The relative impact of injury and deployment on mental and physical quality of life among military service members.

US service members injured in the recent conflicts in Iraq and Afghanistan were more likely to survive than those in previous conflicts because of advances in medicine and protective gear. However, there is limited research examining the long-term impact of injuries while deployed on physical and mental quality of life (QOL) among service members. We used data from two time-points with an average follow-up period of 4.27 years (SD = 2.13; n = 118,054) to prospectively examine the association between deployment and injury status with QOL. Data were derived from the Millennium Cohort Study surveys (2001 to 2016) and linked with the Department of Defense Trauma Registry (DoD-TR) among a cohort of US service members from all branches and components. The primary predictor (a combination of deployment and injury status) was comprised of the following four categories: 1) not deployed, 2) deployed and not injured, 3) deployed and non-battle injured, and 4) deployed and battle injured. Demographic, military, psychological and behavioral health, and life stress factors were adjusted for in multivariable models. Outcomes of interest were physical and mental QOL from the Short-Form Health Survey for Veterans (VR-36) measured at ~4 year follow-up. Between group comparisons indicated that those deployed and battle-injured had the greatest decline in both mental (-3.82) and physical (-10.13) QOL scores over time (p < .05). While deployment and injury status were associated with poorer mental and physical QOL in adjusted models; only the association between deployment and injury status with physical QOL was clinically meaningful (more than 2.5). In adjusted models, Time 1 mental and physical QOL explained most of the variance (23-25%) in Time 2 mental and physical health QOL as compared to other covariates (e.g., injury and deployment, and other sociodemographic factors increased variance by ~5%). Time 1 QOL was the most significant predictor of later QOL, but those injured while deployed experienced significant and meaningful decrements to long-term physical QOL. This suggests that prevention and rehabilitation interventions should focus on improving physical health among injured service members to avoid long-term adverse effects.

Heart Rate Response, Duration, Grip Strength, and Anthropometric Characteristics in Recreational Indoor Rock Climbers.

ABSTRACT: Smetanka, RG, Armenta, RF, Nessler, JA, and Newcomer, SC. Heart rate response, duration, grip strength, and anthropometric characteristics in recreational indoor rock climbers. J Strength Cond Res 36(3): 832-837, 2022-Despite the growing popularity of recreational indoor rock climbing, there is a lack of research on cardiovascular responses to rock climbing. In addition, although the importance of body composition and grip strength has been established in elite climbers, their effect on recreational climbing is unknown. Therefore, the purpose of this study was to characterize the physiological and anthropometric characteristics of indoor climbers engaging in climbing at a recreational or noncompetitive setting. We hypothesized that heart rates and climbing durations would meet the standards set by the American College of Sports Medicine (ACSM) and Center for Disease Control and Prevention (CDC) for eliciting health benefits and that grip strength would decrease over the course of a typical climbing session. One hundred twenty-one male and female adult recreational climbers participated in this study. Following informed consent, subjects were instrumented with a heart rate monitor (Polar V800) which recorded heart rate and duration. Preclimb and postclimb grip strength were evaluated using a hand grip dynamometer and used to calculate fatigue. Subjects were 30.9 ± 8.3 years old and had participated in climbing for 5.6 ± 6.5 years. The average heart rate during climbing sessions was 122.3 ± 14.5 b·min-1, and session duration was 90.6 ± 31.3 minutes. Mean grip strength was 49.9 ± 11.2 kg, whereas the strength to mass ratio was 0.71 ± 0.14, and fatigue was 13.1 ± 11.6%. Results from the current study suggest that recreational indoor climbing elicits exercise heart rates and durations that are consistent with the CDC and ACSM's recommendations for cardiovascular health. Grip strength data suggested that forearm muscle fatigue may limit climbing durations.

Sexual Health Problems among Service Men: The Influence of Posttraumatic Stress Disorder.

Military operational stressors, such as combat exposure, may increase the risk of sexual health problems. This study examined factors associated with sexual health problems, and tested the mediating effect of probable posttraumatic stress disorder (PTSD) on the association between stressors (i.e., combat deployment and sexual assault) and sexual health problems among U.S. service men. Using multivariable logistic regression (n = 16,603) and Cox proportional hazards models (n = 15,330), we estimated the risk of self-reported sexual health difficulties and sexual dysfunction medical encounters, respectively. Mediation analyses examined the effect of probable PTSD as an intermediate factor between high combat deployment and sexual assault on sexual health problems. Approximately 9% endorsed sexual health difficulties and 8% had a sexual dysfunction. Risk factors for these sexual health problems included older age, lower education level, enlisted rank, disabling injury, certain medical conditions, and higher body mass index. Probable PTSD significantly mediated the associations between high combat with sexual health problems and sexual assault with sexual dysfunction. Additionally, high combat was directly associated with sexual health difficulties. These findings indicate a relationship between these stressors and sexual health problems which suggests that treatment options should be expanded, especially to include psychogenic sexual dysfunctions.

Contribution of Concurrent Comorbidities to Sepsis-Related Mortality in Preterm Infants ≤32 Weeks of Gestation at an Academic Neonatal Intensive Care Network.

OBJECTIVE: This study sought to identify concurrent major comorbidities in preterm infants ≤32 weeks of gestation that may have contributed to sepsis-related mortality following a diagnosis of bacteremia or blood culture-negative sepsis within the neonatal period (≤28 days of life). STUDY DESIGN: This is a retrospective chart review of infants ≤32 weeks of gestation who were admitted to a single academic network of multiple neonatal intensive care units between January 1, 2012, and December 31, 2015, to determine the primary cause(s) and timing of death in those diagnosed with bacteremia or blood culture-negative sepsis. Direct comparisons between early-onset sepsis (EOS; ≤72 hours) and late-onset sepsis (LOS; >72 hours) were made. RESULTS: In our study cohort, of 939 total patients with ≤32 weeks of gestation, 182 infants were diagnosed with 198 episodes of sepsis and 7.7% (14/182) died. Mortality rates did not significantly differ between neonates with bacteremia or blood culture-negative sepsis (7/14 each group), and those diagnosed with EOS compared with LOS (6/14 vs. 8/14). Nearly 80% (11/14) of infants were transitioned to comfort care prior to their death secondary to a coinciding diagnosis of severe grade-3 or -4 intraventricular hemorrhage, periventricular leukomalacia, necrotizing enterocolitis, and/or intestinal perforation. CONCLUSION: Preexisting comorbidities commonly associated with extreme preterm birth contributed to sepsis-related mortality in our patient cohort. KEY POINTS: · Concurrent comorbidities contribute to, and may artificially inflate, sepsis-related mortality.. · Absence of a consensus definition for neonatal sepsis complicates the investigation of infection.. · Accurate assessment of the incidence of sepsis in very low birth weight infants is vital for future investigations.

Sexual health difficulties among service women: the influence of posttraumatic stress disorder.

Background Sexual health among service women remains understudied, yet is related to health and quality of life. This study examined if the associations between recent combat and sexual assault with sexual health difficulties were mediated by mental disorders and identified factors associated with sexual health difficulties among service women. Methods Data from two time points (2013 and 2016) of the Millennium Cohort Study, a large military cohort, were used. The outcome was self-reported sexual health difficulties. Mediation analyses examined probable posttraumatic stress disorder (PTSD) and major depressive disorder (MDD) as intermediate variables between recent combat and sexual assault with the sexual health difficulties. Multivariable logistic regression modeling was used to examine the association of demographic, military, historical mental health, life stressors, and physical health factors with sexual health difficulties. Results Of the 6,524 service women, 13.5% endorsed experiencing sexual health difficulties. Recent combat and sexual assault were significantly associated with sexual health difficulties. Probable PTSD mediated the associations of recent combat and sexual assault with sexual health difficulties; probable MDD did not mediate these relationships. Other significant factors associated with sexual health difficulties included enlisted rank, historical mental disorders, childhood trauma, and disabling injury. Limitations Use of self-reported data, outcome not assessed using a standardized measure and future studies may benefit from examining other mediators. Conclusion Our findings that combat and sexual assault may have negative effects on service women's sexual health suggest that treatment options and insurance coverage for sexual health problems should be expanded.

Upper limb manual dexterity, strength and blood flow after walking with backpack load.

This study aimed to characterize the effects of walking with backpack load on upper limb function. Fifteen males participated in 3 conditions: no load, 40% body weight loaded backpack (BP) and loaded backpack with simulated rifle (BRC). Pinch strength, grip strength, sensory threshold, blood flow volume, and a manual dexterity test were assessed before and after a 45-min walking trial. Pinch strength in the BP condition was significantly different than the control (p < 0.05). Grooved pegboard times were faster after a seated recovery (p = 0.026) than immediately after walking with load. Blood flow was significantly decreased to <53% of baseline (p ≤ 0.001) in BP and BRC immediately after donning the backpack. No significant changes in grip strength or sensory threshold were measured among conditions or time points. In conclusion, pinch strength, manual dexterity and blood flow were affected by backpack carriage, but other upper limb measures remained unaffected.

Fluid Loss in Recreational Surfers.

Surfing offers unique challenges to thermoregulation and hydration. The purpose of this study was to quantify fluid loss in recreational surfers, and to analyze the effects of water temperature, air temperature, exercise intensity, duration, and garment thickness on the total amount of fluid lost during a surf session. A total of 254 male and 52 female recreational surfers were recruited from San Diego, Costa Rica, and Australia to participate in the study. Participants' hydration status was assessed by comparing nude body mass pre- and post-surf session. Heart rate (HR), used as an index of exercise intensity, was measured throughout the session. Environmental conditions and surf characteristics were recorded. The difference between average pre-mass (73.11 ± 11.88 kg) and average post-mass (72.51 ± 11.78) was statistically significant (0.60 ± 0.55, p < 0.001). Surfers experienced a 0.82 ± 0.73% reduction in body mass. In multivariable linear regression, session duration and body mass index (BMI) were significantly associated with fluid loss. For every 10-minute increase in session duration, there was a 0.06 kg (SE = 0.001; p < 0.001) increase in fluid loss, and for every two unit increase in BMI, fluid loss increased by 0.05 kg (SE = 0.03; p = 0.02). Results suggest that prolonged surfing at high environmental temperatures in participants with high BMI's resulted in significant body water deficits. Since there is no opportunity to rehydrate during a surf session, surfers must properly pre-hydrate before surfing in order to avoid the detrimental effects of dehydration.

"There Is a Lot of Practice in Not Thinking about That": Structural, Interpersonal, and Individual-Level Barriers to HIV/STI Prevention among Reservation Based American Indians.

American Indians (AI) face significant disparities in HIV/STI morbidity and mortality, and historical, structural, interpersonal, and individual level barriers stymie prevention efforts. The objective of this paper is to examine barriers to HIV/STI prevention among reservation-based AI. We conducted face-to-face qualitative interviews with 17 reservation-based AI community leaders and community members in Southern California on HIV/STI knowledge and attitudes and barriers to prevention. The disruption of traditional coping mechanisms and healing processes were compromised by historical trauma, and this allowed stigmas to exist where they did not exist before. This impacted access to healthcare services and trust in medicine, and is linked to individuals adopting negative coping behaviors that confer risk for HIV/STI transmission (e.g., substance use and sexual behaviors). Most of the participants reported that HIV/STIs were not discussed in their reservation-based communities, and many participants had a misperception of transmission risk. Stigma was also linked to a lack of knowledge and awareness of HIV/STI's. Limited available services, remoteness of communities, perceived lack of privacy, and low cultural competency among providers further hindered the access and use of HIV/STI prevention services. These findings highlight the need to address the historical, structural, and interpersonal factors impacting individual-level behaviors that can increase HIV/STI transmission among reservation-based AIs. Prevention work should build on community strengths to increase HIV/STI knowledge, reduce stigma, and increase access to preventative care while using culturally grounded methodologies.

Hypertension in military veterans is associated with combat exposure and combat injury.

BACKGROUND: Although the long-term effects of combat injury are not well understood, there is emerging concern that exposure to combat environments and subsequent injury may increase the risk of hypertension through changes in inflammatory responses, psychological stress and mental health, and health behaviors. METHODS: Data from the Millennium Cohort Study and the Department of Defense Trauma Registry were used to identify combat-exposed and combat-injured participants. Incident hypertension diagnoses were ascertained from the Millennium Cohort survey. The associations between combat exposure/injury and hypertension risk was estimated using multivariable complementary log-log survival models. RESULTS: The final analysis sample consisted of 38 734 participants. Of these, 50.8% deployed but were not exposed to combat, 48.6% deployed and were exposed to combat, and 0.6% had combat injury. Overall prevalence of hypertension was 7.6%. Compared with participants who deployed but did not experience combat (mild exposure), elevated odds of hypertension were observed among those who experienced combat but not wounded (moderate exposure; AOR, 1.28; 95% CI, 1.19-1.38) and those wounded in combat (high exposure; AOR, 1.46; 95% CI, 1.07-2.00). Sleep duration of less than 4 h (AOR, 1.21; 95% CI, 1.03-1.43), sleep duration of 4-6 h (AOR, 1.16; 95% CI, 1.05-1.29), posttraumatic stress disorder (AOR, 1.54; 95% CI, 1.26-1.87), and overweight (AOR, 1.77; 95% CI, 1.61-1.95) and obese (AOR, 2.77; 95% CI, 2.45-3.12) status were also associated with higher odds of hypertension. CONCLUSION: Results support the hypotheses that combat exposure increases hypertension risk and that combat injury exacerbates this risk.

Longitudinal trajectories of comorbid PTSD and depression symptoms among U.S. service members and veterans.

BACKGROUND: Posttraumatic stress disorder (PTSD) often co-occurs with other psychiatric disorders, particularly major depressive disorder (MDD). The current study examined longitudinal trajectories of PTSD and MDD symptoms among service members and veterans with comorbid PTSD/MDD. METHODS: Eligible participants (n = 1704) for the Millennium Cohort Study included those who screened positive at baseline for both PTSD (PTSD Checklist-Civilian Version) and MDD (Patient Health Questionnaire). Between 2001 and 2016, participants completed a baseline assessment and up to 4 follow-up assessments approximately every 3 years. Mixture modeling simultaneously determined trajectories of comorbid PTSD and MDD symptoms. Multinomial regression determined factors associated with latent class membership. RESULTS: Four distinct classes (chronic, relapse, gradual recovery, and rapid recovery) described symptom trajectories of PTSD/MDD. Membership in the chronic class was associated with older age, service branch, deployment with combat, anxiety, physical assault, disabling injury/illness, bodily pain, high levels of somatic symptoms, and less social support. CONCLUSIONS: Comorbid PTSD/MDD symptoms tend to move in tandem, and, although the largest class remitted symptoms, almost 25% of participants reported chronic comorbid symptoms across all time points. Results highlight the need to assess comorbid conditions in the context of PTSD. Future research should further evaluate the chronicity of comorbid symptoms over time.

Posttraumatic Stress Disorder Symptom Association With Subsequent Risky and Problem Drinking Initiation.

OBJECTIVES: Posttraumatic stress disorder (PTSD) and unhealthy alcohol use are commonly associated conditions. It is unknown whether specific symptoms of PTSD are associated with subsequent initiation of unhealthy alcohol use. METHODS: Data from the first 3 enrollment panels (n = 151,567) of the longitudinal Millennium Cohort Study of military personnel were analyzed (2001-2012). Complementary log-log models were fit to estimate whether specific PTSD symptoms and symptom clusters were associated with subsequent initiation of 2 domains of unhealthy alcohol use: risky and problem drinking (experience of 1 or more alcohol-related consequences). Models were adjusted for other PTSD symptoms and demographic, service, and health-related characteristics. RESULTS: Eligible study populations included those without risky (n = 31,026) and problem drinking (n = 67,087) at baseline. In adjusted analyses, only 1 PTSD symptom-irritability/anger-was associated with subsequent increased initiation of risky drinking (relative risk [RR] 1.05, 95% confidence interval [CI] 1.00-1.09) at least 3 years later. Two symptom clusters (dysphoric arousal [RR 1.17, 95% CI 1.11-1.23] and emotional numbing [RR 1.30, 95% CI 1.22-1.40]) and 5 symptoms (restricted affect [RR 1.13, 95% CI 1.08-1.19], sense of foreshortened future [RR 1.12, 95% CI 1.06-1.18], exaggerated startle response [RR 1.07, 95% CI 1.01-1.13], sleep disturbance [RR 1.11, 95% CI 1.07-1.15], and irritability/anger [RR 1.12, 95% CI 1.07-1.17]) were associated with subsequent initiation of problem drinking. CONCLUSIONS: Findings suggest that specific PTSD symptoms and symptom clusters are associated with subsequent initiation of unhealthy alcohol use.

Longitudinal Examination of the Influence of Individual Posttraumatic Stress Disorder Symptoms and Clusters of Symptoms on the Initiation of Cigarette Smoking.

OBJECTIVES: The aim of this study was to determine whether specific individual posttraumatic stress disorder (PTSD) symptoms or symptom clusters predict cigarette smoking initiation. METHODS: Longitudinal data from the Millennium Cohort Study were used to estimate the relative risk for smoking initiation associated with PTSD symptoms among 2 groups: (1) all individuals who initially indicated they were nonsmokers (n = 44,968, main sample) and (2) a subset of the main sample who screened positive for PTSD (n = 1622). Participants were military service members who completed triennial comprehensive surveys that included assessments of smoking and PTSD symptoms. Complementary log-log models were fit to estimate the relative risk for subsequent smoking initiation associated with each of the 17 symptoms that comprise the PTSD Checklist and 5 symptom clusters. Models were adjusted for demographics, military factors, comorbid conditions, and other PTSD symptoms or clusters. RESULTS: In the main sample, no individual symptoms or clusters predicted smoking initiation. However, in the subset with PTSD, the symptoms "feeling irritable or having angry outbursts" (relative risk [RR] 1.41, 95% confidence interval [CI] 1.13-1.76) and "feeling as though your future will somehow be cut short" (RR 1.19, 95% CI 1.02-1.40) were associated with increased risk for subsequent smoking initiation. CONCLUSIONS: Certain PTSD symptoms were associated with higher risk for smoking initiation among current and former service members with PTSD. These results may help identify individuals who might benefit from more intensive smoking prevention efforts included with PTSD treatment.

Factors associated with persistent posttraumatic stress disorder among U.S. military service members and veterans.

BACKGROUND: Posttraumatic stress disorder (PTSD) can have long-term and far-reaching impacts on health and social and occupational functioning. This study examined factors associated with persistent PTSD among U.S. service members and veterans. METHODS: Using baseline and follow-up (2001-2013) questionnaire data collected approximately every 3 years from the Millennium Cohort Study, multivariable logistic regression was conducted to determine factors associated with persistent PTSD. Participants included those who screened positive for PTSD using the PTSD Checklist-Civilian Version at baseline (N = 2409). Participants were classified as having remitted or persistent PTSD based on screening negative or positive, respectively, at follow-up. RESULTS: Almost half of participants (N = 1132; 47%) met criteria for persistent PTSD at the first follow-up; of those, 804 (71%) also screened positive for PTSD at the second follow-up. Multiple factors were independently associated with persistent PTSD in an adjusted model at the first follow-up, including older age, deployment with high combat exposure, enlisted rank, initial PTSD severity, depression, history of physical assault, disabling injury/illness, and somatic symptoms. Among those with persistent PTSD at the first follow-up, additional factors of less sleep, separation from the military, and lack of social support were associated with persistent PTSD at the second follow-up. CONCLUSIONS: Combat experiences and PTSD severity were the most salient risk factors for persistent PTSD. Comorbid conditions, including injury/illness, somatic symptoms, and sleep problems, also played a significant role and should be addressed during treatment. The high percentage of participants with persistent PTSD supports the need for more comprehensive and accessible treatment, especially after separation from the military.

Deportation of non-citizen military veterans: A critical analysis of implications for the right to health.

Military personnel are commonly exposed to health-harming conditions during their service, resulting in higher rates of physical and mental health conditions compared with the general population. In an era of mass deportations, it is notable that non-citizen military veterans are not exempt from deportation. We utilised a human rights framework to conduct a critical analysis of potential health consequences of deportation for U.S. military veterans, identifying three ways in which veterans' rights to health may be constrained through deportation. First, honourably discharged deported veterans may be denied access to free or subsidised Veterans Affairs health services to which they would likely otherwise be entitled. Second, availability of and access to healthcare may be limited for reasons including barriers to enrolling in public insurance schemes, challenges navigating unfamiliar health systems and stigma and discrimination towards deported migrants. Finally, quality of available care may be sub-optimal due to limited expertise in service-related health issues and lack of evidence-based treatment for some health conditions (e.g. substance abuse/dependence). Binational multi-sectoral efforts are necessary to ensure that the rights to health of deported military veterans are adequately protected.

Cross-border injection drug use and HIV and hepatitis C virus seropositivity among people who inject drugs in San Diego, California.

BACKGROUND: The prevalence of HIV and Hepatitis C Virus (HCV) are significantly lower among people who inject drugs (PWID) in San Diego, CA, USA compared with PWID in Tijuana, Mexico, located directly across the border. We investigated associations between cross-border injection drug use (IDU), HIV and HCV seroprevalence and engagement in injecting risk behaviours while on each side of the border. METHODS: Using baseline interviews and serologic testing data from STAHR II, a longitudinal cohort study of PWID in San Diego, bivariate and multivariable logistic regression analyses examined associations between recent (past six months) cross-border IDU and HIV and HCV antibody seropositivity, socio-demographics, drug use characteristics, and participants' connections to, and perceptions about Mexico. Chi-squared tests and McNemar tests examined associations between cross-border IDU and injecting risk behaviours. RESULTS: Of the 567 participants (93% U.S.-born, 73% male, median age 45 years), 86 (15%) reported recent cross-border IDU. Cross-border IDU was not associated with HIV (OR: 0.85, 95% CI: 0.37-1.95) or HCV seropositivity (OR: 1.01, 95% CI: 0.62-1.65). Age, identifying as Hispanic or Latino/a, and being concerned about risk of violence when travelling to Mexico were independently associated with decreased odds of recent cross-border IDU. Injecting cocaine at least weekly, having ever lived in Mexico and knowing PWID who reside in Mexico were associated with increased odds of recent cross-border IDU. PWID who reported cross-border IDU were significantly less likely to engage in receptive needle sharing, equipment sharing, and public injection while in Mexico compared with in San Diego (all p<0.001). CONCLUSION: Prevalence of HIV and HCV infection was similar among PWID who had and had not injected in Mexico, possibly due to practising safer injecting while in Mexico. Research is needed to elucidate contextual factors enabling U.S. PWID to inject safely while in Mexico.

Cold Preparation of Heroin in a Black Tar Market.

BACKGROUND: Black tar heroin is typically prepared for injection with heat which decreases the risk of HIV transmission by inactivating the virus. We received reports that persons who inject drugs (PWID) in Tijuana, Baja California, Mexico, a black tar heroin market, were using only water to dissolve heroin. OBJECTIVES: Because Tijuana abuts San Diego County, CA, United States, we undertook the present analyses to determine the prevalence of this practice among PWID in San Diego, California. METHODS: PWID completed quarterly behavioral assessments and serological testing for blood-borne viruses. Bivariate and multivariable logistic regression models were constructed to assess for individual, social, and structural correlates of preparing heroin without heat within the preceding 6 months. RESULTS: Nearly half of black tar heroin users (149/305) reported they had prepared heroin without heat within 6 months. In multivariable analysis, cold preparation was independently associated with younger age (10 year decrease; AOR = 1.25; 95% CI 1.03, 1.53), more drug injecting acquaintances (per 5 acquaintance increase; AOR = 1.05; 95% CI 1.01, 1.09) and prefilled syringe use (injecting drugs from syringes that are already filled with drugs before purchase; AOR = 1.86; 95% CI 1.14, 3.02). Conclusions/Importance: To our knowledge, this is the first paper to report that PWID living in a black tar heroin market are preparing heroin without heat. Additional research is needed to determine whether this is an endemic practice or PWID are engaging in new forms of drug preparation in response to changes in the environment.

Potential Risks of Ecological Momentary Assessment Among Persons Who Inject Drugs.

BACKGROUND: Ecological momentary assessment (EMA)-which often involves brief surveys delivered via mobile technology-has transformed our understanding of the individual and contextual micro-processes associated with legal and illicit drug use. However, little empirical research has focused on participant's perspective on the probability and magnitude of potential risks in EMA studies. OBJECTIVES: To garner participant perspectives on potential risks common to EMA studies of illicit drug use. METHODS: We interviewed 38 persons who inject drugs living in San Diego (CA) and Philadelphia (PA), United States. They completed simulations of an EMA tool and then underwent a semi-structured interview that systematically explored domains of risk considered within the proposed revisions to the Federal Policy for the Protection of Human Subjects or the "Common Rule." Interviews were transcribed verbatim and coded systematically to explore psychological, physical, social, legal, and informational risks from participation. RESULTS: Participants perceived most risks to be minimal. Some indicated that repetitive questioning about mood or drug use could cause psychological (i.e., anxiety) or behavioral risks (i.e., drug use relapse). Ironically, the questions that were viewed as risky were considered motivational to engage in healthy behaviors. The most cited risks were legal and social risks stemming from participant concerns about data collection and security. IMPORTANCE: Improving our understanding of these issues is an essential first step to protect human participants in future EMA research. We provide a brief set of recommendations that can aid in the design and ethics review of the future EMA protocol with substance using populations.

Prevalence and Correlates of Heroin-Methamphetamine Co-Injection Among Persons Who Inject Drugs in San Diego, California, and Tijuana, Baja California, Mexico.

OBJECTIVE: Although persons who inject drugs (PWID) in the western United States-Mexico border region are known to inject both heroin and methamphetamine, little is known about the prevalence and risks associated with co-injection of this depressant-stimulant combination (also known as "goofball" and "Mexican speedball"). METHOD: Baseline data from parallel cohort studies of PWID conducted concurrently in San Diego, CA, and Tijuana, Mexico, were used to estimate the prevalence and identify correlates of heroin-methamphetamine co-injection. PWID older than 18 years of age who reported injecting illicit drugs in the past month (N = 1,311; 32.7% female) were recruited in San Diego (n = 576) and Tijuana (n = 735) and completed interviewer-administered questionnaires. Bivariate and multivariable logistic regression analyses were used to identify correlates of heroin-meth-amphetamine co-injection. RESULTS: The prevalence of co-injection in the past 6 months was 39.9% overall and was higher in Tijuana (55.8%) than in San Diego (19.8%). In multivariable analyses adjusting for study cohort, distributive syringe sharing, purchasing syringes prefilled with drugs, finding it hard to get new syringes, reporting great or urgent need for treatment, and younger age were independently associated with co-injection. Past-6-month overdose was significantly associated with higher odds of co-injection in San Diego than in Tijuana. CONCLUSIONS: These findings indicate that heroin-methamphetamine co-injection is more common in Tijuana than in San Diego, yet this practice was only associated with overdose in San Diego. Heroin-methamphetamine coinjection was also independently associated with HIV-associated injection risk behaviors. Overdose-prevention interventions should address co-injection of depressants and stimulants.

Factors associated with patterns of mobile technology use among persons who inject drugs.

BACKGROUND: New and innovative methods of delivering interventions are needed to further reduce risky behaviors and increase overall health among persons who inject drugs (PWID). Mobile health (mHealth) interventions have potential for reaching PWID; however, little is known about mobile technology use (MTU) in this population. In this study, the authors identify patterns of MTU and identified factors associated with MTU among a cohort of PWID. METHODS: Data were collected through a longitudinal cohort study examining drug use, risk behaviors, and health status among PWID in San Diego, California. Latent class analysis (LCA) was used to define patterns of MTU (i.e., making voice calls, text messaging, and mobile Internet access). Multinomial logistic regression was then used to identify demographic characteristics, risk behaviors, and health indicators associated with mobile technology use class. RESULTS: In LCA, a 4-class solution fit the data best. Class 1 was defined by low MTU (22%, n = 100); class 2, by PWID who accessed the Internet using a mobile device but did not use voice or text messaging (20%, n = 95); class 3, by primarily voice, text, and connected Internet use (17%, n = 91); and class 4, by high MTU (41%, n = 175). Compared with low MTU, high MTU class members were more likely to be younger, have higher socioeconomic status, sell drugs, and inject methamphetamine daily. CONCLUSION: The majority of PWID in San Diego use mobile technology for voice, text, and/or Internet access, indicating that rapid uptake of mHealth interventions may be possible in this population. However, low ownership and use of mobile technology among older and/or homeless individuals will need to be considered when implementing mHealth interventions among PWID.

Prescription Stimulants and PTSD Among U.S. Military Service Members.

Posttraumatic stress disorder (PTSD) is a prevalent condition among military service members and civilians who have experienced traumatic events. Stimulant use has been postulated to increase the risk of incident PTSD; however, research in this area is lacking. In this study, the association between receipt of prescription stimulants and PTSD was examined in a secondary analysis among active duty U.S. military members (n = 25,971), participating in the Millennium Cohort Study, who completed a baseline (2001-2003) and two follow-up surveys (between 2004-2008). Prescription stimulant data were obtained from the military Pharmacy Data Transaction Service. PTSD was assessed using the PTSD Checklist-Civilian Version and incident PTSD was defined as meeting the criteria at follow-up among those who did not have a history of PTSD at baseline. Overall, 1,215 (4.7%) persons developed new-onset PTSD during follow-up. Receipt of prescription stimulants were significantly associated with incident PTSD, hazard ratio = 5.09, 95% confidence interval [3.05, 8.50], after adjusting for sociodemographic factors, military characteristics, attention-deficit/hyperactivity disorder, baseline mental and physical health status, deployment experiences, and physical/sexual trauma. Findings suggested that prescription stimulants are associated with incident PTSD among military personnel; these data may inform the underlying pathogenesis of and preventive strategies for PTSD.