Active Duty Navy Research Articles

Autoimmune Thyroid Disease: An Unusual Cause or Confounder of Vertigo.

Over the last decade, the published literature investigating the association between thyroid function and recurrent or persistent vertigo has become more robust. We present an interesting case of persistent vertigo in a healthy 31-year-old active duty Navy pilot who was restricted from operating single-pilot rotary aircraft because of the severity of her symptoms. During her work-up, she was newly diagnosed with autoimmune thyroid disease and started on thyroid hormone supplementation. Adequately treating her underlying thyroid disease was associated with resolution of dizzy symptoms and she was granted a waiver to return to flying. This case highlights the importance of autoimmune thyroid disease as a less common but important diagnosis to consider in the broad differential for vertigo. This is especially relevant to the military population since dizziness contributes to spatial disorientation for aviators and can be highly debilitating for warfighters. Astutely diagnosing and treating underlying causes of dizziness may allow service members to return to physically demanding and mentally arduous duties, improving overall military readiness.

The Impact of COVID-19 on Health Behavior Engagement and Psychological and Physical Health Among Active Duty Military Enrolled in a Weight Management Intervention: An Exploratory Study.

The COVID-19 pandemic profoundly affected the health and well-being of people globally. Some studies suggest individuals with overweight or obesity may have been more adversely impacted by pandemic restrictions. Additionally, military personnel may have been more vulnerable to stress during the pandemic because of job demands (e.g., work in close quarters). Our research group was conducting a randomized clinical trial of a weight management intervention in active duty military personnel with overweight or obesity when the COVID-19 pandemic struck. Thus, we collected additional pandemic-related data from participants enrolled during the COVID-19 pandemic and conducted exploratory analyses to understand how the pandemic affected their stress levels and perceived abilities to engage in health behaviors like exercise and healthy eating. The aims of this exploratory study were to: (1) assess associations between pandemic-related stress and health behaviors with body fat percentage (BF%) and psychological and physical health, and (2) explore how pandemic-related stress and health behaviors affected BF% during and after the intervention. A total of 29 active duty Navy personnel (55% female, 69% White) were enrolled after the onset of pandemic restrictions and completed measures assessing pandemic-related stress and health behaviors as well as measures of general psychological and physical health before the intervention. BF% was collected at 5 timepoints, including baseline, during, and following the intervention. Bivariate correlations assessed associations at baseline. Linearmixed-effects longitudinal models explored how pandemic-related stress and health behaviors affected BF%. Post-hoc analyses evaluated the effects of pandemic factors on BF% at each timepoint. Most participants perceived of the pandemic as increasing stress and detracting from their abilities to engage in health behaviors (i.e., exercise and healthy eating). Higher pandemic stress was significantly associated with reporting exercise and healthy eating as more difficult, worse overall health, and more anxiety and general stress. Reporting exercise as harder during the pandemic also was associated with more psychological distress at baseline. A linearmixed- effects model controlling for age, sex, and number of intervention sessions attended revealed endorsing "exercise as harder" was associated with higher BF%. Post-hoc regression analyses revealed rating "exercise as harder" significantly predicted higher BF% 3 months post-intervention (B = 0.65, P = .01), whereas pandemic stress was not significantly associated with higher BF% at 3 month (B =0.14, P = .08) or 6 month (B = 0.21, P = .09) follow-up. As expected, most participants perceived of the pandemic as heightening stress and interfering with engagement in health behaviors. It is possible that pandemic-related stress may have exacerbated weight gain-promoting behaviors and/or interfered with achievement of desired weight management outcomes. Outside the context of the pandemic, it may be beneficial for healthcare providers to screen individuals for stress and perceptions of ease of engagement in health behaviors before enrollment in a weight management intervention. Further, tailoring interventions to mitigate stress and promote perceptions of ease in engaging in health behaviors may promote better weight management outcomes.

External Validation and Updating of a Statistical Civilian-Based Suicide Risk Model in US Naval Primary Care

Suicide remains an ongoing concern in the US military. Statistical models have not been broadly disseminated for US Navy service members. To externally validate and update a statistical suicide risk model initially developed in a civilian setting with an emphasis on primary care. This retrospective cohort study used data collected from 2007 through 2017 among active-duty US Navy service members. The external civilian model was applied to every visit at Naval Medical Center Portsmouth (NMCP), its NMCP Naval Branch Health Clinics (NBHCs), and TRICARE Prime Clinics (TPCs) that fall within the NMCP area. The model was retrained and recalibrated using visits to NBHCs and TPCs and updated using Department of Defense (DoD)-specific billing codes and demographic characteristics, including expanded race and ethnicity categories. Domain and temporal analyses were performed with bootstrap validation. Data analysis was performed from September 2020 to December 2022. Visit to US NMCP. Recorded suicidal behavior on the day of or within 30 days of a visit. Performance was assessed using area under the receiver operating curve (AUROC), area under the precision recall curve (AUPRC), Brier score, and Spiegelhalter z-test statistic. Of the 260 583 service members, 6529 (2.5%) had a recorded suicidal behavior, 206 412 (79.2%) were male; 104 835 (40.2%) were aged 20 to 24 years; and 9458 (3.6%) were Asian, 56 715 (21.8%) were Black or African American, and 158 277 (60.7%) were White. Applying the civilian-trained model resulted in an AUROC of 0.77 (95% CI, 0.74-0.79) and an AUPRC of 0.004 (95% CI, 0.003-0.005) at NBHCs with poor calibration (Spiegelhalter P < .001). Retraining the algorithm improved AUROC to 0.92 (95% CI, 0.91-0.93) and AUPRC to 0.66 (95% CI, 0.63-0.68). Number needed to screen in the top risk tiers was 366 for the external model and 200 for the retrained model; the lower number indicates better performance. Domain validation showed AUROC of 0.90 (95% CI, 0.90-0.91) and AUPRC of 0.01 (95% CI, 0.01-0.01), and temporal validation showed AUROC of 0.75 (95% CI, 0.72-0.78) and AUPRC of 0.003 (95% CI, 0.003-0.005). In this cohort study of active-duty Navy service members, a civilian suicide attempt risk model was externally validated. Retraining and updating with DoD-specific variables improved performance. Domain and temporal validation results were similar to external validation, suggesting that implementing an external model in US Navy primary care clinics may bypass the need for costly internal development and expedite the automation of suicide prevention in these clinics.

Vitamin D status in active duty Navy military personnel: a systematic review

ObjectivesActive duty Navy military personnel are prone to vitamin D deficiency due to an occupational environment detrimental to sunlight exposure. The main objective of this systematic review is to provide...

Hyperbaric oxygen treatment for paracentral acute middle maculopathy: a case study

A 47-year-old active-duty Navy diver with a complicated past medical history which resulted in his designation as not physically qualified (NPQ) for diving duty in 2016 presented on 07 May 2021 complaining of left-sided blurred vision. On exam by the attending undersea medical officer he was found to have a left upper inner and upper outer quadrant visual field defect along with a central scotoma. Urgent referral to ophthalmology ruled out retinal detachment but resulted in an initial diagnosis of a left branch retinal artery occlusion without embolus. Considering this a variant of central retinal artery occlusion, hyperbaric oxygen (HBO2) therapy was initiated approximately 12 hours after symptom onset, resulting in complete, though temporary, resolution of the visual field defect. He reported that after completion of his first HBO2 treatment, his visual field deficit began to return, but the deficit again resolved after initiating surface oxygen therapy between HBO2 treatments. After two days of continuous surface oxygen and daily HBO2 treatments, which kept his visual field defect minimized, his deficits changed to a persistent left lateral peripheral defect and a recurrent central nasal defect. At this time, his periodic ophthalmology evaluation revised his diagnosis to cilioretinal artery occlusion (CrAO). Further evaluation by ophthalmology revealed retinal changes consistent with a secondary diagnosis of paracentral acute middle maculopathy (PAMM), an ophthalmologic condition only recently defined in the literature (2013) [10] secondary to advances in retinal imaging technology. This case is presented to share the findings of this complicated case and to postulate a benefit from the use of HBO2 for cilioretinal artery occlusion with PAMM.

The Association of Skin Cancer Prevention Knowledge, Sun-Protective Attitudes, and Sun-Protective Behaviors in a Navy Population.

U.S. Navy service members are primarily between the ages of 18 and 30 years and often required to be outside for extended periods of time in geographical locations with increased and often unfamiliar ultraviolet indexes that collectively increase their risk for skin cancer. Skin cancer is the country's most common form of cancer, yet there is a paucity of skin cancer prevention literature, especially within the U.S. Navy. The purpose of this study was to describe skin cancer risk and skin cancer prevention "cues-to-action" and to determine if skin cancer prevention knowledge was associated with sun-protective attitudes (e.g., prevention perceptions, benefits, threats, barriers, and sun-protective behavior self-efficacy) and sun-protective behaviors (e.g., wearing long sleeve shirts and using sunscreen and not deliberately exposing skin for a tan) in a Navy population. A cross-sectional, descriptive, correlational design was utilized, and the study approval was obtained by the Naval Medical Center Portsmouth Institutional Review Board. Two-hundred twenty-nine active duty Navy service members aged 18-30 years who presented to primary care for their periodic health assessment completed the Brief Skin Cancer Risk Assessment and the Skin Cancer Survey. Descriptive statistics were utilized to assess service members' perceptions and knowledge regarding skin cancer prevention along with sociodemographic characteristics. The Spearman rank-order correlation and the Mann-Whitney U test were used to assess associations. P-values <.05 were used to determine statistical significance. Skin cancer prevention knowledge was significantly related to sun-protective behavior self-efficacy (r = 0.218, P = .001), benefits (r = 0.271, P ≤ .001), sun protection behaviors (r = 0.152, P = .024), skin cancer risk (r = 0.256, P = .001), current frequency of high-risk sun behavior (r = 0.183, P = .006), past frequency of high-risk sun behavior (r = 0.219, P = .001), sun exposure (U = 4,813.50, P = .005), tanning bed use (U = 3,154.50, P = .031), and training (U = 4,099.50, P = .005). Integrating skin cancer education into primary care visits (i.e., periodic health assessments) may improve Navy service members' modifiable sun-protective attitudes and behaviors and may contribute to lowering future skin cancer rates.

Unintended Pregnancy and Abortion in the US Navy, 2016

BackgroundThe unintended pregnancy rate in the US military is higher than among civilians. While 42% of unintended pregnancies end in abortion among civilian women, there are no data on the prevalence of abortion in the military overall or by service branch.ObjectiveThis analysis was conducted to estimate unintended pregnancy rates and the percentage of unintended pregnancies that resulted in abortion among active-duty US Navy members aged 44 years or younger reporting female gender in 2016.DesignCross-sectional survey data from the 2016 Navy Pregnancy and Parenthood Survey, collected from August to November 2016.ParticipantsOur sample included 3,423 active-duty US Navy members aged 44 years or younger reporting female gender, generated from a stratified random sample of 38% of all active-duty Navy women in pay grades E2-E9 and O1-O5 in 2016; the survey had a 20% response rate for females.Main MeasuresWe calculated pregnancy and unintended pregnancy rates, the percentage of pregnancies that were unintended, and the percentage of unintended pregnancies resulting in birth and abortion in the prior fiscal year.Key ResultsOverall, the self-reported unintended pregnancy rate was 52 per 1,000 participants and 38.1% of pregnancies were unintended. The adjusted unintended pregnancy rate accounting for abortion underreporting was 68 per 1,000 participants. Unintended pregnancy rates were highest among individuals who were younger (aged 18–24) and in enlisted pay grades, compared to their counterparts. Six percent reported their unintended pregnancy resulted in abortion. Six respondents reported becoming pregnant while deployed; none of these pregnancies resulted in abortion.ConclusionsIn this first study to report on abortion prevalence among US servicemembers, we found the proportion of unintended pregnancies resulting in abortion among a sample of US Navy members in 2016 was much lower than civilians, yet unintended pregnancy rates were higher.

Initial Assessment of a Regional Military-Civilian Partnership on Trauma Surgery Skills Sustainment.

Trauma surgery skills sustainment and maintenance of combat readiness present a major problem for military general surgeons. The Military Health System (MHS) utilizes the knowledge, skills, and abilities (KSA) threshold score of 14,000 as a measure of annual deployment readiness. Only 9% of military surgeons meet this threshold. Most military-civilian partnerships (MCPs) utilize just-in-time training models before deployment rather than clinical experiences in trauma at regular intervals (skills sustainment model). Our aim is to evaluate an established skills sustainment MCP utilizing KSAs and established military metrics. Three U.S. Navy active duty general surgeons were embedded into an urban level-1 trauma center taking supervised trauma call at regular intervals prior to deployment. Operative density (procedures/call), KSA scores, trauma resuscitation exposure, and combat casualty care relevant cases (CCC-RCs) were reviewed. During call shifts with a Navy surgeon present an average 16.4 trauma activations occurred; 32.1% were category-1, 27.6% were penetrating, 72.4% were blunt, and 33.8% were admitted to the intensive care unit. Over 24 call shifts of 24 hours in length, 3 surgeons performed 39 operative trauma cases (operative density of 1.625), generating 11,683 total KSA points. Surgeons 1, 2, and 3 generated 5109, 3167, and 3407 KSA points, respectively. The three surgeons produced a total of 11,683 KSA points, yielding an average of 3,894 KSA points/surgeon. In total, 64.1% of operations fulfilled CCC-RC criteria. Based on this initial evaluation, a military surgeon taking two calls/month over 12 months through our regional skills sustainment MCP can generate more than 80% of the KSA points required to meet the MHS KSA threshold for deployment readiness, with the majority being CCC-RCs. Intangible advantages of this model include exposure to multiple trauma resuscitations while possibly eliminating just-in-time training and decreasing pre-deployment requirements.

Vitamin D status in the active duty Navy military personnel: protocol for a systematic review

IntroductionVitamin D is critical for bone health and its deficiency has been linked to increased incidence and severity of multiple diseases. Even so, vitamin D inadequacy is a major public...

Characteristics of Active Duty Service Members Referred to the Navy's Weight-Management Program.

Rates of overweight and obesity have increased in the military, particularly in the U.S. Navy. While the Navy has implemented weight-management programs like ShipShape, findings on the effectiveness of these programs are mixed. Further knowledge on the characteristics of service members (SMs) who participate in these programs may help inform course curricula and improve outcomes. This study aimed to (1) examine characteristics of SMs referred to the Navy's ShipShape program at a large military treatment facility, (2) compare these characteristics among SMs who did and did not enroll in a randomized clinical trial of ShipShape (ShipShape study participants), and (3) compare demographic and health characteristics of ShipShape study participants to that of a random and similarly sized sample of Navy SMs who responded to the 2015 DoD Health-Related Behaviors Survey (HRBS). Data from active duty Navy SMs referred to the ShipShape program at a large military treatment facility were evaluated (n = 225). A subset of these SMs enrolled in the ShipShape study (n = 187). Among enrolled SMs, data from 147 who completed all measures were compared to that of HRBS respondents. Univariate ANOVA and chi-square analyses were used to examine (1) demographic and motivational differences between SMs who did and did not enroll in the ShipShape study and (2) differences in demographics and medical and mental health conditions between ShipShape study participants and Navy HRBS respondents. The majority of SMs referred to ShipShape were female with an average age of 28.3 years. Compared to SMs who did not enroll in the ShipShape study (n = 38), ShipShape study participants were more likely to be female, less likely to be Hispanic, and had higher motivation and emotional eating scores. Compared to Navy HRBS respondents (n = 164), ShipShape study participants (n = 147) were younger, more likely to be female, non-Hispanic, enlisted, and obese. Further, ShipShape study participants reported significantly fewer medical health conditions but higher rates of probable depression, anxiety, and PTSD and were more likely to report receiving current mental health treatment than HRBS respondents. Overweight or obese SMs seeking weight loss in the ShipShape study were relatively young, female, non-Hispanic, motivated, but with greater emotional eating. ShipShape study participants endorsed few medical health conditions but had higher rates of probable mental health conditions compared to the HRBS sample. These findings suggest that SMs referred to Navy weight-management programs are likely experiencing comorbid mental health conditions which may interfere with the effectiveness of their weight loss efforts. The descriptive nature of this study and the focus on Navy SMs in only one ShipShape program may decrease the generalizability of our findings to participants at other locations. Nonetheless, these findings demonstrate the potential need for Navy weight-management programs that incorporate mental health treatment and address the specific needs of female and diverse SMs. A more comprehensive curriculum could improve the results of weight-management efforts, increase SM quality of life and fitness and thereby operational readiness.

Trends in Surgical Case Volume During Pacific Partnership Missions Onboard USNS Mercy.

Since 2006, the U.S. Navy has conducted six Pacific Partnership (PP) missions throughout Southeast Asia on board the U.S. Naval Ship Mercy (T-AH 19). This study describes trends in overall and surgical specialty operative volumes to better understand the burden of surgical disease treated during these humanitarian and civic assistance (HCA) operations. This information can assist medical planners and surgical leaders involved in future humanitarian missions. Following approval from the Naval Medical Center San Diego Institutional Review Board, a retrospective review of surgical case data was performed for the six PP missions from 2006 to 2018. Data collected included patient demographics, Current Procedural Terminology codes, and surgical specialty. The primary outcome was surgical case volume per specialty. Secondary outcomes included surgical staffing per mission and overall trends in operative volume. A total of 3,826 operative procedures were performed during the study period. Mission years in which case volume for both general surgery and ophthalmology were below their respective medians were associated with the least total surgical services to host nations (HNs). The number of active duty Navy surgeons varied with each mission; however, the staffing for a PP mission generally included at least two general surgeons, one ophthalmologist, one plastic surgeon, one pediatric surgeon, one orthopedic surgeon, one otolaryngologist, one oral surgeon, one urologist, and one obstetrician-gynecologist. Case volume per surgeon was highest in 2006 (50 cases per surgeon) and decreased after 2006, reaching an all-time low during the 2018 PP mission (10 cases per surgeon). Pediatric surgery and plastic surgery had the highest average case volumes per surgeon at 58 and 46 cases per surgeon, respectively, while oromaxillofacial surgery and neurosurgery had the lowest average case volumes per surgeon at 9 and 14 cases per surgeon, respectively. Operative volume on military HCA missions is greatly influenced by the priorities of the HN, the mission focus, the number of individuals from the HN that present for screening, and the availability of personnel and resources available on the hospital ship. Future mission planning should optimize general surgery and ophthalmology staffing and essential equipment, as total mission case volumes were highly dependent upon the productivity of these two specialties. Careful determination of the surgical needs of HNs should serve as a guide for the selection of subspecialists to maximize effectiveness in future military HCA missions.

Viral Hepatitis C-Related Care in Active Duty and Reserve Service Members: A Retrospective Review.

Hepatitis C Virus (HCV) infection is a leading cause of chronic liver disease and hepatocellular carcinoma, and universal screening of all adults is recommended. Treatment with new direct antiviral agents are well tolerated and highly effective and decrease morbidity and mortality from HCV. The timely treatment of active-duty Service members (SMs) is essential to prevent complications of HCV and to ensure medical readiness and safety of the Department of Defense blood supply. We performed a retrospective review of the quality of care of Navy Active Duty (AD) and reserve SMs diagnosed with HCV to assess rates of successful treatment and compliance with national guideline recommendations and identify potential challenges to receiving curative HCV therapy. A retrospective chart review was completed on the health records of 54 AD and reserve US Navy SMs diagnosed with HCV. The records were reviewed for timeliness of subspecialty evaluation, achievement of sustained virologic response (SVR), and documentation of the completion of HCV-associated recommendations from national organizations and guidelines. Challenges and barriers to care were identified. Ninety-eight percent of AD and reserve Navy SMs diagnosed with HCV were prescribed treatment, 81% achieved an SVR after completing initial treatment, which reached 92% after initial nonresponders underwent a second round of treatment. Fifty percent of SMs experienced a delay in care due mostly to military-related obligations and patient noncompliance or both. There was a small number of delays in care as a result of prolonged notification of results and referral time. As HCV screening recommendations expand to include all adults, more HCV infections will be identified in both the active and reserve components. Modern HCV therapies are both relatively short in duration as well as curative, allowing for the restoration of medical readiness and military service retention. Despite these advantages, we identified challenges of effecting HCV cures in a mobile military population. We recommend centralized compliance monitoring of not only HCV force screening but also HCV treatment to ensure maximized military medical readiness.

Incidence and Mechanisms of Musculoskeletal Injuries in Deployed Navy Active Duty Service Members Aboard Two U.S. Navy Air Craft Carriers

This brief report describes the number and nature of cases of musculoskeletal pain and injury among sailors and marines presenting to the ship's physical therapist during recent, respective deployments of two U.S. Navy aircraft carriers. The case definition for this study was cases of work-limiting medical complaints involving the musculoskeletal system presenting, or referred, to the ship's physical therapy services for evaluation and treatment. The population for this study was drawn from ship's company from two Nimitz class carriers on their respective deployments. Potential subjects were recruited at their index visit for their complaint. Participants completed a survey of their symptoms while at the ship's medical department. Data for analysis consist of counts of cases, body part affected, self-reported mechanism of injury, age, and gender of the subject. Data were analyzed by generating descriptive tables. One hundred ninety-seven cases were captured across the two carriers. Injury to the low back was the most frequent (34%), followed by shoulder (25%) and knee (15%). Twenty one cases (11%) were reported to be exacerbation of previous injuries and the rest new injuries. Of the 176 new injury cases, 93 (53%) were of an insidious onset and the remainder had a specific, identifiable onset. Of the 82 cases with a specific identifiable onset, 38 cases (46%) occurred during participation in sport and exercise activity on board ship, and the remainder of the cases occurred during the performance of duty-related work. None of the cases required evacuation off of the ship. Care should be used interpreting the results since participants were volunteers and a small proportion of eligible subjects chose not to participate in the study. Nevertheless, our data are generally consistent with other studies of musculoskeletal injury on board U.S. Navy ships and are useful for health care planning purposes and for planning for future studies that may take place on board U.S. Navy vessels. The novel and important finding of this study suggests that sports and exercise activity on board ship may warrant a new area of attention for safety.

Buddy Care, a Peer-to-Peer Intervention: A Pilot Quality Improvement Project to Decrease Occupational Stress Among an Overseas Military Population.

Occupational stress can have a direct influence on worker safety and health. Navy medical professionals are known to neglect self-care, putting them at risk for deteriorations in psychological health that can lead to adverse patient outcomes. To support medical professionals, a peer-to-peer intervention called Buddy Care, embedded in Navy Medicine's Caregiver Occupational Stress Control (CgOSC) program, was evaluated. Strategies to prevent and better manage occupational stress are vital to improve the health care providers' abilities to cope with day-to-day stressors, which is crucial to maintaining mission readiness. The overarching aim of this quality improvement pilot project was to implement and evaluate Buddy Care and to provide context as an evidenced-based peer intervention and leadership tool at a military hospital in Guam. This project is the first to implement and evaluate Buddy Care intervention for an active duty U.S. Navy population stationed overseas. A convenience sample of 40 Navy active duty assigned to three inpatient units were offered Buddy Care intervention, which was introduced by conducting a Unit Assessment. A pre-test and 3- and 6-month post-test intervention design used a self-administered, 79-item CgOSC Staff Wellness Questionnaire which included five validated measures to assess the independent variable: (1) Response to Stressful Experience Scale, (2) Perception of Safety, (3) Horizontal Cohesion, (4) Perceived Stress Scale, and (5) Burnout Measure, short version. This project was determined as exempt by the Department of Navy Human Research Protection Program and did not require further review by the Institutional Review Board. Of the 40 questionnaires collected, 39 were partially completed. Paired sample t-tests were conducted between designated time-points to maximize the sample size and retain the repeated measures nature of the outcome variables. The small sample size allowed for statistical comparisons; however no statistically significant differences were found across the time-points. There was a large effect size for Perceptions of Safety and a medium effect size for Burnout Measure from baseline to 3 months, with both lowered at the 6 months. Although the sample size was too small to achieve statistical significance, the effect size analysis suggested that significance might be obtained with a larger sample. The small number of participants and missing data significantly limited the ability to identify reliable changes across time-points. Despite the lack of statistically significant findings, there was an unintended positive result. The Unit Assessment piqued the interest of other departments, and during the project period, 11 departments requested a Unit Assessment. Although there were no requests for Buddy Care intervention from the targeted sample, it was occurring an average of 40 times per month throughout the command. Replication of this project in a similar setting is encouraged so that Buddy Care can be further evaluated. Understanding the effectiveness of well-mental health programs that promote early intervention and prevention efforts may contribute to a psychologically tougher medically ready force. Shortly after project completion, a CgOSC Instruction was approved by the Navy Surgeon General, highlighting the importance of CgOSC and Buddy Care on the operational readiness of Navy Medicine.

Postpartum Fitness and Body Mass Index Changes in Active Duty Navy Women.

Active duty Navy women participate in biannual Physical Fitness Assessments (PFAs), which include height and weight measurements and a Physical Readiness Test (PRT). PFAs are waived during pregnancy and resume the cycle after 6 months following maternity leave. The purpose of this study was to compare changes in PFA results over time between women who had or did not have a live birth during the follow-up period, and identify characteristics of women with lower PFA results postpartum. This longitudinal study included 14,142 active duty Navy women, aged 19-40 years, with PFA results during July 2011-June 2015. Multivariable logistic regression, Stuart-Maxwell tests, and mixed effects modeling were used to examine changes in PRT scores and body mass index over time between women with and without a live birth during follow-up. All data were analyzed in 2017. This study was approved by the institutional review boards at the Uniformed Services University Office of Research and the Naval Health Research Center, and informed consent was waived in accordance with 32 CFR § 219.116(d). Postpartum women had increased odds of PRT failures (AOR = 3.88, 95% CI: 1.44-10.40) and lower PRT scores (AOR = 1.47, 95% CI: 1.12-1.92) up to 2.5 years postpartum, versus women without a live birth. Being enlisted, obese/overweight prepregnancy, and younger were risk factors for suboptimal PFA outcomes. Mean core strength and cardiovascular endurance, but not upper body strength, scores were significantly lower in postpartum women at 1 year postpartum versus women without a live birth. Our findings show that additional interventions may be needed to assist women in returning to prepregnancy fitness up to 1 year postpartum. Future studies should examine additional factors that may improve postpartum fitness in addition to enhancing maternity leave policies.

Human Physiologic Thermogenic Response to Resting Cold-Water Immersion: A Thorough Calorimetric Inquiry

PURPOSE: Navy Diver thermal protection, a primary concern in attempting or completing cold-water tasks, remains inadequate. Optimal heat distribution with minimal energy input is sought. Therefore, heating requirements that support thermal balance (TB) in various cold-water scenarios were quantified. METHODS: Nine active duty Navy personnel underwent four resting immersion scenarios in a temperature-controlled 4900-gallon water tank after donning the same full-body tubesuit calorimeter (for diver heat delivery and measurement), undergarments, and a dry suit (total 1.2 Clo). Each subject achieved TB (<2hrs immersion). TB was defined as temperature equilibrium where core and mean skin temperatures varied < 0.2°F over 20 minutes time. The four scenarios were combinations of the independent variables: 1) inlet tubesuit water temperature (89 and 102°F), and 2) immersion tank temperature (35 or 50°F). RESULTS: Metabolic compensation continuously increased over time (Fig 1a) in the 89°F tubesuit/35°F immersion temperature water group. At the fourth quartile time point (during achievement of thermal balance, Fig 1a - Fourth), subjects in the groups of greater tubesuit heat delivery (102°F) required significantly less metabolic activity than did the coldest scenario (89°F/35°F). Distal anatomical sites showed much lower temperatures than proximal sites (data not shown). Tubesuit heat delivery (Wattage) increased significantly (Fig 1b) with both greater tubesuit temperature (102°F vs 89°F) and in colder water immersion (35°F vs 50°F). Thermal balance was achieved in all scenarios thereby allowing steady-state assessment of heat input/extraction parameters. All * indicate p<0.05. CONCLUSIONS: Given that thermal balance was achieved over the course of each ≤ 2-hr exposure, results suggest that using a lower tubesuit perfusion temperature (89°F vs 102°F) requires less Wattage provided a sufficient metabolic response is activated during the immersion.Figure 1

Combat Readiness, Harm Aversion, and Promotion Eligibility: A Qualitative Study of U.S. Servicemembers Views on Tobacco Use and Control in the Military.

More than half a century after the first Surgeon General's Report on Smoking and Tobacco Use, tobacco use remains the leading cause of preventable disease for the U.S. military. Military tobacco use impairs troop readiness, decreases productivity, reduces servicemember physical performance, and leads to chronic illness in veterans. The Department of Defense (DoD) spends considerable effort to maintain a combat ready force, and tobacco use is contradictory to these efforts. U.S. servicemember tobacco use is estimated to cost the federal government more than $6.5 billion annually. The uniqueness of military culture allows for innovative means of tobacco regulation and prevention. Our study examines the U.S. Navy cultural and servicemember perceptions to inform future tobacco control research and policies. We developed a behavioral model of tobacco use from existing literature. Using this model as a theoretical framework, our study qualitatively examined tobacco use in the active duty Navy population stationed in Okinawa, Japan. Thirty one-on-one interviews were conducted with active duty servicemembers. Sessions were recorded, transcribed, and analyzed in MAXQDA12. Multiple military-specific themes were identified. Themes: (1) tobacco use is a "right," (2) the military may limit active duty servicemembers' rights, (3) tobacco restrictions are justified if they prevent harm to others, (4) tobacco restrictions are not widely enforced, (5) smoke breaks are viewed as a legitimate reason to rest at work, and (6) the benefit of tobacco is as a stimulant. Novel tobacco cessation techniques suggested by our study include: (1) expand the buddy system to create an artificial support network for tobacco cessation and (2) tie promotion eligibility to tobacco use. This qualitative study identifies military-specific themes from the tobacco user perspective that help to guide research and policy in reducing tobacco use among military servicemembers. Possible interventions suggested by our findings may include replacing tobacco breaks with fitness breaks to relieve workplace stress and support the culture of fitness, expanding the use of pharmacologic stimulants to replace tobacco when used to maintain alertness, and gathering social support for tobacco cessation from non-healthcare unit members. Further study is needed to elucidate the effectiveness of proposed interventions suggested by our findings, with the ultimate aim of policy changes within the military to optimize health and military readiness, while decreasing long-term health effects and costs of tobacco use.

Analysis and determinants of Chinese navy personnel health status: a cross-sectional study

BackgroundThere have been very few studies analyzing the relationship of physical and mental health status with health behaviors and deployment status in Chinese navy personnel. Thus, we undertook this survey to assess this relationship and identify specific factors affecting the physical and mental health status.MethodsThe subjects enrolled in this study were selected from four units of the active-duty navy personnel in China, based on a cluster random sampling design. A total of 1200 Chinese navy personnel participated and completed the questionnaire survey that included veteran SF-36 form and a self-designed questionnaire regarding their sociodemographic characteristics, deployment status, self-rated health status and health behaviors. Totally 1200 questionnaires were distributed to different participants, while 1083 valid questionnaires were included in the final analysis. All data were analyzed using SPSS18.0 software.ResultsBased on the information provided by navy personnel, 17.82, 35.09 and 23.08% rated their health as excellent, very good and good, respectively. The mean score of physical component summary (PCS) and mental component summary (MCS) was 50.53 and 41.39, respectively. Length of service, binge drinking, regular drinking and BMI appeared to be associated with PCS score, while household income, binge drinking and BMI affected MCS score. Deployment status and smoking exhibited no significant association with PCS and MCS scores.ConclusionsOur study suggested that the sociodemographic factors like length of service and household income, along with behavioral risk factors like binge drinking, regular drinking and body mass index (BMI), seem to affect the physical and mental health status of Chinese navy personnel. However, additional data collection and more detailed analysis would still be required to develop a systematic, comprehensive and corresponding health education program to promote overall health status.

O, say does that star spangled banner yet wave

August in the Kuwait desert; I was hot, sweating profusely, and jet-lagged. And this was going to be my home for nearly a year. Even in the “air-conditioned” command tent, it was above 90 degrees. The current commanding officer was a seasoned active duty Navy Medical Corps captain. Looking calm, cool, and dry and with his legs propped up on his desk, he described for me his duties and responsibilities. I was so miserable and tired that I was having difficulty keeping my eyes open and focusing on his words. The temperature was 126 degrees Fahrenheit outside, and I was not acclimated. I had taken off the jacket of my desert cammies. My brown T-shirt was soaking wet with sweat.

Abdominal Circumference Measurements in a US Navy Active Duty Population

Abdominal Circumference Measurements in a US Navy Active Duty Population