Measurement validity of the six-factor model of psychological well-being in a military sample: Implications for measuring well-being in service members.

Subjective well-being is a positive psychological construct that has important implications for the U.S. Military's goal to develop service members' strengths and support their overall thriving and downstream resilience. Despite this, the concept of well-being has not been well studied in military populations who have unique work demands, stressors, and autonomy/agency in daily life compared to civilians. To address this shortcoming in the literature, the present study assessed Ryff's measures of psychological well-being (PWB) in 1,333 U.S. service members prior to the deployments in the Middle East. Various methods attempting to validate the theoretical model purported by Ryff were unsuccessful, and exploratory factor analyses did not result in a novel model for this population. Future research should continue to evaluate proposed models of soldier well-being and propose novel theories, as well as measures, to assess this important construct. Implications are discussed. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Sleep and Infantry Battle Drill Performance in Special Operations Soldiers.

BACKGROUND: Although multiple studies have documented the impact of insufficient sleep on soldier performance, most studies have done so using artificial measures of performance (e.g., tablet or simulator tests). The current study sought to test the relationship between sleep and soldier performance during infantry battle drill training, a more naturalistic measure of performance.METHODS: Subjects in the study were 15 junior Special Operations infantry soldiers. Soldiers wore an actigraph and reported their subjective sleep duration and quality prior to close quarter battle (CQB) drills. Experienced leaders monitored each iteration of the CQB exercise and recorded the number of errors committed.RESULTS: The number of errors committed during the live ammunition iterations was negatively correlated with subjective number of hours slept and subjective sleep efficiency/quality during the month prior. Soldiers with subjective sleep duration ≥7 h had a significantly lower number of errors than soldiers with subjective sleep duration <7 h (1.71 vs. 0.63 errors), and soldiers with sleep quality <85% committed more errors than those with sleep quality ≥85% (1.50 vs. 0.40 errors).DISCUSSION: These data preliminarily suggest that sleep quality and duration may influence subsequent performance on infantry battle drill training, particularly for soldiers with limited experience in battle drill conduction who have not yet perfected battle drill techniques. Future studies should enact sleep augmentation to determine the causal influence of sleep on performance in this setting.Mantua J, Shevchik JD, Chaudhury S, Eldringhoff HP, Mickelson CA, McKeon AB. Sleep and infantry battle drill performance in Special Operations soldiers. Aerosp Med Hum Perform. 2022; 93(7):557-561.

Trajectories of Insomnia in Adults After Traumatic Brain Injury.

Importance: Insomnia is common after traumatic brain injury (TBI) and contributes to morbidity and long-term sequelae. Objective: To identify unique trajectories of insomnia in the 12 months after TBI. Design, Setting, and Participants: In this prospective cohort study, latent class mixed models (LCMMs) were used to model insomnia trajectories over time and to classify participants into distinct profile groups. Data from the Transforming Research and Clinical Knowledge in Traumatic Brain Injury (TRACK-TBI) study, a longitudinal, multisite, observational study, were uploaded to the Federal Interagency Traumatic Brain Injury Repository (FITBIR) database. Participants were enrolled at 1 of 18 participating level I trauma centers and enrolled within 24 hours of TBI injury. Additional data were obtained directly from the TRACK-TBI investigators that will be uploaded to FITBIR in the future. Data were collected from February 26, 2014, to August 8, 2018, and analyzed from July 1, 2020, to November 15, 2021. Exposures: Traumatic brain injury. Main Outcomes and Measures: Insomnia Severity Index assessed serially at 2 weeks and 3, 6, and 12 months thereafter. Results: The final sample included 2022 participants (1377 [68.1%] men; mean [SD] age, 40.1 [17.2] years) from the FITBIR database and the TRACK-TBI study. The data were best fit by a 5-class LCMM. Of these participants, 1245 (61.6%) reported persistent mild insomnia symptoms (class 1); 627 (31.0%) initially reported mild insomnia symptoms that resolved over time (class 2); 91 (4.5%) reported persistent severe insomnia symptoms (class 3); 44 (2.2%) initially reported severe insomnia symptoms that resolved by 12 months (class 4); and 15 (0.7%) initially reported no insomnia symptoms but had severe symptoms by 12 months (class 5). In a multinomial logistic regression model, several factors significantly associated with insomnia trajectory class membership were identified, including female sex (odds ratio [OR], 1.65 [95% CI, 1.02-2.66]), Black race (OR, 2.36 [95% CI, 1.39-4.01]), history of psychiatric illness (OR, 2.21 [95% CI, 1.35-3.60]), and findings consistent with intracranial injury on computed tomography (OR, 0.36 [95% CI, 0.20-0.65]) when comparing class 3 with class 1. Conclusions and Relevance: These results suggest important heterogeneity in the course of insomnia after TBI in adults. More work is needed to identify outcomes associated with these insomnia trajectory class subgroups and to identify optimal subgroup-specific treatment approaches.

Perceptions of purpose, cohesion, and military leadership: A path analysis of potential primary prevention targets to mitigate suicidal ideation.

Rates of suicide in the US Army continue to rise, and by some accounts exceed the general population. This increase has renewed efforts to identify protective factors that may inform novel suicide prevention strategies. Previous research has demonstrated that a sense of purpose in life and perceived cohesion with military peers are related to a reduction in the severity of suicidal ideation (SI). Additionally, research in military samples supports decreased SI in Soldiers who endorse that their leaders convey a sense of purpose and meaning in their shared mission. However, no work has investigated whether these leadership styles relate to a sense of felt purpose and perceived cohesion in Soldiers and thus the indirect effect of these leadership styles on SI. Active duty Army Soldiers (n = 1,160) completed self-report measures of purpose in life (PiL), perceived cohesion, ethical leadership, loneliness, and SI. Indirect effect analyses were conducted to determine how leadership behaviors indirectly relate to SI through PiL and perceived cohesion. Indirect effect analyses revealed that ethical leadership had an indirect effect on reduced SI through increased PiL. In the same parallel indirect effect analysis, ethical leadership was related to less SI through increased perceived cohesion and decreased loneliness sequentially. Enhanced leadership training that effectively increases Soldier purpose may be an important primary prevention tool to mitigate the effect of suicide risk factors. This primary prevention strategy may help augment existing suicide surveillance and clinical prevention efforts to reduce Soldier risk for suicide.

Transitioning from daytime to nighttime operations in military training has a temporary negative impact on dynamic balance and jump performance in U.S. Army Rangers.

OBJECTIVES: Explore the impact transitioning from daytime to nighttime operations has on performance in U.S. Army Rangers. METHODS: Fifty-four male Rangers (age 26.1±4.0 years) completed the Y-Balance Test (YBT), a vertical jump assessment, and a grip strength test at three time points. Baseline testing occurred while the Rangers were on daytime operations; post-test occurred after the first night into the nighttime operation training (after full night of sleep loss), and follow-up testing occurred six days later (end of nighttime training). RESULTS: On the YBT, performance was significantly worse at post-test compared to baseline during right posteromedial reach (104.1±7.2cm vs 106.5±6.7cm, p=.014), left posteromedial reach (105.4±7.5cm vs 108.5±6.6cm, p=.003), right composite score (274.8±19.3cm vs 279.7±18.1cm, p=.043), left composite score (277.9±18.1cm vs 283.3±16.7cm, p=.016), and leg asymmetry was significantly worse in the posterolateral direction (4.8±4.0cm vs 3.7±3.1cm, p=.030) and the anterior direction (5.0±4.0cm vs 3.6±2.6cm, p=.040). The average vertical jump height was significantly lower at post-test compared to baseline (20.6±3.4 in vs 21.8±3.0 in, p=.004). Baseline performance on YBT and vertical jump did not differ from follow-up. CONCLUSIONS: Army Rangers experienced an immediate, but temporary, drop in dynamic balance and vertical jump performance when transitioning from daytime to nighttime operations. When feasible, Rangers should consider adjusting their sleep cycles prior to anticipating nighttime operations in order to maintain their performance levels. Investigating strategies that may limit impairments during this transition is warranted.

Sleep and occupational well-being in active duty special operations soldiers: A replication and expansion.

OBJECTIVE: To assess the relationship between sleep quality and occupational well-being in active duty military Service Members. DESIGN: Longitudinal prospective analysis. SETTING: An annual military training event. PARTICIPANTS: US Army special operations Soldiers (n = 60; 100% male; age 25.41 ± 3.74). INTERVENTION: None. MEASUREMENTS: The Pittsburgh Sleep Quality Index (PSQI) was administered prior to the training event, and the Emotional Exhaustion Scale, the Role Overload Scale, the Walter Reed Army Institute of Research Soldier-Specific Functional Impairment Scale, and the Perceived Stress Scale were administered after the event. Linear regression models were used to assess the relationship between sleep and occupational wellness measures, and the outcome measures of "good" and "poor" sleepers (per the PSQI scoring criteria) were compared with Student's t tests. RESULTS: Higher (poorer) PSQI Global Scores predicted poorer occupational wellness of all measures (emotional exhaustion: B = 1.60, P < .001, R2 = 0.25; functional impairment: B = 0.29, P = .03, R2 = 0.14; role overload: B = 0.28, P = .008, R2 = 0.12; and perceived stress: B = 0.34, P = .004, R2 = 0.20). There were additional relationships between specific PSQI component scores and occupational wellness measures, which is a replication of This team's previous work. Furthermore, emotional exhaustion (t(58) = -4.18, P < .001), functional impairment (t(59)= -3.68, P = .001), role overload (t(58) = -3.20, P = .002), and perceived stress (t(58) = -2.43, P = .02) were all higher in poor sleepers. CONCLUSIONS: The findings of this study suggest that US Army special operations Soldiers who have poorer sleep quality may be at increased risk for having poorer occupational well-being.

Sleep and high-risk behavior in military service members: a mega-analysis of four diverse U.S. Army units.

Experimental sleep restriction and deprivation lead to risky decision-making. Further, in naturalistic settings, short sleep duration and poor sleep quality have been linked to real-world high-risk behaviors (HRB), such as reckless driving or substance use. Military populations, in general, tend to sleep less and have poorer sleep quality than nonmilitary populations due to a number of occupational, cultural, and psychosocial factors (e.g. continuous operations, stress, and trauma). Consequently, it is possible that insufficient sleep in this population is linked to HRB. To investigate this question, we combined data from four diverse United States Army samples and conducted a mega-analysis by aggregating raw, individual-level data (n = 2,296, age 24.7 ± 5.3). A negative binomial regression and a logistic regression were used to determine whether subjective sleep quality (Pittsburgh Sleep Quality Index [PSQI], Insomnia Severity Index [ISI], and duration [h]) predicted instances of military-specific HRB and the commission of any HRB (yes/no), respectively. Poor sleep quality slightly elevated the risk for committing HRBs (PSQI Exp(B): 1.12 and ISI Exp(B): 1.07), and longer duration reduced the risk for HRBs to a greater extent (Exp(B): 0.78), even when controlling for a number of relevant demographic factors. Longer sleep duration also predicted a decreased risk for commission of any HRB behaviors (Exp(B): 0.71). These findings demonstrate that sleep quality and duration (the latter factor, in particular) could be targets for reducing excessive HRB in military populations. These findings could therefore lead to unit-wide or military-wide policy changes regarding sleep and HRB.

Sleep loss is related to unstable stationary balance in U.S. Army soldiers in an operationally-relevant context.

BACKGROUND: Sleep loss negatively impacts stationary balance in a laboratory setting, but few studies have examined this link in a naturalistic environment. We tested this relationship in U.S. Army soldiers that often undergo mission-driven sleep loss and who conduct high-risk operations on precarious terrain. METHODS: Stationary balance was tested before and after a mission night. RESULTS: After mission-driven sleep loss, in more difficult conditions (but not easy conditions) balance was more unstable and more variable than a rested baseline condition. Furthermore, habitual sleep quality prior to sleep loss predicted the balance decrement after sleep loss. CONCLUSIONS: Therefore, mission-driven sleep loss may negatively impact soldier balance, but better sleep prior to the mission may mitigate these negative effects.

Practice parameters for the use of actigraphy in the military operational context: the Walter Reed Army Institute of Research Operational Research Kit-Actigraphy (WORK-A).

BACKGROUND: The Walter Reed Army Institute of Research (WRAIR) Operational Research Kit-Actigraphy (WORK-A) is a set of unique practice parameters and actigraphy-derived measures for the analysis of operational military sleep patterns. The WORK-A draws on best practices from the literature and comprises 15 additional descriptive variables. Here, we demonstrate the WORK-A with a sample of United States Army Reserve Officers' Training Corps (ROTC) cadets (n = 286) during a month-long capstone pre-commissioning training exercise. METHODS: The sleep of ROTC cadets (n = 286) was measured by Philips Actiwatch devices during the 31-day training exercise. The preliminary effectiveness of the WORK-A was tested by comparing differences in sleep measures collected by Actiwatches as calculated by Philips Actiware software against WORK-A-determined sleep measures and self-report sleep collected from a subset of ROTC cadets (n = 140). RESULTS: Actiware sleep summary statistics were significantly different from WORK-A measures and self-report sleep (all P ≤ 0.001). Bedtimes and waketimes as determined by WORK-A major sleep intervals showed the best agreement with self-report bedtime (22:21 ± 1:30 vs. 22:13 ± 0:40, P = 0.21) and waketime (04:30 ± 2:17 vs. 04:31 ± 0:47, P = 0.68). Though still significantly different, the discrepancy was smaller between the WORK-A measure of time in bed (TIB) for major sleep intervals (352 ± 29 min) and self-report nightly sleep duration (337 ± 57 min, P = 0.006) than that between the WORK-A major TIB and Actiware TIB (177 ± 42, P ≤ 0.001). CONCLUSIONS: Default actigraphy methods are not the most accurate methods for characterizing soldier sleep, but reliable methods for characterizing operational sleep patterns is a necessary first step in developing strategies to improve soldier readiness. The WORK-A addresses this knowledge gap by providing practice parameters and a robust variety of measures with which to profile sleep behavior in service members.

Traumatic brain injury and sleep disturbances in combat-exposed service members and veterans: Where to go next?

OBJECTIVE: To synthesize the current evidence on sleep disturbances in military service members (SMs) and veterans with traumatic brain injury (TBI). METHODS: An electronic literature search first identified abstracts published from 2008-2018 inclusively referencing sleep, TBI, and military personnel from Operation Enduring Freedom, Operation Iraqi Freedom, Operation New Dawn, and Persian Gulf veterans. Selection criteria eliminated studies on non-combat TBI, open or penetrating injuries, and articles where the relationship between sleep and TBI was not directly examined. Articles on all military branches and components, those currently serving and veterans-ranging from medical chart reviews to clinical trials, were included. Forty-one articles were selected for full text-review. RESULTS: Twenty-four papers estimated the prevalence of sleep disturbances in TBI. Eight studies demonstrated the contribution of common co-occurring conditions, most notably posttraumatic stress disorder, to the relationship between disrupted sleep and TBI. Ten studies differentiated sleep profiles between military SMs and veterans with and without acute TBI and detected significant differences in sleep disturbances across the course of injury. Longitudinal studies were scarce but helped to establish the temporal relationship between sleep disturbances and TBI and isolate sleep-related mechanisms influencing TBI prognosis. Only three studies reported on interventions for improving sleep quality and TBI symptoms. Systematic research testing assessments and interventions that target sleep disturbances for improving sleep, TBI symptoms, and long-term functional outcomes were identified as critical knowledge gaps. CONCLUSION: Findings unequivocally establish that sleep disturbances are highly prevalent in SMs and veterans with TBI. However, studies testing the effectiveness of treatments for improving sleep in military groups with TBI have been limited and their results inconsistent. This review highlights a critical opportunity for advancing military medicine through future research aimed at identifying and testing sleep-focused treatments in SMs and veterans with combat-related TBI.

Sleep, Sleep Disorders, and Circadian Health following Mild Traumatic Brain Injury in Adults: Review and Research Agenda.

A rapidly expanding scientific literature supports the frequent co-occurrence of sleep and circadian disturbances following mild traumatic brain injury (mTBI). Although many questions remain unanswered, the preponderance of evidence suggests that sleep and circadian disorders can result from mTBI. Among those with mTBI, sleep disturbances and clinical sleep and circadian disorders contribute to the morbidity and long-term sequelae across domains of functional outcomes and quality of life. Specifically, along with deterioration of neurocognitive performance, insufficient and disturbed sleep can precede, exacerbate, or perpetuate many of the other common sequelae of mTBI, including depression, post-traumatic stress disorder, and chronic pain. Further, sleep and mTBI share neurophysiologic and neuroanatomic mechanisms that likely bear directly on success of rehabilitation following mTBI. For these reasons, focus on disturbed sleep as a modifiable treatment target has high likelihood of improving outcomes in mTBI. Here, we review relevant literature and present a research agenda to 1) advance understanding of the reciprocal relationships between sleep and circadian factors and mTBI sequelae and 2) advance rapidly the development of sleep-related treatments in this population.

Sleep in PTSD: Conceptual model and novel directions in brain-based research and interventions.

Peri-traumatic sleep disturbances are growingly recognized as biologically-relevant and modifiable predisposing, precipitating, and perpetuating factors in posttraumatic stress disorder (PTSD). The exponential growth of the literature on sleep in PTSD over the last two decades has stimulated a paradigm shift in the conceptualization of the relationship between sleep and PTSD. A conceptual framework that captures this paradigm shift is offered. New research on existing and promising sleep-focused treatments for augmenting PTSD treatment outcomes is then summarized. New findings on the neurobiological correlates and underpinnings of the relationship between sleep and PTSD are also discussed. Informed by these recent findings and foundational literature, opportunities for innovation in clinical and experimental research are proposed.

Hierarchical Linear Modeling for Analysis of Ecological Momentary Assessment Data in Physical Medicine and Rehabilitation Research.

Ecological momentary assessment (EMA) methods collect real-time data in real-world environments, which allow physical medicine and rehabilitation researchers to examine objective outcome data and reduces bias from retrospective recall. The statistical analysis of EMA data is directly related to the research question and the temporal design of the study. Hierarchical linear modeling, which accounts for multiple observations from the same participant, is a particularly useful approach to analyzing EMA data. The objective of this paper was to introduce the process of conducting hierarchical linear modeling analyses with EMA data. This is accomplished using exemplars from recent physical medicine and rehabilitation literature.