Military Population Research Articles

Prospective Evaluation of Push-up Performance and Patient-Reported Outcomes Following Open Dorsal Wrist Ganglion Excision in the Active-Duty Military Population.

Background Dorsal wrist ganglia (DWG) are a common wrist pathology that affects the military population. This study prospectively evaluates push-up performance, functional measures, and patient-reported outcomes 6 months after open DWG excision in active-duty patients. Methods Twenty-seven active-duty patients were enrolled and 18 had complete follow-up. Included patients had DWG diagnosis, unilateral involvement, and no previous surgery. The number of push-ups performed within 2 minutes was measured preoperatively and at 6 months. Range of motion (ROM), grip strength, Pain Catastrophization Scale (PCS), Disabilities of the Arm, Shoulder, and Hand (DASH) score, Mayo Wrist Score, and visual analog scale (VAS) pain score were measured preoperatively and at 2 weeks, 6 weeks, 3 months, and 6 months. Results Push-up performance did not significantly change overall. Wrist flexion, extension, and radial deviation returned to preoperative ranges. Wrist ulnar deviation significantly increased from preoperative range. Grip strength deficit between operative and unaffected extremities significantly improved to 0.7 kg at 6 months from preoperative deficit of 2.7 kg. Mean scores significantly improved for the validated outcome measures-PCS from 6.3 to 0.67, VAS pain scores from 1.37 to 0.18, DASH scores from 12.8 to 4.3, and Mayo Wrist Scores from 80.3 to 89.4. No surgical complications or recurrences were reported. Conclusions Findings suggest that almost half of active patients may improve push-up performance after DWG excision at 6 months. Significant improvements were seen in wrist pain, ROM, grip strength, and all patient-reported outcomes, which is useful when counseling patients undergoing excision.

Adverse childhood experiences and mental health in military recruits: Exploring gender as a moderator.

Adverse childhood experiences (ACEs) have consistently been associated with adult psychopathology and are commonly reported among military populations, with women more likely to report many types of ACEs than men. Limited research has examined the role of gender in the association between ACEs and mental health in military populations. The current study assessed the significance of gender differences in ACEs and mental health and explored the associations among these variables in a sample of Canadian Armed Forces recruits/officer cadets. Analyses with cross-sectional Recruit Health Questionnaire (RHQ) data from 50,603 recruits/officer cadets indicated that women were more likely to report witnessing domestic violence, experiencing sexual abuse, and living with someone with mental health problems or alcohol misuse, odds ratios (ORs) = 1.22-4.35, ps < .001. Women were more likely to screen positive for depression, adjusted (aORs) = 1.25-1.49, p < .001-p = .002, and anxiety, aORs = 2.00-2.33, ps < .001, before basic military training. ACEs were associated with screening positive for probable mental health conditions, aORs = 1.54-6.13, p < .001-p = .017. A significant interaction suggested the association between childhood sexual abuse and depression was stronger for men, aOR = 2.49, p < .001, than women, aOR = 1.63, p = .002, as was the association between childhood sexual abuse and posttraumatic stress disorder, men: aOR = 6.06, p < .001, women: aOR = 3.36, p < .001. These results underscore the importance of considering gender and childhood trauma in mental health interventions with military personnel.

Tibial Bone Geometry Is Associated With Bone Stress Injury During Military Training in Men and Women.

Bone stress injuries (BSI) are a common musculoskeletal condition among exercising and military populations and present a major burden to military readiness. The purpose of this investigation was to determine whether baseline measures of bone density, geometry, and strength, as assessed via peripheral quantitative computed tomography (pQCT), are predictive of tibial BSI during Marine Officer Candidates School training. Tibial pQCT scans were conducted prior to the start of physical training (n = 504; Male n = 382; Female n = 122) to measure volumetric bone mineral density (vBMD), geometry, robustness, and estimates of bone strength. Bone parameters were assessed at three tibial sites including the distal metaphysis (4% of tibial length measured from the distal endplate), mid-diaphysis (38% of tibial length measured from the distal endplate), and proximal diaphysis (66% of tibial length measured from the distal endplate). Injury surveillance data was collected throughout training. Four percent (n = 21) of the sample were diagnosed with a BSI at any anatomical site during training, 10 injuries were of the tibia. Baseline bone parameters were then tested for associations with the development of a tibial BSI during training and it was determined that cortical bone measures at diaphyseal (38 and 66%) sites were significant predictors of a prospective tibial BSI. At the mid-diaphysis (38% site), in a simple model and after adjusting for sex, age, and body size, total area [Odds Ratio (OR): 0.987, 0.983], endosteal circumference (OR: 0.853, 0.857), periosteal circumference (OR: 0.863, 0.824), and estimated bending strength (SSI; OR: 0.998, 0.997) were significant predictors of a BSI during training, respectively, such that lower values were associated with an increased likelihood of injury. Similarly, at the proximal diaphysis (66% site), total area (OR: 0.989, 0.985), endosteal circumference (OR: 0.855, 0.854), periosteal circumference (OR: 0.867, 0.823), robustness (OR: 0.007, 0.003), and SSI (OR: 0.998, 0.998) were also significant predictors of BSI in the simple and adjusted models, respectively, such that lower values were associated with an increased likelihood of injury. Results from this investigation support that narrower bones, with reduced circumference, lower total area, and lower estimated strength are associated with increased risk for tibial BSI during military training.

Attentional bias in German Armed Forces veterans with and without posttraumatic stress symptoms – An eye-tracking investigation and group comparison

Background and objectivesMost eye tracking based paradigms evidence patterns of sustained attention on threat coupled with low evidence for vigilance to or avoidance of threat in posttraumatic stress symptoms (PTSS). Still, eye tracking data on attention bias is particularly limited for military population. This eye tracking study investigated attentional bias in PTSS in a sample of German Armed Forces veterans. MethodsVeterans with deployment-related PTSS (N = 24), veterans with deployment-related traumatization without PTSS (N = 28), and never-deployed healthy veterans (N = 18) were presented with pairs of combat and neutral pictures, pairs of general threat and neutral pictures, and pairs of emotional and neutral faces. Their eye gazes were tracked during a free viewing task. 3 x 3 x 2 mixed general linear model analyses were conducted. Internal consistency of attention bias indicators was calculated for the entire sample and within groups. ResultsVeterans with PTSS dwelled longer on general threat AOIs in contrast to non-exposed controls and shorter on general threat and combat associated neutral AOIs in contrast to both control groups. Veterans with PTSS entered faster to general threat AOIs than non-exposed controls. Veterans with PTSS showed circumscribed higher attention fluctuation in contrast to controls. Internal consistency varied across attention bias indicators. LimitationsStatistical power was reduced due to recruitment difficulties. ConclusionsEvidence is provided for the maintenance hypothesis in PTSS. No robust evidence is provided for hypervigilant behavior in PTSS. Findings on attention bias variability remain unclear, calling for more investigations in this field.

Developing Biomarkers of Mild Traumatic Brain Injury: Promise and Progress of CNS-Derived Exosomes.

Mild traumatic brain injuries (mTBI) are common injuries across civilian and military populations. Although most individuals recover after mTBI, some individuals continue to show long-term symptoms as well as increased risk for neurodegenerative and neuropsychiatric disorders. Currently, diagnosing TBI severity relies primarily on self-report and subjective symptoms, with limited tools for diagnosis or prognosis. Brain-derived exosomes, a form of extracellular vesicle, may offer a solution for interpreting injury states by aiding in diagnosis as well as outcome prediction with relatively low patient burden. Exosomes, which are released into circulation, contain both protein and RNA cargo that can be isolated and quantified, providing a molecular window into molecular status of the exosome source. Here we examined the current literature studying the utility of exosomes, in particular neuronal- and astrocyte-derived exosomes, to identify protein and miRNA biomarkers of injury severity, trajectory, and functional outcome. Current evidence supports the potential for these emerging new tools to capture an accessible molecular window into the brain as it responds to a traumatic injury, however a number of limitations must be addressed in future studies. Most current studies are relatively small and cross sectional; prospective, longitudinal studies across injury severity, and populations are needed to track exosome cargo changes after injury. Standardized exosome isolation as well as advancement in identifying/isolating exosomes from CNS-specific tissue sources will improve mechanistic understanding of cargo changes as well as reliability of findings. Exosomes are also just beginning to be used in model systems to understand functional effects of TBI-associated cargo such as toxicity. Finally linking exosome cargo changes to objective markers of neuronal pathology and cognitive changes will be critical in validating these tools to provide insights into injury and recovery states after TBI.

Mechanism of the traumatic brain injury induced by blast wave using the energy assessment method

Although blast-induced traumatic brain injury (b-TBI) is well recognized for its significance in the military population, the unique mechanisms of primary b-TBI remain undefined. The aim of the present study is to unveil the mechanism of the traumatic brain injury induced by the shock wave using the energy assessment method. First, the magnetic resonance images of the human head were processed to establish the finite element (FE) model of the human head including the skin, the skull, the brain and other structures. The simulation of the shock wave was implemented using the Coupled Eulerian-Lagrange (CEL) method, a fluid-solid coupling model of explosive shock wave-head. The coupled model was used to simulate the situations of head subjected to the frontal direction, the side direction and the rear direction by explosive shock wave. The predictions of the FE results were validated by comparing them with previous studies. Then, the degree of b-TBI in three different directions i.e., the frontal direction, the side direction and the rear direction, was assessed to investigate the influence of the direction of the shock wave on the b-TBI. Finally, the various energies including strain energy, kinetic energy, viscous energy and creep energy were extracted from the FE calculations for investigating the mechanism of b-TBI. The results showed that under the scenario of the shock wave, the brain injury was caused by the combined actions of acceleration of the head and the deformation of the skin& facial muscle tissues, the brain and the cerebrospinal fluid (CSF). In addition, it was also found that the dissipation capacity of the head was not sensitive to the impact direction. The present study provides important data and theoretical basis for the mechanism of b-TBI.

Feasibility and reliability of the Functional Movement Screen battery in adults with intellectual disability.

BackgroundThe feasibility and reliability of the Functional Movement Screen (FMS) battery for predicting injury risk have been widely studied in athletic, military, public service and healthy populations. However, scant research has been carried out in people with disabilities. This study aimed at identifying the feasibility and reliability of the FMS battery when administered to adults with intellectual disability (ID).MethodsAdults from a residential and day care centre over 18 years of age, diagnosed with ID and able to follow simple instructions, were included in the study. All participants with behavioural or health problems that prevented the completion of the FMS battery were excluded. All exercises were video recorded to assure proper scoring. Three assessors (one trained and two novices) scored each of the FMS subtests performed separately from the videos. Feasibility was based on completion rates. Reliability of the composite test scores was analysed using intraclass correlation coefficients (ICCs).ResultsA total of 30 people with ID (mean age: 35.5 ± 7.12 years; 33.3% women) completed all assessments. The battery showed to be feasible, although difficulties when performing two of the subtests were observed among those with moderate and severe ID. Mean total scores from the three assessors ranged from 7.83 to 8.90. An inverse trend was observed indicating that the higher the ID level, the lower the total FMS score. Test–retest reliability was good for the trained assessor (ICC = 0.89) and mostly moderate for both novice assessors (ICC range: 0.60 to 0.76). Moderate to good inter‐rater reliability was observed (ICC range: 0.65 to 0.80).ConclusionThe FMS battery is a reliable tool that can be performed by people with ID, albeit with certain difficulties, especially in those with moderate to severe impairment. The battery does not seem to be useful for identifying people with ID at risk of suffering a sport injury. Adequately powered, well‐designed studies are required to determine if the FMS battery is appropriate for identifying changes in functional performance in this population.

Clinical features of dementia cases ascertained by ICD coding in LIMBIC-CENC multicenter study of mild traumatic brain injury

ABSTRACT Objective Describe dementia cases identified through International Classification of Diseases (ICD) coding in the Long-term Impact of Military-relevant Brain Injury Consortium – Chronic Effects of Neurotrauma Consortium (LIMBIC-CENC) multicenter prospective longitudinal study (PLS) of mild traumatic brain injury (mTBI). Design Descriptive case series using cross-sectional data. Methods Veterans Affairs (VA) health system data including ICD codes were obtained for 1563 PLS participants through the VA Informatics and Computing Infrastructure (VINCI). Demographic, injury, and clinical characteristics of Dementia positive and negative cases are described. Results Five cases of dementia were identified, all under 65 years old. The dementia cases all had a history of blast-related mTBI and all had self-reported functional problems and four had PTSD symptomatology at the clinical disorder range. Cognitive testing revealed some deficits especially in the visual memory and verbal learning and memory domains, and that two of the cases might be false positives. Conclusions ICD codes for early dementia in the VA system have specificity concerns, but could be indicative of cognitive performance and self-reported cognitive function. Further research is needed to better determine links to blast exposure, blast-related mTBI, and PTSD to early dementia in the military population.

Respiratory Infections Are More Common Than Healthcare Records Indicate: Results From an Anonymous Survey.

ABSTRACTIntroductionInfluenza-like illnesses (ILIs) are common in military populations and can impair mission-readiness, particularly in the current severe acute respiratory syndrome coronavirus 2 pandemic; therefore, it is important to identify potential risk factors for infection and better understand the burden of infection.Materials and MethodsA survey was administered to military medical trainees living in a congregated setting on JBSA Fort Sam Houston, Texas, from January 2017 to February 2019. The survey included questions about ILI experience and potential ILI risk factors.Results2,121 individuals completed the survey. Respondents had a median age of 21 years, 46% were female, 32.6% were Air Force, 33.6% were Army, and 33.8% were Navy/Marines. Among the 815 (38%) who reported an ILI during training, 40% sought health care. The primary reasons for seeking healthcare included illness severity, concern about transmission, and accessibility of healthcare. Over half (54%) of the trainees who reported an ILI said the ILI had an impact on their performance, including reduced study time, missed physical training, and missed class. Multivariate model results indicate that women and younger trainees (<30 years) were more likely to report having had an ILI (women: OR 1.58, (95% CI 1.30, 1.92); age <30 years: OR 1.58, (1.06, 2.36)). In a subset analysis, those who reported washing their hands 10+ times per day were less likely to report an ILI (OR 0.61 (0.42, 0.89)).ConclusionsILIs are likely to be more common during training than healthcare records indicate and may result in decreased training effectiveness. Increasing access to handwashing facilities and education about the importance of handwashing to prevent the spread of disease will likely reduce the ILI burden in this population.

Ankle sprain bracing solutions and future design consideration for civilian and military use

ABSTRACT Introduction Ankle sprains are common injuries within the civilian and military populations, with lingering symptoms that include pain, swelling, giving-way, and a high likelihood for recurrence. Numerous bracing systems are available to stabilize the ankle joint following sprains, with new design iterations frequently entering the market. Currently available braces generally include sleeve, lace-up, and stirrup designs. Sleeves provide mild compression and warmth but limited stability for the ankle, while lace-ups and stirrups appear to be more effective at preventing and treating lateral ankle sprains. Areas covered This review summarizes the use of various brace options in practice. Their major clinical benefits, and limitations are highlighted, followed by an overview of emerging concepts in brace design. Current advancements in biomechanical simulation, multifunctional material fabrication, and wearable, field-deployed devices for human injury surveillance are discussed, providing possibilities for conceiving new design concepts for next-generation smart ankle braces. Expert opinion Performance of the commercially available braces are limited by their current design concepts. Suggestions on future brace design include: (1) incorporating high-performance materials suitable for extreme environments, (2) leveraging modeling and simulation techniques to predict mechanical support requirements, and (3) implementing adaptive, customizable componentry material to meet the needs of each unique patient.

Development of a Rat Model of Fasciotomy Treatment for Compartment Syndrome.

Skeletal muscle injuries are a major cause of disability for military and civilian populations. Compartment syndrome (CS) in skeletal muscle results from an edema-induced increase in intracompartmental pressure (ICP) after primary injury. Untreated ICP will occlude the tissue vasculature, tissue necrosis, and potential loss of limb. The current standard of care for CS is surgical fasciotomy, an incision through the muscle fascia to relieve ICP. Early fasciotomy will preserve the limb, but often leaves patients with long-term scarring and reduced muscle function. Our group previously developed and characterized a rat model of CS to explore the pathophysiology of CS and test new therapies. We present an expansion of this CS model, including the fasciotomy, to better simulate clinical treatment. CS was induced on the hind limb of adult male Lewis rats and fasciotomy was performed 24 h later. Less than 20% of the rats that underwent fasciotomy showed detectable force 4 days after injury, compared with the 75% of rats that underwent CS induction without fasciotomy. Muscles undergoing fasciotomy showed a significant increase in fibrosis and an increased number of macrophages, Pax7+ satellite cells, and α-smooth muscle actin+ myofibroblasts at 7 days postinjury. These data indicate that the use of fasciotomy in a rat model of CS resulted in injury sequelae that reflect the severity of human clinical disease presentation along with current standard of care. Impact Statement Current animal models of skeletal muscle injury struggle to accurately reflect the injury sequelae seen in humans, particularly in rats and mice. These animals also recover faster than humans do. More accurate recapitulation of the injury is needed to better study the injury progression, as well as screen for novel therapies. This research combines an existing model of compartment syndrome with its clinical standard of care (fasciotomy), creating a more accurate rat model of injury, and providing for a better treatment screening tool. These results show how our model leads to a sustained skeletal muscle deficit with increased inflammation.

A Clinician’s Guide for Treating Active Military and Veteran Populations With EMDR Therapy

A Clinician’s Guide for Treating Active Military and Veteran Populations With EMDR Therapy

Secondary Qualitative Analysis of Moral Injury in Obstetric and Neonatal Nurses

ObjectiveTo investigate the presence of symptoms of moral injury in obstetric and neonatal nurses. DesignA secondary qualitative analysis using an analytic expansion of three primary studies. SettingPostal mail and electronic surveys. ParticipantsI used three primary studies: participants in the first consisted of 78 labor and delivery nurses, participants in the second consisted of 75 nurse-midwives, and participants in the third consisted of 22 NICU nurses. MethodsI used Krippendorff’s content analysis method for qualitative data to reanalyze the three primary data sets. The categories I used in this analysis were the 10 symptoms of moral injury that are assessed by the Moral Injury Symptoms Scale–Health Professionals Version. ResultsWhen combining the three types of obstetric and neonatal participants, the top three most frequently cited symptoms of moral injury were moral concern, guilt, and self-condemnation. For participants in labor and delivery units and NICUs, moral concern was the most often described symptom, whereas for participants in midwifery it was guilt. None of the participants reported loss of meaning in their lives, loss of faith, or religious struggle. Participants who worked in NICUs did not describe any symptoms of shame or difficulty forgiving. ConclusionIn addition to the primary symptoms of moral injury, reported secondary consequences of moral injury can include depression, anxiety, anger, self-harm, and social problems. Interventions such as acceptance and commitment therapy are needed to help nurses address the potential for moral injury and repair its effects. Since the COVID-19 pandemic, now more than ever, moral injury needs to be recognized in obstetric and neonatal nurses and not just in the military population.

Adverse childhood experiences, military adversities, and adult health outcomes among female Veterans in the UK

LAY SUMMARY Adverse childhood experiences (ACEs) are highly stressful events or situations that occur in childhood and adolescence. Childhood adversities can lead to several negative outcomes in adulthood, including poor physical and mental health. Military populations often report a high number of childhood adversities. Research on ACEs that focuses specifically on female Veterans is lacking. The current study explored the relationships among ACEs, military adversities, and adult health outcomes in female army Veterans in the United Kingdom. In total, 750 female army Veterans completed an online survey containing questions about childhood experiences and military adversities, as well as physical and mental health in adulthood. A large percentage of female army Veterans reported at least one ACE, including emotional and physical abuse. Experience of childhood adversities was most strongly linked to experiencing symptoms of posttraumatic stress disorder in adulthood and experiences of emotional bullying, sexual harassment, and assault during military service.

Factors Associated with Human Papillomavirus Vaccine Initiation and Compliance Among U.S. Military Service Members.

The primary objective of the current study was to assess factors associated with Human Papillomavirus (HPV) vaccine initiation and compliance in a cohort of active duty US military service members (SM). We included active-duty participants aged 18-26 years from the Millennium Cohort Study, a longitudinal cohort study of over 200,000 military SMs. The eligible study population included 22,387 female SMs and 31,705 male SMs. Vaccination was assessed over the period 2006-2017. Logistic regression was used to estimate the odds of vaccine initiation and compliance (3 doses within a 1-year period) in relation to demographic, military, health, and behavioral characteristics. Among female SMs, 37.8% initiated the vaccine and 40.2% of initiators completed the series within a year. Among male SMs, 3.9% initiated the vaccine and 22.1% of initiators completed the series within a year. Differences by sociodemographic factors, deployment status, branch of service, occupation, and smoking status-but not by selected mental health conditions-were observed. HPV vaccination uptake is subpar across all military service branches. Certain subgroups of SMs could be targeted to increase overall HPV vaccine coverage in the US military population.

Post-Admission Cognitive Therapy for a Transgender Service Member With a Recent Suicidal Crisis: A Case Study of Gender-Affirming Care

While elevated suicide risk in the American military and veteran population has led to the development of targeted interventions, the increased risk of suicidal ideation and behavior among transgender and gender diverse (TGD) Service members requires that interventions address suicide risk within the context of minority stressors and gender-affirming care. This case study presents Jordan (an alias), a transgender Service member who received inpatient psychiatric treatment following a suicide attempt precipitated by distress relating to gender dysphoria, minority status, and associated stressors. Jordan completed Post-Admission Cognitive Therapy (PACT; Ghahramanlou-Holloway, Cox, & Greene, 2012), a cognitive-behavioral intervention targeting suicide risk among military personnel and dependents psychiatrically hospitalized following a suicidal crisis. Within the context of PACT, Jordan’s treatment included identifying and addressing distress related to minority stressors (externalized stigma, internalized transphobia, anticipated rejection, gender concealment) using gender-affirming best practices. Marked changes in Jordan's self-report measures from baseline to follow-up, as well as qualitative changes reported by Jordan, demonstrate that she felt comfortable, safe, and ready to be discharged from the inpatient unit after completing PACT treatment and gaining exposure to the skills necessary to help prevent and/or manage future suicidal crises. Treatment implications and recommendations for addressing suicide risk within the context of gender-affirming care and prevalent minority stressors are discussed.

Wingman-Connect Program increases social integration for Air Force personnel at elevated suicide risk: Social network analysis of a cluster RCT

U.S. military suicides are increasing and disrupted relationships frequently precede them. Group-level interventions are needed that reduce future suicide vulnerability among healthy members and also ameliorate risk among those already suicidal. We examined whether our Wingman-Connect Program (W-CP) strengthened Air Force relationship networks and socially integrated at-risk members. Air Force personnel classes in training were randomized to W-CP or active control (cluster RCT), followed up at 1 and 6 months (94% and 84% retention). Data were collected in 2017–2019 and analyzed in 2020–2021. Participants were 1485 male and female Airmen in 215 technical training classes. W-CP training involved strengthening group bonds, skills for managing career and personal stressors, and diffusion of healthy norms. Active control was stress management training. Primary outcomes were social network metrics based on Airmen nominations of valued classmates after 1 month. Baseline CAT-SS >34 defined elevated suicide risk. W-CP increased social network integration, with largest impact for Airmen already at elevated suicide risk (n = 114, 7.7%). For elevated risk Airmen, W-CP improved all network integration metrics, including 53% average gain in valued connection nominations received from other Airmen (RR = 1.53, 95% CI = 1.12, 2.08) and eliminated isolation. No elevated risk Airmen in W-CP were isolates with no valued connections after 1-month vs. 10% among controls (P < .035). In contrast to at-risk controls, at-risk W-CP Airmen increased connections after intervention. W-CP's effect on a key indicator, ≥2 connections, was still greater 2–4 months after classes disbanded (6-months). Wingman-Connect Program built enhanced suicide protection into unit relationship networks and counteracted standard drift towards disconnection for at-risk Airmen, despite no explicit content targeting connections specifically to at-risk Airmen. Findings support a growing case for the unique contribution of group-level interventions to improve social health of broader military populations while also ameliorating risk among individuals already at elevated suicide risk.

The seroepidemiology of dengue in a US military population based in Puerto Rico during the early phase of the Zika pandemic.

Understanding the burden and risk factors of dengue virus (DENV) infection in Puerto Rico is important for the prevention of dengue in local, traveler and military populations. Using sera from the Department of Defense Serum Repository, we estimated the prevalence and predictors of DENV seropositivity in those who had served in Puerto Rico, stratified by birth or prior residence (“birth/residence”) in dengue-endemic versus non-endemic regions. We selected sera collected in early 2015 from 500 U.S. military members, a time-point also permitting detection of early cryptic Zika virus (ZIKV) circulation. 87.2% were born or resided in a DENV-endemic area before their military service in Puerto Rico. A high-throughput, flow-cytometry-based neutralization assay was employed to screen sera for ZIKV and DENV neutralizing antibodies, and confirmatory testing was done by plaque-reduction neutralization test (PRNT). We identified one Puerto Rico resident who seroconverted to ZIKV by June 2015, suggesting cryptic ZIKV circulation in Puerto Rico at least 4 months before the first reported cases. A further six PRNT-positive presumptive ZIKV infections which were resolved as DENV infections only by the use of paired sera. We noted 66.8% of the total study sample was DENV seropositive by early 2015. Logistic regression analysis indicated that birth/residence in a dengue non-endemic region (before military service in Puerto Rico) was associated with a lower odds of DENV exposure by January—June 2015 (aOR = 0.28, p = 0.001). Among those with birth/residence in a non-endemic country, we noted moderate evidence to support increase in odds of DENV exposure for each year of military service in Puerto Rico (aOR = 1.58, p = 0.06), but no association with age. In those with birth/residence in dengue-endemic regions (before military service in Puerto Rico), we noted that age (aOR = 1.04, p = 0.02), rather than duration of Puerto Rico service, was associated with dengue seropositivity, suggesting earlier lifetime DENV exposure. Our findings provide insights into the burden and predictors of DENV infection in local, traveler and military populations in Puerto Rico. Our study also highlights substantial PRNT ZIKV false-positivity when paired sera are not available, even during periods of very low ZIKV prevalence.

New Training Program for the New Requirements of Combat of Tactical Athletes

Actual theaters of operations are complex contexts where soldiers must face different situations, such as symmetrical, asymmetrical, or close quarter combat. The requirements of the actual battlefield are different to the traditional conditioning military training. This new changing scenario produces an activation of the innate fight or flight defense mechanisms with large activations of the anaerobic metabolic pathways and the sympathetic autonomic nervous system. In these scenarios, the anaerobic, aerobic, and strength demands are so specific and the time to improve all training demands in the units is limited. We propose a new training periodization for the military population based on the latest research into the psychophysiological response of soldiers in actual theaters of operations (actual military missions) and actual civilian models of training and periodization to develop a specific, easy, and reliable periodization model for actual tactical athletes. This training intervention was developed in order to improve operational training according to the demands of actual theaters of operations, based on recent research in military and civilian populations. We tried to conduct a proposal that is easy to apply, with minimal use of material different to what could be found in a military base and that could be implemented in a short period of time.

The Impacts of Noise Exposure on the Middle Ear Muscle Reflex in a Veteran Population.

Human studies of noise-induced cochlear synaptopathy using physiological indicators identified in animal models (auditory brainstem response [ABR] Wave I amplitude, envelope following response [EFR], and middle ear muscle reflex [MEMR]) have yielded mixed findings. Differences in the population studied may have contributed to the differing results. For example, due to differences in the intensity level of the noise exposure, noise-induced synaptopathy may be easier to detect in a military Veteran population than in populations with recreational noise exposure. We previously demonstrated a reduction in ABR Wave I amplitude and EFR magnitude for young Veterans with normal audiograms reporting high levels of noise exposure compared to non-Veteran controls. In this article, we expand on the previous analysis in the same population to determine if MEMR magnitude is similarly reduced. Contralateral MEMR growth functions were obtained in 92 young Veterans and non-Veterans with normal audiograms, and the relationship between noise exposure history and MEMR magnitude was assessed. Associations between MEMR magnitude and distortion product otoacoustic emission, EFR, and ABR measurements collected in the same sample were also evaluated. The results of the statistical analysis, although not conventionally statistically significant, suggest a reduction in mean MEMR magnitude for Veterans reporting high noise exposure compared with non-Veteran controls. In addition, the MEMR appears relatively insensitive to subclinical outer hair cell dysfunction, as measured by distortion product otoacoustic emissions, and is not well correlated with ABR and EFR measurements. When combined with our previous ABR and EFR findings in the same population, these results suggest that noise-induced synaptopathy occurs in humans. In addition, the findings indicate that the MEMR may be a good candidate for noninvasive diagnosis of cochlear synaptopathy/deafferentation and that the MEMR may reflect the integrity of different neural populations than the ABR and EFR. https://doi.org/10.23641/asha.18665645.