Pre-Existing Audiometric Hearing Loss is a Predictor of Significant Threshold Shift Following Injury During Combat Deployment.

OBJECTIVES: Military personnel are exposed to multiple risk factors for hearing loss, particularly on the battlefield. The objective of this study was to determine whether pre-existing hearing loss predicted hearing threshold shift in male U.S. military personnel following injury during combat deployment. DESIGN: This was a retrospective cohort study with 1573 male military personnel physically injured in Operations Enduring and Iraqi Freedom between 2004 and 2012. Audiograms before and after injury were analyzed and used to calculate significant threshold shift (STS), defined as a 30 dB or greater change in the sum of hearing thresholds at 2000, 3000, and 4000 Hz in either ear on the postinjury audiogram, relative to the same frequencies on the preinjury audiogram. RESULTS: Twenty-five percent (n = 388) of the sample had preinjury hearing loss, which mostly occurred in the higher frequencies (i.e., 4000 and 6000 Hz). The prevalence of postinjury STS ranged from 11.7% to 33.3% as preinjury hearing level moved from better to worse. In multivariable logistic regression, preinjury hearing loss was a predictor of STS, and there was a dose-response relationship between severity of preinjury hearing threshold and postinjury STS, specifically for preinjury hearing levels of 40 to 45 dBHL (odds ratio [OR] = 1.99; 95% confidence interval [CI] = 1.03 to 3.88), 50 to 55 dBHL (OR = 2.33; 95% CI = 1.17 to 4.64), and >55 dBHL (OR = 3.77; 95% CI = 2.25 to 6.34). CONCLUSIONS: These findings suggest that better preinjury hearing provides increased resistance to threshold shift than impaired preinjury hearing. Although STS is calculated using 2000 to 4000 Hz, clinicians must closely attend to the pure-tone response at 6000 Hz and use this test frequency to identify service members at-risk for STS prior to combat deployment.

Relationship Between Tinnitus and Hearing Outcomes Among US Military Personnel After Blast Injury.

OBJECTIVES: To examine the association between tinnitus and hearing outcomes among US military personnel after blast injury, including any hearing loss, low-frequency hearing loss, high-frequency hearing loss, early warning shift, and significant threshold shift. DESIGN: In this retrospective study, the Blast-Related Auditory Injury Database was queried for male military service members who had audiometric data 2 years before and after blast injury between 2004 and 2012 with no history of hearing loss or tinnitus before injury (n = 1693). Tinnitus was defined by diagnostic codes in electronic health records. Multivariable logistic regression examined the association between tinnitus and hearing outcomes, while adjusting for covariates. RESULTS: Overall, 14.2% (n = 241) of the study sample was diagnosed with tinnitus within 2 years after blast injury. The proportions of all examined hearing outcomes were higher among service members with tinnitus than those without ( p < 0.001). In multivariable analysis, service members with tinnitus had higher adjusted odds of any hearing loss (odds ratio [OR] = 1.72, 95% confidence interval [CI] = 1.20-2.47), low-frequency hearing loss (OR = 2.77, 95% CI = 1.80-4.26), high-frequency hearing loss (OR = 2.15, 95% CI = 1.47-3.16), early warning shift (OR = 1.83, 95% CI = 1.36-2.45), and significant threshold shift (OR = 2.15, 95% CI = 1.60-2.89) compared with service members without tinnitus. CONCLUSIONS: The findings of this study demonstrate that tinnitus diagnosed within 2 years after blast injury is associated with the examined hearing outcomes in US military personnel. Service members with blast injury who subsequently experience tinnitus should receive routine audiometric hearing conservation testing and be carefully examined for poor hearing outcomes by an audiologist.

Deployment-related concussion and long-term health-related quality of life among US military personnel.

PURPOSE: To examine the relationship between deployment-related concussion and long-term health-related quality of life (HRQoL) among injured US military personnel. METHODS: The study sample included 810 service members with deployment-related injuries between 2008 and 2012 who responded to a web-based longitudinal health survey. Participants were categorized into three injury groups: concussion with loss of consciousness (LOC; n = 247), concussion without LOC (n = 317), or no concussion (n = 246). HRQoL was measured using the 36-Item Short Form Health Survey physical and mental component summary (PCS and MCS) scores. Current post-traumatic stress disorder (PTSD) and depression symptoms were examined. Multivariable linear regression models assessed the effects of concussion on PCS and MCS scores, while controlling for covariates. RESULTS: A lower PCS score was observed in participants with concussion with LOC (B = - 2.65, p = 0.003) compared with those with no history of concussion. Symptoms of PTSD (PCS: B = - 4.84, p < 0.001; MCS: B = - 10.53, p < 0.001) and depression (PCS: B = - 2.85, p < 0.001; MCS: B = - 10.24, p < 0.001) were the strongest statistically significant predictors of lower HRQoL. CONCLUSION: Concussion with LOC was significantly associated with lower HRQoL in the physical domain. These findings affirm that concussion management should integrate physical and psychological care to improve long-term HRQoL and warrant a more detailed examination of causal and mediating mechanisms. Future research should continue to incorporate patient-reported outcomes and long-term follow-up of military service members to further define the lifelong impact of deployment-related concussion.

Research Letter: Prevalence of Spine Injuries Among US Military Personnel With Combat-Related Concussion.

OBJECTIVE: To describe the prevalence of spine injuries among US service members with combat-related concussion. DESIGN AND PARTICIPANTS: A retrospective review of medical records for US service members injured during combat operations in Iraq and Afghanistan between 2002 and 2020. The study sample included 27 897 service members categorized into 3 groups: concussion with loss of consciousness (LOC, n = 4631), concussion non-LOC ( n = 5533), and non-concussion ( n = 17 333). MAIN MEASURES: Spine injuries were identified by International Classification of Diseases, Ninth Revision, Clinical Modification ( ICD-9-CM ) codes and classified by body region and nature of injury using the Barell injury diagnosis matrix. Differences in prevalence of spine injuries by concussion group were evaluated using χ 2 tests. RESULTS: Spine injuries were most prevalent among service members with concussion LOC (31.1%), followed by concussion non-LOC (18.3%), and non-concussion (10.0%, P < .001). Sprains and strains were the most prevalent spine injury category, with injuries to the cervical, thoracic, and lumbar regions significantly more prevalent in the concussion groups ( P values < .001), particularly individuals with LOC compared with non-concussion. CONCLUSION: The US military personnel with combat-related concussion, especially individuals with LOC, may also have spine injuries. Routine assessment for spine injury is recommended during concussion screening because this may impact clinical management and rehabilitation.

Postinjury Care and Complications Among U.S. Military Women With Combat-Related Major Limb Traumatic Amputation.

BACKGROUND: U.S. servicewomen may be at greater risk of injury in future conflicts as they integrate into combat occupations. More than 1,000 servicewomen were wounded during military conflicts in Iraq and Afghanistan. Some women sustained traumatic amputations, and research on their postinjury health is needed. OBJECTIVE: To describe acute care, complications, and health care utilization among servicewomen with combat-related amputations, comparing them with injured men. METHODS: In this retrospective matched-pairs study, women were identified from the Expeditionary Medical Encounter Database between 2003 and 2012 and matched with men on amputation injuries, injury severity, and age. Differences were assessed with nonparametric tests for paired data. RESULTS: Of 20 women identified for analysis, 13 received tourniquets, three were administered procoagulants, and six had massive transfusions. Women averaged 3.4 (SD = 1.6) postinjury complications, and the most frequent were heterotopic ossification (n = 17), posthemorrhagic anemias (n = 13), and bacterial wound infections (n = 10). Acute care and complications were similar among men. Women averaged more acute care days (M = 49.8, SD = 30.6) than men (M = 46.1, SD = 27.4) but fewer intensive care unit days (women: M = 2.6, SD = 4.0; men: M = 4.4, SD = 8.3). No statistical differences were observed. CONCLUSION: Postinjury care among servicewomen with combat-related amputations was comparable with servicemen, and complications were common. This information can aid providers and nursing staff in the management of these injuries.

Symptom profiles following combat injury and long-term quality of life: a latent class analysis.

PURPOSE: The purpose of this study was to identify symptom profiles among U.S. military personnel within 1 year after combat injury and assess the relationship between the symptom profiles and long-term quality of life (QoL). METHODS: The study sample consisted of 885 military personnel from the Expeditionary Medical Encounter Database who completed (1) a Post-Deployment Health Assessment (PDHA) within 1 year following combat injury in Iraq or Afghanistan, and (2) a survey for the Wounded Warrior Recovery Project (WWRP), a longitudinal study tracking patient-reported outcomes (e.g., QoL) in injured military personnel. Fifteen self-reported symptoms from the PDHA were assessed using latent class analysis to develop symptom profiles. Multivariable linear regression assessed the predictive effect of symptom profiles on QoL using the physical (PCS) and mental (MCS) component summary scores from the 36-Item Short Form Survey included in the WWRP. Time between PDHA and WWRP survey ranged from 4.3 to 10.5 years (M = 6.6, SD = 1.3). RESULTS: Five distinct symptom profiles were identified: low morbidity (50.4%), multimorbidity (15.6%), musculoskeletal (14.0%), psycho-cognitive (11.1%), and auditory (8.9%). Relative to low morbidity, the multimorbidity (ß = - 5.45, p < 0.001) and musculoskeletal (ß = - 4.23, p < 0.001) profiles were associated with lower PCS, while the multimorbidity (ß = - 4.25, p = 0.002) and psycho-cognitive (ß = - 3.02, p = 0.042) profiles were associated with lower MCS. CONCLUSION: Multimorbidity, musculoskeletal, and psycho-cognitive symptom profiles were the strongest predictors of lower QoL. These profiles can be employed during screening to identify at-risk service members and assist with long-term clinical planning, while factoring in patient-specific impairments and preferences.

Co-occurrence of hearing loss and posttraumatic stress disorder among injured military personnel: a retrospective study.

BACKGROUND: Posttraumatic stress disorder (PTSD) and hearing loss are hallmark public health issues related to military service in Iraq and Afghanistan. Although both are significant individual contributors to disability among veterans, their co-occurrence has not been specifically explored. METHODS: A total of 1179 male U.S. military personnel who sustained an injury between 2004 and 2012 during operations in Iraq or Afghanistan were identified from clinical records. Pre- and postinjury audiometric data were used to define new-onset hearing loss, which was categorized as unilateral or bilateral. Diagnosed PTSD was abstracted from electronic medical records. Logistic regression analysis examined the relationship between hearing loss and PTSD, while adjusting for age, year of injury, occupation, injury severity, injury mechanism, and presence of concussion. RESULTS: The majority of the study sample were aged 18-25 years (79.9%) and sustained mild-moderate injuries (94.6%). New-onset hearing loss was present in 14.4% of casualties (10.3% unilateral, 4.1% bilateral). Rates of diagnosed PTSD were 9.1, 13.9, and 29.2% for those with no hearing loss, unilateral hearing loss, and bilateral hearing loss, respectively. After adjusting for covariates, those with bilateral hearing loss had nearly three-times higher odds of PTSD (odds ratio = 2.92; 95% CI, 1.47-5.81) compared to those with no hearing loss. Unilateral hearing loss was not associated with PTSD. CONCLUSIONS: Both PTSD and hearing loss are frequent consequences of modern warfare that adversely affect the overall health of the military. Bilateral, but not unilateral, hearing loss was associated with a greater burden of PTSD. This has implications for warfighter rehabilitation and should encourage collaboration between audiology and mental health professionals.

Multimorbidity and quality of life after blast-related injury among US military personnel: a cluster analysis of retrospective data.

BACKGROUND: Blast injury emerged as a primary source of morbidity among US military personnel during the recent conflicts in Iraq and Afghanistan, and led to an array of adverse health outcomes. Multimorbidity, or the presence of two or more medical conditions in an individual, can complicate treatment strategies. To date, there is minimal research on the impact of multimorbidity on long-term patient-reported outcomes. We aimed to define multimorbidity patterns in a population of blast-injured military personnel, and to examine these patterns in relation to long-term quality of life (QOL). METHODS: A total of 1972 US military personnel who sustained a blast-related injury during military operations in Iraq and Afghanistan were identified from clinical records. Electronic health databases were used to identify medical diagnoses within the first year postinjury, and QOL was measured with a web-based assessment. Hierarchical cluster analysis methods using Ward's minimum variance were employed to identify clusters with related medical diagnosis categories. Duncan's multiple range test was used to group clusters into domains by QOL. RESULTS: Five distinct clusters were identified and grouped into three QOL domains. The lowest QOL domain contained one cluster with a clinical triad reflecting musculoskeletal pain, concussion, and mental health morbidity. The middle QOL domain had two clusters, one with concussion/anxiety predominating and the other with polytrauma. The highest QOL domain had two clusters with little multimorbidity aside from musculoskeletal pain. CONCLUSIONS: The present study described blast-related injury profiles with varying QOL levels that may indicate the need for integrated health services. Implications exist for current multidisciplinary care of wounded active duty and veteran service members, and future research should determine whether multimorbidity denotes distinct post-blast injury syndromes.

Clinical audiometric patterns of hearing loss following blast-related injury in U.S. military personnel.

Objective: To identify clinical audiometric patterns of hearing loss following blast-related injury (BRI) in US military personnel.Design: Retrospective cohort study.Study sample: A total of 1186 male Navy and Marine Corps service members with normal hearing thresholds on pre-injury audiograms who had post-injury audiograms in the Blast-Related Auditory Injury Database.Results: Low- and high-frequency pure-tone averages (PTAs) were significantly higher in those with BRI than non-blast-related injury (NBRI) for both ears (p < 0.001 for all comparisons). Overall, 172 (15%) service members met criteria for post-injury hearing loss and were categorised into PTA or single-frequency hearing loss subgroups. PTA hearing loss was more common in the BRI group (50% vs. 33%, p < 0.036), whereas single-frequency hearing loss was more common in the NBRI group. Most hearing loss was mild to moderate in degree, and three distinct audiometric patterns emerged (i.e. flat, sloping and rising). A flat pattern was the most prevalent configuration among those with PTA hearing loss, especially bilateral loss. Single-frequency hearing loss was mostly unilateral and high frequency.Conclusions: In this study, BRI produced hearing loss across test frequencies, generating more clinically actionable post-injury audiograms than NBRI. We found that post-injury audiometric patterns of hearing loss among military personnel may vary.

Preliminary study of hearing protection and non-impact, blast-induced concussion in US military personnel.

PRIMARY OBJECTIVE: To examine the relationship between hearing protection and non-impact, blast-induced concussion in US military personnel. RESEARCH DESIGN: Retrospective cohort study. METHODS AND PROCEDURES: A total of 501 US service members from the Expeditionary Medical Encounter Database with hearing protection status reported either 'worn' or 'not worn' were eligible for analysis. Clinical records were reviewed for concussion diagnoses. Univariate and multiple logistic regressions were performed. MAIN OUTCOMES AND RESULTS: Overall, 270 (53.9%) service members sustained non-impact, blast-induced concussion and 231 (46.1%) sustained other blast injuries. Only 39.6% (107 of 270) of service members with concussion wore hearing protection at the point of injury compared with 61.0% (141 of 231) of those with other injuries (p < 0.001). After adjusting for covariates, service members wearing hearing protection had significantly lower odds of concussion compared with those not wearing hearing protection (odds ratio = 0.42, 95% confidence interval = 0.29-0.62). CONCLUSIONS: To our knowledge, this preliminary study is the first to demonstrate that hearing protection is associated with lower odds of non-impact, blast-induced concussion. The benefits of using hearing protection in terms of force readiness could be significant since many service members wounded in recent conflicts were diagnosed with concussion.

Sex Differences in Screening Positive for Post-Traumatic Stress Disorder After Combat Injury.

INTRODUCTION: U.S. military women were at risk of combat exposure and injury from asymmetric warfare during the conflicts in Iraq and Afghanistan. Previous research has yielded mixed results when examining sex differences in PTSD following operational deployment. To date, no study has explored sex differences in PTSD after combat injury. MATERIALS AND METHODS: This retrospective study included U.S. military service men and women who experienced a combat injury in Iraq or Afghanistan (March 2003 to March 2013) and completed a Post-Deployment Health Assessment (PDHA) within 1 year of injury. The PDHA is administered at the end of deployment and includes the 4-item Primary Care PTSD Screen. The prevalence of screening positive for PTSD was evaluated by sex using a chi-square test. Multivariable logistic regression was used to assess the association between sex and PTSD while adjusting for covariates. RESULTS: The study sample included 16,215 injured military personnel (666 women and 15,549 men). The average time between injury and PDHA was 132 days (SD = 91.0). Overall, women had a higher prevalence of screening positive for PTSD than men (48.3% vs. 40.9%, P < .001). In multivariable regression, women had higher odds than men of screening positive for PTSD (odds ratio, 1.34; 95% confidence interval, 1.14-1.57). Psychiatric history was the strongest predictor of screening positive for PTSD regardless of sex (odds ratio, 1.59; 95% confidence interval, 1.45-1.74). CONCLUSIONS: In this novel study of military service members, women were more likely to screen positive for PTSD than men after combat injury. Strategies to mitigate PTSD, enhance resiliency, and incorporate psychological care into injury rehabilitation programs for women may be needed for future U.S. military conflicts where they will play a larger role in combat operations.

Sex Differences in Postinjury Health Profiles Among U.S. Military Personnel Following Deployment-Related Concussion.

Background: Women in the U.S. military are now authorized to serve in direct combat occupations. This may increase their risk of combat injuries, such as concussion, in future conflicts. Knowledge of sex differences in health profiles after concussion is paramount for military medical planning efforts. The purpose of this study was to assess sex-related differences in health profiles among U.S. military personnel following deployment-related concussion. Materials and Methods: We conducted a retrospective study of service members who sustained a concussion during combat deployment between 2004 and 2013. Postinjury diagnoses were abstracted from outpatient encounters in electronic health records for 24 months after concussion. We used hierarchical clustering to identify clusters, termed "health profiles," and logistic regression to determine whether sex predicted membership in the health profiles. Results: The study sample included 346 women and 4536 men with deployment-related concussion. Five postinjury health profiles were identified and classified as no morbidity, back pain, tinnitus/memory loss, posttraumatic stress disorder/postconcussion syndrome, and multimorbidity. Women relative to men had higher odds of membership in the back pain (odds ratio [OR] = 1.32; 95% confidence interval [CI] = 1.05-1.67) and multimorbidity profiles (OR = 1.44; 95% CI = 1.03-2.00) and lower odds than men in the tinnitus/memory loss profile (OR = 0.62; 95% CI = 0.42-0.91). Conclusions: Postinjury health profiles among U.S. service members differ by sex following deployment-related concussion, particularly with a higher burden of multimorbidity among women than men, which may require interdisciplinary care. Women also had higher odds of membership in the back pain profile and lower odds in the tinnitus/memory loss profile than men. To prepare for future military operations where women may have greater exposure to combat, continued research elucidating health-related sex differences after deployment-related concussion is imperative.

Morphine use after combat injury in Iraq and post-traumatic stress disorder.

BACKGROUND: Post-traumatic stress disorder (PTSD) is a common adverse mental health outcome among seriously injured civilians and military personnel who are survivors of trauma. Pharmacotherapy in the aftermath of serious physical injury or exposure to traumatic events may be effective for the secondary prevention of PTSD. METHODS: We identified 696 injured U.S. military personnel without serious traumatic brain injury from the Navy-Marine Corps Combat Trauma Registry Expeditionary Medical Encounter Database. Complete data on medications administered were available for all personnel selected. The diagnosis of PTSD was obtained from the Career History Archival Medical and Personnel System and verified in a review of medical records. RESULTS: Among the 696 patients studied, 243 received a diagnosis of PTSD and 453 did not. The use of morphine during early resuscitation and trauma care was significantly associated with a lower risk of PTSD after injury. Among the patients in whom PTSD developed, 61% received morphine; among those in whom PTSD did not develop, 76% received morphine (odds ratio, 0.47; P<0.001). This association remained significant after adjustment for injury severity, age, mechanism of injury, status with respect to amputation, and selected injury-related clinical factors. CONCLUSIONS: Our findings suggest that the use of morphine during trauma care may reduce the risk of subsequent development of PTSD after serious injury.

Postconcussive symptom reporting among US combat veterans with mild traumatic brain injury from Operation Iraqi Freedom.

OBJECTIVE: To examine the association between postconcussive symptoms and mild traumatic brain injury (MTBI) among combat veterans while adjusting for posttraumatic stress disorder (PTSD) and depression. PATIENTS: Military personnel with provider-diagnosed MTBI (n = 334) or nonhead injury (n = 658) were identified from the Expeditionary Medical Encounter Database. MAIN OUTCOME MEASURES: Post-Deployment Health Assessments and Re-Assessments were used to examine postconcussive symptoms and self-rated health. RESULTS: Personnel with MTBI were more likely to report headache (odds ratio [OR] = 3.37; 95% confidence interval [CI] = 2.19-5.17), back pain (OR = 1.79; 95% CI = 1.23-2.60), memory problems (OR = 1.86; 95% CI = 1.20-2.88), tinnitus (OR = 1.63; 95% CI = 1.10-2.41), and dizziness (OR = 2.13; 95% CI = 1.06-4.29) compared with those with non-head injuries. Among those with MTBI, self-reported decline in health was associated with memory problems (OR = 5.07; 95% CI = 2.56-10.02) and dizziness (OR = 10.60; 95% CI = 3.48-32.27). CONCLUSIONS: Mild traumatic brain injury is associated with reports of negative health consequences among combat veterans even when accounting for co-occurring psychological morbidity. The identification of postconcussive symptoms related to declines in a service member's self-rated health may be important in targeting and prioritizing clinical interventions.

Effect of dwell time on the mental health of US military personnel with multiple combat tours.

OBJECTIVE: We investigated the association of the length of time spent at home between deployments, or dwell time, with posttraumatic stress disorder (PTSD) and other mental health disorders. METHODS: We included US Marine Corps personnel identified from military deployment records who deployed to Operation Iraqi Freedom once (n = 49,328) or twice (n = 16,376). New-onset mental health diagnoses from military medical databases were included. We calculated the ratio of dwell-to-deployment time (DDR) as the length of time between deployments divided by the length of the first deployment. RESULTS: Marines with 2 deployments had higher rates of PTSD than did those with 1 deployment (2.1% versus 1.2%; P < .001). A DDR representing longer dwell times at home relative to first deployment length was associated with reduced odds of PTSD (odds ratio [OR] = 0.47; 95% confidence interval [CI] = 0.32, 0.70), PTSD with other mental health disorder (OR = 0.56; 95% CI = 0.33, 0.94), and other mental health disorders (OR = 0.62; 95% CI = 0.51, 0.75). CONCLUSIONS: Longer dwell times may reduce postdeployment risk of PTSD and other mental health disorders. Future research should focus on the role of dwell time in adverse health outcomes.

Occupational correlates of low back pain among U.S. Marines following combat deployment.

Many U.S. Marines have experienced routine combat deployments during Operation Iraqi Freedom, which present numerous occupational hazards that may result in low back pain (LBP). The objective of this retrospective cohort study was to identify new-onset LBP among Marines following initial deployment to Operation Iraqi Freedom. Active duty Marines deployed to Iraq or Kuwait between 2005 and 2008 were identified from deployment records and linked to medical databases (n = 36,680). The outcome of interest was an International Classification of Diseases, 9th Revision, Clinical Modification code indicating LBP (724.2) within 1 year postdeployment. Multivariate logistic regression examined the effect of occupation on LBP. Overall, 4.1% (n = 1,517) of Marines were diagnosed with LBP. After adjusting for covariates, the service/supply (odds ratio 1.33, 95% confidence interval, 1.12-1.59) and electrical/mechanical/craftsworker occupations (odds ratio 1.31, 95% confidence interval, 1.12-1.53) had higher odds of LBP when compared to the administrative/other referent group. Within these groups, the highest LBP prevalence was in the construction (8.6%) and law enforcement (6.2%) subgroups. Although infantry occupations purposefully engage the enemy and often face sustained physical rigors of combat, LBP was most prevalent in noninfantry occupations. Future studies should include detailed exposure histories to elucidate occupation-specific etiologies of LBP in order to guide prevention efforts.

The Psychological Consequences of Combat Injury Among U.S. Navy Health Care Personnel.

INTRODUCTION: Military health care personnel face numerous risks to mental health, including those associated with combat injury, although no study has described combat injuries within this subgroup or assessed their impact on mental health outcomes. MATERIALS AND METHODS: Male U.S. Navy-enlisted health care personnel, or corpsmen, with combat injury were identified from clinical records. Noninjured corpsmen were matched to injured corpsmen with a 4:1 ratio on year of deployment end or injury and location (Iraq or Afghanistan). The final study population included 2,025 corpsmen (405 injured and 1,620 noninjured). Mental health disorders assessed included posttraumatic stress disorder (PTSD), anxiety, adjustment, mood, and substance abuse disorders. Stratified Cox models were used for analysis while controlling for additional covariates, and injury severity was evaluated as a predictor. RESULTS: Injuries primarily involved the head/neck (73.8%) and extremities (45.7%), and overall injury severity was mostly mild-to-moderate (85.9%). Injured relative to noninjured corpsmen had greater risk of PTSD (risk ratio [RR] 2.45, 95% confidence interval [CI] 2.05 to 2.94), anxiety disorder (RR 1.61, 95% CI 1.32 to 1.96), adjustment disorder (RR 1.88, 95% CI 1.55 to 2.27), mood disorder (RR 1.44, 95% CI 1.16 to 1.79), and substance abuse (RR 1.48, 95% CI 1.14 to 1.91). More severe injuries yielded stronger associations with PTSD (RR 3.57, 95% CI 2.48 to 5.14), anxiety disorder (RR 2.53, 95% CI 1.74 to 3.69), and adjustment disorder (RR 2.17, 95% CI 1.44 to 3.27). CONCLUSIONS: U.S. Navy corpsmen are at risk of combat injury and associated mental health disorders. Injured corpsmen should be screened for mental health problems in the acute phase postinjury, during their remaining time in theater, and after returning home. Future research should address how combat injury compares with other stressors that health care personnel experience and whether the psychological consequences of these injuries (e.g., PTSD) negatively impact work performance and increase risk of burnout.

Combat injury profiles among U.S. military personnel who survived serious wounds in Iraq and Afghanistan: A latent class analysis.

BACKGROUND: The U.S. military conflicts in Iraq and Afghanistan had the most casualties since Vietnam with more than 53,000 wounded in action. Novel injury mechanisms, such as improvised explosive devices, and higher rates of survivability compared with previous wars led to a new pattern of combat injuries. The purpose of the present study was to use latent class analysis (LCA) to identify combat injury profiles among U.S. military personnel who survived serious wounds. METHODS: A total of 5,227 combat casualty events with an Injury Severity Score (ISS) of 9 or greater that occurred in Iraq and Afghanistan from December 2002 to July 2019 were identified from the Expeditionary Medical Encounter Database for analysis. The Barell Injury Diagnosis Matrix was used to classify injuries into binary variables by site and type of injury. LCA was employed to identify injury profiles that accounted for co-occurring injuries. Injury profiles were described and compared by demographic, operational, and injury-specific variables. RESULTS: Seven injury profiles were identified and defined as: (1) open wounds (18.8%), (2) Type 1 traumatic brain injury (TBI)/facial injuries (14.2%), (3) disseminated injuries (6.8%), (4) Type 2 TBI (15.4%), (5) lower extremity injuries (19.8%), (6) burns (7.4%), and (7) chest and/or abdominal injuries (17.7%). Profiles differed by service branch, combat location, year of injury, injury mechanism, combat posture at the time of injury, and ISS. CONCLUSION: LCA identified seven distinct and interpretable injury profiles among U.S. military personnel who survived serious combat injuries in Iraq or Afghanistan. These findings may be of interest to military medical planners as resource needs are evaluated and projected for future conflicts, and medical professionals involved in the rehabilitation of wounded service members.

Sex Differences in the Incidence and Risk of Ankle-Foot Complex Stress Fractures Among U.S. Military Personnel.

Background: The objective of this study was to evaluate sex differences in the incidence and risk of ankle-foot complex (AFC) stress fractures among U.S. military personnel, which could assist in developing management strategies as females assume a greater role in U.S. military operations. Materials and Methods: The Defense Medical Epidemiology Database was used to identify all diagnosed AFC stress fractures in military personnel from 2006 to 2015. Cumulative incidence of AFC stress fractures was calculated and compared by year, service branch, and military rank. Sex differences in the risk of AFC stress fractures by occupation were examined, and integrated (i.e., male and female) occupations were compared with nonintegrated (i.e., male only) occupations. Results: A total of 43,990 AFC stress fractures were identified. The overall incidence rate was 2.76 per 1,000 person-years (p-y) for males and 5.78 per 1,000 p-y for females. Females consistently had higher incidence of AFC stress fractures across all subgroups, particularly among enlisted personnel. Female enlisted service members had the highest risk of AFC stress fractures in aviation (relative risk [RR] = 5.74; 95% confidence interval [CI]: 4.80-6.87) and artillery/gunnery (RR = 5.15; 95% CI: 4.62-5.75) occupations. Females in integrated occupations had significantly higher rates of AFC stress fractures than males in both integrated and nonintegrated occupations (i.e., special forces, infantry, and mechanized/armor). Conclusions: Females in the U.S. military have a higher risk of AFC stress fractures than males. As integration of females into previously sex-restricted occupations continues, focused prevention efforts may be needed to reduce injury burden and maximize medical readiness.

Prosthesis satisfaction and quality of life in US service members with combat-related major lower-limb amputation.

BACKGROUND: Military amputee patient care programs offer extensive services, including advanced prosthetic devices, to restore function and improve quality of life (QOL) among veterans and service members with combat-related limb loss, but research on satisfaction with these devices is limited. OBJECTIVE: To assess prosthesis satisfaction and QOL in US service members and veterans with combat-related major lower-limb amputation. STUDY DESIGN: Cross-sectional study. METHODS: Eighty-six participants with combat-related major lower-limb amputation completed the Orthotics and Prosthetics Users' Survey (OPUS) Satisfaction with Device scale and Quality of Well-Being Scale, Self-Administered, for the Wounded Warrior Recovery Project. RESULTS: Most participants (62%-88%) responded Agree or Strongly Agree to OPUS Satisfaction with Device items on the fit, weight, comfort, ease of donning, appearance, and durability of their prosthesis. By contrast, the majority of participants (55%-79%) responded Disagree or Strongly Disagree to items on clothes being free of wear and tear, skin free of abrasions and irritations, and the affordability of their prosthesis. In linear regression analysis, total OPUS Satisfaction with Device score was positively associated with Quality of Well-Being Scale, Self-Administered score (ß = 0.0058; P = 0.004). CONCLUSIONS: Findings indicate the majority of participants were satisfied with the overall functionality of their prosthesis, but dissatisfied with the effect of their prosthesis on clothing and skin, as well as expenses related to their prosthesis. Additionally, prosthesis satisfaction was positively associated with QOL.