Cervical headgear therapy and sleep-related attributes.

INTRODUCTION: The study aimed to assess (1) the effect of the treatment with cervical headgear on patients' sleep-related attributes and well-being and (2) whether these sleep-related parameters (ie, sleep quality and quantity) were associated with patients' compliance during the orthodontic treatment. METHODS: The study protocol was based on a prospective longitudinal quasi-experimental design. Participants (n = 26; 9 males; mean age, 12.4 ± 1.68 years) were patients in the Postgraduate Orthodontic Clinic, National and Kapodistrian University of Athens. All patients received treatment with a cervical headgear having an embedded TheraMon microsensor. Sleep was assessed by wrist-worn actigraphy for 59 ± 19 days. The Epworth Sleepiness Scale was used to assess average daytime sleepiness, whereas we used the Athens Insomnia Scale for insomnia symptoms. Oral health-related quality of life (OHRQOL) was assessed by the Oral Health Impact Profile (OHIP-14). RESULTS: Patients slept on average 7.35 ± 0.42 h/d. Compared with the lowest sleep duration recommended for their age group, patients had an average chronic sleep deficit of 1.40 ± 0.49 h/d. Patients wore the headgear 90.9% of the days for 10.40 ± 4.17 h/d. However, only 7 (28%) patients reached or exceeded the wear-time recommendation of 12 h/d. In contrast, 2 (8%) patients wore headgear <5 h/d, 11 (44%) 5-10 h/d, and 12 (48%) patients wore headgear >10 h/d. Aggregated by participants, the median Epworth Sleepiness Scale score during the study was 3.40 (interquartile range [IQR], 4.85; range, 0.2-13.6), the median Athens Insomnia Scale score was 3.00 (IQR, 4.25; range, 0-7), and the median Oral Health Impact Profile score was 1.40 (IQR, 4.17; range, 0.0-20.8). Compared with patients who wore the orthodontic appliance >7.8 h/d, patients who wore it <7.8 h/d had worse average daytime sleepiness (P = 0.050) and worse OHRQOL (P = 0.019). CONCLUSIONS: Orthodontic treatment with cervical headgear has no substantive negative effect on sleep attributes (quantity and quality), average daytime sleepiness and OHRQOL. However, poor compliance with orthodontic treatment seems to be associated with higher levels of daytime sleepiness.

Small Boat Recovery Task Performance in a Moving Environment.

OBJECTIVE: Assess operator performance in a simulation of US Coast Guard small boat recovery to a larger vessel on a large scale, six degree-of-freedom, full motion simulator. BACKGROUND: Studies of human performance in small boat recovery task have never been conducted on a high amplitude, low frequency simulator. Empirical evidence of small boat recovery task performance in challenging motion conditions is needed to inform future maritime systems designs. METHOD: Experienced active-duty boat crewmembers (N = 13) conducted a small boat recovery task in three sea states on the Vertical Motion Simulator (VMS) at the NASA Ames Research Center. Task performance was assessed using a task equivalent for time to complete the task. Participant behaviors associated with increasing motion severity were observed. RESULTS: Task performance declined as motion conditions became more severe. Participants were more likely to use at least one hand to maintain balance during motion conditions, becoming more frequent with increasing motion severity. Many participants used one hand to complete the task despite contrary instructions and previous experience. CONCLUSION: Two design recommendations were proposed to counter declining task performance in increasingly severe motion conditions. Handholds available to participants during the task, and task design supporting single handed completion were recommended for small boat recovery systems. APPLICATION: This research is directly applicable to gross motor tasks requiring simultaneous maintenance of balance in a maritime environment, and may be extended to other environments where humans experience complex motions while completing tasks.

Habitability in Berthing Compartments and Well-Being of Sailors Working on U.S. Navy Surface Ships.

OBJECTIVE: The study had two objectives: (a) to assess the prevalence of sleep-related habitability concerns in the berthing compartments of U.S. Navy surface ships and (b) to assess whether habitability issues in berthing compartments affected the sleep and well-being of crew members. BACKGROUND: The importance of habitability for human well-being is recognized. Little is known, however, about the association between habitability factors in the sleeping/berthing compartments and sailor well-being in operational conditions. METHOD: Fit-for-duty sailors (N = 1,269; from six ships) participated in this naturalistic and longitudinal study. Sailors reported habitability factors affecting their sleep and completed four standardized questionnaires to assess daytime sleepiness, insomnia, sleep quality, and mood. Sleep was assessed through wrist-worn actigraphy and activity logs. RESULTS: Noise, ambient temperature, poor bedding conditions, and ambient light were the most frequently reported factors of concern. Compared to their peers with fewer complaints, sailors with more habitability-related complaints were more likely to have elevated daytime sleepiness (by 23%) and to report insomnia symptoms (145%) and lower sleep quality (21%). Sailors who reported more habitability-related issues also tended to sleep longer. Individuals with more complaints about habitability also tended to report worse mood (total mood disturbance, tension/anxiety, depression, fatigue, and confusion/bewilderment). CONCLUSION: Habitability-related complaints are associated with sailor well-being and sleep. Future studies should expound on the various detrimental factors that degrade conditions in berthing compartments and negatively impact crew well-being. APPLICATION: Habitability in berthing compartments of surface ships is associated with sailors' daytime sleepiness, insomnia severity, mood, and sleep attributes. Ship designers should take these findings into consideration and investigate viable and cost-effective methods to mitigate the problems we identified.

Eating behaviors in sailors of the United States Navy: Meal-to-sleep intervals.

BACKGROUND: Due to their long workdays and erratic watch schedules, sailors on United States Navy (USN) ships often eat meals close to their bedtime, which may contribute to sleep disruption. AIM: To assess the duration of meal-to-sleep (M-S) intervals in relation to timing of sailor workdays and watch schedules. METHODS: Longitudinal field assessment of USN sailors performing their underway duties (N = 234). Participants completed questionnaires, wore actigraphs, and completed activity logs. RESULTS: Approximately 35% of M-S intervals were <3 h in duration. M-S interval duration was associated with watchstanding status (p < 0.001) and the number of sections in the watchstanding schedule (p < 0.001). Sailors on the two-section watch schedule had, on average, the shortest M-S intervals (55 min) compared to sailors on three- or four-section watchbills (∼4 h) and to non-watchstanders (4.85 h). CONCLUSION: Sailors on two-section watchbills often eat quite close to bedtime. To provide appropriate recommendations regarding healthy dietary patterns, we will continue assessing dietary behaviors and food choices of sailors while underway, especially as they relate to sailor work hours, circadian rhythms, and sleep practices.

Residual excessive daytime sleepiness in patients with obstructive sleep apnea treated with positive airway pressure therapy.

PURPOSE: Patients with obstructive sleep apnea (OSA) commonly report residual excessive daytime sleepiness (EDS) despite treatment with positive airway pressure (PAP). The present study aimed to determine whether patients presenting with subjective sleepiness after treatment with PAP therapy had objective evidence of residual sleepiness. METHODS: We conducted a retrospective analysis of 29 adults with OSA on PAP therapy who underwent a standardized evaluation for EDS. Patients were evaluated with the Epworth Sleepiness Scale (ESS) and attend an in-lab polysomnogram (PSG) with PAP followed by a multiple sleep latency test (MSLT). RESULTS: Our cohort consisted of 23 men (79%) and 6 women (21%) with a mean age of 40.7 years. All patients were subjectively sleepy with an ESS score of > 10 and met minimal PAP usage of 4 h a night for at least 70% of nights with a residual apnea-hypopnea index (AHI) ≤ 10. On MSLT, 31% of patients had an average sleep onset latency (SOL) < 8 min, 35% had a SOL between 8 and 11 min, and 35% had SOL > 11 min. CONCLUSION: After optimizing PAP therapy and sleep in patients with OSA and residual EDS, the majority were found to have objective findings of an abnormally short SOL on MSLT. This is further evidence that there is a distinct OSA phenotype that will have persistent EDS despite appropriate treatment of their sleep-disordered breathing. Objective testing to quantify the degree of sleepiness is recommended for OSA patients with residual EDS.

Sleep-Related Practices, Behaviors, and Sleep-Related Difficulties in Deployed Active-Duty Service Members Performing Security Duties.

Objective: To assess sleep-related difficulties (e.g., trouble staying asleep, oversleeping, falling asleep while on duty, disturbing dreams, sleep paralysis) and behavioral patterns of active-duty service members (ADSMs) performing security duties. Participants: The participants were 1,169 ADSMs (20-44 years of age). Methods: ADSMs completed an online survey (67.3% response rate) with items assessing demographics, the occupational environment, sleep-related attributes, habits, or difficulties, factors affecting sleep, aids and techniques used to improve sleep, and the use of sleep-related products. Results: ADSMs reported sleeping ~6.5 hr/day (~56% reported sleeping < 6 hr). Sleep-related difficulties were reported by ~72% of the ADSMs (i.e., 55.1% had problems staying asleep, 33.1% reported experiencing sleep paralysis, 25.6% reported oversleeping, 21.6% had disturbing dreams, and 4.79% reported falling asleep while on duty). Daily sleep duration and quality, occupational factors (shift work, operational commitments, collateral duties, habitability, taking antimalarial medication, years deployed), and personal factors or behaviors (history of sleep problems, problems in personal life, late exercise times, altering sleep schedule to talk or text with family or friends) were associated with sleep-related difficulties. Some ADSMs reported using alcohol (~14%) or exercising prior to bedtime (~34%) in an attempt to fall sleep faster. Conclusions: We identified a high prevalence of sleep-related difficulties in our military sample. Even though most ADSMs used sleep hygiene practices to improve their sleep, some ADSMs used methods not recommended. Improving ADSMs' daily schedule (to include periods for exercising, and protected sleep periods), and further emphasis on sleep hygiene practices may be viable methods to reinforce behaviors promoting healthy sleep and improve performance.

Discriminating Between Fatigue and Sleepiness in the Naval Operational Environment.

OBJECTIVE: To assess the similarities and differences between reported levels of fatigue and sleepiness as a consequence of working at sea. PARTICIPANTS: 767 crewmembers of a U.S. Navy ship. METHODS: Retrospective analysis of a survey to include questions about demographics, caffeine consumption, sleep adequacy, the Epworth Sleepiness Scale (ESS), and the Fatigue Severity Scale (FSS). RESULTS: ESS scores (8.41 ± 4.66) indicated that 32% of the participants had excessive daytime sleepiness (ESS score > 10), while approximately 7% had an ESS score of 16 or more. FSS scores (average FSS = 3.01 ± 1.37) indicated that 28% of the participants had elevated fatigue (FSS score ≥ 4). Even though ESS and FSS scores were correlated (r = 0.39), their association explained only 15% of the variability observed. In terms of behavioral and lifestyle patterns, crewmembers with elevated fatigue (FSS ≥ 4) reported getting less exercise than those reporting less fatigue. Individuals with excessive sleepiness (ESS > 10) reported higher caffeine consumption. Crewmembers with elevated fatigue and comorbid sleepiness (FSS ≥ 4 and ESS > 10) reported receiving less sleep than other crew members. CONCLUSIONS: These results suggest that subjective fatigue and subjective sleepiness, as measured by the FSS and ESS scales, are distinct constructs and both are consequences of working at sea. The scores on the two scales correlate differentially with behavioral and lifestyle patterns of the crewmembers.

Preliminary validation study of the 3-min wrist-worn psychomotor vigilance test.

The 10-min psychomotor vigilance test (PVT) is a widely used tool to assess behavioral alertness. In operational environments, however, the 3-min version of the PVT is more practicable. Under controlled laboratory conditions, we compared performance on the 3-min PVT on a wrist-worn device with the 3-min PVT on a laptop computer. We conducted two repeated measures experiments (72 participants) to assess the effects of PVT device type (laptop or wrist-worn), backlight on the wrist-worn device (on or off), ambient light (low or normal levels), and interstimulus interval (ISI). First, we compared the wrist-worn PVT (ISI of 2-10 s) with the laptop-based PVT (ISI of 1-4 s). Participants performed six PVT trials counterbalanced for order of ambient light and device type. In both ambient-lighting conditions, the median differences in PVT metrics (reaction time, response speed, and percentage of 355-ms or 500-ms lapses combined with false starts) between the laptop and the wrist-worn PVT with the backlight on were less than 4.5 %. Specifically, the median difference in reaction times was less than 10 ms. However, the standard deviation in most metrics using the wrist-worn PVT was twice that of the laptop. In a second experiment, we compared the wrist-worn and laptop PVTs with the same ISIs (1-4 s) in normal light conditions. The results suggest that PVT data can be collected reliably in the field using the wrist-worn device with the backlight on and an ISI of 2-10 s.

Operational assessment of the 5-h on/10-h off watchstanding schedule on a US Navy ship: sleep patterns, mood and psychomotor vigilance performance of crewmembers in the nuclear reactor department.

We assessed sleep patterns, psychomotor vigilance performance, work demands and mood of 77 crewmembers of USS NIMITZ (CVN-68) on the rotating 5-h on/10-h off (5/10) watchstanding schedule. Within the 3-day cycle of the 5/10, sleep occurred at distinctly different times each day. On two of these days, sailors typically received only brief, 4-h sleep episodes followed by periods of sustained wakefulness (approximately 22 and 20 h). Crewmembers received approximately seven hours of sleep daily, but reported excessive fatigue and dissatisfaction with their schedule. Crewmembers' mood worsened significantly over the course of the underway phase. Psychomotor vigilance performance (reaction times, lapses) was significantly degraded compared to performance when working circadian-aligned schedules. Overall, standing watch on the 5/10 schedule, combined with other work duties, resulted in poor sleep hygiene. Crewmembers on the 5/10 experienced periodic bouts of sustained wakefulness and accrued a significant sleep debt due to extended workdays and circadian-misaligned sleep. Practitioner summary: We assessed crewmembers' sleep patterns, psychomotor vigilance performance and work demands when working a rotating 5-h on/10-h off (5/10) watchstanding schedule. The 5/10, combined with other work duties, resulted in poor sleep hygiene. Crewmembers experienced periodic bouts of sustained wakefulness and accrued a significant sleep debt due to extended workdays and circadian-misaligned sleep.

Psychomotor vigilance performance predicted by Epworth Sleepiness Scale scores in an operational setting with the United States Navy.

It is critical in operational environments to identify individuals who are at higher risk of psychomotor performance impairments. This study assesses the utility of the Epworth Sleepiness Scale for predicting degraded psychomotor vigilance performance in an operational environment. Active duty crewmembers of a USA Navy destroyer (N = 69, age 21-54 years) completed the Epworth Sleepiness Scale at the beginning of the data collection period. Participants wore actigraphs and completed sleep diaries for 11 days. Psychomotor vigilance tests were administered throughout the data collection period using a 3-min version of the psychomotor vigilance test on the actigraphs. Crewmembers with elevated scores on the Epworth Sleepiness Scale (i.e. Epworth Sleepiness Scale >10) had 60% slower reaction times on average, and experienced at least 60% more lapses and false starts compared with individuals with normal Epworth Sleepiness Scale scores (i.e. Epworth Sleepiness Scale ≤ 10). Epworth Sleepiness Scale scores were correlated with daily time in bed (P < 0.01), sleep (P < 0.05), mean reaction time (P < 0.001), response speed 1/reaction time (P < 0.05), slowest 10% of response speed (P < 0.001), lapses (P < 0.01), and the sum of lapses and false starts (P < 0.001). In this chronically sleep-deprived population, elevated Epworth Sleepiness Scale scores identified that subset of the population who experienced degraded psychomotor vigilance performance. We theorize that Epworth Sleepiness Scale scores are an indication of personal sleep debt that varies depending on one's individual sleep requirement. In the absence of direct performance metrics, we also advocate that the Epworth Sleepiness Scale can be used to determine the prevalence of excessive sleepiness (and thereby assess the risk of performance decrements).

IGF-1: a potential biomarker for efficacy of sleep improvement with automatic airway pressure therapy for obstructive sleep apnea?

BACKGROUND: Positive airway pressure (PAP) reverses obstructive sleep apnea (OSA)-related hypoxia and restores slow wave sleep (SWS). Insulin-like growth factor 1 (IGF-1) is a neuropeptide that facilitates the repair of neurons from hypoxia and improves sleep regulation. IGF-1 concentrations are lower in OSA, and likely increase following PAP treatment; however, this relationship has not yet been determined in a younger cohort of OSA patients. METHODS: This was a prospective, observational pilot study of 58 young men, who were diagnosed with OSA and provided PAP as an intervention. Adherence to PAP treatment over 3 months was objectively measured, as well as changes in the apnea-hypopnea index (AHI). Serum concentrations of IGF-1and C-reactive protein (CRP) were measured and correlated with PAP adherence. RESULTS: IGF-1 concentrations at baseline were similar between PAP adherent 55.5 ± 34.4 ng/ml and PAP nonadherent participants 61.2 ± 27.1 ng/ml (p = 0.4), with the overall mean IGF-1 concentration of 59.0 ± 29.9 ng/ml. At follow-up, adherent participants had concentrations of IGF-1 that were significantly higher 128 ± 59.5 ng/ml compared to nonadherent participants 86.0 ± 47.4 ng/ml (p < 0.01). Increases in IGF-1 concentrations were significantly associated with reductions in AHI (Spearman's rho = -0.409, p = 0.015). Conversely, CRP concentrations did not differ between baseline and follow-up measurements in either group. CONCLUSIONS: Adherence to PAP treatment leads to significant increases in IGF-1 concentrations in young men with OSA. While an objective measure of adherence exists, PAP usage does not allow for measure of sleep improvement. IGF-1 may serve as a potential biomarker for the efficacy of PAP therapy on improved sleep.

Yawning as a behavioral marker of mild motion sickness and sopite syndrome.

INTRODUCTION: Severe motion sickness is easily identifiable with sufferers showing obvious behavioral signs, including emesis (vomiting). Mild motion sickness and sopite syndrome lack such clear and objective behavioral markers. We postulate that yawning may have the potential to be used in operational settings as such a marker. This study assesses the utility of yawning as a behavioral marker for the identification of soporific effects by investigating the association between yawning and mild motion sickness/sopite syndrome in a controlled environment. METHODS: Using a randomized motion-counterbalanced design, we collected yawning and motion sickness data from 39 healthy individuals (34 men and 5 women, ages 27-59 yr) in static and motion conditions. Each individual participated in two 1-h sessions. Each session consisted of six 10-min blocks. Subjects performed a multitasking battery on a head mounted display while seated on the moving platform. The occurrence and severity of symptoms were assessed with the Motion Sickness Assessment Questionnaire (MSAQ). RESULTS: Yawning occurred predominantly in the motion condition. All yawners in motion (N = 5) were symptomatic. Compared to nonyawners (MSAQ indices: Total = 14.0, Sopite = 15.0), subjects who yawned in motion demonstrated increased severity of motion sickness and soporific symptoms (MSAQ indices: Total = 17.2, Sopite = 22.4), and reduced multitasking cognitive performance (Composite score: nonyawners = 1348; yawners = 1145). DISCUSSION: These results provide evidence that yawning may be a viable behavioral marker to recognize the onset of soporific effects and their concomitant reduction in cognitive performance.

Sopite syndrome: a revised definition.

In 1976, Graybiel and Knepton proposed the term "sopite syndrome" to describe a symptom complex centering on drowsiness and lethargy related to motion sickness. However, existing descriptions and definitions of sopite syndrome have limitations in fully conveying the appropriate information to the reader. Our objective is to propose a revised definition providing a more adequate conceptual framework for research. The proposed definition of sopite syndrome addresses the nonspecificity of soporific symptoms, the health state of the individuals, and the existence of a motion stimulus.

Recipe for fatigue: sleep, work patterns, and well-being of galley workers on surface ships of the US Navy.

Study Objectives: The purpose of the study was to compare the fatigue levels, work/rest patterns, health-related behaviors, and well-being of galley workers with other sailors on US Navy ships while underway. Methods: Analysis was based on a retrospective comparison of data from 3 fit-for-duty groups of sailors: 67 galley workers, 192 non-watchstanders, and 466 watchstanders. Participants completed questionnaires (Epworth Sleepiness Scale [ESS], Insomnia Severity Index [ISI], Pittsburgh Sleep Quality Index [PSQI], and Profile of Mood States [POMS]) and activity logs, and wore actigraphs. Results: Galley workers slept MD = 6.57 (IQR = 1.42) h/d and worked MD = 12.8 (IQR = 2.42) h/d. Approximately 84% of the galley workers were classified as poor sleepers, ~57% reported having excessive daytime sleepiness (EDS), and ~38% reported elevated insomnia symptoms. Compared to non-watchstanders, galley workers had worse scores on POMS (total mood disturbance, tension-anxiety, depression, anger-hostility, fatigue, and confusion-bewilderment), ESS, ISI, and PSQI. Compared to non-watchstanders, galley workers had a higher risk for symptoms of EDS (75%), symptoms of clinically relevant insomnia (126%), and for being classified as poor sleepers (27%). Galley workers slept less and worked on average 2 h/d more than non-watchstanders. Compared to watchstanders, galley workers had worse ESS, ISI, and anger-hostility scores. More watchstanders napped compared to galley workers. Conclusions: Although they are considered day workers, the sleep patterns, fatigue levels, and mood of galley workers are comparable to, or worse than, watchstanders or other non-watchstanders. To ameliorate the effects of long work hours on sailor well-being, ship leadership should consider adopting strategies to improve galley workers' well-being.

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

Study Objectives: 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. Methods: 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. Results: 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. Conclusions: 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.

Sex differences in US military personnel with insomnia, obstructive sleep apnea, or comorbid insomnia and obstructive sleep apnea.

STUDY OBJECTIVES: The aim of this study was to evaluate sex-related differences in symptoms of sleep disorders, sleep-related impairment, psychiatric symptoms, traumatic brain injury, and polysomnographic variables in treatment-seeking military personnel diagnosed with insomnia, obstructive sleep apnea (OSA), or comorbid insomnia and OSA (COMISA). METHODS: Participants were 372 military personnel (46.2% women, 53.8% men) with an average age of 37.7 (standard deviation = 7.46) years and median body mass index of 28.4 (5.50) kg/m2. Based on clinical evaluation and video-polysomnography, participants were diagnosed with insomnia (n = 118), OSA (n = 118), or COMISA (n = 136). Insomnia severity, excessive daytime sleepiness, sleep quality, nightmare disorder, sleep impairment, fatigue, posttraumatic stress disorder, anxiety, depression symptoms, and traumatic brain injury were evaluated with validated self-report questionnaires. Descriptive statistics, parametric and nonparametric t-tests, and effect sizes were used to assess sex differences between men and women. RESULTS: There were no significant differences between women and men with insomnia or OSA in sleep-related symptoms, impairment, or polysomnography-based apnea-hypopnea index. Military men with COMISA had a significantly greater apnea-hypopnea index as compared to military women with COMISA, but women had greater symptoms of nightmare disorder, posttraumatic stress disorder, and anxiety. CONCLUSIONS: In contrast to civilian studies, minimal differences were observed in self-reported sleep symptoms, impairment, and polysomnography metrics between men and women diagnosed with the most frequent sleep disorders in military personnel (ie, insomnia, OSA, or COMISA) except in those with COMISA. Military service may result in distinct sleep disorder phenotypes that differ negligibly by sex. CITATION: Mysliwiec V, Pruiksma KE, Matsangas P, et al. Sex differences in US military personnel with insomnia, obstructive sleep apnea, or comorbid insomnia and obstructive sleep apnea. J Clin Sleep Med. 2024;20(1):17-30.

Using Light to Facilitate Circadian Entrainment from Day to Night Flights.

BACKGROUND: As part of a larger project to provide recommendations regarding limitations and best practices for shifting aviators from day to night operations, a study was conducted to assess the efficacy of high energy visible (HEV) light to shift the circadian rhythm in humans. The study attempted to replicate the patterns of military aviators who could be required to shift abruptly from day to night flight operations.METHODS: Simulated flight performance and salivary melatonin levels of 10 U.S. military aviators were collected over a 3-night period using a within-subject dim light melatonin onset (DLMO) study design. Data were collected in a laboratory with participants returning home to sleep following each of the three evenings/nights of data collection. Light treatment included a single 4-h exposure of blue-enriched white light (∼1000 lux) on night 2. Data collected included melatonin levels, light exposure, sleepiness, cognitive workload, and simulated flight performance.RESULTS: The average delay in melatonin onset was 1.32 ± 0.37 h (range: 53 min to 1 h 56 min). Sleepiness (P = 0.044) and cognitive workload (P = 0.081) improved the night following the light treatment compared to the baseline. No systematic differences were identified in flight performance.DISCUSSION: The HEV light treatment successfully delayed the circadian phase of all participants even though participants' ambient light levels (including daylight) outside the laboratory were not controlled. These findings were used to develop circadian synchronization plans for aviators who are asked to transition from day to night operations. These plans will be assessed in a follow-on study in an operational unit.Shattuck NL, Matsangas P, Reily J, McDonough M, Giles KB. Using light to facilitate circadian entrainment from day to night flights. Aerosp Med Hum Perform. 2023; 94(2):66-73.

Who sleeps more and who works longer in the US Navy: Officers or enlisted personnel?

OBJECTIVES: To determine whether United States Navy (USN) officers and enlisted personnel have different sleep and work patterns while underway on USN surface ships. METHODS: Variables of interest were assessed by actigraphy, activity logs, and validated questionnaires. RESULTS: The 2 groups had similar daily sleep (officers: 6.41 ± 0.95 hrs/day; enlisted: 6.57 ± 0.97 hrs/day) and work duration. Enlisted personnel, however, were more likely to report excessive daytime sleepiness-EDS (41% more likely), clinically relevant insomnia (105%), to have both EDS and elevated insomnia (121%), to be classified as poor sleepers (17%), to use nicotine products (174%), and to forego routine exercise (57%). Enlisted personnel were 487% more likely to report all 3 of these behaviors: drink caffeinated beverages, use nicotine/tobacco products, forego routine exercise. CONCLUSIONS: Even though the work and sleep hours do not differ significantly, the state of well-being of enlisted personnel is in general lower than officers. Our findings can provide insight to Navy leadership towards improving sailor well-being and crew endurance.

Performance comparison of peripheral arterial tonometry-based testing and polysomnography to diagnose obstructive sleep apnea in military personnel.

STUDY OBJECTIVES: Obstructive sleep apnea (OSA) is increasingly common among military personnel, but diagnostic capabilities are challenged by limited capability for polysomnography (PSG). We sought to evaluate the diagnostic properties of peripheral arterial tonometry (PAT)-based home sleep apnea testing (HSAT) to accurately identify and classify OSA among active-duty military personnel. METHODS: This study was a retrospective review of all patients suspected of having OSA who completed an initial PAT-based HSAT followed by confirmatory PSG within 120 days. The diagnostic properties of a PAT-based, HSAT-derived apnea-hypopnea index (AHI) vs a PSG-derived AHI were assessed. RESULTS: Two hundred eight matched pairs of asynchronous studies were analyzed. The prevalence of OSA was 63.5%. PAT-based HSAT overdiagnosed 27.4% of patients with OSA and underdiagnosed 46.6% of patients with OSA. The majority (n = 116, 55.8%) of patients changed OSA severity classification (absent, mild, moderate, severe) after PSG. OSA severity classification concordance between PAT-based HSAT and PSG was observed in 53.4%, 40.5%, 28.6%, and 40.0% of patients with absent, mild, moderate, and severe OSA, respectively. Receiver operating characteristic curve analysis showed an area under the curve of 0.715 and a proposed PAT-based, HSAT-derived AHI cutoff score for OSA diagnosis of 9.0 events/h. This PAT-based, HSAT-derived AHI provided a 52% sensitivity, 83% specificity, 84% positive predictive value, and 50% negative predictive value. Bland-Altman plots showed an unacceptable degree of agreement between PAT-based, HSAT-derived AHI and AHI. CONCLUSIONS: There is significant discordance between PAT-based HSAT and PSG among active-duty military personnel evaluated for OSA. PAT-based HSAT may have limited utility for diagnosing OSA and grading severity in this unique patient population. CITATION: O'Reilly BM, Wang Q, Collen J, Matsangas P, Colombo CJ, Mysliwiec V. Performance comparison of peripheral arterial tonometry-based testing and polysomnography to diagnose obstructive sleep apnea in military personnel. J Clin Sleep Med. 2022;18(6):1523-1530.

Clinical and polysomnographic features of trauma associated sleep disorder.

STUDY OBJECTIVES: Trauma associated sleep disorder is a proposed parasomnia that develops after trauma with clinical features of trauma related nightmares, disruptive nocturnal behaviors, and autonomic disturbances. The purpose of this case series is to better characterize the clinical and video-polysomnographic features of patients meeting clinical criteria for this proposed parasomnia. METHODS: Semistructured clinical interview and detailed video-polysomnography review of 40 patients. Movements and vocalizations in rapid eye movement sleep were quantified according to the rapid eye movement sleep behavior disorder severity scale. RESULTS: Patients (n = 40, 32 males) were service members and veterans with a median age of 38.9 years (range 24-57 years) who reported trauma related nightmares and disruptive nocturnal behaviors at home. On video-polysomnography, 28 (71.8%) patients had disruptive nocturnal behaviors in rapid eye movement sleep consisting of limb, head, and axial movements; vocalizations were present in 8 (20%). On the rapid eye movement sleep behavior disorder severity scale, most (n = 28, 71.8%) had a low rating but those with greater severity (n = 11, 28.2%) had a higher prevalence of posttraumatic stress disorder (P = .013) and markedly less N3 sleep (P = .002). The cohort had a high rate of insomnia (n = 35, 87.5%) and obstructive sleep apnea (n = 19, 47.5%). Most patients were treated with prazosin (n = 29, 72.5%) with concomitant behavioral health interventions (n = 25, 64.1%); 15 (51.7%) patients receiving prazosin reported improved symptomatology. CONCLUSIONS: Disruptive nocturnal behaviors can be captured on video-polysomnography during rapid eye movement sleep, although they may be less pronounced than what patients report in their habitual sleeping environment. Clinical and video-polysomnographic correlations are invaluable in assessing patients with trauma associated sleep disorder to document objective abnormalities. This case series provides a further basis for establishing trauma associated sleep disorder as a unique parasomnia. CITATION: Brock MS, Matsangas P, Creamer JL, et al. Clinical and polysomnographic features of trauma associated sleep disorder. J Clin Sleep Med. 2022;18(12):2775-2784.