, the majority of these studies used retrospective designs, which are vulnerable to recall bias. We investigated disordered eating levels before and after deployment to determine the prospective association between stressful life events and the development of eating disorders. Data for these analyses were from the Millennium Cohort Study, designed to evaluate the long-term effects of military service on health over a period of 21 years (29).

MATERIALS AND METHODS

Population and data sources

The population-based sample for the Millennium Cohort was randomly selected from all US military personnel on rosters as of October 2000. By use of a modified Dillman approach that involves minimizing costs and maximizing rewards for responding and that employs a series of reminders to elicit response commencing with a postcard (30), 77,047 of the 214,388 (36%) contacted personnel consented and enrolled in the first panel of the Millennium Cohort Study. This study protocol was approved by the institutional review board of the Naval Health Research Center, and the research was conducted in compliance with all applicable federal regulations governing the protection of human subjects in research (protocol NHRC.2000.007).

Of the 77,047 participants who completed a baseline survey between July 2001 and June 2003, 55,021 (71%) completed a follow-up survey from July 2004 to February 2006 and were included in this study. Of these individuals, 5,342 (9.7%) were excluded who deployed in support of the wars in Iraq and Afghanistan prior to the baseline assessment or who took their survey while deployed, since reporting during deployment would likely differ from reporting following deployment. Additionally, 724 (1.3%) individuals were excluded who did not answer any disordered-eating questions, and 577 (1.0%) were missing demographic or covariate data, leaving a population of 48,378 (87.9%). Of this population, 2,159 (4.5%) individuals met the criteria for disordered eating at baseline, so new-onset disordered eating analyses were performed using 46,219 participants. For the weight-change analyses, an additional 719 people with discrepant heights, 2,039 pregnant women, and 3,446 individuals who did not report either height or weight were excluded from the original analysis population, leaving 42,174 (76.7%).

Demographic and military data were obtained from the electronic personnel files of the Defense Manpower Data Center and included sex, birth date, race/ethnicity, education, marital status, branch of service, service component, military pay grade, military occupation, deployment experience to southwest Asia, Bosnia, or Kosovo between 1998 and 2000, deployment experience in support of the wars in Iraq and Afghanistan from 2001 to 2006, and length of the latter deployment.

Deployed individuals were defined as having completed at least 1 deployment in support of the wars in Iraq and Afghanistan between baseline and follow-up. Exposures reported at follow-up were used to assess combat experiences and were based on affirmative responses to questions that asked whether participants had personally witnessed death due to war, disaster, or tragic event; witnessed instances of physical abuse; and seen dead or decomposing bodies, maimed soldiers or civilians, or prisoners of war or refugees. Individuals reporting these experiences were designated as deployed with combat exposures, while those who did not were classified as deployed without combat exposures.

Baseline characteristics were included in these analyses to investigate whether certain subpopulations were more vulnerable to developing disordered eating or weight changes postdeployment. History of life stress, which included such items as divorce or having a family member die, was assessed by applying scoring mechanisms from the Holmes and Rahe Social Readjustment Rating Scale (31, 32) and then categorized as low/mild, moderate, or severe. History of a diagnosed mental disorder was determined by the reporting of a physician's diagnosis of depression, schizophrenia or psychosis, manic-depressive disorder, or post-traumatic stress disorder or by the reporting of medication use for anxiety, depression, or stress. Baseline survey questions identified nonsmokers, past smokers, or current smokers. History of alcohol misuse was evaluated by using the CAGE questionnaire (Cutting down, Annoyance by criticism, Guilty feeling, and Eye-openers) (33, 34), which has a test-retest reliability of 0.80–0.95 and an average sensitivity and specificity of 0.71 and 0.90, respectively (33). Finally, self-report at baseline of being on a special diet to lose weight was also examined.

Outcomes

Disordered eating was determined by using 8 survey questions from the Patient Health Questionnaire (35), and a survey-based diagnosis was made by use of criteria from the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (1). Although the survey was able to identify individuals with bulimia nervosa, subclinical bulimia nervosa, binge-eating disorder, and subclinical binge-eating disorder, they are reported in the aggregate as “disordered eating.” Bulimia nervosa was defined as endorsement of binge eating by indicating a loss of control over eating and consuming unusually large amounts of food as often as twice a week for the last 3 months, endorsement of at least 1 compensatory behavior such as vomiting or fasting as often as twice a week, answering “bothered a little” or “bothered a lot” by their weight or how they look, and being at least normal weight (body mass index, ≥18.5). Subclinical bulimia nervosa was defined the same as bulimia nervosa but with binge episodes and compensatory behaviors at subthreshold frequencies. Binge-eating disorder was defined as endorsement of binge eating as often as twice a week for the last 3 months with the absence of inappropriate compensatory behaviors. Subclinical binge-eating disorder was defined the same as binge-eating disorder but with binge episodes at subthreshold frequencies. New-onset disordered eating was defined as individuals who did not meet the criteria for disordered eating at baseline but met the criteria at follow-up.

Weight change from baseline to follow-up was determined by using self-reported height and weight from the questionnaire and creating a multilevel variable based on percent change in weight: extreme weight loss (≥10% loss), moderate weight loss (>3% but <10%), stable weight (remained within 3%), moderate weight gain (>3% but <10%), and extreme weight gain (≥10% gain). Cutpoints were determined by examining percent change in weight in the population, with a 10% change approximating 1 standard deviation from the mean. Women giving birth between baseline and follow-up surveys and participants whose height was more than 2 inches (5.08 cm) discrepant from baseline to follow-up were removed from these analyses.

Statistical analyses

Univariate analyses were completed to investigate unadjusted associations of disordered eating and weight changes with demographic, military, and behavioral risk factors. A model analysis was completed by using a variance inflation factor of 4 or greater to indicate the presence of multicollinearity among the independent variables. Multivariable logistic regression was used to compare the adjusted odds of association between deployment and new-onset disordered eating. Additional multivariable models estimated the adjusted odds of new-onset bulimia nervosa, subclinical bulimia nervosa, binge-eating disorder, and subclinical binge-eating disorder. Polychotomous logistic regression was used to compare the adjusted odds of association between deployment and weight change, with stable weight as the outcome reference group. For both disordered eating and weight change investigations, it was decided a priori to let nondeployed personnel be the reference group. Additional models were executed post hoc by using only deployed individuals to compare adjusted odds among those deployed with reported combat exposures with those deployed without reported combat exposures.

The saturated models for disordered eating and weight change contained all of the variables shown in Table 1. For the disordered-eating models, several first-order multiplicative interactions between combat deployment status and the following variables were investigated on the basis of a priori hypotheses: sex, age, service branch, history of life stress, history of diagnosed mental disorder, history of alcohol misuse, and self-report of being on a special diet for weight loss. For the weight-change models, the interaction between deployment status and age was tested. Interaction terms were considered significant at P ≤ 0.10. Because disordered eating and weight changes occur differently in men and women, the study population was stratified by sex. All other interactions examined did not yield significant P values, indicating no need for further stratification of the population. Confounders were variables that changed the measure of association more than 10% when removed from the model (36). Variables that were not confounders and not significant in the model using P < 0.05 were removed by a manual, backward, stepwise elimination method to create final models.

Table 1.

Baseline Characteristics of Women and Men by New-Onset Disordered Eating Status (N = 46,219), the Millennium Cohort Study, 2001–2006

Characteristic Women Men 
Total (n = 12,641) New-Onset Disordered Eating (n = 415) No Disordered Eating (n = 12,226) Total (n = 33,578) New-Onset Disordered Eating (n = 886) No Disordered Eating (n = 32,692) 
No. %a No. %a No. %a No. %a 
Deployment status           
    Nondeployed 10,686 349 84.1 10,337 84.5 24,830 666 75.2 24,164 73.9 
    Deployed without combat exposures 1,085 29 7.0 1,056 8.6 4,351 99 11.2 4,252 13.0 
    Deployed with combat exposures 870 37 8.9 833 6.8 4,397 121 13.7 4,276 13.1 
Experienced ≥1 deployments of >9 months           
    No 12,261 399 96.1 11,862 97.0 32,037 836 94.4 31,201 95.4 
    Yes 380 16 3.9 364 3.0 1,541 50 5.6 1,491 4.6 
Birth year           
    Before 1960 2,813 92 22.2 2,721 22.3 9,037 198* 22.3* 8,839* 27.0* 
    1960–1969 4,586 129 31.1 4,457 36.5 14,182 364* 41.1* 13,818* 42.3* 
    1970–1979 4,323 158 38.1 4,165 34.1 9,434 294* 33.2* 9,140* 28.0* 
    1980 or later 919 36 8.7 883 7.2 925 30* 3.4* 895* 2.7* 
Race/ethnicity           
    White, non-Hispanic 8,041 284 68.4 7,757 63.4 24,784 668* 75.4* 24,116* 73.8* 
    Black, non-Hispanic 2,529 70 16.9 2,459 20.1 3,147 61* 6.9* 3,086* 9.4* 
    Other 2,071 61 14.7 2,010 16.4 5,647 157* 17.7* 5,490* 16.8* 
Educationb           
    High school or less 5,465 182 43.9 5,283 43.2 14,372 453* 51.1* 13,919* 42.6* 
    Some college 3,284 111 26.7 3,173 26.0 8,933 199* 22.5* 8,734* 26.7* 
    College degree 2,427 75 18.1 2,352 19.2 6,433 158* 17.8* 6,275* 19.2* 
    Graduate school 1,465 47 11.3 1,418 11.6 3,840 76* 8.6* 3,764* 11.5* 
Marital statusb           
    Married 6,329 194 46.7 6,135 50.2 24,548 616* 69.5* 23,932* 73.2* 
    Never married 4,668 152 36.6 4,516 36.9 7,317 226* 25.5* 7,091* 21.7* 
    Divorced, widowed, separated 1,644 69 16.6 1,575 12.9 1,713 44* 5.0* 1,669* 5.1* 
Service branchb           
    Army 6,347 211 50.8 6,136 50.2 15,536 447* 50.5* 15,089* 46.2* 
    Air Force 3,772 120 28.9 3,652 29.9 10,198 206* 23.3* 9,992* 30.6* 
    Navy/Coast Guard 2,257 71 17.1 2,186 17.9 6,128 182* 20.5* 5,946* 18.2* 
    Marine Corps 265 13 3.1 252 2.1 1,716 51* 5.8* 1,665* 5.1* 
Service componentb           
    Active duty 6,315 224 54.0 6,091 49.8 18,971 548* 61.9* 18,423* 56.4* 
    Reserve/National Guard 6,326 191 46.0 6,135 50.2 14,607 338* 38.1* 14,269* 43.6* 
Military pay gradeb           
    Officer 3,445 103 24.8 3,342 27.3 9,353 206* 23.3* 9,147* 28.0* 
    Enlisted 9,196 312 75.2 8,884 72.7 24,225 680* 76.7* 23,545* 72.0* 
Occupational codesb           
    Combat specialists 794 26 6.3 768 6.3 8,440 223 25.2 8,217 25.1 
    Electronic equipment repair 734 31 7.5 703 5.8 3,472 91 10.3 3,381 10.3 
    Communications/intelligence 854 29 7.0 825 6.7 2,376 64 7.2 2,312 7.1 
    Health care 3,003 95 22.9 2,908 23.8 2,422 69 7.8 2,353 7.2 
    Other technical and allied specialists 265 10 2.4 255 2.1 896 28 3.2 868 2.7 
    Functional support and administration 4,417 125 30.1 4,292 35.1 5,273 122 13.8 5,151 15.8 
    Electrical/mechanical equipment repair 620 21 5.1 599 4.9 5,507 144 16.3 5,363 16.4 
    Craft workers 189 1.2 184 1.5 1,205 38 4.3 1,167 3.6 
    Service and supply 1,098 43 10.4 1,055 8.6 2,789 74 8.4 2,715 8.3 
    Students, trainees, and other 667 30 7.2 637 5.2 1,198 33 3.7 1,165 3.6 
Deployment prior to baselinec           
    None 10,257 350 84.3 9,907 81.0 18,939 471 53.2 18,468 56.5 
    1991 Gulf War only 806 25 6.0 781 6.4 2,891 92 10.4 2,799 8.6 
    Bosnia/Kosovo/southwest Asia only 1,472 38 9.2 1,434 11.7 9,636 275 31.0 9,361 28.6 
    Both 106 0.5 104 0.9 2,112 48 5.4 2,064 6.3 
History of life stressorsbd           
    Low/mild 9,175 272* 65.5* 8,903* 72.8* 30,029 758* 85.6* 29,271* 89.5* 
    Moderate 2,760 109* 26.3* 2,651* 21.7* 3,021 98* 11.1* 2,923* 8.9* 
    Major 706 34* 8.2* 672* 5.5* 528 30* 3.4* 498* 1.5* 
History of diagnosed mental disorderb           
    No 10,747 307* 74.0* 10,440* 85.4* 31,562 783* 88.4* 30,779* 94.1* 
    Yes 1,894 108* 26.0* 1,786* 14.6* 2,016 103* 11.6* 1,913* 5.9* 
Smoking statusb           
    Nonsmoker 7,977 244 58.8 7,733 63.3 19,671 490 55.3 19,181 58.7 
    Ever/past smoker 2,790 109 26.3 2,681 21.9 8,448 246 27.8 8,202 25.1 
    Current smoker 1,874 62 14.9 1,812 14.8 5,459 150 16.9 5,309 16.2 
History of alcohol misusebe           
    No 11,084 342* 82.4* 10,742* 87.9* 26,925 634* 71.6* 26,291* 80.4* 
    Yes 1,557 73* 17.6* 1,484* 12.1* 6,653 252* 28.4* 6,401* 19.6* 
Special diet for weight lossbf           
    No 9,937 257* 61.9* 9,680* 79.2* 30,189 689* 77.8* 29 500* 90.2* 
    Yes 2,704 158* 38.1* 2,546* 20.8* 3,389 197* 22.2* 3,192* 9.8* 
Characteristic Women Men 
Total (n = 12,641) New-Onset Disordered Eating (n = 415) No Disordered Eating (n = 12,226) Total (n = 33,578) New-Onset Disordered Eating (n = 886) No Disordered Eating (n = 32,692) 
No. %a No. %a No. %a No. %a 
Deployment status           
    Nondeployed 10,686 349 84.1 10,337 84.5 24,830 666 75.2 24,164 73.9 
    Deployed without combat exposures 1,085 29 7.0 1,056 8.6 4,351 99 11.2 4,252 13.0 
    Deployed with combat exposures 870 37 8.9 833 6.8 4,397 121 13.7 4,276 13.1 
Experienced ≥1 deployments of >9 months           
    No 12,261 399 96.1 11,862 97.0 32,037 836 94.4 31,201 95.4 
    Yes 380 16 3.9 364 3.0 1,541 50 5.6 1,491 4.6 
Birth year           
    Before 1960 2,813 92 22.2 2,721 22.3 9,037 198* 22.3* 8,839* 27.0* 
    1960–1969 4,586 129 31.1 4,457 36.5 14,182 364* 41.1* 13,818* 42.3* 
    1970–1979 4,323 158 38.1 4,165 34.1 9,434 294* 33.2* 9,140* 28.0* 
    1980 or later 919 36 8.7 883 7.2 925 30* 3.4* 895* 2.7* 
Race/ethnicity           
    White, non-Hispanic 8,041 284 68.4 7,757 63.4 24,784 668* 75.4* 24,116* 73.8* 
    Black, non-Hispanic 2,529 70 16.9 2,459 20.1 3,147 61* 6.9* 3,086* 9.4* 
    Other 2,071 61 14.7 2,010 16.4 5,647 157* 17.7* 5,490* 16.8* 
Educationb           
    High school or less 5,465 182 43.9 5,283 43.2 14,372 453* 51.1* 13,919* 42.6* 
    Some college 3,284 111 26.7 3,173 26.0 8,933 199* 22.5* 8,734* 26.7* 
    College degree 2,427 75 18.1 2,352 19.2 6,433 158* 17.8* 6,275* 19.2* 
    Graduate school 1,465 47 11.3 1,418 11.6 3,840 76* 8.6* 3,764* 11.5* 
Marital statusb           
    Married 6,329 194 46.7 6,135 50.2 24,548 616* 69.5* 23,932* 73.2* 
    Never married 4,668 152 36.6 4,516 36.9 7,317 226* 25.5* 7,091* 21.7* 
    Divorced, widowed, separated 1,644 69 16.6 1,575 12.9 1,713 44* 5.0* 1,669* 5.1* 
Service branchb           
    Army 6,347 211 50.8 6,136 50.2 15,536 447* 50.5* 15,089* 46.2* 
    Air Force 3,772 120 28.9 3,652 29.9 10,198 206* 23.3* 9,992* 30.6* 
    Navy/Coast Guard 2,257 71 17.1 2,186 17.9 6,128 182* 20.5* 5,946* 18.2* 
    Marine Corps 265 13 3.1 252 2.1 1,716 51* 5.8* 1,665* 5.1* 
Service componentb           
    Active duty 6,315 224 54.0 6,091 49.8 18,971 548* 61.9* 18,423* 56.4* 
    Reserve/National Guard 6,326 191 46.0 6,135 50.2 14,607 338* 38.1* 14,269* 43.6* 
Military pay gradeb           
    Officer 3,445 103 24.8 3,342 27.3 9,353 206* 23.3* 9,147* 28.0* 
    Enlisted 9,196 312 75.2 8,884 72.7 24,225 680* 76.7* 23,545* 72.0* 
Occupational codesb           
    Combat specialists 794 26 6.3 768 6.3 8,440 223 25.2 8,217 25.1 
    Electronic equipment repair 734 31 7.5 703 5.8 3,472 91 10.3 3,381 10.3 
    Communications/intelligence 854 29 7.0 825 6.7 2,376 64 7.2 2,312 7.1 
    Health care 3,003 95 22.9 2,908 23.8 2,422 69 7.8 2,353 7.2 
    Other technical and allied specialists 265 10 2.4 255 2.1 896 28 3.2 868 2.7 
    Functional support and administration 4,417 125 30.1 4,292 35.1 5,273 122 13.8 5,151 15.8 
    Electrical/mechanical equipment repair 620 21 5.1 599 4.9 5,507 144 16.3 5,363 16.4 
    Craft workers 189 1.2 184 1.5 1,205 38 4.3 1,167 3.6 
    Service and supply 1,098 43 10.4 1,055 8.6 2,789 74 8.4 2,715 8.3 
    Students, trainees, and other 667 30 7.2 637 5.2 1,198 33 3.7 1,165 3.6 
Deployment prior to baselinec           
    None 10,257 350 84.3 9,907 81.0 18,939 471 53.2 18,468 56.5 
    1991 Gulf War only 806 25 6.0 781 6.4 2,891 92 10.4 2,799 8.6 
    Bosnia/Kosovo/southwest Asia only 1,472 38 9.2 1,434 11.7 9,636 275 31.0 9,361 28.6 
    Both 106 0.5 104 0.9 2,112 48 5.4 2,064 6.3 
History of life stressorsbd           
    Low/mild 9,175 272* 65.5* 8,903* 72.8* 30,029 758* 85.6* 29,271* 89.5* 
    Moderate 2,760 109* 26.3* 2,651* 21.7* 3,021 98* 11.1* 2,923* 8.9* 
    Major 706 34* 8.2* 672* 5.5* 528 30* 3.4* 498* 1.5* 
History of diagnosed mental disorderb           
    No 10,747 307* 74.0* 10,440* 85.4* 31,562 783* 88.4* 30,779* 94.1* 
    Yes 1,894 108* 26.0* 1,786* 14.6* 2,016 103* 11.6* 1,913* 5.9* 
Smoking statusb           
    Nonsmoker 7,977 244 58.8 7,733 63.3 19,671 490 55.3 19,181 58.7 
    Ever/past smoker 2,790 109 26.3 2,681 21.9 8,448 246 27.8 8,202 25.1 
    Current smoker 1,874 62 14.9 1,812 14.8 5,459 150 16.9 5,309 16.2 
History of alcohol misusebe           
    No 11,084 342* 82.4* 10,742* 87.9* 26,925 634* 71.6* 26,291* 80.4* 
    Yes 1,557 73* 17.6* 1,484* 12.1* 6,653 252* 28.4* 6,401* 19.6* 
Special diet for weight lossbf           
    No 9,937 257* 61.9* 9,680* 79.2* 30,189 689* 77.8* 29 500* 90.2* 
    Yes 2,704 158* 38.1* 2,546* 20.8* 3,389 197* 22.2* 3,192* 9.8* 
*

P < 0.05 (significantly associated with new-onset disordered eating by using chi-squared tests).

a

Percentages may not sum to 100 because of rounding.

b

Characteristic reported at baseline assessment.

c

Deployment prior to baseline refers to deployment to conflicts before the current deployments in support of the wars in Iraq and Afghanistan. Deployment to Bosnia, Kosovo, or southwest Asia includes any deployment to these contingencies between 1998 and 2000.

d

The Social Readjustment Rating Scale (32).

e

Alcohol misuse is defined as at least 1 positive response to the CAGE questions (i.e., Cutting down, Annoyance by criticism, Guilty feeling, and Eye-openers) (33, 34).

f

Positive response to whether the subject used “special diet programs for weight loss.”

Additional analyses were conducted among deployed persons only to isolate the effect of combat exposure on the odds of disordered eating and weight change. Data management and statistical analyses were performed by using SAS, version 9.1.3, statistical software (SAS Institute, Inc., Cary, North Carolina).

RESULTS

The cumulative incidence of self-reported disordered eating over 2.7 years, the average time between baseline and follow-up, was 3.3% for women and 2.6% for men. Among women, disordered eating was identified in 5.5% at baseline and 5.2% at follow-up, with 63% of the follow-up cases identified as newly reported. Among men, disordered eating was identified in 4.0% at baseline and 3.9% at follow-up, with 67% of the cases identified as newly reported. The subgroups with a higher proportion of women and men with new-onset disordered eating were those deployed with combat exposures, born in 1980 or later, of white, non-Hispanic race, in the Marine Corps, on active duty, and enlisted personnel or those who reported a history of a past major life stress, a diagnosed mental disorder, misuse of alcohol, or on a special diet for weight loss (Table 1).

Multivariable logistic regression revealed that deployment was not significantly related to new-onset disordered eating in women or men, after adjustment (Table 2). Military pay grade, occupation, deployment to other conflicts prior to baseline, deployment experience longer than 9 months, and smoking status were removed from both models because they were not significant, nor were they confounders. Covariates significantly associated with new-onset disordered eating among women and men were history of a diagnosed mental disorder and self-report of being on a special diet for weight loss. When examining the adjusted multivariable models for the individual eating disorders, we found no significant associations between deployment and new-onset bulimia nervosa, subclinical bulimia nervosa, binge-eating disorder, or subclinical binge-eating disorder (data not shown).

Table 2.

Odds of New-Onset Disordered Eating Adjusted for the Baseline Demographic, Behavioral, and Occupational Characteristics of Participants (N = 46,219), the Millennium Cohort Study, 2001–2006

Characteristic Women (n = 12,641) Men (n = 33,578) 
Odds Ratioa 95% Confidence Interval Odds Ratioa 95% Confidence Interval 
Deployment status—deployers only     
    Deployed without combat exposures 1.00  1.00  
    Deployed with combat exposures 1.78b 1.02, 3.11 1.13 0.83, 1.54 
Deployment status—entire study population     
    Nondeployed 1.00  1.00  
    Deployed without combat exposures 0.83 0.56, 1.23 0.91 0.73, 1.13 
    Deployed with combat exposures 1.29 0.91, 1.85 0.94 0.77, 1.15 
Birth year     
    Before 1960 1.00  1.00  
    1960–1969 0.91 0.69, 1.21 1.09 0.91, 1.32 
    1970–1979 1.26 0.92, 1.73 1.19 0.96, 1.49 
    1980 or later 1.54 0.96, 2.47 1.16 0.74, 1.80 
Race/ethnicity     
    White, non-Hispanic 1.00  1.00  
    Black, non-Hispanic 0.82 0.62, 1.08 0.67b 0.52, 0.88 
    Other 0.81 0.60, 1.09 0.98 0.81, 1.19 
Educationc     
    High school or less 1.00  1.00  
    Some college 1.11 0.84, 1.48 0.85 0.69, 1.04 
    College degree 1.08 0.80, 1.46 0.87 0.72, 1.06 
    Graduate school 1.20 0.82, 1.75 0.73b 0.56, 0.96 
Marital statusc     
    Married 1.00  1.00  
    Never married 1.00 0.78, 1.27 1.10 0.92, 1.33 
    Divorced, widowed, separated 1.34 1.00, 1.79 1.00 0.73, 1.37 
Service branchc     
    Army 1.00  1.00  
    Air Force 0.87 0.66, 1.14 0.79b 0.64, 0.96 
    Navy/Coast Guard 0.93 0.73, 1.24 0.95 0.79, 1.15 
    Marine Corps 1.31 0.70, 2.37 0.91 0.67, 1.22 
Service componentc     
    Reserve/National Guard 1.00  1.00  
    Active duty 1.19 0.95, 1.48 1.28b 1.10, 1.49 
History of life stressorscd     
    Low/mild 1.00  1.00  
    Moderate 1.12 0.89, 1.43 1.15 0.92, 1.44 
    Major 1.24 0.84, 1.82 1.75b 1.18, 2.57 
History of diagnosed mental disorderc     
    No 1.00  1.00  
    Yes 1.83b 1.45, 2.32 1.88b 1.51, 2.34 
History of alcohol misusece     
    No 1.00  1.00  
    Yes 1.29 0.99, 1.68 1.44b 1.24, 1.67 
Special diet for weight losscf     
    No 1.00  1.00  
    Yes 2.26b 1.84, 2.78 2.54b 2.15, 2.99 
Characteristic Women (n = 12,641) Men (n = 33,578) 
Odds Ratioa 95% Confidence Interval Odds Ratioa 95% Confidence Interval 
Deployment status—deployers only     
    Deployed without combat exposures 1.00  1.00  
    Deployed with combat exposures 1.78b 1.02, 3.11 1.13 0.83, 1.54 
Deployment status—entire study population     
    Nondeployed 1.00  1.00  
    Deployed without combat exposures 0.83 0.56, 1.23 0.91 0.73, 1.13 
    Deployed with combat exposures 1.29 0.91, 1.85 0.94 0.77, 1.15 
Birth year     
    Before 1960 1.00  1.00  
    1960–1969 0.91 0.69, 1.21 1.09 0.91, 1.32 
    1970–1979 1.26 0.92, 1.73 1.19 0.96, 1.49 
    1980 or later 1.54 0.96, 2.47 1.16 0.74, 1.80 
Race/ethnicity     
    White, non-Hispanic 1.00  1.00  
    Black, non-Hispanic 0.82 0.62, 1.08 0.67b 0.52, 0.88 
    Other 0.81 0.60, 1.09 0.98 0.81, 1.19 
Educationc     
    High school or less 1.00  1.00  
    Some college 1.11 0.84, 1.48 0.85 0.69, 1.04 
    College degree 1.08 0.80, 1.46 0.87 0.72, 1.06 
    Graduate school 1.20 0.82, 1.75 0.73b 0.56, 0.96 
Marital statusc     
    Married 1.00  1.00  
    Never married 1.00 0.78, 1.27 1.10 0.92, 1.33 
    Divorced, widowed, separated 1.34 1.00, 1.79 1.00 0.73, 1.37 
Service branchc     
    Army 1.00  1.00  
    Air Force 0.87 0.66, 1.14 0.79b 0.64, 0.96 
    Navy/Coast Guard 0.93 0.73, 1.24 0.95 0.79, 1.15 
    Marine Corps 1.31 0.70, 2.37 0.91 0.67, 1.22 
Service componentc     
    Reserve/National Guard 1.00  1.00  
    Active duty 1.19 0.95, 1.48 1.28b 1.10, 1.49 
History of life stressorscd     
    Low/mild 1.00  1.00  
    Moderate 1.12 0.89, 1.43 1.15 0.92, 1.44 
    Major 1.24 0.84, 1.82 1.75b 1.18, 2.57 
History of diagnosed mental disorderc     
    No 1.00  1.00  
    Yes 1.83b 1.45, 2.32 1.88b 1.51, 2.34 
History of alcohol misusece     
    No 1.00  1.00  
    Yes 1.29 0.99, 1.68 1.44b 1.24, 1.67 
Special diet for weight losscf     
    No 1.00  1.00  
    Yes 2.26b 1.84, 2.78 2.54b 2.15, 2.99 
a

Odds ratios and associated 95% confidence intervals are adjusted for all the other variables in the table.

b

Adjusted odds of new-onset disordered eating are significant as shown by associated confidence intervals using logistic regression.

c

The model was adjusted for this characteristic at baseline.

d

The Social Readjustment Rating Scale (32).

e

Alcohol misuse is defined as at least 1 positive response to the CAGE questions (i.e., Cutting down, Annoyance by criticism, Guilty feeling, and Eye-openers) (33, 34).

f

Positive response to whether the subject used “special diet programs for weight loss.”

Analyses focusing on the deployed population revealed that women deployed with combat exposures were 1.78 times more likely to develop new-onset disordered eating (95% confidence interval (CI): 1.02, 3.11) (Table 2) and 2.35 times more likely to lose an extreme amount of weight (95% CI: 1.17, 4.70) (Table 3) compared with women deployed without combat exposures. These models were adjusted for the same covariates when modeling the entire population, and these associations were not found among men.

Table 3.

Adjusted Odds of Weight Changea Among Millennium Cohort Study Women From Baseline (July 2001–June 2003) to Follow-up (July 2004–January 2006) (N = 10,186)

Characteristic Extreme Weight Loss (n = 272) Moderate Weight Loss (n = 1,260) Moderate Weight Gain (n = 3,373) Extreme Weight Gain (n = 1,902) 
Odds Ratio 95% Confidence Interval Odds Ratio 95% Confidence Interval Odds Ratio 95% Confidence Interval Odds Ratio 95% Confidence Interval 
Deployment status—deployers only         
    Deployed without combat exposures 1.00  1.00  1.00  1.00  
    Deployed with combat exposures 2.35b 1.17, 4.70 1.28 0.91, 1.80 1.05 0.81, 1.37 1.11 0.80, 1.53 
Deployment status—entire study population         
    Nondeployed 1.00  1.00  1.00  1.00  
    Deployed without combat exposures 0.75 0.44, 1.30 1.05 0.82, 1.34 1.00 0.84, 1.20 0.89 0.71, 1.11 
    Deployed with combat exposures 1.59 0.99, 2.53 1.33b 1.03, 1.73 1.06 0.87, 1.30 1.00 0.78, 1.29 
Experienced ≥1 deployments of ≥9 months         
    No 1.00  1.00  1.00  1.00  
    Yes 0.73 0.33, 1.60 0.91 0.61, 1.35 1.23 0.92, 1.66 0.76 0.52, 1.13 
Birth year         
    Before 1960 1.00  1.00  1.00  1.00  
    1960–1969 0.84 0.60, 1.18 1.11 0.94, 1.32 1.09 0.96, 1.23 1.14 0.97, 1.33 
    1970–1979 1.23 0.84, 1.81 1.21 0.98, 1.49 1.03 0.89, 1.20 1.26b 1.05, 1.51 
    1980 or later 1.97b 1.07, 3.61 1.44b 1.03, 2.03 1.07 0.82, 1.39 1.82b 1.37, 2.43 
Race/ethnicity         
    White, non-Hispanic 1.00  1.00  1.00  1.00  
    Black, non-Hispanic 1.04 0.74, 1.46 1.04 0.87, 1.25 1.01 0.88, 1.15 0.96 0.82, 1.13 
    Other 0.90 0.61, 1.32 1.03 0.86, 1.25 0.97 0.84, 1.11 0.91 0.76, 1.08 
Educationc         
    High school or less 1.00  1.00  1.00  1.00  
    Some college 0.80 0.57, 1.15 0.90 0.74, 1.09 0.99 0.86, 1.13 0.83b 0.71, 0.98 
    College degree 0.70 0.45, 1.10 1.05 0.84, 1.31 0.85 0.72, 1.01 0.84 0.69, 1.03 
    Graduate school 0.66 0.36, 1.22 0.83 0.62, 1.12 0.76b 0.61, 0.94 0.79 0.59, 1.05 
Marital statusc         
    Married 1.00  1.00  1.00  1.00  
    Never married 0.62b 0.45, 0.85 0.95 0.82, 1.11 0.98 0.87, 1.10 1.11 0.97, 1.28 
    Divorced, widowed, separated 0.87 0.59, 1.26 0.91 0.74, 1.12 1.15 0.99, 1.33 1.15 0.97, 1.38 
Service branchc         
    Army 1.00  1.00  1.00  1.00  
    Air Force 0.81 0.57, 1.14 0.90 0.76, 1.07 1.08 0.95, 1.23 1.13 0.97, 1.32 
    Navy/Coast Guard 1.11 0.79, 1.56 1.00 0.83, 1.20 1.07 0.93, 1.23 1.17 1.00, 1.38 
    Marine Corpsd   0.68 0.41, 1.13 0.91 0.65, 1.29 0.95 0.64, 1.41 
Service componentc         
    Reserve/National Guard 1.00  1.00  1.00  1.00  
    Active duty 0.81 0.62, 1.07 0.88 0.77, 1.02 1.01 0.91, 1.12 1.11 0.98, 1.26 
Military pay gradec         
    Officer 1.00  1.00  1.00  1.00  
    Enlisted 1.23 0.80, 1.90 1.04 0.84, 1.29 1.15 0.98, 1.35 2.09b 1.70, 2.58 
History of life stressorsc,e         
    Low/mild 1.00  1.00  1.00  1.00  
    Moderate 1.32 0.99, 1.78 1.06 0.90, 1.25 1.14b 1.01, 1.29 1.31b 1.13, 1.51 
    Major 1.37 0.85, 2.20 0.96 0.72, 1.29 1.16 0.94, 1.44 1.54b 1.22, 1.95 
History of diagnosed mental disorderc         
    No 1.00  1.00  1.00  1.00  
    Yes 1.21 0.87, 1.68 1.25b 1.04, 1.50 1.08 0.94, 1.24 1.56b 1.35, 1.83 
Smoking statusc         
    Nonsmoker 1.00  1.00  1.00  1.00  
    Ever/past smoker 1.43b 1.05, 1.94 1.39b 1.18, 1.64 1.08 0.96, 1.23 1.17b 1.01, 1.35 
    Current smoker 1.58b 1.12, 2.22 1.27b 1.05, 1.54 0.96 0.83, 1.12 1.10 0.93, 1.30 
History of alcohol misusec,f         
    No 1.00  1.00  1.00  1.00  
    Yes 1.32 0.95, 1.84 1.09 0.90, 1.32 0.98 0.85, 1.13 0.82b 0.69, 0.97 
Special diet for weight lossc,g         
    No 1.00  1.00  1.00  1.00  
    Yes 2.05b 1.56, 2.68 1.18 1.00, 1.38 1.32b 1.17, 1.48 1.99b 1.74, 2.27 
Characteristic Extreme Weight Loss (n = 272) Moderate Weight Loss (n = 1,260) Moderate Weight Gain (n = 3,373) Extreme Weight Gain (n = 1,902) 
Odds Ratio 95% Confidence Interval Odds Ratio 95% Confidence Interval Odds Ratio 95% Confidence Interval Odds Ratio 95% Confidence Interval 
Deployment status—deployers only         
    Deployed without combat exposures 1.00  1.00  1.00  1.00  
    Deployed with combat exposures 2.35b 1.17, 4.70 1.28 0.91, 1.80 1.05 0.81, 1.37 1.11 0.80, 1.53 
Deployment status—entire study population         
    Nondeployed 1.00  1.00  1.00  1.00  
    Deployed without combat exposures 0.75 0.44, 1.30 1.05 0.82, 1.34 1.00 0.84, 1.20 0.89 0.71, 1.11 
    Deployed with combat exposures 1.59 0.99, 2.53 1.33b 1.03, 1.73 1.06 0.87, 1.30 1.00 0.78, 1.29 
Experienced ≥1 deployments of ≥9 months         
    No 1.00  1.00  1.00  1.00  
    Yes 0.73 0.33, 1.60 0.91 0.61, 1.35 1.23 0.92, 1.66 0.76 0.52, 1.13 
Birth year         
    Before 1960 1.00  1.00  1.00  1.00  
    1960–1969 0.84 0.60, 1.18 1.11 0.94, 1.32 1.09 0.96, 1.23 1.14 0.97, 1.33 
    1970–1979 1.23 0.84, 1.81 1.21 0.98, 1.49 1.03 0.89, 1.20 1.26b 1.05, 1.51 
    1980 or later 1.97b 1.07, 3.61 1.44b 1.03, 2.03 1.07 0.82, 1.39 1.82b 1.37, 2.43 
Race/ethnicity         
    White, non-Hispanic 1.00  1.00  1.00  1.00  
    Black, non-Hispanic 1.04 0.74, 1.46 1.04 0.87, 1.25 1.01 0.88, 1.15 0.96 0.82, 1.13 
    Other 0.90 0.61, 1.32 1.03 0.86, 1.25 0.97 0.84, 1.11 0.91 0.76, 1.08 
Educationc         
    High school or less 1.00  1.00  1.00  1.00  
    Some college 0.80 0.57, 1.15 0.90 0.74, 1.09 0.99 0.86, 1.13 0.83b 0.71, 0.98 
    College degree 0.70 0.45, 1.10 1.05 0.84, 1.31 0.85 0.72, 1.01 0.84 0.69, 1.03 
    Graduate school 0.66 0.36, 1.22 0.83 0.62, 1.12 0.76b 0.61, 0.94 0.79 0.59, 1.05 
Marital statusc         
    Married 1.00  1.00  1.00  1.00  
    Never married 0.62b 0.45, 0.85 0.95 0.82, 1.11 0.98 0.87, 1.10 1.11 0.97, 1.28 
    Divorced, widowed, separated 0.87 0.59, 1.26 0.91 0.74, 1.12 1.15 0.99, 1.33 1.15 0.97, 1.38 
Service branchc         
    Army 1.00  1.00  1.00  1.00  
    Air Force 0.81 0.57, 1.14 0.90 0.76, 1.07 1.08 0.95, 1.23 1.13 0.97, 1.32 
    Navy/Coast Guard 1.11 0.79, 1.56 1.00 0.83, 1.20 1.07 0.93, 1.23 1.17 1.00, 1.38 
    Marine Corpsd   0.68 0.41, 1.13 0.91 0.65, 1.29 0.95 0.64, 1.41 
Service componentc         
    Reserve/National Guard 1.00  1.00  1.00  1.00  
    Active duty 0.81 0.62, 1.07 0.88 0.77, 1.02 1.01 0.91, 1.12 1.11 0.98, 1.26 
Military pay gradec         
    Officer 1.00  1.00  1.00  1.00  
    Enlisted 1.23 0.80, 1.90 1.04 0.84, 1.29 1.15 0.98, 1.35 2.09b 1.70, 2.58 
History of life stressorsc,e         
    Low/mild 1.00  1.00  1.00  1.00  
    Moderate 1.32 0.99, 1.78 1.06 0.90, 1.25 1.14b 1.01, 1.29 1.31b 1.13, 1.51 
    Major 1.37 0.85, 2.20 0.96 0.72, 1.29 1.16 0.94, 1.44 1.54b 1.22, 1.95 
History of diagnosed mental disorderc         
    No 1.00  1.00  1.00  1.00  
    Yes 1.21 0.87, 1.68 1.25b 1.04, 1.50 1.08 0.94, 1.24 1.56b 1.35, 1.83 
Smoking statusc         
    Nonsmoker 1.00  1.00  1.00  1.00  
    Ever/past smoker 1.43b 1.05, 1.94 1.39b 1.18, 1.64 1.08 0.96, 1.23 1.17b 1.01, 1.35 
    Current smoker 1.58b 1.12, 2.22 1.27b 1.05, 1.54 0.96 0.83, 1.12 1.10 0.93, 1.30 
History of alcohol misusec,f         
    No 1.00  1.00  1.00  1.00  
    Yes 1.32 0.95, 1.84 1.09 0.90, 1.32 0.98 0.85, 1.13 0.82b 0.69, 0.97 
Special diet for weight lossc,g         
    No 1.00  1.00  1.00  1.00  
    Yes 2.05b 1.56, 2.68 1.18 1.00, 1.38 1.32b 1.17, 1.48 1.99b 1.74, 2.27 
a

Weight change was determined by using percent change calculated as the self-reported weight in pounds at follow-up minus the self-reported weight in pounds at baseline assessment, divided by baseline weight. Weight-change categories were defined as follows: extreme weight loss (≥10% loss), moderate weight loss (>3% but <10% loss), stable weight (remained within 3%), moderate weight gain (>3% but <10% gain), and extreme weight gain (≥10% gain). Stable weight (n = 3,379) was the reference category for the polychotomous logistic regression model.

b

Adjusted odds of new-onset disordered eating are significant as shown by associated confidence intervals using polychotomous logistic regression.

c

The model was adjusted for this characteristic at baseline.

d

Small cell sizes prohibited the calculation of an odds ratio and corresponding confidence interval among Marine Corps women in the extreme weight loss group.

e

The Social Readjustment Rating Scale (32).

f

Alcohol misuse is defined as at least 1 positive response to the CAGE questions (i.e., Cutting down, Annoyance by criticism, Guilty feeling, and Eye-openers) (33, 34).

g

Positive response to whether the subject used “special diet programs for weight loss.”

The average weight gain in men and women between baseline and follow-up was 4.7 pounds (2.1 kg) and 5.9 pounds (2.7 kg), respectively, which represented a 2.6% increase among men and a 4.1% increase among women (data not shown). Approximately 33% of women and 48% of men reported stable weight between baseline and follow-up, regardless of deployment status (Table 4). Among women deployed with combat exposures, a greater proportion lost an extreme or moderate amount of weight compared with women deployed without combat exposures and with nondeployed women. Among men deployed with combat exposures, a greater proportion gained a moderate or extreme amount of weight compared with men deployed without combat exposures and with nondeployed men.

Table 4.

Proportion of Women and Men in Each Weight Change Categorya by Deployment Status (N = 42,174), the Millennium Cohort Study, 2001–2006

 Extreme Weight Loss Moderate Weight Loss Stable Weight Moderate Weight Gain Extreme Weight Gain 
 No. No. No. No. No. 
Women (n = 10,186)           
    Nondeployed 228 2.7 1,035 12.1 2,851 33.4 2,808 32.9 1,620 19.0 
    Deployed without combat exposures 16 1.9 108 12.5 288 33.3 301 34.8 152 17.6 
    Deployed with combat exposures 28 3.6 117 15.0 240 30.8 264 33.9 130 16.7 
Men (n = 31 988)           
    Nondeployed 373 1.6 2,590 10.9 11,247 47.4 7,242 30.5 2,269 9.6 
    Deployed without combat exposures 55 1.4 415 10.2 1,993 49.1 1,248 30.8 347 8.6 
    Deployed with combat exposures 54 1.3 447 10.6 1,926 45.8 1,348 32.0 434 10.3 
 Extreme Weight Loss Moderate Weight Loss Stable Weight Moderate Weight Gain Extreme Weight Gain 
 No. No. No. No. No. 
Women (n = 10,186)           
    Nondeployed 228 2.7 1,035 12.1 2,851 33.4 2,808 32.9 1,620 19.0 
    Deployed without combat exposures 16 1.9 108 12.5 288 33.3 301 34.8 152 17.6 
    Deployed with combat exposures 28 3.6 117 15.0 240 30.8 264 33.9 130 16.7 
Men (n = 31 988)           
    Nondeployed 373 1.6 2,590 10.9 11,247 47.4 7,242 30.5 2,269 9.6 
    Deployed without combat exposures 55 1.4 415 10.2 1,993 49.1 1,248 30.8 347 8.6 
    Deployed with combat exposures 54 1.3 447 10.6 1,926 45.8 1,348 32.0 434 10.3 
a

Weight change was determined by using percent change calculated as the self-reported weight in pounds at follow-up minus the self-reported weight in pounds at baseline assessment, divided by baseline weight. Weight-change categories were defined as follows: extreme weight loss (≥10% loss), moderate weight loss (>3% but <10% loss), stable weight (remained within 3%), moderate weight gain (>3% but <10% gain), and extreme weight gain (≥10% gain).

The adjusted odds of weight change from baseline to follow-up were explored by using polychotomous logistic regression models for women and men. Occupation and previous deployment experience were removed from the models because they were not statistically significant, nor were they confounders. After adjustment, women deployed with combat exposures were 1.33 times more likely to lose a moderate amount of weight between baseline and follow-up, compared with nondeployed women (95% CI: 1.03, 1.73) (Table 3). Women deployed with combat exposures were 2.35 times more likely to lose an extreme amount compared with women who deployed without combat exposures (95% CI: 1.17, 4.70) (Table 3).

After adjustment, men deployed without combat exposures were significantly less likely to lose a moderate amount of weight (odds ratio = 0.88, 95% CI: 0.78, 0.99) or to gain an extreme amount of weight (odds ratio = 0.82, 95% CI: 0.72, 0.93) compared with nondeployed men (Table 5).

Table 5.

Adjusted Odds of Weight Changea Among Millennium Cohort Study Men From Baseline (July 2001–June 2003) to Follow-up (July 2004–January 2006) (N = 31,988)

Characteristic Extreme Weight Lossa (n = 482) Moderate Weight Lossa (n = 3,452) Moderate Weight Gaina (n = 9,838) Extreme Weight Gaina (n = 3,050) 
Odds Ratio 95% Confidence Interval Odds Ratio 95% Confidence Interval Odds Ratio 95% Confidence Interval Odds Ratio 95% Confidence Interval 
Deployment status—deployers only         
    Deployed without combat exposures 1.00  1.00  1.00  1.00  
    Deployed with combat exposures 0.95 0.62, 1.46 1.17 0.99, 1.38 1.04 0.93, 1.17 1.18 0.98, 1.41 
Deployment status—entire study population         
    Nondeployed 1.00  1.00  1.00  1.00  
    Deployed without combat exposures 0.89 0.66, 1.20 0.88b 0.78, 0.99 0.94 0.87, 1.02 0.82b 0.72, 0.93 
    Deployed with combat exposures 0.88 0.64, 1.22 0.97 0.86, 1.10 0.98 0.90, 1.07 0.92 0.81, 1.05 
Experienced ≥1 deployments of ≥9 months         
    No 1.00  1.00  1.00  1.00  
    Yes 0.94 0.55, 1.61 1.14 0.93, 1.39 1.13 0.98, 1.29 1.07 0.87, 1.32 
Birth year         
    Before 1960 1.00  1.00  1.00  1.00  
    1960–1969 0.95 0.76, 1.20 1.01 0.92, 1.12 1.07 1.00, 1.15 1.02 0.91, 1.15 
    1970–1979 1.05 0.78, 1.41 1.16b 1.03, 1.31 1.27b 1.17, 1.39 1.63b 1.42, 1.85 
    1980 and later 1.76 0.96, 3.22 1.36b 1.02, 1.80 1.54b 1.26, 1.87 4.22b 3.37, 5.30 
Race/ethnicity         
    White, non-Hispanic 1.00  1.00  1.00  1.00  
    Black, non-Hispanic 0.79 0.55, 1.12 0.98 0.86, 1.12 0.97 0.89, 1.07 0.99 0.86, 1.13 
    Other 0.59b 0.43, 0.81 0.93 0.83, 1.04 1.05 0.98, 1.13 0.96 0.85, 1.08 
Educationc         
    High school or less 1.00  1.00  1.00  1.00  
    Some college 0.99 0.76, 1.29 0.85b 0.76, 0.94 0.95 0.88, 1.02 0.93 0.83, 1.05 
    College degree 0.93 0.65, 1.31 0.84b 0.73, 0.97 0.82b 0.74, 0.91 0.64b 0.54, 0.76 
    Graduate school 1.00 0.63, 1.56 0.87 0.73, 1.05 0.80b 0.70, 0.91 0.68b 0.53, 0.86 
Marital statusc         
    Married 1.00  1.00  1.00  1.00  
    Never married 1.12 0.86, 1.45 1.11 1.00, 1.24 1.12b 1.05, 1.21 1.36b 1.22, 1.52 
    Divorced, widowed, separated 1.12 0.74, 1.67 1.06 0.89, 1.26 1.24b 1.10, 1.39 1.11 0.92, 1.34 
Service branchc         
    Army 1.00  1.00  1.00  1.00  
    Air Force 0.87 0.67, 1.13 1.17b 1.06, 1.31 0.98 0.91, 1.05 0.99 0.88, 1.12 
    Navy/Coast Guard 1.16 0.91, 1.49 1.14b 1.03, 1.27 0.96 0.89, 1.03 0.96 0.86, 1.09 
    Marine Corps 0.80 0.49, 1.30 0.86 0.71, 1.04 1.01 0.89, 1.14 1.15 0.97, 1.37 
Service componentc         
    Reserve/National Guard 1.00  1.00  1.00  1.00  
    Active duty 0.89 0.72, 1.09 0.96 0.88, 1.04 1.10b 1.04, 1.17 1.21b 1.10, 1.32 
Military pay gradec         
    Officer 1.00  1.00  1.00  1.00  
    Enlisted 1.12 0.80, 1.55 0.99 0.86, 1.13 1.28b 1.17, 1.41 1.81b 1.52, 2.15 
History of life stressorscd         
    Low/mild 1.00  1.00  1.00  1.00  
    Moderate 1.13 0.84, 1.52 1.00 0.88, 1.14 1.11b 1.02, 1.22 1.30b 1.14, 1.48 
    Major 1.28 0.72, 2.29 1.24 0.95, 1.62 0.92 0.75, 1.14 1.29 0.97, 1.71 
History of diagnosed mental disorderc         
    No 1.00  1.00  1.00  1.00  
    Yes 1.83b 1.34, 2.49 1.54b 1.33, 1.79 1.40b 1.25, 1.56 1.84b 1.59, 2.13 
Smoking statusc         
    Nonsmoker 1.00  1.00  1.00  1.00  
    Ever/past smoker 1.41b 1.13, 1.75 1.11b 1.02, 1.22 0.95 0.89, 1.01 1.05 0.95, 1.16 
    Current smoker 1.57b 1.22, 2.02 1.22b 1.09, 1.35 0.97 0.90, 1.05 1.21b 1.09, 1.35 
History of alcohol misusece         
    No 1.00  1.00  1.00  1.00  
    Yes 1.38b 1.12, 1.69 1.06 0.97, 1.16 0.95 0.89, 1.01 1.04 0.94, 1.14 
Special diet for weight losscf         
    No 1.00  1.00  1.00  1.00  
    Yes 1.42b 1.07, 1.86 1.20b 1.06, 1.36 1.41b 1.30, 1.53 2.04b 1.82, 2.29 
Characteristic Extreme Weight Lossa (n = 482) Moderate Weight Lossa (n = 3,452) Moderate Weight Gaina (n = 9,838) Extreme Weight Gaina (n = 3,050) 
Odds Ratio 95% Confidence Interval Odds Ratio 95% Confidence Interval Odds Ratio 95% Confidence Interval Odds Ratio 95% Confidence Interval 
Deployment status—deployers only         
    Deployed without combat exposures 1.00  1.00  1.00  1.00  
    Deployed with combat exposures 0.95 0.62, 1.46 1.17 0.99, 1.38 1.04 0.93, 1.17 1.18 0.98, 1.41 
Deployment status—entire study population         
    Nondeployed 1.00  1.00  1.00  1.00  
    Deployed without combat exposures 0.89 0.66, 1.20 0.88b 0.78, 0.99 0.94 0.87, 1.02 0.82b 0.72, 0.93 
    Deployed with combat exposures 0.88 0.64, 1.22 0.97 0.86, 1.10 0.98 0.90, 1.07 0.92 0.81, 1.05 
Experienced ≥1 deployments of ≥9 months         
    No 1.00  1.00  1.00  1.00  
    Yes 0.94 0.55, 1.61 1.14 0.93, 1.39 1.13 0.98, 1.29 1.07 0.87, 1.32 
Birth year         
    Before 1960 1.00  1.00  1.00  1.00  
    1960–1969 0.95 0.76, 1.20 1.01 0.92, 1.12 1.07 1.00, 1.15 1.02 0.91, 1.15 
    1970–1979 1.05 0.78, 1.41 1.16b 1.03, 1.31 1.27b 1.17, 1.39 1.63b 1.42, 1.85 
    1980 and later 1.76 0.96, 3.22 1.36b 1.02, 1.80 1.54b 1.26, 1.87 4.22b 3.37, 5.30 
Race/ethnicity         
    White, non-Hispanic 1.00  1.00  1.00  1.00  
    Black, non-Hispanic 0.79 0.55, 1.12 0.98 0.86, 1.12 0.97 0.89, 1.07 0.99 0.86, 1.13 
    Other 0.59b 0.43, 0.81 0.93 0.83, 1.04 1.05 0.98, 1.13 0.96 0.85, 1.08 
Educationc         
    High school or less 1.00  1.00  1.00  1.00  
    Some college 0.99 0.76, 1.29 0.85b 0.76, 0.94 0.95 0.88, 1.02 0.93 0.83, 1.05 
    College degree 0.93 0.65, 1.31 0.84b 0.73, 0.97 0.82b 0.74, 0.91 0.64b 0.54, 0.76 
    Graduate school 1.00 0.63, 1.56 0.87 0.73, 1.05 0.80b 0.70, 0.91 0.68b 0.53, 0.86 
Marital statusc         
    Married 1.00  1.00  1.00  1.00  
    Never married 1.12 0.86, 1.45 1.11 1.00, 1.24 1.12b 1.05, 1.21 1.36b 1.22, 1.52 
    Divorced, widowed, separated 1.12 0.74, 1.67 1.06 0.89, 1.26 1.24b 1.10, 1.39 1.11 0.92, 1.34 
Service branchc         
    Army 1.00  1.00  1.00  1.00  
    Air Force 0.87 0.67, 1.13 1.17b 1.06, 1.31 0.98 0.91, 1.05 0.99 0.88, 1.12 
    Navy/Coast Guard 1.16 0.91, 1.49 1.14b 1.03, 1.27 0.96 0.89, 1.03 0.96 0.86, 1.09 
    Marine Corps 0.80 0.49, 1.30 0.86 0.71, 1.04 1.01 0.89, 1.14 1.15 0.97, 1.37 
Service componentc         
    Reserve/National Guard 1.00  1.00  1.00  1.00  
    Active duty 0.89 0.72, 1.09 0.96 0.88, 1.04 1.10b 1.04, 1.17 1.21b 1.10, 1.32 
Military pay gradec         
    Officer 1.00  1.00  1.00  1.00  
    Enlisted 1.12 0.80, 1.55 0.99 0.86, 1.13 1.28b 1.17, 1.41 1.81b 1.52, 2.15 
History of life stressorscd         
    Low/mild 1.00  1.00  1.00  1.00  
    Moderate 1.13 0.84, 1.52 1.00 0.88, 1.14 1.11b 1.02, 1.22 1.30b 1.14, 1.48 
    Major 1.28 0.72, 2.29 1.24 0.95, 1.62 0.92 0.75, 1.14 1.29 0.97, 1.71 
History of diagnosed mental disorderc         
    No 1.00  1.00  1.00  1.00  
    Yes 1.83b 1.34, 2.49 1.54b 1.33, 1.79 1.40b 1.25, 1.56 1.84b 1.59, 2.13 
Smoking statusc         
    Nonsmoker 1.00  1.00  1.00  1.00  
    Ever/past smoker 1.41b 1.13, 1.75 1.11b 1.02, 1.22 0.95 0.89, 1.01 1.05 0.95, 1.16 
    Current smoker 1.57b 1.22, 2.02 1.22b 1.09, 1.35 0.97 0.90, 1.05 1.21b 1.09, 1.35 
History of alcohol misusece         
    No 1.00  1.00  1.00  1.00  
    Yes 1.38b 1.12, 1.69 1.06 0.97, 1.16 0.95 0.89, 1.01 1.04 0.94, 1.14 
Special diet for weight losscf         
    No 1.00  1.00  1.00  1.00  
    Yes 1.42b 1.07, 1.86 1.20b 1.06, 1.36 1.41b 1.30, 1.53 2.04b 1.82, 2.29 
a

Weight change was determined by using percent change calculated as the self-reported weight in pounds at follow-up minus the self-reported weight in pounds at baseline assessment, divided by baseline weight. Weight-change categories were defined as follows: extreme weight loss (≥10% loss), moderate weight loss (>3% but <10% loss), stable weight (remained within 3%), moderate weight gain (>3% but <10% gain), and extreme weight gain (≥10% gain). Stable weight (n = 15,166) was the reference category for the polychotomous logistic regression model.

b

Adjusted odds of new-onset disordered eating are significant as shown by associated confidence intervals using polychotomous logistic regression.

c

The model was adjusted for this characteristic at baseline.

d

The Social Readjustment Rating Scale (32).

e

Alcohol misuse is defined as at least 1 positive response to the CAGE questions (i.e., Cutting down, Annoyance by criticism, Guilty feeling, and Eye-openers) (33, 34).

f

Positive response to whether the subject used “special diet programs for weight loss.”

DISCUSSION

Prospective data on the associations between documented stressful and traumatic life events and the development of disordered eating are lacking. This is the first study to prospectively document the impact of deployment on disordered eating or weight change in a large population-based military cohort. No statistically significant overall effect of deployment on increased risk of disordered eating in men and women in comparison with nondeployed personnel was found. However, deployment with combat exposures was associated with a significantly increased risk of new-onset disordered eating and extreme weight loss compared with deployment without combat exposures in women.

These findings suggest that disordered eating and extreme weight change that arise following deployment may be due to the trauma experienced during combat rather than due to deployment itself. The adverse effects of combat trauma have been documented in other investigations of post-traumatic stress disorder (25) and alcohol use (37) before and after deployment. The military selectively deploys its most healthy and fit force, so individuals that do not deploy may be less healthy than those that deploy. Our results support this, since the lowest rates of disordered eating in both men and women were among those who deployed and did not experience combat, and the highest rates were among those who deployed and reported combat exposures. We also found similar cumulative incidence rates of disordered eating over the time span between baseline and follow-up for men and women. Although the rates in women are typically much higher than those in the men in the general population (1), other studies conducted on active duty military populations have reported similar rates between men and women (3, 4). Expected compliance with military weight standards may be an explanation for the high rates in this male population due to concerns over job loss or career advancement.

Although it has been documented that stress increases food consumption and encourages unhealthy food choices (15), this study did not find a robust association between deployment and weight gain. It has been suggested that, contrary to the early days of the war when food was limited to ready-to-eat packaged meals, individuals recently deployed have access to large quantities and varieties of food, making weight gain more probable (38). Alternatively, deployed personnel may be more active than their nondeployed counterparts, because deployed personnel are not maintaining families and household activities; they may have more time to devote to fitness activities. Despite the average weight gain observed over an average of 2.7 years, an association was found between deployment with combat exposures and moderate weight loss among women. No notable association between deployment status and weight change was found among men, suggesting that the trauma of deployment with combat exposure may have a greater impact on weight change in women.

We also examined weight change by whether participants had separated from military service. Although the proportion of individuals in most weight-change categories was relatively equal regardless of separation status, we did find that a larger proportion of separated individuals gained an extreme amount of weight. Future follow-up studies of this Millennium Cohort will yield insight into whether separation from military service plays a role in weight change.

We found that men and women who reported being on a diet for weight loss were significantly more likely to experience disordered eating and weight changes. This may be related to the fact that the military maintains weight standards for service members (39, 40), and studies have shown that pressure to meet these standards places personnel at risk for disordered eating and body-image concerns (41, 42).

There are limitations to this study that should be noted. Designed oversampling of women, those previously deployed, and Reserve/National Guard personnel may limit how representative the Millennium Cohort is of the military or those who deploy. However, investigations of possible biases in the Millennium Cohort baseline sample suggest a representative sample of US military personnel, measured by demographic and health characteristics, and reliable health and exposure reporting (29, 43–50). Personnel that did not respond to the follow-up survey were more likely to be younger, black non-Hispanic or unknown race/ethnicity, Marines, and current smokers and to report post-traumatic stress disorder and depression symptoms or diagnosis at baseline (37), potentially providing a less representative sample at follow-up. In addition, it was not feasible to adjust for deployment location in this study because of the large number of individuals with multiple deployments to various locations, although individuals deployed to different regions may have experienced different frequencies of disordered eating or weight changes.

Another important study limitation was that the sensitive definition of combat exposures was not specific to deployment and did not include items such as receiving small arms fire or being responsible for the death of an enemy combatant. Nonetheless, reporting of experiences, such as witnessing trauma or death due to war, has been shown to be associated with adverse mental health outcomes in previous investigations using the Millennium Cohort and in other studies (22, 25, 37). In addition, the term new onset must be interpreted with caution, because disordered eating may be episodic in nature, and we were not able to capture information on disordered eating prior to baseline. Another limitation was the inability to assess purging disorders in this population because of skip rules within the survey that allowed respondents to skip questions concerning the use of inappropriate compensatory behaviors (such as vomiting or overexercising) if they denied binge-eating episodes. These disorders are potentially as severe as and common as bulimia nervosa or binge-eating disorder (51), which would have provided more power to this investigation had we been able to examine them. Additionally, because of the large sample size, it was not feasible to complete structured clinical interviews or objective assessments of height and weight at both assessments. However, similar survey-based diagnoses of disordered eating have demonstrated good concurrent validity with interview-based diagnoses (52, 53), and studies have agreed that self-reported height and weight are reliable and valid for large epidemiologic studies (54, 55). Nonetheless, assessment methods were held constant across time. Thus, limitations of self-reported data should not affect evaluation of changes over time in the development of new-onset disordered eating.

Despite these limitations, this study has strengths. Limited work on the prevalence of disordered eating in US military populations has been conducted. This study is the first to prospectively investigate the association between military deployment and disordered-eating behaviors and weight change in a large population-based cohort of women and men. Robust investigations of these associations were allowed by the high participation rates at follow-up, the large sample of both men and women, and demographic, occupational, and behavioral variables to adjust for possible confounding. Finally, the current study makes a significant contribution to the literature by demonstrating a prospective association between the trauma of combat exposure and the development of disordered eating in women.

In conclusion, deployment in support of the wars in Iraq and Afghanistan was not associated with new-onset disordered eating or weight change among military personnel. However, findings suggest that the trauma of combat exposure may have greater effects on eating and weight differences in women than men, since significant associations between deployment with combat exposures and disordered eating and weight loss were revealed among women only. In addition, this population, on average, gained weight over the study period. This may reflect trends similar to those in the general population, rather than an association with deployment. As this Millennium Cohort ages, it will become important that future weight change studies adjust for comorbid psychological disorders and distinguish characteristics of those in military service versus those who have transitioned to civilian life. In addition to being the first large-scale epidemiologic study to quantify the association between deployment to war and disordered eating and weight changes, this study highlights the need for continued research in the areas of dieting and weight change among military personnel related to occupational weight standards.

Abbreviation

    Abbreviation
  • CI

    confidence interval

Author affiliations: Department of Defense Center for Deployment Health Research, Naval Health Research Center, San Diego, California (Isabel G. Jacobson, Tyler C. Smith, Besa Smith, Margaret A. K. Ryan); Department of Psychology, Florida State University, Tallahassee, Florida (Pamela K. Keel); Madigan Army Medical Center, Fort Lewis, Washington (Paul J. Amoroso); Air Force Research Laboratory, Wright-Patterson Air Force Base, Ohio (Timothy S. Wells); US Army Research Institute of Environmental Medicine, Natick, Massachusetts (Gaston P. Bathalon); and Seattle Epidemiologic Research and Information Center, Department of Veterans Affairs Puget Sound Health Care System, Seattle, Washington (Edward J. Boyko).

The Millennium Cohort Study is funded through the Military Operational Medicine Research Program of the US Army Medical Research and Materiel Command, Fort Dietrick, Maryland.

The authors thank Scott L. Seggerman and Greg D. Boyd from the Management Information Division, Defense Manpower Data Center, Seaside, California. They also thank Michelle Stoia from the Naval Health Research Center and the professionals from the US Army Medical Research and Materiel Command, especially those from the Military Operational Medicine Research Program, Fort Detrick, Maryland. They appreciate the support of the Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, Maryland. Additionally, the authors thank the following members of the Millennium Cohort Study Team: Gina Creaven, James Davies, Lacy Farnell, Gia Gumbs, Cynthia LeardMann, Travis Leleu, Jamie McGrew, Robert Reed, Katherine Snell, Steven Spiegel, Kari Welch, James Whitmer, and Charlene Wong from the Department of Defense Center for Deployment Health Research, Naval Health Research Center, San Diego, California.

This represents report 08-03, supported by the Department of Defense, under work unit no. 60002.

The views expressed in this article are those of the authors and do not reflect the official policy or position of the Department of the Navy, Department of the Army, Department of the Air Force, Department of Defense, or the US government. The funding organization (Military Operational Medicine Research Program) had no role in the design and conduct of the study; collection, analysis, or preparation of data; or preparation, review, or approval of the manuscript.

Conflict of interest: none declared.

References

1.
American Psychiatric Association
Diagnostic and Statistical Manual of Mental Disorders
 , 
2000
4th ed, text revision
Washington, DC
American Psychiatric Association
2.
Carlat
DJ
Camargo
CA
Herzog
DB
Eating disorders in males: a report on 135 patients
Am J Psychiatry
 , 
1997
, vol. 
154
 
8
(pg. 
1127
-
1132
)
3.
McNulty
PA
Prevalence and contributing factors of eating disorder behaviors in active duty service women in the Army, Navy, Air Force, and Marines
Mil Med
 , 
2001
, vol. 
166
 
1
(pg. 
53
-
58
)
4.
McNulty
PA
Prevalence and contributing factors of eating disorder behaviors in active duty Navy men
Mil Med
 , 
1997
, vol. 
162
 
11
(pg. 
753
-
758
)
5.
Keel
PK
Klump
KL
Miller
KB
, et al.  . 
Shared transmission of eating disorders and anxiety disorders
Int J Eat Disord
 , 
2005
, vol. 
38
 
2
(pg. 
99
-
105
)
6.
Herzog
DB
Franko
DL
Dorer
DJ
, et al.  . 
Drug abuse in women with eating disorders
Int J Eat Disord
 , 
2006
, vol. 
39
 
5
(pg. 
364
-
368
)
7.
Franko
DL
Dorer
DJ
Keel
PK
, et al.  . 
How do eating disorders and alcohol use disorder influence each other?
Int J Eat Disord
 , 
2005
, vol. 
38
 
3
(pg. 
200
-
207
)
8.
Keel
PK
Mitchell
JE
Miller
KB
, et al.  . 
Long-term outcome of bulimia nervosa
Arch Gen Psychiatry
 , 
1999
, vol. 
56
 
1
(pg. 
63
-
69
)
9.
Brewerton
TD
Eating disorders, trauma, and comorbidity: focus on PTSD
Eat Disord
 , 
2007
, vol. 
15
 
4
(pg. 
285
-
304
)
10.
Miller
KK
Grinspoon
SK
Ciampa
J
, et al.  . 
Medical findings in outpatients with anorexia nervosa
Arch Intern Med
 , 
2005
, vol. 
165
 
5
(pg. 
561
-
566
)
11.
Hadley
SJ
Walsh
BT
Gastrointestinal disturbances in anorexia nervosa and bulimia nervosa
Curr Drug Targets CNS Neurol Disord
 , 
2003
, vol. 
2
 
1
(pg. 
1
-
9
)
12.
Franko
DL
Keel
PK
Suicidality in eating disorders: occurrence, correlates, and clinical implications
Clin Psychol Rev
 , 
2006
, vol. 
26
 
6
(pg. 
769
-
782
)
13.
Drapeau
V
Therrien
F
Richard
D
, et al.  . 
Is visceral obesity a physiological adaptation to stress?
Panminerva Med
 , 
2003
, vol. 
45
 
3
(pg. 
189
-
195
)
14.
Adam
TC
Epel
ES
Stress, eating and the reward system
Physiol Behav
 , 
2007
, vol. 
91
 
4
(pg. 
449
-
458
)
15.
Zellner
DA
Loaiza
S
Gonzalez
Z
, et al.  . 
Food selection changes under stress
Physiol Behav
 , 
2006
, vol. 
87
 
4
(pg. 
789
-
793
)
16.
Hasler
G
Lissek
S
Ajdacic
V
, et al.  . 
Major depression predicts an increase in long-term body weight variability in young adults
Obes Res.
 , 
2005
, vol. 
13
 
11
(pg. 
1991
-
1998
)
17.
Friedman
MA
Schwartz
MB
Brownell
KD
Differential relation of psychological functioning with the history and experience of weight cycling
J Consult Clin Psychol
 , 
1998
, vol. 
66
 
4
(pg. 
646
-
650
)
18.
Benotsch
EG
Brailey
K
Vasterling
JJ
, et al.  . 
War zone stress, personal and environmental resources, and PTSD symptoms in Gulf War veterans: a longitudinal perspective
J Abnorm Psychol
 , 
2000
, vol. 
109
 
2
(pg. 
205
-
213
)
19.
Carson
MA
Paulus
LA
Lasko
NB
, et al.  . 
Psychophysiologic assessment of posttraumatic stress disorder in Vietnam nurse veterans who witnessed injury or death
J Consult Clin Psychol
 , 
2000
, vol. 
68
 
5
(pg. 
890
-
897
)
20.
Hobfoll
SE
Spielberger
CD
Breznitz
S
, et al.  . 
War-related stress. Addressing the stress of war and other traumatic events
Am Psychol
 , 
1991
, vol. 
46
 
8
(pg. 
848
-
855
)
21.
Hoge
CW
Auchterlonie
JL
Milliken
CS
Mental health problems, use of mental health services, and attrition from military service after returning from deployment to Iraq or Afghanistan
JAMA
 , 
2006
, vol. 
295
 
9
(pg. 
1023
-
1032
)
22.
Hoge
CW
Castro
CA
Messer
SC
, et al.  . 
Combat duty in Iraq and Afghanistan, mental health problems, and barriers to care
N Engl J Med
 , 
2004
, vol. 
351
 
1
(pg. 
13
-
22
)
23.
Fiedler
N
Ozakinci
G
Hallman
W
, et al.  . 
Military deployment to the Gulf War as a risk factor for psychiatric illness among US troops
Br J Psychiatry
 , 
2006
, vol. 
188
 (pg. 
453
-
459
)
24.
Black
DW
Carney
CP
Peloso
PM
, et al.  . 
Gulf War veterans with anxiety: prevalence, comorbidity, and risk factors
Epidemiology
 , 
2004
, vol. 
15
 
2
(pg. 
135
-
142
)
25.
Smith
TC
Ryan
MA
Wingard
DL
, et al.  . 
New onset and persistent symptoms of post-traumatic stress disorder self reported after deployment and combat exposures: prospective population based US military cohort study
BMJ
 , 
2008
, vol. 
336
 
7640
(pg. 
366
-
371
)
26.
Fryer
S
Waller
G
Kroese
BS
Stress, coping, and disturbed eating attitudes in teenage girls
Int J Eat Disord
 , 
1997
, vol. 
22
 
4
(pg. 
427
-
436
)
27.
Sassaroli
S
Mezzaluna
C
Amurri
A
, et al.  . 
Stress plays a role in the association between cognitive constructs and measures of eating disorders in male subjects
Eat Weight Disord
 , 
2005
, vol. 
10
 
2
(pg. 
117
-
124
)
28.
Sassaroli
S
Ruggiero
GM
The role of stress in the association between low self-esteem, perfectionism, and worry, and eating disorders
Int J Eat Disord
 , 
2005
, vol. 
37
 
2
(pg. 
135
-
141
)
29.
Ryan
MA
Smith
TC
Smith
B
, et al.  . 
Millennium Cohort: enrollment begins a 21-year contribution to understanding the impact of military service
J Clin Epidemiol
 , 
2007
, vol. 
60
 
2
(pg. 
181
-
191
)
30.
Dillman
DA
Mail and Telephone Surveys: The Total Design Method
 , 
1978
New York, NY
Wiley
 
xvi, 325
31.
Hobson
CJ
Kamen
J
Szostek
J
, et al.  . 
Stressful life events: a revision and update of the Social Readjustment Rating Scale
Int J Stress Manag
 , 
1998
, vol. 
5
 
1
(pg. 
1
-
23
)
32.
Holmes
TH
Rahe
RH
The Social Readjustment Rating Scale
J Psychosom Res
 , 
1967
, vol. 
11
 
2
(pg. 
213
-
218
)
33.
Dhalla
S
Kopec
JA
The CAGE questionnaire for alcohol misuse: a review of reliability and validity studies
Clin Invest Med
 , 
2007
, vol. 
30
 
1
(pg. 
33
-
41
)
34.
Ewing
JA
Detecting alcoholism. The CAGE questionnaire
JAMA
 , 
1984
, vol. 
252
 
14
(pg. 
1905
-
1907
)
35.
Spitzer
RL
Kroenke
K
Williams
JB
Validation and utility of a self-report version of PRIME-MD: the PHQ primary care study. Primary Care Evaluation of Mental Disorders. Patient Health Questionnaire
JAMA
 , 
1999
, vol. 
282
 
18
(pg. 
1737
-
1744
)
36.
Maldonado
G
Greenland
S
Simulation study of confounder-selection strategies
Am J Epidemiol
 , 
1993
, vol. 
138
 
11
(pg. 
923
-
936
)
37.
Jacobson
IG
Ryan
MA
Hooper
TI
, et al.  . 
Alcohol use and alcohol-related problems before and after military combat deployment
JAMA
 , 
2008
, vol. 
300
 
6
(pg. 
663
-
675
)
38.
Hennessy-Fiske
M
U.S. soldiers in Iraq face the battle of the bulge
The Seattle Times. July 10, 2007
 , 
2007
Seattle, WA
The Seattle Times Company
 
39.
Friedl
KE
Leu
JR
Body fat standards and individual physical readiness in a randomized Army sample: screening weights, methods of fat assessment, and linkage to physical fitness
Mil Med
 , 
2002
, vol. 
167
 
12
(pg. 
994
-
1000
)
40.
Graham
WF
Hourani
LL
Sorenson
D
, et al.  . 
Demographic differences in body composition of Navy and Marine Corps personnel: findings from the perception of wellness and readiness assessment
Mil Med
 , 
2000
, vol. 
165
 
1
(pg. 
60
-
69
)
41.
Peterson
AL
Talcott
GW
Kelleher
WJ
, et al.  . 
Bulimic weight-loss behaviors in military versus civilian weight-management programs
Mil Med
 , 
1995
, vol. 
160
 
12
(pg. 
616
-
620
)
42.
Lauder
TD
Williams
MV
Campbell
CS
, et al.  . 
Abnormal eating behaviors in military women
Med Sci Sports Exerc
 , 
1999
, vol. 
31
 
9
(pg. 
1265
-
1271
)
43.
Riddle
JR
Smith
TC
Smith
B
, et al.  . 
Millennium Cohort: the 2001–2003 baseline prevalence of mental disorders in the U.S. military
J Clin Epidemiol
 , 
2007
, vol. 
60
 
2
(pg. 
192
-
201
)
44.
Smith
B
Leard
CA
Smith
TC
, et al.  . 
Anthrax vaccination in the Millennium Cohort: validation and measures of health
Am J Prev Med
 , 
2007
, vol. 
32
 
4
(pg. 
347
-
353
)
45.
Smith
TC
Jacobson
IG
Smith
B
, et al.  . 
The occupational role of women in military service: validation of occupation and prevalence of exposures in the Millennium Cohort Study
Int J Environ Health Res
 , 
2007
, vol. 
17
 
4
(pg. 
271
-
284
)
46.
Smith
TC
Smith
B
Jacobson
IG
, et al.  . 
Reliability of standard health assessment instruments in a large, population-based cohort study
Ann Epidemiol
 , 
2007
, vol. 
17
 
7
(pg. 
525
-
532
)
47.
LeardMann
CA
Smith
B
Smith
TC
, et al.  . 
Smallpox vaccination: comparison of self-reported and electronic vaccine records in the Millennium Cohort Study
Hum Vaccin
 , 
2007
, vol. 
3
 
6
(pg. 
245
-
251
)
48.
Smith
B
Smith
TC
Gray
GC
, et al.  . 
When epidemiology meets the Internet: Web-based surveys in the Millennium Cohort Study
Am J Epidemiol
 , 
2007
, vol. 
166
 
11
(pg. 
1345
-
1354
)
49.
Smith
B
Wingard
DL
Ryan
MA
, et al.  . 
U.S. military deployment during 2001–2006: comparison of subjective and objective data sources in a large prospective health study
Ann Epidemiol
 , 
2007
, vol. 
17
 
12
(pg. 
976
-
982
)
50.
Wells
TS
Jacobson
IG
Smith
TC
, et al.  . 
Prior health care utilization as a potential determinant of enrollment in a 21-year prospective study, the Millennium Cohort Study
Eur J Epidemiol
 , 
2008
, vol. 
23
 
2
(pg. 
79
-
87
)
51.
Keel
PK
Purging disorder: subthreshold variant or full-threshold eating disorder?
Int J Eat Disord
 , 
2007
, vol. 
40
 
suppl
(pg. 
S89
-
S94
)
52.
Keel
PK
Crow
S
Davis
TL
, et al.  . 
Assessment of eating disorders: comparison of interview and questionnaire data from a long-term follow-up study of bulimia nervosa
J Psychosom Res
 , 
2002
, vol. 
53
 
5
(pg. 
1043
-
1047
)
53.
Black
CM
Wilson
GT
Assessment of eating disorders: interview versus questionnaire
Int J Eat Disord
 , 
1996
, vol. 
20
 
1
(pg. 
43
-
50
)
54.
Spencer
EA
Appleby
PN
Davey
GK
, et al.  . 
Validity of self-reported height and weight in 4808 EPIC-Oxford participants
Public Health Nutr
 , 
2002
, vol. 
5
 
4
(pg. 
561
-
565
)
55.
Stunkard
AJ
Albaum
JM
The accuracy of self-reported weights
Am J Clin Nutr
 , 
1981
, vol. 
34
 
8
(pg. 
1593
-
1599
)