Getting on the Same Page: Consolidating Terminology to Facilitate Cross-Disciplinary Health-Related Blast Research.

The consequences of blast exposure (including both high-level and low-level blast) have been a focal point of military interest and research for years. Recent mandates from Congress (e.g., National Defense Authorization Act for Fiscal Year 2018, section 734) have further accelerated these efforts, facilitating collaborations between research teams from a variety of disciplinary backgrounds. Based on findings from a recent scoping review, we argue that the scientific field of blast research is plagued by inconsistencies in both conceptualization of relevant constructs and terminology used to describe them. These issues hamper our ability to interpret study methods and findings, hinder efforts to integrate findings across studies to reach scientific consensus, and increase the likelihood of redundant efforts. We argue that multidisciplinary experts in this field require a universal language and clear, standardized terminology to further advance the important work of examining the effects of blast exposure on human health, performance, and well-being. To this end, we present a summary of descriptive conventions regarding the language scientists currently use when discussing blast-related exposures and outcomes based on findings from a recent scoping review. We then provide prescriptive conventions about how these terms should be used by clearly conceptualizing and explicitly defining relevant constructs. Specifically, we summarize essential concepts relevant to the study of blast, precisely distinguish between high-level blast and low-level blast, and discuss how the terms acute, chronic, exposure, and outcome should be used when referring to the health-related consequences of blast exposure.

The Persistence of Blast- Versus Impact-Induced Concussion Symptomology Following Deployment.

OBJECTIVE: To examine the persistence of concussion-related symptoms following injury as a function of mechanism of injury (high-level blast [HLB] vs impact) and low-level blast (LLB) exposure among Marines. SETTING: Upon return from deployment and approximately 6 months later, respectively, Marines completed the Post-Deployment Health Assessment and Post-Deployment Health Re-Assessment in an operational or clinic setting. PARTICIPANTS: Data from active duty enlisted Marines who completed both assessments (n = 102 075) and who reported a potentially mild traumatic brain injury (mTBI)-inducing event and completed an mTBI screen (n = 8106) were analyzed. DESIGN: This was a retrospective cohort study of Marines deployed between 2008 and 2012. Marines were categorized into groups with relatively high versus low risk for occupational risk of LLB exposure. A mixed model analysis of variance was used to examine the number of symptoms Marines reported experiencing during deployment as a function of probable concussion, HLB exposure, occupational risk, type of symptom, and time of measurement. MAIN MEASURES: Self-reported deployment exposures including HLB, probable mTBIs, and occupational risk of LLB exposure were identified. Outcomes included the proportion of neurological, musculoskeletal, and immunological symptoms for which Marines reported seeking care during and following deployment were analyzed. RESULTS: Probable HLB-induced mTBIs (vs impact-induced) were associated with significantly more neurological symptoms at return from deployment and approximately 6 months later. Although symptom reporting decreased at statistically equivalent rates regardless of mechanism of injury, those with a probable HLB-induced concussion continued to report elevated symptomology post-deployment. Additionally, Marines with probable concussion working in occupations with LLB exposure reported elevated levels of persistent neurological symptoms. Both HLB and LLB exposure were associated with neurological symptoms that persisted following deployment. CONCLUSION: These findings suggest that blast-induced brain injuries may be fundamentally different from impact-induced injuries, and that additional screening and symptomatic treatment for blast-exposed patients may be warranted.

Potential Health and Performance Effects of High-Level and Low-Level Blast: A Scoping Review of Two Decades of Research.

Although blast exposure has been recognized as a significant source of morbidity and mortality in military populations, our understanding of the effects of blast exposure, particularly low-level blast (LLB) exposure, on health outcomes remains limited. This scoping review provides a comprehensive, accessible review of the peer-reviewed literature that has been published on blast exposure over the past two decades, with specific emphasis on LLB. We conducted a comprehensive scoping review of the scientific literature published between January 2000 and 2019 pertaining to the effects of blast injury and/or exposure on human and animal health. A three-level review process with specific inclusion and exclusion criteria was used. A full-text review of all articles pertaining to LLB exposure was conducted and relevant study characteristics were extracted. The research team identified 3,215 blast-relevant articles, approximately half of which (55.4%) studied live humans, 16% studied animals, and the remainder were non-subjects research (e.g., literature reviews). Nearly all (99.49%) of the included studies were conducted by experts in medicine or epidemiology; approximately half of these articles were categorized into more than one medical specialty. Among the 51 articles identified as pertaining to LLB specifically, 45.1% were conducted on animals and 39.2% focused on human subjects. Animal studies of LLB predominately used shock tubes to induce various blast exposures in rats, assessed a variety of outcomes, and clearly demonstrated that LLB exposure is associated with brain injury. In contrast, the majority of LLB studies on humans were conducted among military and law enforcement personnel in training environments and had remarkable variability in the exposures and outcomes assessed. While findings suggest that there is the potential for LLB to harm human populations, findings are mixed and more research is needed. Although it is clear that more research is needed on this rapidly growing topic, this review highlights the detrimental effects of LLB on the health of both animals and humans. Future research would benefit from multidisciplinary collaboration, larger sample sizes, and standardization of terminology, exposures, and outcomes.

Self-Reported Concussion Symptomology during Deployment: Differences as a Function of Injury Mechanism and Low-Level Blast Exposure.

Traumatic brain injury (TBI), which can result from either direct impact to the head or blast exposure, has been the leading cause of morbidity and mortality in recent military conflicts. However, little research has compared mTBIs by mechanism of injury. The present research addressed two research questions: (1) Are blast-related mTBIs (mbTBIs) associated with significantly more symptoms than impact-related mTBIs (miTBIs), and (2) are mTBIs associated with more self-reported symptoms among service members with higher (vs. lower) risk of low-level blast (LLB) exposure. We obtained data from 181,423 active duty enlisted United States Marines deployed between 2003 and 2012, who completed the Post-Deployment Health Assessment. We examined the self-reported symptoms of Marines who completed an mTBI screen and could be classified as at high or low risk for LLB exposure, using their military occupation as a proxy (n = 12,013). Symptoms were compared as a function of blast exposure (blast vs. impact), probable mTBI (yes vs. no), occupational risk of LLB (high vs. low), and symptom type (neurological vs. musculoskeletal vs. immunological). Overall, musculoskeletal symptoms were reported more frequently than neurological and immunological symptoms. However, Marines with probable mTBIs (regardless of mechanism of injury) and those with probable mbTBIs specifically reported more neurological symptoms, which rose to the level of musculoskeletal symptom reporting. Among Marines with probable mTBI, those with high risk of LLB exposure also reported significantly more neurological symptoms. Our results indicate that mbTBIs and miTBIs may be fundamentally different, and that LLB may increase susceptibility to injury.

Blast Exposure and Risk of Recurrent Occupational Overpressure Exposure Predict Deployment TBIs.

INTRODUCTION: Traumatic brain injury (TBI) has been the leading cause of morbidity and mortality in recent military conflicts and deployment-related TBIs are most commonly caused by blast. However, knowledge of risk factors that increase susceptibility to TBI following an acute, high-level blast is limited. We hypothesized that recurrent occupational overpressure exposure (ROPE) may be one factor that increases susceptibility to mild TBI (mTBI) following blast. MATERIALS AND METHODS: Using military occupational specialty as a proxy, we examined the effects of high versus low ROPE on mTBI following blast exposure. Initial analyses included 111,641 active-duty-enlisted U.S. Marines who completed the 2003 or 2008 version of the Post-Deployment Health Assessment. Final analyses examined probable mTBI screens among Marines with at least one qualifying exposure as a function of whether the exposure was a blast and level of ROPE (N = 12,929). This study was approved by the Institutional Review Board at the Naval Health Research Center. RESULTS: Blast and ROPE were both independently and jointly associated with a probable mTBI. Marines who experienced a blast (vs other qualifying exposure) and those in high (vs low) risk occupations were 1.07 and 1.23 times more likely to sustain a probable mTBI, respectively. Furthermore, among those who experienced a blast during deployment, those in high-risk occupations were 1.45 times more likely than those in low-risk occupations to sustain a probable mTBI. CONCLUSIONS: Blast exposure and ROPE were independently associated with mTBIs, and Marines with both blast exposure during deployment and ROPE were especially likely to sustain an mTBI. This suggests that ROPE heightens the risk of mTBI following blast. Ongoing research is examining the severity, symptomology, and sequelae of TBIs as a function of ROPE.

"We Want to Build a Network": Professional Experiences of Case Managers Working With Military Families.

Optimizing case management (CM) services increases service member readiness at home and abroad. However, little research has been conducted on the experiences of case managers providing services to military families within the Military Health System. Semistructured qualitative interviews were conducted to explore the professional experiences of case managers to identify factors that may affect care to military families. A total of 53 case managers from military medical treatment facilities (MTFs) varying in size, location, and branch of service were interviewed by telephone to explore their perspectives. Qualitative content analysis was performed. Case managers serve a variety of functions, but specific roles vary between MTFs. Factors that affect CM services for military families were identified: (1) need for pediatric specialization, (2) heavy workload, (3) appropriate staff, (4) patient handoffs, and (5) the role of CM. Recommendations for improving CM services to facilitate the well-being of military families are discussed.

Trajectories of adolescent mother-grandmother psychological conflict during early parenting and children's problem behaviors at age 7.

This study extends the determinants of parenting model to adolescent mothers by examining how adolescent mother-grandmother psychological conflict and perceptions of infant fussiness from birth through age 2 years relate to children's problem behaviors at age 7. Participants were 181 adolescent mother, child, and grandmother triads living in multigenerational households and recruited at delivery. Psychological conflict was characterized by two stable trajectories. In multivariate models that included maternal depression, both psychological conflict and perceptions of infant fussiness predicted externalizing behavior at age 7. Perceptions of infant fussiness, but not psychological conflict, predicted internalizing behavior at age 7.