OBJECTIVES:This cross-sectional investigation examined associations between clinically diagnosed insomnia (CDI) and comorbid conditions in United States military service members (SMs). METHODS:A stratified random sample of SMs completed an on-line questionnaire assessing their demographic and lifestyle characteristics. Diagnosed medical conditions for a six-month period prior to questionnaire completion were obtained from a comprehensive military electronic medical surveillance system and grouped into 18 general (largely systemic) and 30 specific clinically diagnosed medical categories (CDMCs). CDMC prevalence odds was compared among those with (n = 771) and without (n = 25,909) CDI. RESULTS:After adjustments for potentially confounding demographic and lifestyle characteristics, CDI was associated with higher odds of a diagnosis in 17 of the general CDMCs and 26 of the specific CDMCs. The five general CDMCs with the largest differences between those with and without CDI were mental/behavioral diseases (odds ratio [OR] = 7.68, 95% confidence interval [95%CI] = 6.54-9.01), signs/symptoms/abnormal labs (OR = 4.99, 95%CI = 4.19-5.93), diseases of the musculoskeletal system (OR = 4.43, 95%CI = 3.72-5.28), endocrine/nutritional/metabolic diseases (OR = 2.97, 95%CI = 2.47-3.58), and diseases of the digestive system (OR = 2.68, 95%CI = 2.18-3.28). The five specific CDMCs with the highest adjusted odds among those with and without CDI were sleep-related movement disorder (OR = 14.68, 95%CI = 9.26-23.26), fibromyalgia (OR = 14.14, 95%CI = 5.74-34.80), post-traumatic stress disorder (OR = 12.94, 95%CI = 10.09-16.59), anxiety (OR = 9.40, 95%CI = 7.71-11.46), and traumatic brain injury (OR = 8.52, 95%CI = 5.93-12.24). Prevalence of CDI increased as the number of CDMCs increased: SMs with 0-1, 2-3, 4-5 and ≥6 general CDMCs had CDI prevalences of 0.5%, 3.2%, 6.7%, and 10.9%, respectively. CONCLUSION:In a young, physically active population CDI was associated with many CDMCs involving multiple physiological systems.

This cross-sectional investigation examined associations between body mass index (BMI) and filled prescription medications (FPMs) among military service members (SMs). A stratified random sample of active duty SMs was obtained from military workforce records. Participants (n = 26,117) completed a questionnaire on demographics and lifestyle factors and their FPMs were obtained from the military Pharmacy Data Transaction Service. Medications were classified by their American Hospital Formulary System Pharmacologic-Therapeutic Classification System (PTCS) codes. FPMs across PTCS codes were compared across three BMI levels: normal weight (<25.0 kg/m2), overweight (25.0-29.9 kg/m2), and obese (≥30 kg/m2). SMs who were overweight and obese had 1.21 (95 %confidence interval [95 %CI]=1.14-1.29) and 1.60 (95 %CI=1.47-1.75) times higher odds of a FPM than normal weight SMs, respectively. Compared to normal weight SMs, SMs who were overweight had higher prevalence of FPMs in 14 of 20 PTCS codes and SMs who were obese in 15 of 20 PTCS codes, after adjustment for demographic and lifestyle factors. In most PTCS codes there was a dose-response such that as BMI level increased so did the prevalence of FPMs. In this young, physically active group of SMs, prevalence of many types of FPMs increased as BMI increased in a dose-response pattern.

PURPOSE:Military personnel may be repeatedly exposed to high-noise environments that may increase tinnitus risk. Previous military research on tinnitus has often utilized small samples of personnel with specific experiences and exposures (e.g., combat deployment), with few examinations leveraging longitudinal data. The purpose of this study was to determine the incidence and associated risk factors for new-onset tinnitus in a large prospective and representative military cohort. METHOD:This study utilized data from the Millennium Cohort Study, the largest and longest running longitudinal health study of service members and veterans, to ascertain self-reported and medical diagnoses of tinnitus. Multivariable logistic regression was employed to identify factors associated with new-onset tinnitus. RESULTS:New-onset tinnitus was self-reported by 10.7% (n = 2,527) of participants while 3.5% (n = 511) had a medical record tinnitus diagnosis. Tinnitus risk was associated with multiple characteristics, including active duty service, being a member of the Army or Marine Corps, combat deployment experience, combat specialist occupation, prior history of mild traumatic brain injury, panic/anxiety, posttraumatic stress disorder (PTSD) alone, and PTSD comorbid with depression. CONCLUSIONS:This may be the first study to determine new-onset tinnitus utilizing both self-reported and medical record data in a large prospective cohort of service members and veterans. Additional prospective studies are needed to corroborate our findings and further describe the temporal relationships of military occupational and mental health characteristics with service-related new-onset tinnitus.

BackgroundThe effects of blast overpressure (BOP) on brain health are increasingly recognized, yet longitudinal research into these effects after separation from military service remains limited. This study assessed the association between high-level blast (HLB) and low-level blast (LLB) exposure during military service using data from the Millennium Cohort Study (MCS) and diagnoses related to traumatic brain injury (TBI) diagnosed in the Veterans Health Administration (VHA).MethodMCS participants were included in the analytic sample if they responded to the 2013 survey, were separated from military service, and utilized VHA care for at least 2 years. HLB exposure was assessed using self-report of injury from a “blast/explosion/bullet” in the 2013 survey; LLB risk was determined using military occupational specialty as a proxy. Clinical diagnoses of five TBI severity levels (e.g., mild, penetrating), 22 TBI-related conditions (e.g., tinnitus, dementia/delirium, fatigue) and 10 mental health conditions (e.g., adjustment, bipolar, schizophrenia) were identified using ICD diagnosis codes. Modified Poisson regression with robust error variance was used to examine the relationships between HLB, LLB, and their interaction, adjusting for demographic and military characteristics for each diagnosis of interest.ResultsStatistically significant associations were found between HLB and several TBI diagnoses, TBI-related conditions, and mental health conditions. LLB exposure was associated with only one TBI condition, eight TBI-related conditions, and two mental health conditions. In addition, significant interactions between HLB and LLB were observed for two TBI-related conditions and four mental health conditions.ConclusionThis study contributes to the growing body of evidence on the long-term effects of BOP on brain health. These findings may inform policy development and educational resources, provide metrics to calculate the potential financial burden on the VHA and increase understanding of long-term health outcomes associated with blast exposure. By utilizing a prospective design and examining VHA diagnoses, the research highlights the potential enduring effects of blast exposure that may continue to require healthcare services after military separation.

STUDY OBJECTIVES:This study examined associations between filled prescription medications (FPMs) and sleep duration, insomnia, and sleep apnea (SA). METHODS:Active-duty service members (SMs) (n = 20,819) completed a questionnaire on sleep, demographics, and lifestyle characteristics and permitted access to their pharmacy and medical records 6-months before questionnaire completion. FPMs were classified by American Hospital Formulary System Pharmacologic-Therapeutic Classification System (PTCS) codes and compared across sleep durations of ≥7, 5-6, and ≤4 h and among those with and without diagnosed insomnia and SA. RESULTS:Compared to SMs reporting ≥7 h sleep, those reporting 5-6 and ≤4 h had 1.19 (95 %confidence interval [95 %CI] = 1.12-1.27) and 1.69 (95 %CI = 1.45-1.97) times higher odds of a FPM, respectively, after adjustment for demographics and lifestyle characteristics. Compared to SMs reporting ≥7 h sleep, those reporting 5-6 h had higher adjusted odds of FPMs in 10 of 20 PTCS codes--particularly electrolyte/caloric/water-balance agents--and those reporting ≤4 h had higher odds in 13 of 20 PTCS codes--particularly cardiovascular and central nervous system (CNS) agents. SMs with insomnia or SA had 8.66 (95 %CI = 5.89-12.71) and 3.46 (95 %CI = 2.90-4.12) higher adjusted odds of an FPM compared to those without insomnia or SA, respectively. SMs with insomnia or SA had higher adjusted odds of FPMs in 16 and 18 of 20 PTCS codes compared to those without these diagnoses. Cardiovascular and CNS agents were most prevalent in both sleep-disordered groups. CONCLUSION:Filling prescriptions in many different classes of medications increased as sleep duration decreased and was higher among SMs with diagnosed insomnia or SA.

Objective: To describe and quantify the prevalence and risk of deployment and nondeployment service-related traumatic brain injury (TBI) among participants of the Millennium Cohort Study. Setting: Survey data. Participants: 28 759 Millennium Cohort Study participants who were active duty, Reserves, or National Guard at the time of the survey. Design: Cross-sectional secondary data analysis. Main Measures: Estimates of prevalence and rates of TBI were calculated. Multivariable Poisson regression estimated rate ratios of TBI overall and stratified by deployment and nondeployment settings. Results: The rate of TBI over the 362 535 person-years (PY) was 2.95 p/100 PY. the nondeployment rate was 2.15 p/100 PY, with a significantly higher rate (11.38 p/100 PY) in deployment settings. Bullets/blasts were the most common TBI mechanisms in deployed settings, while sports/physical training and military training were common in nondeployed settings. Conclusions: The risk of TBI as well as its mechanism varies by deployment and nondeployment, suggesting that targeted prevention strategies are needed to reduce the risk for TBI among military personnel based on their deployment status.

This longitudinal study examined associations between chronic medical conditions (CMCs) and persistent dietary supplement (DS) use. On two separate occasions, 1.3 ± 0.2 years apart, military service members (SMs) (n = 5778) completed identical questionnaires concerning their DS use in the past 6 months and their demographic and lifestyle characteristics. Medical conditions were obtained from a medical surveillance system six months before the first questionnaire and during the period between questionnaires. Diagnoses were grouped into 19 major (largely systemic) and 9 specific CMCs. Conditions diagnosed in both periods (CMCs) were examined in relation to DS use reported on both questionnaires (persistent DS use). After adjustment for demographic and lifestyle factors, higher odds of persistent DS use were found in 7 of the 19 major CMCs and 5 of the 9 specific CMCs. SMs with a CMC had 1.25 (95% confidence interval [95%CI] = 1.10–1.41) higher adjusted odds of persistent DS use. The three specific CMCs with the highest adjusted odds of persistent DS use were anxiety (odds ratio [OR] = 2.30, 95%CI = 1.36–3.89), depression (OR = 2.12, 95%CI = 1.20–3.73), and gastroesophageal reflux disease (OR = 2.02, 95%CI = 1.02–4.04). Among DS categories, participants with a CMC had higher adjusted odds of persistent vitamins or mineral use (OR = 1.31, 95% CI = 1.12–1.53). Participants with CMCs had a higher prevalence of persistent DS use, especially individual vitamin and mineral use.

Over 70% of United States military service members (SMs) regularly use dietary supplements (DSs) and about 18% have reported adverse effects (AEs) associated with use. This investigation examined longitudinal changes in AEs reporting among DS users. On two separate occasions 1.3 +/- 0.2 years apart (mean +/- standard deviation), 5778 SMs completed identical questionnaires on DS use and associated AEs. Among SMs reporting DS use >= 1 time/week, >= 1 AE was reported by 19% and 15% in the baseline and follow-up phases, respectively. The risk of reporting DS use at follow-up was similar among those reporting and not reporting AEs at baseline for most DS categories including prohormones, proteins/amino acids, individual vitamins and minerals, multivitamin/multiminerals, herbals, fish oils, joint health products, and other DSs. An exception was combination products where those reporting AEs at baseline had an increased risk of use at follow-up (risk ratio = 1.13, 95% confidence interval = 1.06 -1.09). Those reporting AEs at baseline and continuing DS use in the follow-up were more likely to report AEs at follow-up compared to those not reporting baseline AEs. In conclusion, AEs reported at baseline did not deter many participants from using DSs in the follow-up period, and many SMs reporting AEs at baseline continued reporting them at follow-up.

Previous studies investigating temporal changes in dietary supplement (DS) use have used representative samples but have not followed the same cohort over time. This study investigated longitudinal patterns of changes in DS use and factors associated with discontinuing DS use in a single group of active-duty United States military service members (SMs). SMs (n = 5778) completed two identical questionnaires on their DS use and demographic/lifestyle characteristics an average ± standard deviation 1.3 ± 0.2 years apart. Prevalences of reported DS use ≥1 times/week in the baseline (BL) and follow-up (FU) phases were: any DS, BL = 77%, FU = 78%; multivitamins/multiminerals (MVM), BL = 50%, FU = 48%; individual vitamins/minerals, BL = 33%, FU 35%; proteins/amino acids, BL = 43%, FU = 39%; combination products, BL = 44%, FU = 37%; prohormones, BL = 5%, FU = 4%; herbal products, BL = 23%, FU = 21%; joint health products, BL = 12%, FU = 12%; fish oils, BL = 25%, FU = 23%; other DSs, BL = 17%, FU = 17%. Among BL users, the proportions reporting use in the FU phase were: any DS 88%, MVM 74%, protein/amino acids 70%, individual vitamin/minerals 62%, combination products 62%, fish oils 61%, joint health products 57%, herbal products 50%, other DSs 50%, and prohormones 37%. Higher odds of discontinuing any DS use in the follow-up were associated with female gender, younger age, higher BMI, and less weekly resistance training. Overall, prevalence of DS use was relatively consistent in the two phases; however, the cohort changed their use patterns in the follow-up with some discontinuing use and others initiating use, thus maintaining use prevalence over the period. These findings have implications for repeated cross-sectional DS studies where different samples are followed over time.

IntroductionAlthough previous research suggests that overpressure exposure from either high-level blast (HLB) or low-level blast (LLB) are harmful to health, to date no large-scale studies with representative samples of military personnel have utilized prospective designs and self-reported measures to examine the relationships between blast exposure and health conditions. To address these limitations, this analysis of data from the Millennium Cohort Study (MCS), the largest and longest running study of U.S. service members and veterans, examined (1) whether single or repeated HLB exposure is associated with self-reported diagnoses of illness and injury, (2) whether repeated HLB is associated with greater risk than single HLB, (3) potential adverse consequences of LLB exposure using military occupation as a proxy, and (4) the combined effects of single or repeated HLB and LLB exposure.MethodMCS participants who completed the 2011–2013 survey (N = 138,949) were classified as having been exposed to “no,” “single,” or “repeated” HLB exposure, and into low or high risk of exposure to LLB based on occupation. Participants self-reported diagnosis of 45 medical conditions; newly reported diagnoses were regressed on single and repeated (vs. no) HLB, occupational risk of LLB, and relevant interactions using logistic regression.ResultsSingle and repeated HLB were associated with new onset of 25 and 29 diagnoses, respectively; repeated HLB exposure was associated with greater risk than single HLB exposure for five diagnoses (e.g., PTSD, depression). Occupational risk of LLB was associated with 11 diagnoses (e.g., PTSD, significant hearing loss). Additionally, 14 significant interactions were detected across 11 diagnoses.DiscussionFindings suggest that overpressure exposure (including single HLB, repeated HLB, and occupational risk of LLB) may increase the risks of self-reporting clinical diagnoses of PTSD, hearing loss, chronic fatigue syndrome, neuropathy-caused reduced sensation in the hands and feet, depression, vision loss, sinusitis, reflux, and anemia. Furthermore, the combination of HLB and LLB exposure may be associated with greater risk of migraines, PTSD, and impaired fecundity. These findings provide further evidence of the potential adverse consequences associated with overpressure exposure and underscore the necessity of public health surveillance initiatives for blast exposure and/or safety recommendations for training and operational environments.

Objectives: This cross-sectional study investigated self-reported sleep duration and its association with a comprehensive range of clinically-diagnosed medical condition categories (CDMCs), as well as the relationship between short sleep duration (<= 6 h) and demographic/lifestyle factors, among United States military service members (SMs). Methods: A stratified random sample of SMs (n = 20,819) completed an online questionnaire on usual daily hours of sleep and demographic/lifestyle characteristics. CDMCs for a six-month period prior to questionnaire completion were obtained from a comprehensive military electronic medical surveillance system and grouped into 33 CDMCs covering both broad and specific medical conditions. Prevalence of CDMCs was compared among three sleep duration categories (<4, 5-6 and >7 h). Results: SMs reported a mean +/- standard deviation of 6.3 +/- 1.4 h of sleep per day. After adjustment for demographic/lifestyle characteristics, shorter sleep duration was associated with higher odds of a medical condition in 25 of 33 CDMCs, with most (n = 20) demonstrating a dose-response relationship. The five CDMCs with the largest differences between <= 4 vs >= 7 h sleep were: diseases of the nervous system (odds ratio [OR] = 2.9, 95% confidence interval [95%CI] = 2.4-3.4), mental/behavioral diseases (OR = 2.7, 95%CI = 2.3-3.2), diseases of the musculoskeletal system (OR = 1.9, 95%CI = 1.6-2.1), diseases of the circulatory system (OR = 1.7, 95%CI = 1.3-2.2), and diseases of the digestive system (OR = 1.6, 95% CI = 1.2-2.0). Six hours of sleep or less was independently associated with older age, less formal edu-cation, race, Hispanic ethnicity, higher body mass index, smoking, and military service branch. Conclusions: In this young, physically active population, reporting shorter sleep duration was associated with a higher risk of multiple CDMCs. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons. org/licenses/by/4.0/).

INTRODUCTION:Traumatic brain injury (TBI) is an occupational health hazard of military service. Few studies have examined differences in military occupational categories (MOC) which take into consideration the physical demands and job requirements across occupational groups.METHODS:This study was approved by the University of Texas Health Science Center at Houston Institutional Review Board. Data for this cross-sectional study were obtained from the Naval Health Research Center's Millennium Cohort Study, an ongoing DoD study. Univariate analyses were employed to calculate frequencies and proportions for all variables. Bivariate analyses included unadjusted odds ratios (OR) and 95% CI for the association between all variables and TBI. Multivariable logistic regression was used to calculate adjusted ORs and 95% CIs to assess the association between MOC and TBI, adjusted for potential confounders: sex, race/ethnicity, rank, military status, branch of service, before-service TBI, and panel. Logistic regression models estimated odds of TBI for each MOC, and stratified models estimated odds separately for enlisted and officer MOCs.RESULTS:Approximately 27% of all participants reported experiencing a service-related TBI. All MOCs were statistically significantly associated with increased odds of service-related TBI, with a range of 16 to 45%, except for "Health Care" MOCs (OR: 1.01, 95% CI 0.91-1.13). Service members in "Infantry/Tactical Operations" had the highest odds (OR: 1.45, 95% CI 1.31-1.61) of service-related TBI as compared to "Administration & Executives." Among enlisted service members, approximately 28% reported experiencing a service-related TBI. Among enlisted-specific MOCs, the odds of TBI were elevated for those serving in "Infantry, Gun Crews, Seamanship (OR: 1.79, 95% CI 1.58-2.02)," followed by "Electrical/Mechanical Equipment Repairers (OR: 1.23, 95% CI 1.09-1.38)," "Service & Supply Handlers (OR 1.21, 95% CI 1.08-1.37)," "Other Technical & Allied Specialists (OR 1.21, 95% CI 1.02-1.43)," "Health Care Specialists (OR 1.19, 95% CI 1.04-1.36)," and "Communications & Intelligence (OR: 1.16, 95% CI 1.02-1.31)," compared to "Functional Support & Administration." Among officer service members, approximately 24% reported experiencing a service-related TBI. After adjustment the odds of TBI were found to be significant for those serving as "Health Care Officers" (OR: 0.65, 95% CI: 0.52-0.80) and "Intelligence Officers" (OR: 1.27, 95% CI: 1.01-1.61).CONCLUSIONS:A strength of this analysis is the breakdown of MOC associations with TBI stratified by enlisted and officer ranks, which has been previously unreported. Given the significantly increased odds of service-related TBI reporting within enlisted ranks, further exploration into the location (deployed versus non-deployed) and mechanism (e.g., blast, training, sports, etc.) for these injuries is needed. Understanding injury patterns within these military occupations is necessary to increase TBI identification, treatment, and foremost, prevention.Results highlight the importance of examining specific occupational categories rather than relying on gross categorizations, which do not account for shared knowledge, skills, and abilities within occupations. The quantification of risk among enlisted MOCs suggests a need for further research into the causes of TBI.

Traumatic brain injury (TBI) is prevalent among active duty military service members, with studies reporting up to 23% experiencing at least one TBI, with 10-60% of service members reporting at least one subsequent repeat TBI. A TBI has been associated with an increased risk of cumulative effects and long-term neurobehavioral symptoms, impacting operational readiness in the short-term and overall health in the long term. The association between multiple TBI and post-concussive symptoms (PCS), however, defined as symptoms that follow a concussion or TBI, in the military has not been adequately examined. Previous studies in military populations are limited by methodological issues including small sample sizes, the use of non-probability sampling, or failure to include the total number of TBI. To overcome these limitations, we examined the association between the total lifetime number of TBI and total number of PCS among U.S. active duty military service members who participated in the Millennium Cohort Study. A secondary data analysis was conducted using the Millennium Cohort Study's 2014 survey (n = 28,263) responses on self-reported TBI and PCS (e.g., fatigue, restlessness, sleep disturbances, poor concentration, or memory loss). Zero-inflated negative binomial models calculated prevalence ratios (PRs) and 95% confidence intervals (CIs) for the unadjusted and adjusted associations between lifetime TBIs and PCS. A third of military participants reported experiencing one or more TBIs during their lifetime with 72% reporting at least one PCS. As the mean number of PCS increased, mean lifetime TBIs increased. The mean number of PCS by those with four or more TBI (4.63) was more than twice that of those with no lifetime TBI (2.28). One, two, three, and four or more TBI had 1.10 (95% CI: 1.06-1.15), 1.19 (95% CI: 1.14-1.25), 1.23 (95% CI: 1.17-1.30), and 1.30 times (95% CI: 1.24-1.37) higher prevalence of PCS, respectively. The prevalence of PCS was 2.4 (95% CI: 2.32-2.48) times higher in those with post-traumatic stress disorder than their counterparts. Active duty military service members with a history of TBI are more likely to have PCS than those with no history of TBI. These results suggest an elevated prevalence of PCS as the number of TBI increased. This highlights the need for robust, longitudinal studies that can establish a temporal relationship between repetitive TBI and incidence of PCS. These findings have practical relevance for designing both workplace safety prevention measures and treatment options regarding the effect on and from TBI among military personnel.

ABSTRACT:Poh, PYS, Sessoms, PH, Haluch, KS, and Trone, DW. Assessing injury susceptibility at Marine Corps Recruit Depot, San Diego, California. J Strength Cond Res 37(7): 1530-1536, 2023-Marine Corps Recruit Depot (MCRD) recruits undergo demanding training. Musculoskeletal injury (MSKI) accounts for attrition and graduation delays. Functional tests, such as Functional Movement Screen (FMS), Y-Balance Test-Lower Quarter (YBT-LQ), and ankle dorsiflexion range of motion (AD-ROM), may identify individuals at greater MSKI risk. This study tested the hypothesis that functional assessments may inform injury prediction. Male recruits ( N = 407; mean ± SD : age, 20 ± 2 years) performed baseline functional tests. Marine Corps Recruit Depot staff tracked MSKI and graduation outcomes. The chi-square test of independence (individual FMS exercises) and Mann-Whitney U (FMS composite score) test examined the relationship between FMS and MSKI incidence. One-way analysis of variance compared YBT-LQ and AD-ROM with MSKI incidence. Twelve recruits (3%) incurred a lower extremity MSKI and were dropped. Of those 12, 9 had a delayed graduation, and 3 separated from enlistment. The level of significance was set at p < 0.10 to identify between-group differences (yes-MSKI vs. no-MSKI). Functional movement screen composite score ( p = 0.064), hurdle step ( p = 0.059), and trunk stability ( p = 0.001) were lower in yes-MSKI. Y-Balance Test-Lower Quarter anterior direction difference between legs ( p = 0.011) and AD-ROM right side ( p = 0.055) was greater in yes-MSKI. Odds ratios (OR) were calculated using cut-off scores, with strong odds of sustaining MSKI with FMS trunk stability score <2 (OR: 7.56, 95% confidence interval [CI]: [2.32, 24.61]) and YBT-LQ anterior difference >6.25 cm (OR: 6.38, 95% CI: [1.98, 20.55]). Recruits who incurred MSKI had scores that indicated lesser mobility and stability of the lower extremity, providing preliminary evidence that when assessed together, FMS, YBT-LQ, and AD-ROM, may have predictive value for identifying those at MSKI risk.

BACKGROUND:A high BMI is associated with various medical conditions, notably type 2 diabetes, cardiovascular disease, and mental health disorders. In the US military, BMI increased linearly between 1975 and 2015. OBJECTIVE:This cross-sectional study investigated the associations between BMI and a comprehensive range of clinically diagnosed medical conditions (CDMCs) in US military service members (SMs). METHODS:A stratified random sample of SMs (n=26,177) completed an online questionnaire reporting their height, weight, and demographic/lifestyle characteristics. Medical conditions for 6 mo before questionnaire completion were obtained from a comprehensive military electronic medical surveillance system and grouped into 39 CDMCs covering both broad (largely systemic) and specific medical conditions. BMI was calculated as weight/height2 (kg/m2). The prevalence of CDMCs was compared among normal weight (<25.0 kg/m2), overweight (25.0-29.9 kg/m2), and obese (≥30 kg/m2) SMs. RESULTS:After multivariable adjustment for demographic/lifestyle characteristics, higher BMI was associated with higher odds of a diagnosed medical condition in 30 of 39 CDMCs, with all 30 displaying dose-response relationships. The 5 major CDMCs with the largest odds ratios comparing obese to normal weight were endocrine/nutritional/metabolic diseases (OR=2.67, 95%CI=2.24-3.15), nervous system diseases (odds ratio [OR]=2.59, 95%CI=2.32-2.90), circulatory system diseases (OR=2.56, 95%CI=2.15-3.06), musculoskeletal system diseases (OR=1.92, 95%CI=1.76-2.09), and mental/behavioral disorders (OR=1.69, 95%CI=1.51-1.90). Compared with normal weight SMs, overweight or obese SMs had a higher number of CDMCs (1.8±1.9 vs. 2.0±2.0 and 2.5±2.3, mean ± standard deviation, respectively, P<0.01). CONCLUSIONS:In a young, physically active population, higher BMI was associated with a host of medical conditions, even after adjustment for demographic/lifestyle characteristics. The US Department of Defense should improve nutrition education and modify other factors that contribute to overweight and obesity. This study demonstrates that the medical burden of obesity is substantial in overweight and obese SMs.

Background Sport-related nutritional supplements (SRNS) include sport drinks, sport bars, and sport gels. This investigation examined temporal patterns in SRNS use and adverse effects (AEs) reported by a single cohort of United States active-duty service members (SMs) surveyed before and during the coronavirus disease 2019 (COVID-19) pandemic.Methods A stratified random sample (n = 22,858) of SMs (Air Force, Army, Navy, and Marine Corps) who completed a questionnaire on their SRNS use and AE experiences and were still on active duty were asked to complete the identical questionnaire on a second occasion. Twenty-five percent of successfully contacted SMs completed both questionnaires (n = 5,778) and were included in this investigation. The average +/- standard deviation time between questionnaires was 1.3 +/- 0.2 years.Results Prevalence of reported SRNS use >= 1 time/week in the baseline (BL) and follow-up (FU) phases were as follows: any SRNS: BL = 46%, FU = 41%; sport drinks: BL = 31%, FU = 28%; sport bars: BL = 30%, FU = 24%; sport gels: BL = 4%, FU = 4%. Reported weekly aerobic and resistance training durations were reduced in the FU period (8% and 26%, respectively). The proportion of SMs reporting SRNS use in both study phases was as follows: any SRNS = 62%, sport drinks = 54%, sport bars = 50%, sport gels = 35%. Prevalence of reported AEs in the BL and FU phases were as follows: any SRNS: BL = 1.9%, FU = 1.9%; sport drinks: BL = 1.0%, FU = 1.3%; sport bars: BL = 1.7%, FU = 1.4%; sport gels: BL = 3.3%, FU = 2.5%. The proportion of SMs reporting AEs in both phases was as follows: any SRNS = 14%, sport drinks = 11%, sport bars = 17%, sport gels = 0%.Conclusions Overall SRNS use prevalence decreased slightly in the FU period, possibly because of reduced physical training related to military restrictions imposed during the emergence of COVID-19 between surveys. A large proportion of SMs reported changing their use patterns in the FU with some discontinuing use and others initiating use. The AE incidence was similarly low in the BL and FU phases, and few SMs reported AEs in both phases suggesting AEs were transitory. AE reporting for SRNSs was much lower than previously found for dietary supplements, possibly because of greater government regulatory control over SRNSs.

Objective:This study examined associations between multiple dietary supplement (DS) categories and medical conditions diagnosed by health professionals. Design:Cross-sectional. Setting:Volunteers completed an online questionnaire on DS use and demographic/lifestyle factors. Medical diagnoses were obtained from a comprehensive military electronic medical surveillance system and grouped into twenty-four clinically diagnosed medical conditions (CDMC). Participants:A stratified random sample of US service members (SM) from all military services (n 26 680). Results:After adjustment for demographic/lifestyle factors (logistic regression), higher risk was found for 92 % (22/24) of CDMC among individual vitamins/minerals users, 58 % (14/24) of CDMC among herbal users, 50 % (12/24) of CDMC among any DS users and 46 % (11/24) of CDMC among multivitamins/multiminerals (MVM) users. Among protein/amino acid (AA) users, risk was lower in 25 % (6/24) of CDMC. For combination products, risk was higher in 13 % (3/24) of CDMC and lower in 8 % (2/24). The greater the number of CDMC, the higher the prevalence of DS use in most DS categories except proteins/AA where prevalence decreased. Conclusions:Users in many DS categories had a greater number of CDMC, but protein/AA users had fewer CDMC; results for combination products were mixed. These data indicate those with certain CDMC were also users in some DS categories, especially individual vitamins/minerals, herbals and MVM. Data are consistent with the perception that use of DS enhances health, especially in those with CDMC. Protein/AA and combination product users were more likely to be younger, more physically active men, factors that likely reduced CDMC.

Background Although representative data on caffeine intake in Americans are available, these data do not include US service members (SMs). The few previous investigations in military personnel largely involve convenience samples. This cross-sectional study examined prevalence of caffeine consumers, daily caffeine consumption, and factors associated with caffeine use among United States active duty military service members (SMs). Methods A stratified random sample of SMs were asked to complete an on-line questionnaire on their personal characteristics and consumption of caffeinated products (exclusive of dietary supplements). Eighteen percent ( n = 26,680) of successfully contacted SMs ( n = 146,365) completed the questionnaire. Results Overall, 87% reported consuming caffeinated products ≥1 time/week. Mean ± standard error per-capita consumption (all participants) was 218 ± 2 and 167 ± 3 mg/day for men and women, respectively. Caffeine consumers ingested 243 ± 2 mg/day (251 ± 2 mg/day men, 195 ± 3 mg/day women). On a body-weight basis, men and women consumed respectively similar caffeine amounts (2.93 vs 2.85 mg/day/kg; p = 0.12). Among individual caffeinated products, coffee had the highest use (68%), followed by sodas (42%), teas (29%), energy drinks (29%) and gums/candy/medications (4%). In multivariable logistic regression, characteristics independently associated with caffeine use (≥1 time/week) included female gender, older age, white race/ethnicity, higher body mass index, tobacco use or former use, greater alcohol intake, and higher enlisted or officer rank. Conclusion Compared to National Health and Nutrition Examination Survey data, daily caffeine consumption (mg/day) by SMs was higher, perhaps reflecting higher mental and physical occupational demands on SMs.

Dietary supplements (DSs) are used by 50% of Americans and 70% of United States military service members (SMs); some have adverse effects (AEs). This cross-sectional investigation examined AEs associated with specific DSs. A stratified random sample of SMs from the Air Force, Army, Marine Corps, and Navy was obtained. Volunteers completed a questionnaire reporting AEs for 96 generic and 62 specific DSs. The highest prevalence (≥1 AE) in specific DS categories was 35% prohormones, 33% weight loss supplements, 26% pre/post workout supplements, 14% herbal products, 12% multivitamin/multiminerals, 11% protein/amino acids, 9% muscle building supplements, 7% other DSs, 6% joint health products, and 5% individual vitamins/minerals. Specific DSs of concern (with proportion reporting AEs) included: Libido Max® (35%), Hydroxycut Hardcore® (33%), OxyElite® (33%), Roxylean® (31%), Growth Factor 9® (30%), Super HD® (29%), Hydroxycut Advanced® (29%), Lipo 6® (28%), The Ripper® (27%), Test Booster® (27%), Xenadrine Xtreme Thermogenic® (27%), C4 Extreme® (26%), and C4 Original® (25%). Products marketed for weight loss, use before/after workout, and prohormones had the highest AE prevalence. DSs can contain substances with independent/additive AEs and/or interact with other ingredients or prescribed medications. Methods described here could provide a continuous surveillance system detecting dangerous DSs entering the market.