U.S. military service and the prevalence of metabolic syndrome: Findings from a cross-sectional analysis of the Cooper Center Longitudinal Study, 1979-2013.

U.S. military service confers both health benefits and risks potentially associated with a clustering of cardiovascular risk factors called metabolic syndrome. However, the association between prior military service and metabolic syndrome has not sufficiently been examined. The purpose of the study was to compare the prevalence of metabolic syndrome by prior military service status. Among 42,370 men (887 with prior military service) examined from 1979 to 2013 at the Cooper Clinic (Dallas, TX), we used a cross-sectional study design to examine the association between military service and metabolic syndrome. First, an unadjusted log binomial regression model was performed by regressing the prevalence of metabolic syndrome on prior service. This was followed by performing Kleinbaum's modeling strategy for assessing confounding. The same methodology was used to explore the association between individual metabolic syndrome risk factors and prior service. Prior military service was not significantly associated with the prevalence of metabolic syndrome (PR=0.98, 0.89-1.07). None of the variables explored were identified as confounders. Participants with prior military service had lower prevalence of both elevated levels of triglycerides (PR=0.89, 0.80-0.99) and low levels of high-density lipoprotein-cholesterol (PR=0.78, 0.70-0.88). They had a higher prevalence of elevated resting systolic blood pressure (PR=1.23, 1.12-1.35). However, none of these associations were significant after adjusting for identified confounders: age; cardiorespiratory fitness; and exam year. Study findings indicate that military service was not independently associated with the prevalence of metabolic syndrome or its components. Future research is warranted longitudinally assessing the impact of military service on long-term outcomes.

Completion of Multidisciplinary Treatment for Persistent Postconcussive Symptoms Is Associated With Reduced Symptom Burden.

OBJECTIVE: To investigate the pre- to posttreatment changes in both posttraumatic stress disorder (PTSD) and persistent postconcussive symptoms (PPCSs). SETTING AND PARTICIPANTS: We studied 257 active-duty patients with a history of mild traumatic brain injury (mTBI) who completed multidisciplinary outpatient treatment at Brooke Army Medical Center TBI Clinic from 2008 to 2013. This treatment program included cognitive rehabilitation; vestibular interventions; headache management; and integrated behavioral healthcare to address co-occurring psychiatric conditions such as PTSD, depression, and sleep disturbance. DESIGN: A 1-group; preexperimental, pre- to posttreatment study. MAIN MEASURES: The Neurobehavioral Symptom Inventory (NSI) was used to assess PPCSs, and the PTSD Checklist-Military Version (PCL-M) was used to asses PTSD symptoms. RESULTS: Global PPCS resolution (mean NSI: 35.0 pre vs 23.8 post; P < .0001; d = 0.72) and PTSD symptom resolution (mean PCL-M: 43.2 pre vs 37.7 post; P < .0001; d = 0.34) were statistically significant. Compared with those with only mTBI, patients with mTBI and PTSD reported greater global PPCS impairment both pretreatment (mean NSI: 48.7 vs 27.9; P < .0001) and posttreatment (mean NSI: 36.2 vs 17.4; P < .0001). After adjusting for pretreatment NSI scores, patients with comorbid PTSD reported poorer PPCS resolution than those with mTBI alone (mean NSI: 27.9 pre vs 21.7 post; P = .0009). CONCLUSION: We found a reduction in both self-reported PPCSs and PTSD symptoms; however, future studies are needed to identify specific components of care associated with symptom reduction.

Heat effects among migrant and seasonal farmworkers: a case study in Colorado.

BACKGROUND: Although migrant and seasonal farmworkers are highly vulnerable to ambient heat because of their working conditions, heat effects in this population have been rarely studied. OBJECTIVES: We estimated effects of heat on mean daily counts of clinic visits among migrant and seasonal farmworkers by taking advantage of a unique longitudinal medical records database in the USA. METHODS: We compiled a daily weather and clinic visit data set based on data from a health centre in Colorado for the summer of 2013. A total of 14 481 patients were included in our analysis, including 150 migrant farmworkers and 231 seasonal farmworkers with an average of 3 and 4 visits per day. We used Poisson regression to estimate the associations between heat and daily all-cause or cardiovascular-specific clinic visits among migrant or seasonal farmworkers or other stratified patients. We defined heat effects as the percentage difference in average daily counts of clinic visits, comparing 90-50th centiles of daily mean apparent temperature, a composite index accounting for both temperature and humidity. We conducted a sensitivity analysis to evaluate the impact of adjustment for ozone levels and different heat definitions. RESULTS: Estimates of heat effects on average daily clinic visits among migrant farmworkers were positive (88.0%, 95% CI: 26.2% to 180.0%). We did not observe statistically significant associations between heat and clinic visits among other stratified groups. CONCLUSIONS: Our study appears to be the first to link heat effects with clinic data among migrant and seasonal farmworkers. This research suggests possible significant impact of heat on migrant farmworkers and provides justifications for further studies.

Cardiovascular Disease Risk Factors in Hispanic Adolescents in South Texas.

OBJECTIVES: Despite a national crisis of increased prevalence of obesity and type 2 diabetes mellitus in adolescents, especially among Hispanics, there is a paucity of data on health indicators among farmworker adolescents and their peers. The main aim of this study was to estimate the prevalence of cardiovascular disease risk factors in a population of Hispanic adolescent students in south Texas. The study also aimed to compare the prevalence of these risk factors between students enrolled in the Migrant Education Program (MEP) and other students, and between boys and girls. METHODS: In partnership with the Weslaco (Texas) Independent School District and the Migrant Education Department, a cohort study was conducted from 2007 to 2010 to estimate the prevalence of overall obesity (body mass index ≥85th percentile for age and sex), abdominal obesity (waist circumference ≥75th percentile for age, sex, and ethnicity), acanthosis nigricans (AN), and high blood pressure (HBP; ≥90th percentile for age, height, and sex or systolic/diastolic BP ≥120/80 mm Hg) among MEP students compared with other students from two south Texas high schools. Multilevel logistic regression was used to assess the relation between sex and our main outcomes of interest while accounting for within-school nesting of participants. RESULTS: Among 628 sampled students, 508 (80.9%) completed the consent procedure and participated in the study. Of these, 257 were MEP students and 251 were non-MEP peers. Approximately 96.7% of participants were Hispanic and 50.0% were boys. Analyses of data across the years comparing MEP students and non-MEP students show an average prevalence of 44.8% versus 47.7% for overall obesity, 43.2% versus 43.7% for abdominal obesity, 24.7% versus 24.7% for AN, and 29.2% versus 32.8% for HBP. Across recruitment and follow-up years, the prevalence of overall obesity, abdominal obesity, and HBP was 1.3 to 1.5, 1.2 to 1.8, and 2.9 to 4.6 times higher in boys than in girls, respectively. In contrast, the prevalence of AN varied little by sex. CONCLUSIONS: The high prevalence of cardiovascular risk factors in both groups suggests a compelling need for comprehensive, culturally targeted interventions to prevent future cardiovascular diseases in these high-risk Hispanic adolescents, especially among boys. There were not, however, substantial differences between MEP students and other students. These findings also support the feasibility of conducting future epidemiologic studies among adolescent farmworkers and their families, as well as culturally appropriate school or community-based interventions.

Anxiety and smoking cessation outcomes in alcohol-dependent smokers.

INTRODUCTION: Anxiety-related characteristics, including anxiety sensitivity and trait anxiety, are elevated in individuals with alcohol and nicotine dependence and associated with greater difficulties with quitting smoking. However, little is known about how anxiety-related characteristics are related to smoking cessation outcomes in alcohol-dependent smokers. The present study, part of a larger smoking cessation clinical trial, examined associations between anxiety sensitivity, trait anxiety, nicotine withdrawal symptoms, smoking urges, and smoking cessation outcomes in a sample of 83 alcohol-dependent smokers. METHODS: Participants were enrolled in concurrent alcohol and tobacco treatment as part of a substance-abuse intensive outpatient program. Smoking cessation treatment was administered in a 3-week cognitive-behavioral format that included 8 weeks of open-label nicotine patch treatment. Information on nicotine withdrawal, smoking urges, and CO-confirmed smoking consumption rates was collected at baseline, quit date, end of behavioral treatment, and at a 1-month follow-up. RESULTS: Higher levels of anxiety sensitivity were associated with more smoking urges due to anticipation of negative affect relief at quit date. Higher levels of trait anxiety were associated with more smoking urges due to positive reinforcement and anticipation of relief of negative affect at quit date, as well as more severe nicotine withdrawal symptoms at the end of treatment. Levels of anxiety sensitivity and trait anxiety were not associated with Cox regression survival times to relapse. CONCLUSION: These results indicate that for alcohol-dependent smokers, levels of anxiety sensitivity and trait anxiety are important to consider in the assessment and treatment of nicotine dependence.

Acute occupational injury among adolescent farmworkers from South Texas.

PURPOSE: This combined cross-sectional/cohort study addressed research gaps by estimating the rate of non-fatal occupational injury and identifying potential determinants among a population of adolescent farmworkers who are largely Hispanic and migrant. METHODS: The cohort included 410 farmworkers (aged 13-19 years) attending high school in South Texas along the border with Mexico. Data collection involved a self-administered, Web-based survey that solicited information on demographics, farm work variables including person-time at risk, occupational injury, health status and health risk behaviours. Cox regression was used to identify potential risk factors for non-fatal injury events experienced during a 9-month recall period. RESULTS: Depending on the definition of injury, the rate of non-fatal injury ranged from 27.0-73.6/100 full time equivalents. Variables with an increased and statistically significant HR in an adjusted Cox model included: age groups <15 years-old (5.82) and 16 years-old (4.47), usually sleeping <8 h during the week (2.10), feeling tense, stressed or anxious sometimes/often (2.25), not watching TV (2.65), working around ditches (2.01) and detasseling (2.70). CONCLUSIONS: The high observed rates of non-fatal injury combined with the potential negative consequences and cost of these injuries signifies a compelling need for injury prevention efforts targeting adolescent, Hispanic, farmworkers.

Increasing low risk prostate cancer incidence in United States Air Force servicemen and selection of treatments.

PURPOSE: Periodic Health Assessments have been mandated for United States Air Force servicemen since the mid 1990s. Thus, we determined whether United States Air Force prostate cancer incidence rates increased thereafter and how these tumors segregate into low and intermediate/high risk categories. We also identified treatment choices. MATERIALS AND METHODS: We queried the Department of Defense Automated Central Tumor Registry for prostate cancer diagnosed in United States Air Force servicemen between 1991 and 2008 to determine incidence rates, disease risk category and treatments. RESULTS: Age adjusted rates in white active duty servicemen diagnosed for the most recent period of 2005 to 2008 increased 3-fold relative to the rate in the earliest period of 1991 to 1994. A similar trend was evident in black servicemen. Relative to the Surveillance, Epidemiology and End Results population prostate cancer rates in active duty United States Air Force men between 1995 and 2008 were significantly increased for the 2 racial groups. A significantly greater proportion of active duty servicemen than retirees (62% vs 40%) presented with low risk disease, defined as prostate specific antigen less than 10 ng/ml, Gleason sum less than 7 and clinical stage T1a-T2a. Of those with low risk disease significantly more active duty servicemen elected curative surgery than retirees (93% vs 53%). CONCLUSIONS: Prostate cancer incidence rates in United States Air Force servicemen have increased with time, exceeding rates in the Surveillance, Epidemiology and End Results population. While most cases are characterized as low risk, aggressive management is elected.

Kuru prions and sporadic Creutzfeldt-Jakob disease prions have equivalent transmission properties in transgenic and wild-type mice.

Kuru provides our principal experience of an epidemic human prion disease and primarily affected the Fore linguistic group of the Eastern Highlands of Papua New Guinea. Kuru was transmitted by the practice of consuming dead relatives as a mark of respect and mourning (transumption). To date, detailed information of the prion strain type propagated in kuru has been lacking. Here, we directly compare the transmission properties of kuru prions with sporadic, iatrogenic, and variant Creutzfeldt-Jakob disease (CJD) prions in Prnp-null transgenic mice expressing human prion protein and in wild-type mice. Molecular and neuropathological data from these transmissions show that kuru prions are distinct from variant CJD and have transmission properties equivalent to those of classical (sporadic) CJD prions. These findings are consistent with the hypothesis that kuru originated from chance consumption of an individual with sporadic CJD.

Prostate cancer incidence in U.S. Air Force aviators compared with non-aviators.

INTRODUCTION: Several studies investigating whether prostate cancer incidence is elevated in aviators both in the civilian and military sectors have yielded inconsistent findings. Most investigations have compared aviators to the general population. Instead, our study compared prostate cancer incidence rates among officer aviators and non-aviators in the U.S. Air Force (USAF) to reduce confounding by socioeconomic status and frequency of medical exams. METHODS: This retrospective analysis ascertained prostate cancer cases using the Automated Cancer Tumor Registry of the Department of Defense linked to personnel records from the USAF Personnel Center to identify aviators and non-aviators. Survival analysis using the Cox Proportional Hazards model allowed comparison of prostate cancer incidence rates in USAF aviators and non-aviators. RESULTS: After adjustment for age and race, the hazards ratio for prostate cancer incidence comparing aviators with non-aviators was 1.15 (95% confidence interval, 0.85-1.44). Neither prostate cancer incidence nor time to diagnosis differed significantly between the two groups. CONCLUSION: Our study compared prostate cancer rates in aviators with a reference group of non-aviators similar in socio-economic level and frequency of exams. When compared to this internal reference group the risk of prostate cancer in USAF officer aviators appeared similar with no significant excess.

The medical analysis of child sexual abuse images.

Analysis of child sexual abuse images, commonly referred to as pornography, requires a familiarity with the sexual maturation rating of children and an understanding of growth and development parameters. This article explains barriers that exist in working in this area of child abuse, the differences between subjective and objective analyses, methods used in working with this form of contraband, and recommendations that analysts document their findings in a format that allows for verbal descriptions of the images so that the content will be reflected in legal proceedings should there exist an aversion to visual review. Child sexual abuse images are a digital crime scene, and analysis requires a careful approach to assure that all victims may be identified.

A complete Protocadherin-19 ectodomain model for evaluating epilepsy-causing mutations and potential protein interaction sites.

Cadherin superfamily members play a critical role in differential adhesion during neurodevelopment, and their disruption has been linked to several neurodevelopmental disorders. Mutations in protocadherin-19 (PCDH19), a member of the δ-protocadherin subfamily of cadherins, cause a unique form of epilepsy called PCDH19 clustering epilepsy. While PCDH19 and other non-clustered δ-protocadherins form multimers with other members of the cadherin superfamily to alter adhesiveness, the specific protein surfaces responsible for these interactions are unknown. Only portions of the PCDH19 extracellular domain structure had been solved previously. Here, we present a structure of the missing segment from zebrafish Protocadherin-19 (Pcdh19) and create a complete ectodomain model. This model shows the structural environment for 97% of disease-causing missense mutations and reveals two potential surfaces for intermolecular interactions that could modify Pcdh19's adhesive strength and specificity.

A pilot study of symptoms of neurotoxicity and injury among adolescent farmworkers in Starr County, Texas.

Little is known regarding the relationship between neurotoxicity symptoms and injury, particularly among adolescent farmworkers. This pilot study utilized logistic regression to analyze injury prevalence in relation to self-reported symptoms of neurotoxicity among adolescent farmworkers along the US-Mexico border in Texas. Respondents reporting at least five symptoms had 8.75 (95% CI, 1.89-40.54) times the prevalence of injury compared with those reporting zero or one symptom. Significant associations were observed for six items: trouble remembering things, family noticing memory loss, making notes, irritated for no reason, heart pounding, and tingling. This pilot study suggests a relationship between symptoms of neurotoxicity and injury among adolescent farmworkers, supporting the need for more rigorous investigations.

Influence of Work on Elevated Blood Pressure in Hispanic Adolescents in South Texas.

Literature supports an association between work and cardiovascular disease in adults. The objective of this study was to examine the relationship between current work status and elevated blood pressure in Hispanic adolescents. Participants were students in Hidalgo County, located along the Texas-Mexico border. Participants enrolled in the cohort study in ninth grade with assessments completed once a year for up to three years. Participants completed a self-report survey, while staff measured height, weight, waist circumference, blood pressure, and were screened for acanthosis nigricans. A generalized linear regression model with a logit link function was constructed to assess current work status and elevated blood pressure. Of the 508 participants, 29% had elevated blood pressure, which was associated with being male and other chronic disease indicators (e.g., acanthosis nigricans, overweight/obesity). The mean probability for elevated blood pressure was higher among currently working adolescents compared to those who were not. Findings were statistically significant (p < 0.05) at baseline. The findings illustrate that a large proportion of adolescents along the Texas-Mexico border may have elevated blood pressure and that working may be associated with it. Subsequent research is needed to confirm these findings, as well as to identify the mechanism for how work may increase hypertension in adolescents.

A simple classical model for predicting onset crystallization temperatures on curved substrates and its implications for phase transitions in confined volumes.

For small confinement volumes, phase transition temperatures are determined by the scarcity of the crystallizing material, rather than the magnitude of the energy barrier, as the supply of molecules undergoing the phase transition can be depleted before a stable nucleus is attained. We show this for the case of crystallization from the melt and from the solution by using a simple model based on an extended classical nucleation theory. This has important implications because it enables a simple and direct measurement of the critical nucleus size in crystallization. It also highlights that predicting the observable melting points of nanoparticles by using the Gibbs-Thomson equation can lead to substantial errors.

Severe back pain among farmworker high school students from Starr County, Texas: baseline results.

PURPOSE: This cohort study is among the first to estimate the prevalence of and examine potential risk factors for severe back pain (resulting in medical care, 4+ hours of time lost, or pain lasting 1+ weeks) among adolescent farmworkers. These youth often perform tasks requiring bent/stooped postures and heavy lifting. METHODS: Of 2536 students who participated (response rate across the three public high schools, 61.2% to 83.9%), 410 students were farmworkers (largely Hispanic and migrant). Students completed a self-administered Web-based survey including farm work/nonfarm work and back-pain items relating to a 9-month period. RESULTS: The prevalence of severe back pain was 15.7% among farmworkers and 12.4% among nonworkers. The prevalence increased to 19.1% among farm workers (n = 131) who also did nonfarm work. A multiple logistic regression for farmworkers showed that significantly increased adjusted odds ratios for severe back pain were female sex (4.59); prior accident/back injury (9.04); feeling tense, stressed, or anxious sometimes/often (4.11); lifting/carrying heavy objects not at work (2.98); current tobacco use (2.79); 6+ years involved in migrant farm work (5.02); working with/around knives (3.87); and working on corn crops (3.40). CONCLUSIONS: Areas for further research include ergonomic exposure assessments and examining the effects of doing farm work and nonfarm work simultaneously.

Phenotypic heterogeneity in inherited prion disease (P102L) is associated with differential propagation of protease-resistant wild-type and mutant prion protein.

Inherited prion diseases are caused by PRNP coding mutations and display marked phenotypic heterogeneity within families segregating the same pathogenic mutation. A proline-to-leucine substitution at prion protein (PrP) residue 102 (P102L), classically associated with the Gerstmann-Sträussler-Scheinker (GSS) phenotype, also shows marked clinical and pathological heterogeneity, including patients with a Creutzfeldt-Jakob disease (CJD) phenotype. To date, this heterogeneity has been attributed to temporal and spatial variance in the propagation of distinct protease-resistant (PrP(Sc)) isoforms of mutant PrP. Here, using a monoclonal antibody that recognizes wild-type PrP, but not PrP 102L, we reveal a spectrum of involvement of wild-type PrP(Sc) in P102L individuals. PrP(Sc) isoforms derived from wild-type and mutant PrP are distinct both from each other and from those seen in sporadic and acquired CJD. Such differential propagation of disease-related isoforms of wild-type PrP and PrP 102L provides a molecular mechanism for generation of the multiple clinicopathological phenotypes seen in inherited prion disease.

Skin Colour, Perception of Racism and Depression among Adolescents in Urban Brazil.

BACKGROUND: The relation between race, ethnicity and health has been recognised as having an important role in the understanding of social inequalities in health. In Brazil, miscegenation (the mixing of different ethnicities or races, especially in marriage) is recognised as a sign of racial tolerance, but individuals with black skin colour have poorer social and health indicators than whites. The hypothesis that perceived racial discrimination is associated with depression and depressive symptoms among adolescents living in a Brazilian urban area is analysed, taking into consideration sociodemographic variables, socioeconomic status and skin colour. METHOD: This paper presents results from a cross-sectional study carried out with a random one-stage cluster sampling of households in the city of Salvador, Bahia, Brazil. The study population comprises 973 individuals from 10 to 21 years of age who answered questionnaires about racial discrimination, socio-demographic and health-related variables. Major depression according to DSM-IV criteria was assessed using a validated Portuguese version of the Patient Health Questionnaire (PHQ). The overall prevalence of major depression was estimated as 10.4%. RESULTS: No statistically significant differences were found for prevalence of major depression or any depressive symptom according to skin colour (Black versus non-Black). However, adolescents who reported racial discrimination were more likely to have major depression, even after adjustment for age, sex, socioeconomic status, skin colour and self-esteem (Adjusted Prevalence ratio = 2.00, 95% Confidence Interval: 1.37-2.97). Low self-esteem was not associated with racial discrimination. CONCLUSION: Depression among adolescents is a common disorder. Skin colour, a biological component of ethnic differences, was not a factor associated with depression or depressive symptoms. Instead, the perception of racial discrimination was a strong potential risk factor for major depression in this population group, which needs to be addressed in further studies and considered in preventive and mental health care programs.

"The Only Thing I Wish I Could Change Is That They Treat Us Like People and Not Like Animals": Injury and Discrimination Among Latino Farmworkers.

OBJECTIVE: This article describes how perceived discrimination shapes the way Latino farmworkers encounter injuries and seek out treatment. METHODS: After 5 months of ethnographic fieldwork, 89 open-ended, semistructured interviews were analyzed. NVivo was used to code and qualitatively organize the interviews and field notes. Finally, codes, notes, and co-occurring dynamics were used to iteratively assess the data for major themes. RESULTS: The primary source of perceived discrimination was the "boss" or farm owner. Immigrant status was also a significant influence on how farmworkers perceived the discrimination. Specifically, the ability to speak English and length of stay in the United States were related to stronger perceptions of discrimination. Finally, farm owners compelled their Latino employees to work through their injuries without treatment. CONCLUSIONS: This ethnographic account brings attention to how discrimination and lack of worksite protections are implicated in farmworkers' injury experiences and suggests the need for policies that better safeguard vulnerable workers.

A Randomized Trial of Contingency Management for Smoking Cessation During Intensive Outpatient Alcohol Treatment.

INTRODUCTION: This randomized clinical trial was designed to evaluate the efficacy of contingency management (CM) for smoking cessation for smokers with alcohol abuse or dependence delivered concurrently with intensive outpatient alcohol treatment. The study also explored the indirect effects of CM smoking treatment and smoking cessation on alcohol and drug use outcomes. METHODS: Alcohol abuse/dependent smokers were randomized to cognitive behavioral therapy plus nicotine replacement therapy plus contingency management (CBT+NRT+CM) or to cognitive behavior therapy plus nicotine replacement therapy (CBT+NRT) delivered concurrent with a three-week intensive outpatient alcohol treatment program. RESULTS: Participants in the CBT+NRT+CM condition were significantly more likely to be cigarette abstinent at the end of treatment (χ2(1)=8.48, p=.004) with approximately double the carbon monoxide confirmed quit rate (60%) compared with the CBT+NRT condition (29%). At the one-month and six-month time-points there were nonsignificant differences in smoking abstinence outcomes by condition. Smoking treatment condition did not directly affect alcohol abstinence outcomes, but we observed an indirect effect of smoking treatment on alcohol and drug abstinence at one-month follow-up that was mediated by smoking cessation at the end of treatment. CONCLUSIONS: Adding CM to an evidence-based smoking cessation treatment that included medication and behavioral counseling doubled the quit rate at the end of treatment. This finding provides strong evidence for the efficacy of CM for helping alcohol dependent smokers reach the milestone of initial smoking abstinence.