Leading indicators of readiness among the general Army and Special Operations Forces: Predictive and psychometric analysis of the Global Assessment Tool.

Self-assessments are commonly used to track Army readiness in specialized communities, but they are rarely analyzed for reliability and predictive validity. Before introducing new assessments, existing ones should be reevaluated. We examined the Global Assessment Tool (GAT), an annual Army-required self-assessment with multiple psychosocial and health behavior short scales. Psychometric analyses on nine scales included item response theory (IRT) and measurement invariance models across total Army (n = 743,057) and special operations forces (SOF; n = 3,478) cohorts. Predictive analyses examined demographic-adjusted associations between GAT scales and one-year incident medical non-readiness (MNR). Most scales had adequate reliability, although some exhibited highly skewed distributions, which likely increased measurement error. Most scales exhibited metric and scalar measurement equivalence across total Army and SOF groups. Scores from scales measuring positive characteristics were associated with lower odds of MNR (good coping, flexibility, optimism, positive affect, work engagement, friendship, organization trust; adjusted odds ratios ≤ 0.75); scores from scales measuring negative characteristics were associated with increased odds of MNR (poor sleep, depression, negative affect, loneliness; adjusted odds ratios ≥ 1.4). Associations were similar across Army and SOF cohorts. In conclusion, self-report data can potentially contribute to command surveillance, but iterative quality-checks are necessary after deployment.

The combined effects of coping and pain interference on army readiness.

Introduction: Chronic pain and associated interference with daily activities are common in the military and impact Force readiness. Chronic pain affects one-third of service members and is a leading cause of medical non-readiness (MNR) in the military. Research suggests that underlying psychological mechanisms related to trait coping styles and pain interference (PI) affect functional outcomes, but little research exists examining this relationship within an Army population. The purpose of this study was to examine the combined effects of PI and coping on U.S. Army soldier readiness by using annual well-being data from the Global Assessment Tool (GAT) and medical non-readiness (MNR) based on duty restriction records. Methods: The sample comprised 866,379 soldiers who completed the GAT between 2014 and 2017 with no duty restrictions at the time of baseline GAT completion; subjects were observed through 2018 for duty restrictions. Parametric survival regression models with a Weibull distribution predicted demographic-adjusted hazards of MNR by dichotomized PI (no PI/PI) and beneficial/non-beneficial use of GAT coping components (good coping, bad coping, catastrophizing-flexibility, and catastrophizing-hopelessness). Incident MNR was evaluated for all duty restrictions, and stratified by selected body systems (upper extremity, lower extremity, psychiatric). Results: Among soldiers with PI, hazards were higher in those reporting non-beneficial coping styles (bad coping, hopelessness) and lower in those reporting beneficial coping styles (good coping, flexibility). Across all coping styles, PI/coping interactions were particularly strong for catastrophizing-hopelessness and when examining MNR from psychiatric conditions. Discussion: These findings suggest some synergistic associations between pain and coping that may impact pain-related occupational disability. Coping skills may be an effective interventional target for chronic pain reduction/prevention within military programs, such as the Master Resilience Training Course offered to soldiers in the Army. Further research should assess whether early coping style interventions can reduce pain-related outcomes.

Postpartum long-acting reversible contraceptive use among active-duty, female US Army soldiers.

BACKGROUND: Postpartum use of long-acting reversible contraception has been found to be effective at increasing interpregnancy intervals, reducing unintended pregnancies, and optimizing health outcomes for mothers and babies. Among female active-duty military service members, reproductive planning may be particularly important, yet little is known about postpartum long-acting reversible contraceptive use among active-duty soldiers. OBJECTIVE: This study aimed to (1) quantify postpartum uptake of long-acting reversible contraception among active-duty female US Army soldiers and (2) identify demographic and military-specific characteristics associated with use. STUDY DESIGN: This retrospective cohort study used longitudinal data of all digitally recorded health encounters for active-duty US Army soldiers from 2014 to 2017. The servicewomen included in our analysis were aged 18 to 44 years with at least one delivery and a minimum of 4 months of total observed time postdelivery within the study period. We defined postpartum long-acting reversible contraception use as initiation of use within the delivery month or in the 3 calendar months following delivery and identified likely immediate postpartum initiation via the proxy of placement recorded during the same month as delivery. We then evaluated predictors of postpartum long-acting reversible contraception use with multivariable logistic regression. RESULTS: The inclusion criteria were met by 15,843 soldiers. Of those, 3162 (19.96%) initiated the use of long-acting reversible contraception in the month of or within the 3 months following delivery. Fewer than 5% of these women used immediate postpartum long-acting reversible contraception. Among women who initiated postpartum long-acting reversible contraceptive use, 1803 (57.0%) received an intrauterine device, 1328 (42.0%) received an etonogestrel implant, and 31 received both (0.98%). Soldiers of younger age, self-reported White race, and those who were married or previously married were more likely to initiate long-acting reversible contraception in the postpartum period. Race-stratified analyses showed that self-reported White women had the highest use rates overall. When compared with these women, the adjusted odds of postpartum use among self-reported Black and Asian or Pacific Islander women were 18% and 30% lower, respectively (both P<.001). There was also a trend of decreasing postpartum use with increasing age within each race group. Differences observed between age groups and race identities could partially be attributed to differential use of permanent contraception (sterilization), which was found to be significantly more prevalent among both women aged 30 years or older and among women who identified as Black. CONCLUSION: Among active-duty US Army servicewomen, 1 in 5 used postpartum long-acting reversible contraception, and fewer than 5% of these women used an immediate postpartum method. Within this population with universal healthcare coverage, we observed relatively low rates of use and significant differences in the uptake of effective postpartum long-acting contraceptive methods across self-reported race categories.

Physical Fitness in Relationship to Depression and Post-Traumatic Stress Disorder During Pregnancy Among U.S. Army Soldiers.

Background: Depression and post-traumatic stress disorder (PTSD) are prevalent in pregnancy, especially among military members. These conditions can lead to adverse birth outcomes, yet, there's a paucity of evidence for prevention strategies. Optimizing physical fitness is one understudied potential intervention. We explored associations between prepregnancy physical fitness and antenatal depression and PTSD in soldiers. Materials and Methods: This was a retrospective cohort study of active-duty U.S. Army soldiers with live births between 2011 and 2014, identified with diagnosis codes from inpatient and outpatient care. The exposure was each individual's mean Army physical fitness score from 10 to 24 months before childbirth. The primary outcome was a composite of active depression or PTSD during pregnancy, defined using the presence of a code within 10 months before childbirth. Demographic variables were compared across four quartiles of fitness scores. Multivariable logistic regression models were conducted adjusting for potential confounders selected a priori. A stratified analysis was conducted for depression and PTSD separately. Results: Among 4,583 eligible live births, 352 (7.7%) had active depression or PTSD during pregnancy. Soldiers with the highest fitness scores (Quartile 4) were less likely to have active depression or PTSD in pregnancy (Quartile 4 vs. Quartile 1 adjusted odds ratio 0.55, 95% confidence interval 0.39-0.79). Findings were similar in stratified analyses. Conclusion: In this cohort, the odds of active depression or PTSD during pregnancy were significantly reduced among soldiers with higher prepregnancy fitness scores. Optimizing physical fitness may be a useful tool to reduce mental health burden on pregnancy.

Financial Impact of Embedded Injury-Prevention Experts in US Army Initial Entry Training.

CONTEXT: The US Army embedded injury-prevention experts (IPEs), specifically athletic trainers and strength and conditioning coaches, into initial entry training (IET) to limit musculoskeletal (MSK) conditions and their negative consequences. However, little is known about the financial impact of IPEs. OBJECTIVE: To assess whether IPEs were associated with fewer sunk training costs due to MSK-related early discharges from service. DESIGN: Retrospective cohort study. SETTING: Database of US Army soldiers' administrative, medical, and readiness records. PATIENTS OR OTHER PARTICIPANTS: A total of 198 166 soldiers (age = 20.7 ± 3.2 years, body mass index = 24.4 ± 3.5 kg/m2) who began IET during 2014 to 2017. MAIN OUTCOME MEASURE(S): Early discharge from service was defined as occurring within 6 months of beginning IET. All IET sites employed IPEs from 2011 to 2017, except for 2 sites during April to November 2015. Soldiers who began IET at these 2 sites during these times were categorized as not having IPE exposure. All others were categorized as having IPE exposure. The unadjusted association between IPE access and MSK-related early discharge from service was assessed using logistic regression. Financial impact was assessed by quantifying differences in yearly sunk costs between groups with and those without IPE exposure and subtracting IPE hiring costs. RESULTS: Among 14 094 soldiers without IPE exposure, 2.77% were discharged early for MSK-related reasons. Among 184 072 soldiers with IPE exposure, 1.01% were discharged. Exposure to IPEs was associated with reduced odds of MSK-related early discharge (odds ratio = 0.36, 95% CI = 0.32, 0.40, P < .001) and a decrease in yearly sunk training costs of $11.19 to $20.00 million. CONCLUSIONS: Employing IPEs was associated with reduced sunk costs because of fewer soldiers being discharged from service early for MSK-related reasons. Evidence-based recommendations should be developed for guiding policy on the roles and responsibilities of IPEs in the military to reduce negative outcomes from MSK conditions and generate a positive return on investment.

Incidence of Ankylosing Spondylitis Among Male and Female United States Army Personnel.

OBJECTIVE: Incidence rates of ankylosing spondylitis (AS) among males versus females are poorly understood. Results of prior research have been mixed, including findings of a 3:1 incidence ratio for males versus females, but with increasing AS rates among females. The objective was to estimate the incidence of AS among members of the US military. METHODS: We estimated the incidence of AS in a retrospective cohort study of diverse, working-age US military service members during March 2014 to June 2017 (n = 728,556) who underwent clinical practice guideline-directed screening for chronic back pain. Incident AS cases were identified using diagnostic codes from electronic medical and administrative records. RESULTS: In contrast to some prior studies, AS incidence was similar among males and females (incidence rate ratio 1.16, P = 0.23; adjusted odds ratio [OR] 0.79 [95% confidence interval (95% CI) 0.61-1.02]; P = 0.072). AS rates increased approximately monotonically with age. Consistent with prior research, the AS incidence rate was greater in the White population than in the Black population (adjusted OR 1.39 [95% CI 1.01-1.66]; P = 0.04). CONCLUSION: In this study population, the incidence of AS was similar for the sexes. Previous observations of male predominance have typically been derived from clinic populations that are less representative of the US race/ethnicity distribution and based on disease ascertainment tools that may have identified subjects later in their disease course. Our study population also differed in being subject to organized screenings for musculoskeletal symptoms. Our findings suggest that sex may not predict AS incidence in the US population.

Rates of Lapidus Procedures in the US Military Before and After the Advent of and Advocacy for Tri-Plane Lapidus Corrective Surgery.

Tri-plane corrective Lapidus surgery has been described as advantageous with respect to its anatomic basis and outcomes. Because the procedure has been broadly publicized, changes in overall Lapidus procedure rates due to increased numbers of patients opting for the tri-plane approach could have occurred. Data supporting this possibility appears lacking. We employed official personnel and health records of the total active-duty US military to conduct a retrospective cohort study of Lapidus surgery rates before and after the advent of the tri-plane corrective Lapidus procedure. Least-squares and locally-weighted scatterplot smoother regression functions were used to confirm time trends. Sociodemographic and occupational traits of Lapidus patients were compared using 2-sided t tests and chi square tests. Lapidus surgery rates among hallux valgus patients decreased during 2014 to 2016 and increased during 2017 to 2021. While multiple factors might explain these trends, they coincide with the advent of and advocacy for tri-plane Lapidus surgery. The results support the possibility that its rise influenced overall Lapidus rates in this population. As these findings represent limited evidence of such an influence, further research is required to confirm a causal link. If such a link is found, and if the ongoing research suggests that superior outcomes are associated with tri-plane Lapidus surgery, substantial implications could exist for this population. Benefits might include enhanced medical readiness due to the importance of lower extremity function during military duties. Additional research is needed to confirm the impact of the procedure and to determine whether Lapidus surgery rate patterns in civilian populations mirror these findings.

Service discharges among US Army personnel with selected musculoskeletal and skin conditions: a retrospective cohort study.

OBJECTIVES: To determine the probability of discharge from military service among soldiers following an incident diagnosis of ankylosing spondylitis (AS), rheumatoid arthritis (RA), psoriasis or systemic lupus erythematous. METHODS: All soldiers on active duty in the US Army between January 2014 and June 2017 were included in a retrospective cohort analysis. Termination from service was ascertained using personnel records. Diagnostic codes were used to identify incident cases of the four musculoskeletal and skin diseases and, for comparison, diabetes mellitus (DM). Time to discharge was modelled using sex stratified multivariate survival analysis. RESULTS: The analysis included 657 417 individuals with a total of 1.2 million person-years of observation. An elevated risk of discharge was observed in association with each of the five chronic conditions studied. The increase in adjusted risk of discharge was highest among soldiers with AS (men, HR=2.5, 95% CI 2.1 to 3.0; women, HR=2.1, 95% CI 1.4 to 3.2) and with DM (men, HR=2.4, 95% CI 2.2 to 2.7; women, HR=2.2, 95% CI 1.8 to 2.5), followed by those with RA (men, HR=1.8, 95% CI 1.5 to 2.2; women, HR=1.8, 95% CI 1.4 to 2.4). CONCLUSIONS: Military discharges are consequential for the service and the service member. The doubling in risk of discharge for those with AS or RA was comparable to that for personnel with DM. Conditions that affect the spine and peripheral joints may often be incompatible with military readiness. Nevertheless, a substantial fraction of service members with these diagnoses continued in service.

Aiding the prescriber: developing a machine learning approach to personalized risk modeling for chronic opioid therapy amongst US Army soldiers.

The opioid epidemic is a major policy concern. The widespread availability of opioids, which is fueled by physician prescribing patterns, medication diversion, and the interaction with potential illicit opioid use, has been implicated as proximal cause for subsequent opioid dependence and mortality. Risk indicators related to chronic opioid therapy (COT) at the point of care may influence physicians' prescribing decisions, potentially reducing rates of dependency and abuse. In this paper, we investigate the performance of machine learning algorithms for predicting the risk of COT. Using data on over 12 million observations of active duty US Army soldiers, we apply machine learning models to predict the risk of COT in the initial months of prescription. We use the area under the curve (AUC) as an overall measure of model performance, and we focus on the positive predictive value (PPV), which reflects the models' ability to accurately target military members for intervention. Of the many models tested, AUC ranges between 0.83 and 0.87. When we focus on the top 1% of members at highest risk, we observe a PPV value of 8.4% and 20.3% for months 1 and 3, respectively. We further investigate the performance of sparse models that can be implemented in sparse data environments. We find that when the goal is to identify patients at the highest risk of chronic use, these sparse linear models achieve a performance similar to models trained on hundreds of variables. Our predictive models exhibit high accuracy and can alert prescribers to the risk of COT for the highest risk patients. Optimized sparse models identify a parsimonious set of factors to predict COT: initial supply of opioids, the supply of opioids in the month being studied, and the number of prescriptions for psychotropic medications. Future research should investigate the possible effects of these tools on prescriber behavior (e.g., the benefit of clinician nudging at the point of care in outpatient settings).

Post-Traumatic Stress Disorder Among U.S. Army Drone Operators.

INTRODUCTION: Exposure to traumatic events could increase post-traumatic stress disorder (PTSD) risk among enlisted U.S. Army drone operators. Published research on PTSD risk in this population is unavailable.METHODS: We used a combined medical and administrative longitudinal dataset to examine adjusted associations between drone operator service among U.S. Army enlisted members and three PTSD indicators: whether screened via the PTSD Checklist - Civilian (PCL-C); PCL-C scores; and incident PTSD diagnoses. We compiled summary statistics for and conducted tests of differences in independent variable distributions when comparing drone operators and others. Two multivariable survival regression models and an ordinary least squares model were used to estimate adjusted associations.RESULTS: There were 1.68 million person-years of observed time in the study population (N = 678,548; drone operator N = 2856). Compared to other servicemembers, the adjusted likelihood of undergoing PTSD screening was 35% lower [95% confidence interval (CI) for the adjusted hazard ratio (aHR): 0.56-0.76]. Among subjects who took the PCL-C, scores did not differ significantly on the basis of drone operator service (adjusted change: -1.26 points; CI: -3.41-0.89). The adjusted hazard of receiving a PTSD diagnosis was 34% lower among drone operators (CI: 0.54-0.80).DISCUSSION: These findings provide reassurance that enlisted U.S. Army drone operators are not at increased risk of PTSD. Further research is needed in order to identify the mechanisms of the decreased PTSD risk observed, and whether other or longer-term mental health risks are present among those in this occupation.Nelson DA, Wilson M, Kurina LM. Post-traumatic stress disorder among U.S. Army drone operators. Aerosp Med Hum Perform. 2022; 93(7):562-570.

An investigation of sickle cell trait, body mass index, and fitness in relation to venous thromboembolism among African American adults.

BACKGROUND: The relationships of sickle cell trait (SCT), body mass index (BMI), and physical fitness to venous thromboembolism (VTE) in young adults have received little attention. OBJECTIVES: To test for associations among SCT, BMI, fitness, and VTE. PATIENTS/METHODS: We conducted a retrospective cohort study of 48,316 SCT-tested, African American individuals in the US Army during 2011-14. We used Cox proportional hazards models to compute adjusted hazards of deep vein thrombosis (DVT) and pulmonary embolism (PE) associated with selected factors. RESULTS: Incidence rates of DVT and PE were 1.09 and 0.91 cases per 1000 person-years, respectively. Adjusted hazard ratios (aHRs) for DVT for men and women with SCT were 0.9 (95% confidence interval [CI]: 0.4-2.0; P = .711) and 1.51 (CI: 0.7-3.2; P = .274), respectively. aHRs for PE for SCT+ men and women were 1.1 (CI: 0.5-2.4; P = .773) and 1.2 (CI: 0.5-3.1; P = .650), respectively. Low physical fitness was associated with DVT and PE in women (DVT aHR =3.1; CI: 1.4-6.5; P = .004; PE aHR =4.6; CI: 2.1-9.9; P < .001) and DVT in men (aHR =2.2; CI: 1.0-4.6; P = .048). Recent weight gain of 1 or more BMI points was associated with DVT in men (aHR =1.8; CI: 1.1-2.8; P = .017). CONCLUSIONS: We found no evidence of increased VTE risk associated with SCT in this population. However, lower fitness levels and BMI increases were so associated.

Summit on Exercise Collapse Associated with Sickle Cell Trait: Finding the "Way Ahead".

ABSTRACT: Although largely benign, sickle cell trait (SCT) has been associated with exertion-related events, to include sudden death. In 2011, a summit on SCT introduced the term exercise collapse associated with SCT (ECAST). A series of ECAST deaths in military personnel in 2019 prompted reevaluation of current efforts and led to a second summit in October 2019 hosted by the Consortium for Health and Military Performance of the Uniformed Services University in Bethesda, MD. The goals were to (1) review current service policies on SCT screening, (2) develop draft procedural instructions for executing current policy on SCT within the Department of Defense, (3) develop draft clinical practice guidelines for management of ECAST, (4) establish a framework for education on SCT and ECAST, and (5) prepare a research agenda to address identified gaps.

Incidence of Pelvic Floor Disorders in US Army Female Soldiers.

OBJECTIVE: To determine the incidence of pelvic floor disorders (PFD) among active-duty US Army female soldiers. MATERIALS AND METHODS: We studied 102,015 women for incident PFD using the Stanford Military Data Repository, which comprises medical, demographic and service-related information on all soldiers on active duty in the US Army during 2011-2014. Cox proportional hazards estimated adjusted associations with PFD diagnoses. In the adjusted models, military-specific characteristics and fitness were evaluated alongside known PFD predictors. RESULTS: Among 102,015 subjects at risk there was a cumulative incidence of 6.4% over a mean of 27 months (median 29, range 1-42). In adjusted models, obese soldiers were more likely to have a PFD compared to those of normal weight (hazard ratio [HR] 1.23, confidence interval [CI] 1.14-1.34, P <0.001) and those with recent weight gain were more likely to have a PFD compared to those without (HR 1.32, CI 1.24-1.40, P <0.05). Women with the lowest physical fitness scores were more likely to have a PFD (HR 1.14, CI 1.04-1.25) compared to those with the highest scores. CONCLUSION: Over a median follow-up time of 29 months, 1 in 15 women in this active-duty cohort was diagnosed with a PFD. Optimizing risk factors including body mass index and physical fitness may benefit the pelvic health of female soldiers, independent of age, children, and years of service.

Military Occupational Disability Risk Surveillance: A Retrospective Cohort Study of Modifiable Risk Factors.

INTRODUCTION: Occupational disability among military service members is an important target for preventive screening. The specific aim of this study was to quantify disability risk levels among soldiers with selected risk factors (body mass index extremes, poor or absent physical fitness scores, and tobacco and opioid use) and combinations thereof, suggesting priorities for preventive actions. MATERIALS AND METHODS: This was a retrospective cohort study of 607,006 active-duty soldiers who served in the U.S. Army during 2011-2014. Official medical and administrative data were combined to produce a person-month-based panel dataset with identifiers removed. The subjects were observed longitudinally for incident disability (termed medical nonreadiness) during 1,305,618 person-years at risk. We employed Weibull parametric survival regression models to determine the adjusted medical nonreadiness hazard for selected variables. We then computed individual adjusted risk scores and the population proportions affected by risk factors and combinations thereof in postregression analyses. The project was approved by the Stanford University's Institutional Review Board and underwent secondary review by the Human Research Protections Office of the Defense Health Agency. RESULTS: During the observed time, 81,571 (13.4%) of subjects were found medically not ready. High or low body mass index, low or missing physical fitness test scores, tobacco use, and the highest levels of opioid use were each associated with increased adjusted hazards of medical nonreadiness. The hazards increased substantially when multiple risk factors were present, albeit while affecting reduced population proportions. CONCLUSIONS: We identified marked disability hazard increases, especially in association with opioid use and high body mass index. These factors, in addition to tobacco use and low physical fitness, are potential early prevention targets for clinicians who screen military service members.

Stressful Life Changes and Their Relationship to Nutrition-Related Health Outcomes Among US Army Soldiers.

Stressful life changes may tax people's adaptive capacity. We sought to determine if and when experiences of stressful life changes were associated with increased odds of adverse nutrition-related health outcomes among US Army soldiers relative to those who did not experience the same stressful life change. An additional aim was to determine which stressful life changes had the greatest association with these outcomes and if there were gender differences in the magnitude of the associations. Stressful life changes studied included: changes in marital status, combat deployment or return from deployment, relocation, adding a child, change in rank, change in occupation, and development of a physical limitation to duty. Using longitudinal data from the Stanford Military Data Repository, which represents all active-duty soldiers aged 17-62 between 2011 and 2014 (n = 827,126), we employed an event history analysis to examine associations between stressful life changes and a subsequent diagnosis of hyperlipidemia, substantial weight gain, and weight-related separation from the Army. Marriage was associated with an increase in the odds of substantial weight gain 3 months later for both men and women. Developing a physical duty limitation was associated with an increase in the odds of a hyperlipidemia diagnosis 2 months later for both men and women, as was substantial weight gain 2 months later. Stressful life changes were also associated with increased odds of nutrition-related health outcomes, although we found gender differences in the magnitude of the associations. Findings could be used to mitigate the effects of stress on health by health professionals.

The Value of Shorter Initial Opioid Prescriptions: A Simulation Evaluation.

BACKGROUND: During the period from 1999 to 2016, more than 350,000 Americans died from overdoses related to the use of prescription opioids. To the extent that supply is directly related to overprescribing, policy interventions aimed at changing prescriber behavior, such as the recent Centers for Disease Control and Prevention guideline, are clearly warranted. Although these could plausibly reduce the prevalence of opioid overuse and dependency, little is known about their economic and health-related impacts. OBJECTIVE: The aim of this study was to quantify the efficacy of a policy intervention aimed at reducing the length of initial opioid prescriptions. STUDY DESIGN AND METHODS: A Markov decision process model was fitted on a retrospective cohort of 827,265 patients, and patient cost and health trajectories were simulated over a 24-month period. The model's parameters were based on patients who received short (≤ 3 days) or long (> 7 days) initial opioid prescriptions, matched using propensity score methods. STUDY POPULATION: All active-duty US Army soldiers from 2011 to 2014; the data contained detailed medical and administrative information on over 11 million soldier-months corresponding to 827,265 individual soldiers. MAIN OUTCOME MEASURE: Overall costs of a policy change, quality-adjusted life-years (QALYs) gained, and $/QALY gained. RESULTS: Over a 2-year horizon, a reassignment of 10,000 patients to short initial duration would generate a cost saving in the vicinity of $3.1 million (excluding program costs), and would also lead to an estimated 4451 additional opioid-free months, i.e. months without any opioid prescriptions. CONCLUSION: The analysis found that efforts to change prescriber behavior can be cost effective, and further studies into the implementation of such policies are warranted.

Sickle cell trait and renal disease among African American U.S. Army soldiers.

Sickle cell trait and certain renal disorders are disproportionately prevalent among African American individuals, so a clear understanding of their association is important. We conducted a longitudinal study using the Stanford Military Data Repository to examine sickle cell trait in relation to the incidence of acute kidney injury (AKI) and chronic kidney disease (CKD). Our study population consisted of African American U.S. Army soldiers on active duty between January 2011 and December 2014. The cumulative incidence was 0·51% for AKI (236 cases out of 45 901 soldiers) and 0·56% for CKD (255 cases out of 45 882 soldiers). Discrete time logistic regression models adjusting for demographic-, military- and healthcare-related covariates showed that sickle cell trait was associated with significantly higher adjusted odds of both AKI [odds ratio (OR): 1·74; 95% confidence interval (CI): 1·17-2·59] and CKD (OR: 2·00; 95% CI: 1·39-2·88). Elevated odds of AKI and CKD were also observed in association with prior CKD and AKI, respectively, and with obesity and prior hypertension. Individuals with sickle cell trait and their providers should be aware of the possibility of increased risk of AKI and CKD to allow for timely intervention and possible prevention.

Association of Nonsteroidal Anti-inflammatory Drug Prescriptions With Kidney Disease Among Active Young and Middle-aged Adults.

Importance: Concern about the renal effects of nonsteroidand al anti-inflammatory drugs (NSAIDs) among young, healthy adults has been limited, but more attention may be warranted given the prevalent use of these agents. Objective: To test for associations between dispensed NSAIDs and incident acute kidney injury and chronic kidney disease while controlling for other risk factors. Design, Setting, and Participants: This retrospective, longitudinal cohort study used deidentified medical and administrative data on 764 228 active-duty US Army soldiers serving between January 1, 2011, and December 31, 2014. Analysis was conducted from August 1 to November 30, 2018. All individuals new to Army service were included in the analysis. Persons already serving in January 2011 were required to have at least 7 months of observable time to eliminate those with kidney disease histories. Exposures: Mean total defined daily doses of prescribed NSAIDs dispensed per month in the prior 6 months. Main Outcomes and Measures: Incident outcomes were defined by diagnoses documented in health records and a military-specific digital system. Results: Among the 764 228 participants (655 392 [85.8%] men; mean [SD] age, 28.6 [7.9] years; median age, 27.0 years [interquartile range, 22.0-33.0 years]), 502 527 (65.8%) were not dispensed prescription NSAIDs in the prior 6 months, 137 108 (17.9%) were dispensed 1 to 7 mean total defined daily doses per month, and 124 594 (16.3%) received more than 7 defined daily doses per month. There were 2356 acute kidney injury outcomes (0.3% of participants) and 1634 chronic kidney disease outcomes (0.2%) observed. Compared with participants who received no medication, the highest exposure level was associated with significantly higher adjusted hazard ratios (aHRs) for acute kidney injury (aHR, 1.2; 95% CI, 1.1-1.4) and chronic kidney disease (aHR, 1.2; 95% CI, 1.0-1.3), with annual outcome excesses per 100 000 exposed individuals totaling 17.6 cases for acute kidney injury and 30.0 cases for chronic kidney disease. Conclusions and Relevance: Modest but statistically significant associations were noted between the highest observed doses of NSAID exposure and incident kidney problems among active young and middle-aged adults.

Trajectories of body mass index among active-duty U.S. Army soldiers, 2011-2014.

Establishing the shape and determinants of trajectories of body mass index (BMI) among Soldiers is critical given the importance of weight management to military service requirements. To establish the shape and determinants of BMI trajectories among Soldiers, we aimed to (1) model the overall BMI trajectory of Soldiers, (2) find the most common trajectory groups among Soldiers, (3) investigate the relationship between BMI trajectories and sociodemographic and military-specific characteristics, and (4) determine if there were Soldiers with large fluctuations in BMI. The study population included all US Army Soldiers on active-duty between 2011 and 2014 who were age 17-62 (n = 827,126). With longitudinal data from the Stanford Military Data Repository, we used group-based trajectory modeling to identify the BMI trajectories of Soldiers and multinomial logistic regression to estimate associations between Soldier characteristics and trajectory membership. Four distinct BMI trajectory groups were found: increasing, decreasing, constant, and inconstant. The constant, increasing, and decreasing trajectories were similar in shape and percentage between men and women. The constant trajectory had the fewest Soldiers who exceeded weight standards or had duty limitations. The increasing trajectory was associated with marriage and fewer service years. The decreasing trajectory was associated with more service years and higher educational attainment. The inconstant trajectory differed in shape between men and women. Over 6% of men and 12% of women had fluctuations in BMI indicative of weight cycling. Understanding the characteristics associated with BMI trends may assist the Army in targeting resources aimed to improve Soldier health and combat readiness.