Estimated Pulse Wave Velocity is Associated with a Higher Risk of Dementia in the Health and Retirement Study.

BACKGROUND: In this paper, we use the Health and Retirement Study (HRS) to examine the relationship between an estimated measure of pulse wave velocity (ePWV) and cognitive impairment with no dementia and dementia, respectively. METHODS: We modeled the relationship between ePWV and cognitive status in 2006/2008 using data from 8,492 men and women (mean age 68.6 years) controlling for age, blood pressure, sociodemographic and socioeconomic characteristics (sex, race and ethnicity, education, income, wealth), health behaviors (smoking and physical activity), body mass index (BMI), health status and related medication use (history of cardiovascular disease, diabetes, and stroke), and cerebrovascular disease (CVD)-related biomarkers (C-reactive protein, cystatin-C, hemoglobin A1c, total cholesterol, high-density lipoprotein [HDL] cholesterol). We assess cognitive function with the 27-item Langa-Weir Telephone Interview for Cognitive Status (TICS) scale. ePWV is derived from an equation based on participant age and resting blood pressure. RESULTS: In a model that controlled for the constituent components of ePWV (age, age squared, systolic and diastolic blood pressure), ePWV is associated with increased odds of having cognitive impairment with no dementia (OR=2.761) and dementia (OR=6.344) relative to a group with no cognitive impairment or dementia. After controlling for the constituent components of ePWV, sociodemographic and socioeconomic characteristics, health status and medication use, health behaviors, BMI, and CVD-related biomarkers, ePWV remains significantly associated with dementia (OR=3.969) but not cognitive impairment with no dementia (OR=1.782). CONCLUSIONS: These findings suggest that ePWV may be a novel research tool and biomarker of vascular aging that can be used in large, population-representative studies to examine cognitive aging and dementia risk.

Hypertension at the nexus of veteran status, psychiatric disorders, and traumatic brain injury: Insights from the 2011 Behavioral Risk Factor Surveillance System.

Variable military service-related experiences, such as combat exposure, psychiatric disorders (PD), and traumatic brain injuries (TBI), may differentially affect the likelihood of having health care professional-identified high blood pressure (i.e., hypertension). PURPOSE: Compare the odds of self-reported hypertension among non-combat and combat veterans with and without PD/TBI to non-veterans and each other. METHODS: We used data from men from the 2011 Behavioral Risk Factor Surveillance System and distinguished: non-veterans (n = 21,076); non-combat veterans with no PD/TBI (n = 3,150); combat veterans with no PD/TBI (n = 1,979); and veterans (combat and non-combat) with PD and/or TBI (n = 805). Multivariable, hierarchical logistic regression models included exogenous demographic, socioeconomic attainment and family structure, health behavior and conditions, and methodological control variables. RESULTS: One-third of men reported having been told at least once by a medical professional that they had high blood pressure. Bivariate analyses indicated that each veteran group had a higher prevalence of self-reported hypertension than non-veterans (design-based F = 45.2, p<0.001). In the fully adjusted model, no statistically significant differences in the odds of self-reported hypertension were observed between non-veterans and: non-combat veterans without PD/TBI (odds ratio [OR] = 0.92); combat veterans without PD/TBI (OR = 0.87); veterans with PD and/or TBI (OR = 1.35). However, veterans with PD and/or TBI had greater odds of reporting hypertension than both combat and non-combat veterans without PD/TBI (p<0.05). DISCUSSION: Military service-related experiences were differentially associated with a survey-based measure of hypertension. Specifically, veterans self-reporting PD and/or TBI had significantly higher odds of self-reporting hypertension (i.e., medical provider-identified high blood pressure).

Estimated pulse wave velocity as a measure of vascular aging.

BACKGROUND: Carotid-femoral pulse wave velocity (cfPWV), the referent measure of aortic stiffness, is an established measure of vascular aging. In studies where cfPWV cannot be measured, alternative methods are needed to help promote research on vascular aging. This study examines the construct validity of a measure of PWV estimated from age and blood pressure (ePWV). The specific aims of the study are to: 1) explore the strength of association between ePWV, cfPWV, and other established measures of vascular aging; 2) examine the sensitivity and specificity of elevated ePWV (≥10m/s) in relation to elevated cfPWV (≥10m/s). METHODS: We measured cfPWV in two-hundred and fifty-two adults (mean age 57±12 years, 48% female) and calculated each participant's ePWV from their age and brachial blood pressure. Additional measures of vascular aging included: carotid intima-media thickness (cIMT); carotid stiffness measured as elastic modulus (cEp); and carotid augmentation index (cAIx). RESULTS: The correlations between cfPWV and measures of vascular aging were: cEp (r = 0.36), cIMT (r = 0.49), and cAIx (r = 0.04). The correlations between ePWV and measures of vascular aging were: cEp (r = 0.45), cIMT (r = 0.60), and cAIx (r = 0.24). The correlation between ePWV and cfPWV was (r = 0.67). The sensitivity and specificity of elevated ePWV (≥ 10 m/s) for concomitantly identifying high cfPWV (≥ 10 m/s) were 85.4% and 73.0% respectively. CONCLUSION: ePWV is associated with established measures of vascular aging, such as carotid thickness, carotid stiffness and carotid augmentation index. ePWV may be a useful tool to help promote research on vascular aging.

Risk Factors Explaining Military Deaths From Suicide, 2008-2017:A Latent Class Analysis.

Military suicide prevention efforts would benefit from population-based research documenting patterns in risk factors among service members who die from suicide. We use latent class analysis to analyze patterns in identified risk factors among the population of 2660 active-duty military service members that the Department of Defense Suicide Event Report (DoDSER) system indicates died by suicide between 2008 and 2017. The largest of five empirically derived latent classes was primarily characterized by the dissolution of an intimate relationship in the past year. Relationship dissolution was common in the other four latent classes, but those classes were also characterized by job, administrative, or legal problems, or mental health factors. Distinct demographic and military-status differences were apparent across the latent classes. Results point to the need to increase awareness among mental health service providers and others that suicide among military service members often involves a constellation of potentially interrelated risk factors.

Estimated Pulse Wave Velocity and All-Cause Mortality: Findings From the Health and Retirement Study.

Background and Objectives: The gold standard method for the assessment of vascular aging is carotid-femoral pulse wave velocity (cfPWV). cfPWV can be estimated from 2 commonly assessed clinical variables-age and blood pressure. This analysis uses data from the Health and Retirement Study to examine the relationship between estimated pulse wave velocity (ePWV) and mortality among 9,293 middle age and older adults. Research Design and Methods: Cox proportional hazard models were used to predict mortality occurring over a 10- to 12-year period. Controls were included for sociodemographic characteristics (age, gender, race, ethnicity, wealth, income, and education), health status (history of cardiovascular disease [CVD], diabetes, and stroke and related medication use), health behaviors (smoking, physical activity, and body mass index), and CVD-related biomarkers (systolic and diastolic blood pressure, C-reactive protein, cystatin c, hemoglobin A1c, total cholesterol, and high-density lipoprotein cholesterol). Results: By 2018, 26.19% of the weighted analytic sample were reported as deceased. In the fully specified models that control for age, age-squared, systolic and diastolic blood pressure, sociodemographic variables, health status and behaviors, and biomarkers, ePWV was associated with a greater likelihood of mortality. Discussion and Implications: An estimate of PWV derived from age and blood pressure is independently associated with an increased likelihood of death in a representative sample of middle age and older adults in the United States.

Attention deficit hyperactivity disorder and the age pattern of adult mortality.

We draw upon the life-course perspective and examine whether Attention Deficit Hyperactivity Disorder (ADHD) moderates the age pattern of adult mortality using data from the 2007 and 2012 National Health Interview Survey Sample Adult File linked to National Death Index data through 2015. Overall, 7.0% of respondents died by 2015. Discrete-time hazard analysis indicates that the log odds of mortality were significantly lower among 18 and 19 year old adults ever diagnosed with ADHD and significantly higher among 46 to 64 year old adults ever diagnosed with ADHD, with a crossover occurring at age 33. Results were similar among men and women. It is not known specifically which risks drive changes in the risk of mortality documented among persons with ADHD during the transition to adulthood, the increased risk of mortality in midlife, or whether some risks operate more or less at particular ages. Additional research can lead to targeted, age- and life-course stage-focused interventions for specific risks and contribute to the reduction of ADHD-related mortality.

Perceived access to PrEP as a critical step in engagement: A qualitative analysis and discrete choice experiment among young men who have sex with men.

Young Men who have Sex with Men (MSM) continue to face disproportionate HIV risk. Despite its well accepted role in HIV prevention, pre-exposure prophylaxis (PrEP) uptake remains below desired goals. Systemic barriers to PrEP access, including insurance complexity, cost, and wait times to start PrEP may contribute to low PrEP engagement. We conducted in-depth interviews and designed a discrete choice experiment (DCE) to assess preferences for and barriers to PrEP access in the United States. METHODS: We conducted in-depth interviews with 18 MSM aged 18-30 years old who were not on PrEP and created a DCE based on the results. For the DCE, a convenience sample of young MSM in the United States who reported recent condomless anal sex was recruited through social media applications. Consenting participants provided sociodemographic information and responded to a series of 10 choice tasks about PrEP access. Preferences were analyzed utilizing marginal willingness-to-pay (mWTP) methods. RESULTS: In-depth interviews revealed preferences for highly effective PrEP and concerns about barriers to access due to insurance coverage and privacy. The online DCE was completed by 236 eligible MSM aged 18-30. The most-preferred PrEP package-with all elements significantly preferred over other options-was insurance covered, could be maintained confidential from parents and employers, was available immediately, and had an online option. Need to take out new insurance or add a supplemental insurance in order to cover PrEP significantly detracted from willingness to pay for a PrEP program. Attributes most associated with willingness to pay for PrEP were PrEP being covered by an insurance the client already has and insurance coverage that was private. CONCLUSIONS: Young MSM at high risk for HIV in the United States who are not currently on PrEP showed strong preferences for PrEP options that were covered by insurance and could be kept confidential from parents and employers. Lack of these options may present major barriers to PrEP access among young MSM who are at particularly high risk. Rapid access to PrEP, as well as the option of receiving some care online, may also enhance PrEP uptake.

Depression and mental health service use among 12-17 year old U.S. adolescents: Associations with current parental and sibling military service.

OBJECTIVE: To examine whether having a parent and/or a sibling currently serving in the military is associated with major depression and use of mental health services among 12-17 year old adolescents in the United States. METHOD: Descriptive and multivariate logistic regression analyses are conducted using pooled data from the 2016-2019 National Survey of Drug Use and Health (NSDUH). Analyses are weighted and standard errors are adjusted for the complex sampling design. RESULTS: Adolescents are more likely to have a sibling than a parent currently serving in the military. Having a sibling currently in the military increases the likelihood of having a lifetime and a past-year major depressive episode (MDE), but not a past-year MDE with severe role impairment or use of mental health services. Having a parent in the military is not associated with any measure of MDE, but increases use of specialty outpatient, specialty inpatient/residential, and non-specialty mental health services net of MDE and sociodemographic controls. CONCLUSION: Considerable attention has focused on risk and resilience among the dependent children of current service members. A better understanding of how the current military service experiences of siblings, as well as parents, influences related adolescents' mental health, mental health care service use, substance use, and health behaviors has the potential to contribute to programs and interventions that can enhance the well-being of youth with intra-generational, as well as inter-generational, connections to the military. Adolescents who have a sibling currently serving in the military are an at-risk population for MDE and potentially other mental and behavioral health problems.

'It's history in the making all around us': examining COVID-19 through the lenses of HIV and epidemic history.

Research increasingly considers how collective narratives/experiences of HIV influence understandings of and responses to COVID-19 among men who have sex with men and how these discussions articulate with the larger literature on the social significance of epidemics. Drawing on interviews with 30 men who have sex with men, as well as discussion of epidemics as dramaturgical events, this study aimed to determine how men living in the USA make sense of COVID-19 in the light of their collective knowledge and/or memories of the HIV pandemic. Participants experienced progressive revelations regarding COVID-19's seriousness and constructed frameworks with which to manage the unpredictability of infection. Participants also believed that the initial public response to COVID-19 on the part of the US federal government, health officials and the scientific community, although inadequate, was stronger and more extensive than the response had been to HIV. As communities and the USA negotiated their pandemic responses, participants negotiated their own personal responses with incomplete, uncertain, dynamic and conflicting information. This study provides evidence regarding the social organisation of a contemporary pandemic and how individuals perceive and guard against risk, assign responsibility for virus transmission and acquisition, and navigate the threat of a potentially deadly infection.

Community-Driven Methods for Open and Reproducible Software Tools for Analyzing Datasets from Atom Probe Microscopy.

Atom probe tomography, and related methods, probe the composition and the three-dimensional architecture of materials. The software tools which microscopists use, and how these tools are connected into workflows, make a substantial contribution to the accuracy and precision of such material characterization experiments. Typically, we adapt methods from other communities like mathematics, data science, computational geometry, artificial intelligence, or scientific computing. We also realize that improving on research data management is a challenge when it comes to align with the FAIR data stewardship principles. Faced with this global challenge, we are convinced it is useful to join forces. Here, we report the results and challenges with an inter-laboratory call for developing test cases for several types of atom probe microscopy software tools. The results support why defining detailed recipes of software workflows and sharing these recipes is necessary and rewarding: Open source tools and (meta)data exchange can help to make our day-to-day data processing tasks become more efficient, the training of new users and knowledge transfer become easier, and assist us with automated quantification of uncertainties to gain access to substantiated results.

Same-Sex Sexuality and the Risk of Divorce: Findings from Two National Studies.

Despite symbolic linkages between heterosexuality and marriage, and a pervasive heteronormative ideology of romantic love, little population-representative research examines whether same-sex sexuality - desire/attraction, behavior, and gay, lesbian, or bisexual identity - increases the likelihood of divorce from an different-sex spouse. We examine this association using data from the 1992 National Health and Social Life Survey and the 2011-2013 National Survey of Family Growth. In both sub-studies, multivariate logistic regression analyses indicate that same-sex sexuality reduces the odds of ever marrying. However, among the once-married, same-sex desire/attraction, sexual behavior, and gay, lesbian, or bisexual identity respectively increase the odds of different-sex divorce net of demographic and early-life factors. Same-sex sexuality puts a brake on divorce by preventing some different-sex marriages that would ultimately end in divorce, but is associated with an increase risk of different-sex divorce among once-married individuals.

Self-Reported ADHD and Adult Health in the United States.

Objective: Informed by a social determinants of health framework, we investigate the relationship between self-reported ADHD diagnosis status and adult health, and whether observed associations are attenuated by biomedical and socioeconomic factors. Method: Using 2007 National Health Interview Survey data (N = 19,104), we present multivariate logistic regression analyses of associations between self-reported ADHD diagnosis status and five adult health outcomes. Results: ADHD diagnosis was significantly associated with higher odds of injury, physical health conditions, functional limitations, fair/poor health, and psychological distress in fully specified models (adjusted odds ratios [AORs] = 1.62-2.36). Inclusion of controls for exogenous demographic characteristics, psychiatric comorbidities and health behaviors, and adult social and economic statuses attenuated but did not eliminate observed associations between ADHD and poorer adult health. Conclusion: Research on adult health outcomes for those with ADHD should include consideration of the mechanisms by which a diagnosis of ADHD leads to cumulative social disadvantages that independently contribute to poorer health outcomes.

Cohort Change in the Prevalence of ADHD Among U.S. Adults: Evidence of a Gender-Specific Historical Period Effect.

Objective: To document inter- and intra-cohort changes in adult ADHD and examine whether changes vary by gender. Method: We analyze data from the 2007 and 2012 U.S. National Health Interview Survey. Results: The prevalence of ADHD among adults aged 18 to 64 years increased from 3.41% in 2007 to 4.25% in 2012. As expected, patterns of inter- and intra-cohort change varied by gender. At younger ages, inter-cohort gender differences are more distinct due to a spike in prevalence among boys/men born in or after 1980. Consistent with a gender-specific historical period effect, recent intra-cohort increases among women have narrowed the gender gap. Conclusion: The gender gap in the prevalence of ADHD among adults decreased by 31.1% from 2007 to 2012 due to increased prevalence among adult women of all ages. We discuss these results in relation to diagnostic practice, adult health and well-being, data limitations and needs, and directions for future research.

Solving Peak Overlaps for Proximity Histogram Analysis of Complex Interfaces for Atom Probe Tomography Data.

Atom probe tomography is a powerful tool for investigating nanostructures such as interfaces and nanoparticles in material science. Advanced analysis tools are particularly useful for analyzing these nanostructures characterized very often by curved shapes. However, these tools are very limited for complex materials with non-negligible peak overlaps in their respective mass-to-charge ratio spectra. Usually, an analyst solves peak overlaps in the bulk regions, but the behavior at interfaces is rarely considered. Therefore, in this work, we demonstrate how the proximity histogram generated for a specific interface can be corrected by using the natural abundances of isotopes. This leads to overlap-solved proximity histograms with a resolution of up to 0.1 nm. This work expands on previous work that showed the advantage of a maximum-likelihood peak overlap solving. The corrected proximity histograms together with the maximum-likelihood peak overlap algorithm were implemented in a user-friendly software suite called EPOSA.

Observation of Transient and Asymptotic Driven Structural States of Tungsten Exposed to Radiation.

Combining spatially resolved x-ray Laue diffraction with atomic-scale simulations, we observe how ion-irradiated tungsten undergoes a series of nonlinear structural transformations with increasing radiation exposure. Nanoscale defect-induced deformations accumulating above 0.02 displacements per atom (dpa) lead to highly fluctuating strains at ∼0.1 dpa, collapsing into a driven quasisteady structural state above ∼1 dpa. The driven asymptotic state is characterized by finely dispersed vacancy defects coexisting with an extended dislocation network and exhibits positive volumetric swelling, due to the creation of new crystallographic planes through self-interstitial coalescence, but negative lattice strain.

Processing APT Spectral Backgrounds for Improved Quantification.

We describe a method to estimate background noise in atom probe tomography (APT) mass spectra and to use this information to enhance both background correction and quantification. Our approach is mathematically general in form for any detector exhibiting Poisson noise with a fixed data acquisition time window, at voltages varying through the experiment. We show that this accurately estimates the background observed in real experiments. The method requires, as a minimum, the z-coordinate and mass-to-charge-state data as input and can be applied retrospectively. Further improvements are obtained with additional information such as acquisition voltage. Using this method allows for improved estimation of variance in the background, and more robust quantification, with quantified count limits at parts-per-million concentrations. To demonstrate applications, we show a simple peak detection implementation, which quantitatively suppresses false positives arising from random noise sources. We additionally quantify the detectability of 121-Sb in a standardized-doped Si microtip as (1.5 × 10−5, 3.8 × 10−5) atomic fraction, α = 0.95. This technique is applicable to all modes of APT data acquisition and is highly general in nature, ultimately allowing for improvements in analyzing low ionic count species in datasets.

Morphological analysis of 3d atom probe data using Minkowski functionals.

We present a morphological analysis of atom probe data of nanoscale microstructural features, using methods developed by the astrophysics community to describe the shape of superclusters of galaxies. We describe second-phase regions using Minkowski functionals, representing the regions' volume, surface area, mean curvature and Euler characteristic. The alloy data in this work show microstructures that can be described as sponge-like, filament-like, plate-like, and sphere-like at different concentration levels, and we find quantitative measurements of these features. To reduce user decision-making in constructing isosurfaces and to enhance the accuracy of the analysis a maximum likelihood based denoising filter was developed. We show that this filter performs significantly better than a simple Gaussian smoothing filter. We also interpolate the data using natural cubic splines, to refine voxel sizes and to refine the surface. We demonstrate that it is possible to find a mathematically well-defined, quantitative description of microstructure from atomistic datasets, to sub-voxel resolution, without user-tuneable parameters.

The Influence of Military Service Experiences on Current and Daily Drinking.

Background: An extensive public health literature associates military service with increased alcohol consumption and problematic drinking. However, few well-controlled population-based studies compare alcohol use among nonveterans and veterans with diverse military service experiences, and no such study examines everyday drinking. Methods: We use population-representative data from the 2010 and 2011 Behavioral Risk Factor Surveillance System and distinguish four groups of men: nonveterans; non-combat veterans without a psychiatric disorder (PD) or traumatic brain injury (TBI); combat veterans without a PD or TBI; and veterans (non-combat and combat combined) with a PD and/or TBI. We estimate hierarchical multivariate logistic regression models of current drinking (N = 21,947) and daily drinking (among current drinkers; N = 11,491). Results from supplemental analyses are discussed. Results: Relative to nonveterans, non-combat veterans with no PD or TBI and veterans with a PD and/or TBI, respectively, but not combat veterans with no PD or TBI, are more likely to be current drinkers. Among current drinkers, non-combat and combat veterans with no PD or TBI, respectively, are less likely than nonveterans to be daily drinkers. Conversely, among current drinkers, veterans with a PD and/or TBI are more likely to be daily drinkers than nonveterans, non-combat veterans with no PD or TBI, and combat veterans with no PD or TBI. Conclusion: We document heterogeneous and countervailing influences of military service experiences on current and daily drinking. Results indicate that harmful military service experience may be associated with an increased risk of current, moderate daily drinking, which may represent a form of self-medication.

Exploitation of thermal gradients for investigation of irradiation temperature effects with charged particles.

The effects of radiation damage on materials are strongly dependant on temperature, making it arguably the most significant parameter of concern in nuclear engineering. Owing to the challenges and expense of irradiating and testing materials, material property data is often limited to few irradiation conditions and material variants. A new technique has been developed which enables the investigation of radiation damage of samples subject to a thermal gradient, whereby a wealth of data over a range of irradiation temperatures is produced from a single irradiation experiment. The results produced are practically inaccessible by use of multiple conventional isothermal irradiations. We present a precipitation-hardened copper alloy (CuCrZr) case-study irradiated with a linear temperature gradient between 125 and 440 °C. Subsequent micro-scale post irradiation characterisation (nanoindentation, transmission electron microscopy and atom probe tomography) highlight the capability to observe mechanical and microstructural changes over a wide range of irradiation temperatures. We observed irradiation-softening in CuCrZr that did not occur due to irradiation-enhanced aging of the Cr-precipitates. Excellent reproducibility of the new technique was demonstrated and replicated irradiation-hardening data from several isothermal neutron irradiation studies. Our new technique provides this data at a fraction of the time and cost required by conventional irradiation experiments.

Quantifying Uncertainty from Mass-Peak Overlaps in Atom Probe Microscopy.

There are many sources of random and systematic error in composition quantification by atom probe microscopy, often, however, only statistical error is reported. Significantly larger errors can occur from the misidentification of ions and overlaps or interferences of peaks in the mass spectrum. These overlaps can be solved using maximum likelihood estimation (MLE), improving the accuracy of the result, but with an unknown effect on the precision. An analytical expression for the uncertainty of the MLE solution is presented and it is demonstrated to be much more accurate than the existing methods. In one example, the commonly used error estimate was five times too small.Literature results containing overlaps most likely underestimate composition uncertainty because of the complexity of correctly dealing with stochastic effects and error propagation. The uncertainty depends on the amount of overlapped intensity, for example being ten times worse for the CO/Fe overlap than the Cr/Fe overlap. Using the methods described here, accurate estimation of error, and the minimization of this could be achieved, providing a key milestone in quantitative atom probe. Accurate estimation of the composition uncertainty in the presence of overlaps is crucial for planning experiments and scientific interpretation of the measurements.