Navy Sailors Research Articles

Frauds on Navy Pay and the Men and Women of Maritime London, c.1620–1740

Abstract During the wars of the seventeenth and early eighteenth centuries tens of thousands of English sailors had their wages deferred because the government could not come up with the cash to pay them. Instead, Navy sailors were discharged with undated government promissory notes, usually called ‘sailors’ tickets’, which they and their families sometimes had to wait months or years to have paid. This essay traces the way the Navy tried to institutionalize this system, and it also looks at competing ordering projects coming from within the London maritime community that sought to pressure the government to pay the tickets in a timely fashion, to manage overextended credit networks and — in the face of considerable Navy opposition — to make tickets more fungible so they could be used as collateral for debts. One feature of these conflicts was the rise of frauds on sailors’ pay tickets, and over time the Navy endorsed increasingly punitive methods to deal with the problem, most notably various kinds of institutional prosecution. The people indicted for ticket fraud, many of them at the Old Bailey, were predominantly women, and their ‘crimes’ were linked to more legitimate activities long associated with sailors’ female relatives. This essay argues that predatory borrowing by the State and the competing ordering projects to which it gave rise helped to configure as well as to distort social relations and economic opportunity both for women and men within the maritime community.

Differences in Musculoskeletal Injury and Disability Rates in U.S. Navy Sailors Aboard Aircraft Carrier and Amphibious Assault Ships.

Musculoskeletal injuries (MSKI) are the most common clinical condition in the military that affect medical readiness. Evaluation of MSKI burden and the effects of these injuries on readiness in large deck Navy ships is warranted. A retrospective cohort study assessing population-level MSKI rates, short-term disability (restricted duty), and long-term disability episode counts of all Sailors assigned to U.S. Navy Aircraft Carriers (CVNs) and Amphibious Assault Ships (LHA/LHD) from November 2016 to February 2023 was extracted from the Musculoskeletal Naval Epidemiological Surveillance Tool. A negative binomial regression and general additive (Gaussian) models evaluate the association of ship platform, deployment status, days underway, and sex with MSKI rates and the proportion of cases that resulted in short-term disability, returned-to-duty following restricted duty, or progressed to long-term disability. Sailors attached to CVNs contributed a mean 17,893.8 ± 23,280.6 person-months, with those attached to LHA/LHDs contributing an average 5,981.8 ± 8,432.7 person-months. Aboard CVNs, MSKI occurred at a rate of 0.30 ± 0.16/1,000 person-months while deployed and 0.64 ± 0.31/1,000 person-months in homeport. Aboard LHA/LHDs, Sailors incurred MSKI at a rate of 0.59 ± 0.58/1,000 person-months while on deployment and 1.24 ± 0.68/1,000 person-months in homeport. Among Sailors aboard CVNs, short-term disability occurred in 7.95 ± 7.75% of MSKI cases while deployed and 5.13 ± 5.26% while in homeport. Aboard LHA/LHDs, 8.57 ± 13.42% of MSKI cases were placed on short-term disability while deployed and 4.95 ± 5.27% while in homeport. In the multivariable assessment of short-term disability, being deployed underway was a significant factor (B = 3.62 P = .03, variance explained = 3.86%). Sailors that were female and served aboard LHA/LHDs returned to full duty at a significantly greater frequency compared to their male counterparts and Sailors serving aboard CVNs. None of the independent variables evaluated were associated with long-term disability. The findings in the current study demonstrate the substantial burden of MSKI aboard large deck ships, both in homeport and while deployed. Inclusion of a physical therapist aboard LHA/LHDs, like the CVN, may help to prevent and mitigate the effects of MSKI through early access to specialized care and integral injury prevention and performance optimization methods.

Risks for Enlisted Navy Divers Compared to Other Enlisted Sailors: An Examination of Illnesses That May Be Associated With Exposure to Contaminated Water Diving.

Illnesses among Navy divers degrade readiness, decrease manpower levels, and increase costs for medical care. Prior research has shown that Navy divers have high rates of the types of illnesses that might be because of diving in contaminated water. The objectives of this study were to examine medical records of U.S. Navy Sailors from 2016 to 2022 and determine if divers have higher incidence rates of health conditions that might be associated with contaminated water diving compared to non-divers. For this retrospective cohort study, we used data from the Defense Medical Epidemiology Database (DMED). The DMED is operated by the Armed Forces Health Surveillance Division and uses data from the Defense Manpower Data Center to classify occupations. The DMED provides free online access to a de-identified subset of data contained within the Defense Medical Surveillance System.The population was U.S. Navy enlisted males, aged 25 to 29 years. Divers were compared to non-divers using 8 selected diagnoses that may reasonably be associated with diving in contaminated water. During the study period, the database contained a total of 5,474 diver and 827,406 non-diver person-years. Of the 8 diagnoses, the ones with the largest number of cases for divers were upper respiratory infections with 128 and ear disorders with 62. The relative risks (RRs) for divers compared to non-divers were higher for otitis externa (RR = 1.44; confidence interval = 1.03, 2.01) and for ear disorders (RR = 1.15; confidence interval = 0.89, 1.47); for the other 6 diagnoses, the divers had lower rates than the non-divers. The high RRs found for otitis externa and ear disorders support the need to devote resources to better understand the reasons for these higher risks and to develop, test, and implement targeted risk-reduction strategies. Future studies should attempt to link verified contaminated water exposures with adverse health outcomes and calculate risks based on criteria such as age and dive factors.

Hey Siri! does he love me? Unveiling the phenomena of emotional detachmentamong seafarers

Purpose The challenges seafarers face are unique due to the nature of their work. Individuals in this profession face unique stressors such as limited interaction with people, isolation from society, confined workspaces, unpredictable weather conditions and exposure to hazardous situations. Quantitative methods used in studies on seafarers’ well-being fail to capture the individual experiences, emotions and motivations that make up their rich tapestry. The prevailing reliance on close-ended questionnaires is a hindrance to seafarers’ expression of subjective experiences and difficulties. It is essential to prioritize their well-being, both from a humanitarian standpoint and an economic perspective. Design/methodology/approach For this study, the authors coted qualitative data using open-ended semi-structured questionnaires from 35 (35) merchant navy sailors. The drive of the study was clearly stated to the respondents by the researchers. The study focuses on the emotional detachment of seafarers and follows a two-phase sampling process: criterion sampling and snowball sampling. The sampling methods are chosen in accordance with the purpose of the study. Findings The in-depth qualitative inquiry and detailed analysis of interview excerpts generated three broad themes that explain the occurrence of emotional detachment among seafarers. The qualitative study advances the knowledge base of the intricate phenomena of mariner’s emotional detachment. The themes illuminate the causes and outcomes of emotional detachment, also necessitating the need for intervention. Originality/value This study highlights the issue of seafarers at work, which tends to affect their personal and professional lives. The lived experiences of seafarers help us understand the issue of emotional detachment from a better and more in-depth perspective. This certainly helps companies and policymakers customize their interventions to seafarers’ needs.

US Navy Sailors Modify Their Eating Behaviors to Pass Cyclic Physical Readiness Tests

ObjectiveInvestigate the influence of physical readiness tests (PRTs) on eating behaviors among US Navy Sailors. DesignFocused ethnography using interviews and military policies. SettingThree US Naval installations. ParticipantsActive-duty enlisted Sailors (n = 32). Phenomenon of InterestEating behaviors. AnalysisAuthors analyzed data iteratively with data collection using domain, taxonomy, and thematic analysis to identify culturally relevant codes, domains, and themes. ResultsFive themes corresponded with PRT timing and Sailors’ perceived ability to meet standards: (1) maintain usual eating habits, (2) get ready and switch it up, (3) make weight—damage control, (4) return to baseline—PRT is over, and (5) eat whatever—PRT is canceled. In contrast to the PRT policy's goal for Sailors to maintain standards and a healthy lifestyle, many Sailors modified their usual eating behaviors to pass the test. Conclusion and ImplicationsChanges in eating behaviors during PRT cycles highlight a culture of getting ready vs staying ready, suggesting many Sailors do not eat a nutrient-dense diet to maintain the minimum physical fitness and body composition standards. There is a need for nutrition education for healthy weight maintenance, weight gain prevention, and healthy weight loss among military personnel.

An observational objective job analysis of role related tasks undertaken by Royal Navy sailors.

The current in-service Royal Naval Fitness Test has two elements to test the aerobic endurance and muscular strength of Service Personnel through generic field-based tests and a short job task simulation. However, in 2017 the Royal Navy (RN) identified a requirement to update their in-service fitness test to align with international best practice. The purpose of this study was to conduct an Objective Job Task Analysis on critical, physically demanding tasks that could be undertaken by RN sailors during sea deployments. Twenty-one training exercises were observed across a range of contexts; Type 23 Frigates, Type 45 Destroyers and at shore-based training facilities. A total of 203 RN personnel (age 27.8±7.1 years) were observed undertaking 36 job related tasks (e.g., 'firefighting', 'damage control', 'abandon ship' and 'casualty handling'). Tasks were evaluated by cardiovascular response, primary functional movements and contextual factors to aid a Military Judgement Panel in task list down-selection. 14 Criterion Tasks (e.g., 'firefighting', 'two-person magazine stowage' and 'casualty handling') were selected to progress to the next stage of the process. Five tasks were selected based on cardiovascular responses and a further nine tasks selected based on task ergonomics and other factors. This research has identified and quantified the most physically demanding, critical roles undertaken by RN sailors on sea deployments and will inform the development of the RN Physical Employment Standard.

Sleepy and grumpy go hand in hand for US Navy Sailors.

The study explores how sleep, sleep-related practices, and behaviors, in addition to various demographic and occupational characteristics, are related to overall mood of US Navy sailors when they are underway. Longitudinal assessment of US Navy sailors performing their underway duties (N = 873, 79.2% males, median age 25 years). Participants completed standardized questionnaires, wore wrist-worn actigraphs, and completed daily activity logs. Sailors who reported worse profile of mood states (POMS) total mood disturbance scores had shorter sleep duration, worse sleep quality, and more episodes of split sleep. The group with worse mood also reported more symptoms of excessive daytime sleepiness as well as more symptoms of insomnia. In addition to sleep results, sailors with worse mood also tended to be younger, more likely to use nicotine and tobacco products, and less likely to have an exercise routine when compared to sailors with better POMS scores. Finally, the group with worse POMS scores included more enlisted personnel, tended to work more hours per day, and were more likely to stand watch-especially on rotating watch schedules. The results found significant associations between the sleep practices and mood of sailors aboard US Navy ships. Numerous other demographic and occupational factors were also strongly associated with mood. This paper is part of the Sleep and Circadian Rhythms: Management of Fatigue in Occupational Settings Collection.

The health of Royal Navy sailors in the West Indies during the American War of Independence, 1776–1783

The islands of the West Indies are often considered the most dangerous places for eighteenth century British sailors. Contemporary sources maintain that the level of sickness and mortality in the West Indies crippled the Royal Navy's fleet to such an extent as to render it extremely ineffective during the American Revolutionary War. There can be no doubt that disease, accidents and naval action had an effect on the Royal Navy in the West Indies; however the true extent of the impairment has been grossly exaggerated. This paper seeks to examine the precise effects of disease and mortality on British sailors stationed in the West Indies during the American War of Independence.

Predicting Skilled Workforce Retention: A Machine Learning Approach with Royal Australian Navy Sailors

Predicting Skilled Workforce Retention: A Machine Learning Approach with Royal Australian Navy Sailors

0171 Assessment of Student Sleep and Well-Being During a Stress Inoculation Training at The U.S. Navy Surface Warfare Officers School

Abstract Introduction Military operations frequently take place in complex, volatile, and ambiguous environments, where important information may be uncertain. These circumstances are often highly stressful, and fatiguing due to sustained operations, shift work, sleep loss, and the taxing nature of the work. As a crucial part of their preparation for leading U.S. Navy sailors, prospective executive officers (PXOs) in the Surface Warfare community receive training at the Surface Warfare Schools Command (SWSC). At the request of SWSC, the NPS research team was asked to assess the stress loads of SWO students during their expanded 10-week training course, which included the implementation of a stress inoculation training (SIT) program. Methods SWOs (N=50) attending the Prospective Executive Officer (PXO) Course at SWSC participated in a quasi-experimental longitudinal study. They completed questionnaires three times during the PXO course: at the beginning of the study, at the mid-point, and at the end of the course. Standardized tools were used to assess perceived stress levels (Perceived Stress Scale – PSS), depression symptoms (Patient Health Questionnaire – PHQ-8), anxiety (General Anxiety Disorder questionnaire – GAD-7), and mood (Profile of Mood States – POMS). Sleep attributes were assessed by wearable devices (ŌURA rings). Results Overall, the scores of SWOs on the PSS, PHQ-8, GAD-7, and POMS were lower or equivalent to scores reported for the general population. However, reported levels of perceived stress increased significantly from the beginning to the end of the PXO course (average PSS=9 vs 12). However, PHQ-8, GAD-7, and POMS scores remained stable across the three time points. On average, PXOs received 6.6 ± 0.65 hours of sleep per night on weeknights at SWSC, with about one additional hour of sleep on weekends. Conclusion These findings indicate that, while SWOs experienced an increase in perceived stress during the PXO course, their overall well-being is not substantively different from the general population. Participants appear to use weekends for additional restorative sleep, obtaining adequate amounts of sleep on weekends. We did not observe evidence of impairments in mental or physical wellness of SWOs attending the PXO course at SWSC. Support (if any)

0167 Influence of light exposure, exercise, caffeine intake, and nicotine use on sleep of U.S. Navy sailors during home port operations

Abstract Introduction Insufficient sleep is pervasive in U.S. Navy (USN) sailors and has been associated with increased risk of injury and mood disturbances. As such, monitoring sleep and identifying modifiable targets that influence sleep in this population is essential. We examined the sleep of USN sailors during 9-months in port and explored the influence of different lifestyle behaviors on sleep. Methods Sailors (n = 101, 31 ± 7 years old [mean ± SD], 21% female) wore a commercial wearable sleep-tracking device (Oura Ring, Gen2) during a 9-month home port maintenance period (September 2021 – May 2022). During the study, the sailors slept at home and had periods working on the ship (on-hull; higher demands) and off the ship (off-hull; lower demands). Participants also completed 5 self-report surveys that assessed sleep quality (Pittsburgh Sleep Quality Index; PSQI) and multiple lifestyle behaviors including: hours of natural light exposure, hours of moderate/vigorous physical activity, and intake of caffeine, nicotine, and alcohol. Sleep outcome measures from the wearable device included total sleep time (TST), standard deviation of TST (SD TST), and sleep efficiency (SE). Linear mixed models were used to examine the effects of lifestyle behaviors on sleep. Timepoint and on/off-hull condition were also included as fixed effects, while participant was included as a random effect. Results Participants slept 6.5 ± 0.7 hours a night (6.2 ± 0.9 on-hull; 6.4 ± 0.8 off-hull; p > .05) and had slightly elevated PSQI scores that were higher on-hull (8.3 ± 4.6) than off-hull (6.5 ± 3.5; B = 1.83, Std. Error = 0.71, p = .01). Lifestyle behaviors were not significant predictors of PSQI, TST, SD TST, or SE (p > .05). Conclusion Lifestyle behaviors had weak relationships with self-reported and objective sleep outcomes in this exploratory analysis. Therefore, modifying lifestyle behaviors may not significantly influence sleep in USN sailors during home port periods. Still, additional behavioral targets (e.g., diet), specific aspects of behavioral outcomes (e.g., light exposure timing, exercise intensity), and other work-related factors (e.g., workload, schedule) that can affect sleep should be explored in future efforts. Support (if any) Military Operational Medicine Research Program (work unit no. N2010).

Navy Sailors Health Behavior: A Multi-Factor Analysis of Circadian Rhythm on Naval Operational Capability

Objective: The objective of this research was to determine the impact of circadian rhythm disorders on sleep disorders, fatigue and health problems of navy sailors from the perspective of their health behavior. During its voyage, navy crews have obvious problems such as sleep disorders and fatigue, among which the circadian rhythm disorder was the most common. Warning system, special environment at sea, pressure and other factors can lead to the occurrence of circadian rhythm disorders. Methods: The primary data was used in this research with a sample size of 278 and Smart PLS was used for statistical analysis. Results: According to empirical data, the impact of circadian rhythm disorders was significant on sleep disorders, fatigue and health problems of navy sailors. The research is novel in the literature because very few studies have discussed the circadian rhythm disorders in the context of navy sailors. Conclusion: The research implications in the theory are reliable to enhance the body of knowledge of circadian in the significant way. Furthermore, the study has some practical implications to work on to enhance the practices to improve the health of navy sailors during their long time in the sea.

Caffeine consumption and sleep in a submarine environment: An observational study.

Submariners face many environmental and operational challenges to maintaining good sleep, including suboptimal lighting, shift work, and frequent interruptions. Anecdotally, many Sailors consume caffeine to alleviate the effects of poor sleep on alertness, mood, and performance; however, caffeine itself may also degrade sleep quantity and/or quality. This study provides the first exploration of the potential relationship between caffeine use and sleep onboard submarines. Objective measures (wrist actigraphy, available from 45 participants), self-report sleep metrics, and self-reported caffeine consumption were collected from 58 US Navy Sailors before and during a routine submarine underway at sea lasting 30 days. Contrary to expectations, less caffeine was reportedly consumed at sea (232.8 ± 241.1 mg) than on land prior to the underway (M = 284.4 ± 251.7 mg; X2 (1) = 7.43, p = 0.006), positive rather than negative relationships were observed between caffeine consumption and sleep efficiency (F = 6.11, p = 0.02), and negative relationships were observed between caffeine consumption and wake after sleep onset (F = 9.36, p = 0.004) and sleep fragmentation (F = 24.73, p < 0.0001). However, in contrast, higher caffeine consumption was also negatively related to self-reported sleep duration while at sea (F = 4.73, p = 0.03). This observational study is the first to measure relationships between caffeine consumption and sleep quantity and/or quality in a submarine environment. We propose that the unique submarine environment and the unique caffeine consumption patterns of submariners should be considered in the development of potential countermeasures for sleepiness.

William Falconer's “Sons of Neptune”: The Merchant Service, the Royal Navy, and The Shipwreck

One month after the publication of his poem on merchant seafaring, The Shipwreck (1762), William Falconer left merchant sailing to become a junior officer in the Royal Navy. In the midcentury, many commentators believed that the Royal Navy's sailors were superior to merchant sailors. Falconer's response can be traced by contrasting his first edition of The Shipwreck with the revisions he made to the poem after joining the Royal Navy. The revisions address directly the notion that merchant sailors value only financial reward, but then focus on the notion that sailors who fight for king and country are braver than those who move cargo. In the revised narrative of the sailors’ battle with the elements, Falconer emphasizes the physical limits to their bravery, and thus suggests that merchant sailors are like Royal Navy sailors because all sailors are equally vulnerable to storms at sea.

Dispositional resilience predicts psychological adaptation of seafarers during and after maritime operations.

Seafarers, whether on cargo, fishery, or naval ships, may be exposed to unique and unusual psychological demands related to the often isolated, confined, and extreme environments associated with ocean-going vessels. This necessitates optimal psychological adaptation to maintain individual well-being during the mission and afterwards. This study set out to explore whether psychometric measures could predict psychological adaptation of seafarers, specifically navy sailors, during and after maritime operations. It used emotional regulation as marker of adaptation, and examined the role of psychometric measures of dispositional resilience and emotional regulation to predict psychological adaptation at subsequent time-points. A total of 168 sailors completed the Brief Sailor Resiliency Scale, Dispositional Resilience Scale 15, and Mental Toughness Questionnaire 18 prior to departing for sea, as well as the Brunel Mood Scale at 5 time points over a 12-month operational cycle. Higher resilience scores were consistently associated with more adaptive emotional regulation. Multiple linear regressions indicated that the Brief Sailor Resiliency Scale predicted emotional regulation over the shorter term, while the Mental Toughness Questionnaire 18 predicted emotional regulation over the longer term. Further, mid-mission emotional regulation also predicted emotional regulation at the end of deployments. The findings support several practical applications. Firstly, formal organizational initiatives to promote resilience could be useful to enhance adaptation during and after missions. Secondly, measuring seafarers' dispositional resilience could allow the streaming of vulnerable individuals towards appropriate mental health support services. Thirdly, past indicators of adaptation could be useful to enhance decision- making regarding subsequent utilisation. This may be applicable to seafarers in both naval services and commercial shipping, and to personnel in remote weather stations or other isolated and inaccessible research facilities.

Antibody Responses to the SARS-CoV-2 Ancestral Strain and Omicron Variants in Moderna mRNA-1273 Vaccinated Active-Duty US Navy Sailors and Marines.

Omicron and its subvariants have steadily gained greater capability of immune escape compared to other variants of concern, resulting in an increased incidence of reinfections even among vaccinated individuals. We evaluated the antibody response to Omicron BA.1, BA.2, and BA.4/5 in US military members vaccinated with the primary 2-dose series of Moderna mRNA-1273 in a cross-sectional study. While nearly all vaccinated participants had sustained spike (S) IgG and neutralizing antibodies (ND50) to the ancestral strain, only 7.7% participants had detectable ND50 to Omicron BA.1 at 8 months postvaccination. The neutralizing antibody response to BA.2 and BA.5 was similarly reduced. The reduced antibody neutralization of Omicron correlated with the decreased antibody binding to the receptor-binding domain. The participants' seropositivity to the nuclear protein positively correlated with ND50. Our data emphasizes the need for continuous vigilance in monitoring for emerging variants and the need to identify potential alternative targets for vaccine design.

Henry Breault: Construction of a naval hero

United States Navy sailors are excellent subjects for personal microhistories due to the volume of surviving official documentation in the form of their Official Military Personnel Files. This article deconstructs a grand narrative surrounding Henry Breault, the only enlisted sailor to receive his Medal of Honor while serving aboard a submarine. Breault experienced contemporary enshrinement, a long period of sporadic interest, and a later iconographic construction into a submarine folk hero in the present day. Breault has come to represent unnamed submariners, who are expected to perform in the same fashion with no expectation of similar commendation. It is found that Breault is still representative of sailors, but as an ordinary man who acted in an extraordinary manner when circumstance required. The methodology provides insight into Breault's relationship and connection to greater society as a submariner and as a highly decorated sailor in the interwar period.

Pre-deployment Vitamin D And Nutritional Status In Us Navy Sailors

PURPOSE: Navy shipboard personnel have difficulty meeting dietary needs due to limited food options resulting from military operations in isolated environments with infrequent resupply opportunities. The impact of such dietary deficiencies on health and operational readiness is not well characterized. The purpose is to document operational nutrition capability gap(s) and benefits of using a fleet-based dietitian. METHODS: U.S. Navy Sailors (41 males; 30 females, age = 18-45) were assessed pre-deployment for height (m), weight (kg), body mass index (BMI, kg/m2), body fat (BF%), blood pressure (BP, mmHg), and nutritional biomarkers (lipid panel, HemoglobinA1C (HgA1c), ferritin (FE), C-reactive protein (CRP), Comprehensive Metabolic Panel (CMP), and Complete Blood Count (CBC)) via non-fasted venipuncture. Diet, lifestyle, and occupational habits were evaluated using validated questionnaires. Pre-deployment only data is presented and summarized using means±SE. RESULTS: Most Sailors (80%) had low (<20 ng/ml; n = 18) to suboptimal (20 to <30 ng/ml; n = 43) Vitamin D3 (D3) levels. Total cholesterol levels were borderline (170-199 mg/dl; n = 27) in 42% and high (>200 mg/dl; n = 11) in 16% of Sailors. Most (73%) had normal triglyceride levels (<150 mg/dl; n = 52) with five at levels >200 mg/dl. High BP (mean = 129/79) was detected in 57% of Sailors (i.e., systolic>130 or diastolic>80 mmHg). HgA1C levels (5.1 ± 0.1%) were normal, but inflammation was detected in five Sailors (CRP > 1 mg/dL), and two also had elevated FE levels (>300 mg/dL). Twelve males had high FE levels with normal CRP indicative of iron overload (range = 297 to 752 mg/dl). Additionally, 13% of females had a negative iron balance (FE < 20 mg/dL). Over a third of females (40%; BF% = 32.7 ± 1.2%) and one third of males (33%; BF% = 23.0 ± 0.9%) fell outside Navy standards. Pittsburgh Sleep Quality Index Global scores (7.3 ± 0.4) were consistent with poor sleep quality (score > 5) in most Sailors (58%). CONCLUSIONS: Sailors had key deficiencies in nutrition, sleep, and general health. Pre-deployment D3, a vitamin important for bone and immune health, were low to suboptimal in 80% of the Sailors with a further decline expected during deployment if left untreated. A screen-to-treat protocol for D3 may be warranted.

0165 Prevalence of insomnia and/or obstructive sleep apnea in a sample of fit-for-duty U.S. Navy sailors

Abstract Introduction Obstructive sleep apnea (OSA) and insomnia are prevalent sleep disorders, known to negatively impact sleep and well-being in civilian populations. Studies of these sleep disorders in military populations have focused on individuals seeking treatment for a sleep disorder, rather than the general active-duty service member (ADSM). In this study, we investigated the prevalence of OSA and insomnia in U.S. Navy sailors serving on surface ships. Methods We analyzed pre-collected data from 548 fit-for-duty sailors (MD age=25 years, IQR=9; 79.4% males) serving on nine US Navy surface ships. Sailors reported their demographic information, health-related habits, and whether they had been diagnosed with OSA and/or insomnia. Sleep was assessed with wrist-worn actigraphy (371 sailors). Results Approximately 66.8% of sailors reported having an exercise routine, 83.6% reported drinking caffeinated beverages, and 29.1% used nicotine products. In terms of disorders, 15 (2.7%) male sailors reported having been diagnosed with OSA, 12 (2.2%) with insomnia (8 males, 4 females), and one (0.2%) male sailor with comorbid insomnia and OSA. Compared to sailors without a sleep disorder, sailors with OSA were older (MD=34 years, IQR=7; p&amp;lt;0.001) and had a higher proportion of nicotine users (53.3%) (p=0.041). Sailors with insomnia did not differ from sailors with no sleep disorder in terms of demographics and habits. The average daily sleep duration was 6.4±1.0 hours, which did not differ between disorder groups. However, sailors with insomnia had more sleep episodes per day (MD=1.7; IQR=0.9) than sailors without a sleep disorder (MD=1.3, IQR=0.5; p=0.042). Conclusion Only ~5% of the sailors in our study reported a diagnosis of OSA and/or insomnia, whereas one in three people in the general population has a sleep disorder. Notably, all sailors, regardless of sleep disorder diagnosis, exhibited short sleep durations. Previous studies of ADSMs found that ~48% reported poor enough sleep quality to meet the diagnostic criteria for a sleep disorder. Thus, our results suggest that, despite evidence that many Sailors exhibited sleep problems, sleep disorders are significantly underdiagnosed in ADSMs. Support (If Any) This work was supported in part by the Naval Medical Research Center's Naval Advanced Medical Development Program (MIPR N3239820WXHN007).

Health Conditions Among Navy Submariners at the End of Active Duty; A Retrospective Cohort Study.

Maintaining healthy, well-trained, and highly qualified armed forces is critical for ensuring military readiness. The purpose of this article is to contribute to the body of research focused on the health of U.S. Navy submariners and to identify the health conditions of U.S. Navy submariners during their final year of active duty service. In this retrospective cohort study, we examined medical records and personnel files of separating U.S. Navy sailors who were: (1) active duty between 2009 and 2018; (2) separated before 2019; and (3) were assigned to a submarine for at least 30 days. Both officers and enlisted service members were included. We linked, described, and analyzed data from the Defense Health Agency, Military Health System Data Repository (MDR), and the Bureau of Naval Personnel (BUPERS). International Classification of Diseases (ICD) diagnoses codes were obtained from MDR. Data collected from BUPERS include age, sex, and rank. We determined the number of individuals who had at least one diagnosed condition (identified as a three-digit ICD code). We report the number of diagnoses and calculate prevalence rates and confidence intervals per condition, as well as prevalence rates per year, using standard formulas. The study was approved by the Naval Submarine Medical Research Laboratory Institutional Review Board. During the study period, 26,014 submariners separated from the Navy. The average number of separations per year was 2,601. About a third of the separating submariners were in the 25 to 29 age group and over 50% were under 30 years of age. Of the three-digit individual ICD codes, some of the highest operationally relevant rates over the 10-year study period (2009-2018) were for joint disorders (prevalence rate [PR] = 180 per 1,000 submariners), back disorders (PR = 128), and sleep disorders (PR = 134). Three mental-health-related conditions were also among the 20 conditions with the highest rates. High rates of specific diagnoses such as joint disorders indicate the need for additional study to examine causal relationships, to determine which conditions may contribute to lost work time, early separations, or low rates of reenlistment and which conditions might be a result of specific military occupations or duties. Study strengths are the large number of subjects and the long period of observations. A study weakness was the inability to identify submariners who separated because of health conditions. The overall impact of the study is that it identifies urgent health risks and establishes a way to prioritize future research. Future research should include a focus on medically separated personnel; compare rates for submariners to other military groups including all-Navy and all-Department of Defense; and determine specific and relative risks as a necessary precursor to developing, implementing, and testing risk reduction and health improvement interventions.