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Recent research works in the area of experimental and computational analyses of microscale mechanisms of strength, damage and degradation of glass fiber polymer composites for wind energy applications, which were carried out in the framework of a series of Sino–Danish collaborative research projects, are summarized in this article. In a series of scanning electron microscopy in situ experimental studies of composite degradation under off-axis tensile, compressive and cyclic loadings as well as three-dimensional computational experiments based on micromechanics of composites and damage mechanics, typical damage mechanisms of wind turbine blade composites were clarified. It was demonstrated that the damage mechanisms in the composites strongly depend on the orientation angle of the applied loading with the fiber direction. The matrix cracking was observed to be the main damage mechanism for tensile axial (or slightly off-axis axial) loading; for all other cases (off-axis tensile, compressive and cyclic tensile loadings), the interface debonding and shear control the damage mechanisms. [ABSTRACT FROM AUTHOR] more...

Rationale: There are unexplained geographical and seasonal differences in the short-term effects of fine particulate matter (PM(2.5)) on human health. The hypothesis has been advanced to include the possibility that such differences might be due to variations in the PM(2.5) chemical composition, but evidence supporting this hypothesis is lacking.Objectives: To examine whether variation in the relative risks (RR) of hospitalization associated with ambient exposure to PM(2.5) total mass reflects differences in PM(2.5) chemical composition.Methods: We linked two national datasets by county and by season: (1) long-term average concentrations of PM(2.5) chemical components for 2000-2005 and (2) RRs of cardiovascular and respiratory hospitalizations for persons 65 years or older associated with a 10-microg/m(3) increase in PM(2.5) total mass on the same day for 106 U.S. counties for 1999 through 2005.Measurements and Main Results: We found a positive and statistically significant association between county-specific estimates of the short-term effects of PM(2.5) on cardiovascular and respiratory hospitalizations and county-specific levels of vanadium, elemental carbon, or nickel PM(2.5) content.Conclusions: Communities with higher PM(2.5) content of nickel, vanadium, and elemental carbon and/or their related sources were found to have higher risk of hospitalizations associated with short-term exposure to PM(2.5). [ABSTRACT FROM AUTHOR] more...

Time series models relating short-term changes in air pollution levels to daily mortality counts typically assume that the effects of air pollution on the log relative rate of mortality do not vary with time. However, these short-term effects might plausibly vary by season. Changes in the sources of air pollution and meteorology can result in changes in characteristics of the air pollution mixture across seasons. The authors developed Bayesian semiparametric hierarchical models for estimating time-varying effects of pollution on mortality in multisite time series studies. The methods were applied to the database of the National Morbidity and Mortality Air Pollution Study, which includes data for 100 US cities, for the period 1987-2000. At the national level, a 10-microg/m(3) increase in particulate matter less than 10 microm in aerodynamic diameter at a 1-day lag was associated with 0.15% (95% posterior interval (PI): -0.08, 0.39), 0.14% (95% PI: -0.14, 0.42), 0.36% (95% PI: 0.11, 0.61), and 0.14% (95% PI: -0.06, 0.34) increases in mortality for winter, spring, summer, and fall, respectively. An analysis by geographic region found a strong seasonal pattern in the Northeast (with a peak in summer) and little seasonal variation in the southern regions of the country. These results provide useful information for understanding particle toxicity and guiding future analyses of particle constituent data. [ABSTRACT FROM AUTHOR] more...

BACKGROUND: Lack of knowledge regarding particulate matter (PM) characteristics associated with toxicity is a crucial research gap. Short-term effects of PM can vary by location, possibly reflecting regional differences in mixtures. A report by Lippmann et al. [Lippmann et al., Environ Health Perspect 114:1662-1669 (2006)] analyzed mortality effect estimates from the National Morbidity, Mortality, and Air Pollution Study (NMMAPS) for 1987-1994. They found that average concentrations of nickel or vanadium in PM2.5 (PM with aerodynamic diameter < 2.5 microm) positively modified the lag-1 day association between PM10 and all-cause mortality. OBJECTIVE: We reestimated the relationship between county-specific lag-1 PM10 (PM with aerodynamic diameter < 10 microm) effects on mortality and county-specific nickel or vanadium PM2.5 average concentrations using 1987-2000 effect estimates. We explored whether such modification is sensitive to outliers. METHODS: We estimated long-term average county-level nickel and vanadium PM2.5 concentrations for 2000-2005 for 72 U.S. counties representing 69 communities. We fitted Bayesian hierarchical regression models to investigate whether county-specific short-term effects of PM10 on mortality are modified by long-term county-specific nickel or vanadium PM2.5 concentrations. We conducted sensitivity analyses by excluding individual communities and considering log-transformed data. RESULTS: Our results were consistent with those of Lippmann et al. However, we found that when counties included in the NMMAPS New York community were excluded from the sensitivity analysis, the evidence of effect modification of nickel or vanadium on the short-term effects of PM10 mortality was much weaker and no longer statistically significant. CONCLUSIONS: Our analysis does not contradict the hypothesis that nickel or vanadium may increase the risk of PM to human health, but it highlights the sensitivity of findings to particularly influential observations. [ABSTRACT FROM AUTHOR] more...

When studying the impact of policy interventions or natural experiments on air pollution, such as new environmental policies or the opening or closing of an industrial facility, careful statistical analysis is needed to separate causal changes from other confounding factors. Using COVID-19 lockdowns as a case study, we present a comprehensive framework for estimating and validating causal changes from such perturbations. We propose using flexible machine learning-based comparative interrupted time series (CITS) models for estimating such a causal effect. We outline the assumptions required to identify causal effects, showing that many common methods rely on strong assumptions that are relaxed by machine learning models. For empirical validation, we also propose a simple diagnostic criterion, guarding against false effects in baseline years when there was no intervention. The framework is applied to study the impact of COVID-19 lockdowns on atmospheric nitrogen dioxide (NO2) levels in the eastern United States. The machine learning approaches guard against false effects better than common methods and suggest decreases in NO2 levels in 4 US cities (Boston, Massachusetts; New York, New York; Baltimore, Maryland; and Washington, DC) during the pandemic lockdowns. The study showcases the importance of our validation framework in selecting a suitable method and the utility of a machine learning-based CITS model for studying causal changes in air pollution time series. This article is part of a Special Collection on Environmental Epidemiology., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.) more...

Background: It was previously found that moving to lower-poverty/higher-opportunity neighborhoods as part of a housing mobility program was associated with improvements in asthma exacerbations and symptoms among children with asthma. Whether some subsets of children with asthma experience a greater improvement in asthma morbidity after moving is unknown., Objective: Our aim was to determine whether the benefits of moving to lower-poverty/higher-opportunity neighborhoods were concentrated in subsets of participants with asthma., Methods: We conducted a secondary analysis of the participants in the Mobility Asthma Project. Generalized estimating equations were used to assess the association between moving and asthma exacerbations and maximum symptom days. Separately, these models were then stratified by sex, age, body mass index, allergic sensitization, asthma severity, and stress before the move to estimate stratum-specific odds ratios for moving., Results: Participants broadly experienced a postmove reduction in odds of an exacerbation and maximum symptom days. Male children and children at a higher asthma controller medication treatment step experienced a greater reduction in maximum symptom days with moving., Conclusion: Children with asthma experience a reduction in odds of an exacerbation and symptoms after moving to lower-poverty/higher-opportunity neighborhoods. These improvements in asthma outcomes are seen regardless of baseline sex, age, body mass index, allergic sensitization, asthma severity, and premove stress., Competing Interests: Supported by the 10.13039/100000066National Institute of Environmental Health Sciences (grant R01ES026170) and the 10.13039/100000060National Institute of Allergy and Infectious Diseases (grants K24AI114769 [to E.C.M.] and K23AI159144 [to T.L.G.]). Disclosure of potential conflict of interest: The authors declare that they have no relevant conflicts of interest., (© 2025 Published by Elsevier Inc. on behalf of the American Academy of Allergy, Asthma & Immunology.) more...

A growing literature within the field of air pollution exposure assessment addresses the issue of environmental justice. Leveraging the increasing availability of exposure datasets with broad spatial coverage and high spatial resolution, a number of works have assessed inequalities in exposure across racial/ethnic and other socioeconomic groupings. However, environmental justice research presents the additional need to evaluate exposure inequity-inequality that is systematic, unfair, and avoidable-which may be framed in several ways. We discuss these framings and describe inequality and inequity conclusions provided from several contrasting approaches drawn from recent work. We recommend that future work addressing environmental justice interventions include complementary "Exposure-driven" and "Socially weighted" metrics, taking an intersectional view of areas and social groups that are both disproportionately impacted by pollution and are impacted by additional health risks resulting from structural racism and consider implications for environmental justice beyond distributional equity. more...

Background: Pesticides may impact respiratory health, yet evidence of their impact on pediatric asthma morbidity is limited, particularly among urban children., Objective: To characterize pesticide biomarker concentrations and evaluate their associations with pediatric asthma morbidity among predominantly low-income, Black children in Baltimore City, USA., Methods: We measured urinary concentrations of 10 biomarkers for pyrethroid insecticides (cyfluthrin:4F-3PBA, permethrin:3PBA), organophosphate insecticides (chlorpyrifos:TCPY, malathion:MDA, parathion:PNP, diazinon:IMPY), and herbicides (glyphosate:AMPA, GPS; 2,4-dicholorphenoxyacetic acid:2,4-D; 2,4,5-tricholorphenoxyacetic acid:2,4,5-T) among 148 children (5-17 years) with established asthma. Urine samples and asthma morbidity measures (asthma symptoms, healthcare utilization, lung function and inflammation) were collected every three months for a year. Generalized estimating equations were used to examine associations between pesticide biomarker concentrations and asthma morbidity measures, controlling for age, sex, race, caregiver education, season, and environmental tobacco smoke. In sensitivity analyses, we assessed the robustness of our results after accounting for environmental co-exposures., Results: Frequently detected (≥90% detection) pesticide biomarker concentrations (IMPY, 3PBA, PNP, TCPY, AMPA, GPS) varied considerably within children over the follow-up period (intraclass correlation coefficients: 0.1-0.2). Consistent positive significant associations were observed between the chlorpyrifos biomarker, TCPY, and asthma symptoms. Urinary concentrations of TCPY were associated with increased odds of coughing, wheezing, or chest tightness (adjusted Odds Ratio, aOR, TCPY:1.60, 95% Confidence Interval, CI:1.17-2.18). Urinary concentrations of TCPY were also associated with maximal symptom days (aOR:1.38, CI:1.02-1.86), exercise-related symptoms (aOR:1.63, CI:1.09-2.44), and hospitalizations for asthma (aOR:2.84, CI:1.08-7.43). We did not observe consistent evidence of associations between the pesticide exposures assessed and lung function or inflammation measures., Conclusion: Among predominantly Black children with asthma, we found evidence that chlorpyrifos is associated with asthma morbidity. Further research is needed to assess the contribution of pesticide exposures to pediatric respiratory health and characterize exposure sources among vulnerable populations to inform targeted interventions against potentially harmful pesticide exposures., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.) more...

The objective of this study is to illustrate the advantages of robot-assisted unilateral biportal endoscopy in lumbar decompression fusion and internal fixation surgery. According to the different surgical methods, we divided the 26 patients into 2 groups, robot-assisted unilateral biportal endoscopy for lumbar interbody fusion (R-ULIF) group and percutaneous endoscopic lumbar decompression and interbody fusion (Endo-LIF) group, with a 1:1 ratio. Gender, disease course, lesion site, fluoroscopy times, operative time, blood loss, postoperative hospital stay, screw placement success rate, fusion rate, complications rate, postoperative pain visual analog scale (VAS) (The VAS score is used only to evaluate pain in the lower back and legs.) Oswestry Disability Index (ODI) (The ODI score can serve as a reference indicator for evaluating the effectiveness of treatment for patients with low back pain, and has good responsiveness in assessing patients with chronic low back pain), and MacNab (The MacNab standard is divided into 4 levels: excellent, good, fair, and poor, which can be used to evaluate the therapeutic efficacy of certain spinal surgeries) standard efficacy evaluation were analyzed and compared between the 2 groups. All patients successfully completed the surgery. Compared with the Endo-LIF group, the R-ULIF group had fewer fluoroscopy procedures, less intraoperative blood loss, and shorter postoperative hospital stay (P < .05). The VAS scores and ODI scores of both groups significantly decreased at all-time points (P < .05). The ODI scores of the R-ULIF group were better than the Endo-LIF group at 1 month and 3 months after surgery (P = .017/P = .047), but there was no statistically significant difference between the groups before surgery and 1 week after surgery (P > .05). The efficacy was evaluated using the MacNab criteria at 6 months after surgery. The R-ULIF group has an excellent and good rate of 84.6%, while the Endo-LIF group has an excellent and good rate of 76.9% (P = 1.000). Robot-assisted unilateral biportal endoscopy for lumbar interbody and fusion surgery has shown short-term clinical efficacy in the treatment of lumbar disc herniation combined with lumbar instability, surpassing endoscopic lumbar interbody fusion surgery. Robot-assisted unilateral biportal endoscopy for lumbar interbody and fusion surgery has demonstrated high success rate in screw placement, minimal radiation exposure, less intraoperative blood loss, shorter hospital stay, and thus deserves further clinical promotion., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.) more...

Background: This reported procedure combines the orthopedic surgical robot with the unilateral biportal endoscopy-lumbar interbody fusion (UBE-LIF), utilizing the UBE's wide viewing field and operating space to perform minimally invasive decompressive fusion of the lesioned segment, and the orthopedic surgical robot's intelligence and precision to perform percutaneous pedicle screw placement. The advancement of this procedure lies in the superposition of advantages and offsetting disadvantages of the two new technologies, and the maximum effect of treatment is achieved with maximum minimization of invasiveness and precision under the monitoring of imaging instruments to maximize the benefit of patients, and this review reports a case of multiple-segment lumbar decompression and fusion surgery for lumbar disc herniation via robot-assisted UBE for reference., Case Summary: A 44-year-old patient presented to our hospital. Combining various clinical data, we diagnosed the patient with lumbar disc herniation with radiculopathy, lumbar spondylolisthesis, and lumbar spinal stenosis. We developed a surgical plan of "UBE decompression + UBE-LIF + orthopedic surgery robot-assisted percutaneous pedicle screw implantation for internal fixation". The results were satisfactory., Conclusion: We present an extremely rare case of multiple-segment lumbar decompression and fusion surgery for lumbar disc herniation via robot-assisted UBE and achieved good results. Therefore, the technique is worthy of clinical promotion., Competing Interests: Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article., (©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.) more...

Importance: Structural racism has been implicated in the disproportionally high asthma morbidity experienced by children living in disadvantaged, urban neighborhoods. Current approaches designed to reduce asthma triggers have modest impact., Objective: To examine whether participation in a housing mobility program that provided housing vouchers and assistance moving to low-poverty neighborhoods was associated with reduced asthma morbidity among children and to explore potential mediating factors., Design, Setting, and Participants: Cohort study of 123 children aged 5 to 17 years with persistent asthma whose families participated in the Baltimore Regional Housing Partnership housing mobility program from 2016 to 2020. Children were matched to 115 children enrolled in the Urban Environment and Childhood Asthma (URECA) birth cohort using propensity scores., Exposure: Moving to a low-poverty neighborhood., Main Outcomes: Caregiver-reported asthma exacerbations and symptoms., Results: Among 123 children enrolled in the program, median age was 8.4 years, 58 (47.2%) were female, and 120 (97.6%) were Black. Prior to moving, 89 of 110 children (81%) lived in a high-poverty census tract (>20% of families below the poverty line); after moving, only 1 of 106 children with after-move data (0.9%) lived in a high-poverty tract. Among this cohort, 15.1% (SD, 35.8) had at least 1 exacerbation per 3-month period prior to moving vs 8.5% (SD, 28.0) after moving, an adjusted difference of -6.8 percentage points (95% CI, -11.9% to -1.7%; P = .009). Maximum symptom days in the past 2 weeks were 5.1 (SD, 5.0) before moving and 2.7 (SD, 3.8) after moving, an adjusted difference of -2.37 days (95% CI, -3.14 to -1.59; P < .001). Results remained significant in propensity score-matched analyses with URECA data. Measures of stress, including social cohesion, neighborhood safety, and urban stress, all improved with moving and were estimated to mediate between 29% and 35% of the association between moving and asthma exacerbations., Conclusions and Relevance: Children with asthma whose families participated in a program that helped them move into low-poverty neighborhoods experienced significant improvements in asthma symptom days and exacerbations. This study adds to the limited evidence suggesting that programs to counter housing discrimination can reduce childhood asthma morbidity. more...

Rationale: Indoor air pollution represents a modifiable risk factor for respiratory morbidity in chronic obstructive pulmonary disease (COPD). The effects of indoor air pollution, as well as the impact of interventions to improve indoor air quality, on cardiovascular morbidity in COPD remain unknown. Objectives: To determine the association between indoor particulate matter (PM) and heart rate variability (HRV), a measure of cardiac autonomic function tied to cardiovascular morbidity and mortality, as well as the impact of household air purifiers on HRV. Methods: Former smokers with moderate-severe COPD were recruited from a 6-month randomized controlled trial of a portable air cleaner intervention to undergo paired assessment of both in-home PM and HRV using 24-hour Holter monitoring at up to five time points. Primary outcomes were HRV measures tied to cardiovascular morbidity (standard deviation of normal-to-normal intervals [SDNN] and root mean square of successive differences between normal-to-normal intervals [RMSSD]). Measurements and Results: Eighty-five participants contributed 317 HRV measurements. A twofold increase in household PM ⩽2.5 µm in aerodynamic diameter was associated with decreases in SDNN (β, -2.98% [95% confidence interval (CI), -5.12 to -0.78]) and RMSSD (β, -4.57% [95% CI, -10.1 to -1.60]). The greatest effects were observed with ultrafine particles (<100 nm) (RMSSD; β, -16.4% [95% CI, -22.3 to -10.1]) and among obese participants. Participants randomized to the active air cleaner saw improvements in RMSSD (β, 25.2% [95% CI, 2.99 to 52.1]), but not SDNN (β, 2.65% [95% CI, -10.8 to 18.1]), compared with the placebo group. Conclusions: This is the first U.S. study to describe the association between household PM and cardiac autonomic function among individuals with COPD, as well as the potential cardiovascular health benefits of household air cleaners. more...

Objective: To determine if the addition of home environmental control strategies (ECSs) to controller medication titration reduces asthma controller medication requirements and in-home allergen concentrations among children with persistent asthma in Baltimore City., Methods: 155 children ages 5-17 with allergen-sensitized asthma were enrolled in a 6-month randomized clinical trial of multifaceted, individually-tailored ECS plus asthma controller medication titration compared to controller medication titration alone. Participants had to meet criteria for persistent asthma and have had an exacerbation in the previous 18 months. Allergen sensitization (mouse, cockroach, cat, dog, dust mite) was assessed at baseline and home dust allergen concentrations were measured at baseline, 3 and 6 months. ECS was delivered 3-4 times over the trial. Asthma controller medication was titrated using a guidelines-based algorithm at baseline, 2, 4, and 6 months. The primary outcome was controller medication treatment step at 6 months (0-6, as-needed albuterol to high-dose ICS + LABA)., Results: The population was predominately Black (90%), on public insurance (93%), and male (61%). The mean age was 10.1 years (SD 3.3). More than 70% were sensitized to a rodent, >50% to cockroach, and 70% were polysensitized. At 6 months, there were no differences in either treatment step (3.8 [SD 1.4] vs. 3.7 [SD 1.5]) or allergen concentrations between groups., Conclusion: Among this predominantly low-income, Black pediatric asthma population, the addition of ECS to controller medication titration reduced neither indoor allergen concentrations nor controller medication requirements compared to controller medication titration alone. more...

Background: Post-traumatic cauda equina nerve calcification is extremely rare in clinical practice, and its etiology, pathogenesis, treatment and prognosis are unclear. There are few studies and reports on Post-traumatic cauda equina nerve calcification, and this review reports a case of Post-traumatic cauda equina nerve calcification for reference., Case Summary: A 52-year-old patient presented to our hospital with a history of lumbar spinal stenosis and a lumbar vertebral fracture caused by trauma. The patient's right lower limb had weakness in hip flexion, knee extension and plantarflexion with muscle strength grade 3, right ankle dorsiflexion and thumb dorsiflexion with muscle strength grade 0. The patient's skin sensation below the right knee plane disappeared. The patient's Computed tomography (CT) data showed signs of cauda equina nerve calcification and the terminal filaments in the plane of the third to fifth lumbar vertebrae. After treatment the patient's symptoms were slightly relieved., Conclusion: We provide an extremely rare case of Post-traumatic cauda equina nerve calcification and offer a conservative treatment plan. However, the etiology, mechanism and treatment of Post-traumatic cauda equina nerve calcification are still unclear. This requires scholars to conduct more research and exploration in this area., Competing Interests: Conflict-of-interest statement: All authors declare that they have no conflict of interest to disclose., (©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.) more...

Background: Phthalates are synthetic chemicals present in building materials, personal care products and other consumer goods. Limited studies link phthalates to pediatric asthma incidence; however, their effects on respiratory-related outcomes among those with pre-existing asthma remains unclear., Objective: We examined associations between phthalates and asthma symptoms, healthcare use, lung function, and lung inflammation among children with asthma., Methods: We collected repeated measures of urinary biomarkers for select phthalates and phthalate replacements (MBzP, MCINP, MCIOP, MCPP, MECPTP, MEHHTP, molar sum of DEHP biomarkers [MECPP, MEHHP, MEHP, MEOHP], MEP, MiBP, MnBP) and asthma symptoms, healthcare utilization, lung function, and inflammation among 148 predominantly low-income Black children (5-17 years) with persistent asthma every 3 months for one year. We used generalized estimating equations to assess associations between biomarker concentrations and asthma-related measures adjusting for age, sex, race/ethnicity, caregiver's education level, presence of smokers in the home, and season. We also considered co-exposures to other contaminants previously associated with asthma morbidity., Results: We observed consistent positive associations with individual DEHP biomarkers, the molar sum of DEHP, and BBzP with increased odds of asthma symptoms and with healthcare utilization (adjusted Odds Ratio for general asthma symptoms: ΣDEHP:1.49,95% Confidence Interval, CI:1.08-2.07; BBzP:1.34, CI:1.04-1.73). We observed similar associations between the DEHP phthalate replacement biomarker MEHHTP and most asthma symptoms evaluated; and with select low molecular weight phthalates (DiBP, DBP) and healthcare utilization. Results were similar when controlling for other environmental exposures (e.g., PM 2.5 , BPA). No associations were observed with lung function or inflammation, and overall, we did not observe consistent evidence of sexually dimorphic effects., Conclusion: In the present study, we found evidence to suggest that exposure to select phthalates may be associated with asthma symptoms and healthcare utilization. These findings warrant confirmation given the high asthma burden and widespread and disparate phthalate exposures reported among select populations of color., (Copyright © 2022 Elsevier Inc. All rights reserved.) more...

It has been suggested that pets play a critical role in the maintenance of methicillin-resistant (MR) and multidrug-resistant (MDR) Staphylococcus spp. in the household. We examined risk factors for carriage of antimicrobial-resistant coagulase-positive staphylococci, with particular attention to Staphylococcus aureus and Staphylococcus pseudintermedius isolated from pets living in households of people diagnosed with methicillin-resistant S. aureus (MRSA) skin or soft-tissue infection. We analyzed data collected cross-sectionally from a study conducted in 2012 that evaluated the transmission of MRSA and other staphylococci from humans, their pets and the environment (Pets and Environmental Transmission of Staphylococci [PETS] study). We used unadjusted and adjusted stratified logistic regression analyses with household-clustered standard errors to evaluate the association between demographic, healthcare-related, contact-related and environmental risk factors and MDR Staphylococcus spp. isolated from dogs and cats. Staphylococcal isolates obtained from dogs (n = 63) and cats (n = 47) were included in these analyses. The use of oral or injectable antimicrobials by the pets during the prior year was the main risk factor of interest. Based on our results, 50% (12/24) of S. aureus, 3.3% (1/30) of S. pseudintermedius and 25% (14/56) of other coagulase-positive staphylococci (CPS) were determined to be MDR. S. aureus isolates were more likely to be MDR compared with S. pseudintermedius. We did not find a significant statistical association between the use of oral or injectable antimicrobials in the prior year and the presence of MDR bacteria. The results suggest that drivers of antimicrobial resistance in household staphylococci may vary by bacterial species, which could have implications for one health intervention strategies for staphylococci and inform the investigation of other reverse zoonoses, such as COVID-19., (© 2022 The Authors. Zoonoses and Public Health published by Wiley-VCH GmbH.) more...

Background: Neighborhood poverty has been associated with poor health outcomes. Previous studies have also identified adverse respiratory effects of long-term ambient ozone. Factors associated with neighborhood poverty may accentuate the adverse impact of ozone on respiratory health., Objectives: To evaluate whether neighborhood poverty modifies the association between ambient ozone exposure and respiratory morbidity including symptoms, exacerbation risk, and radiologic parameters, among participants of the SPIROMICS AIR cohort study., Methods: Spatiotemporal models incorporating cohort-specific monitoring estimated 10-year average outdoor ozone concentrations at participants' homes. Adjusted regression models were used to determine the association of ozone exposure with respiratory outcomes, accounting for demographic factors, education, individual income, body mass index (BMI), and study site. Neighborhood poverty rate was defined by percentage of families living below federal poverty level per census tract. Interaction terms for neighborhood poverty rate with ozone were included in covariate-adjusted models to evaluate for effect modification., Results: 1874 participants were included in the analysis, with mean (± SD) age 64 (± 8.8) years and FEV 1 (forced expiratory volume in one second) 74.7% (±25.8) predicted. Participants resided in neighborhoods with mean poverty rate of 9.9% (±10.3) of families below the federal poverty level and mean 10-year ambient ozone concentration of 24.7 (±5.2) ppb. There was an interaction between neighborhood poverty rate and ozone concentration for numerous respiratory outcomes, including COPD Assessment Test score, modified Medical Research Council Dyspnea Scale, six-minute walk test, and odds of COPD exacerbation in the year prior to enrollment, such that adverse effects of ozone were greater among participants in higher poverty neighborhoods., Conclusion: Individuals with COPD in high poverty neighborhoods have higher susceptibility to adverse respiratory effects of ambient ozone exposure, after adjusting for individual factors. These findings highlight the interaction between exposures associated with poverty and their effect on respiratory health., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Daniel Belz reports grant support from NIH/NHLBI. Mark Dransfield reports grant support from NIH, DOD, and the American Lung Association; consulting from AstraZeneca, GlaxoSmithKline, Pulmonx, Teva; and contracted clinical trials through Boerhinger Ingelheim, Gala, and Pulmonx. MeiLan Han reports consulting for Novartis, Sunovion, Cipla, Chiesi, Teva, Verona, Merck, Mylan, Sanofi, GlaxoSmithKline, Boehringer Ingelheim and AstraZeneca as well as research support from Novartis and Sunovion. Jerry Krishnan reports research grants from NIH, PCORI, and Sergey Brin Family Foundation as well as consulting fees from GlaxoSmithKline for monoclonal antibody against SARS-CoV-2. Nadia Hansel reports grants from NIH, grants from COPD Foundation, grants and personal fees from AstraZeneca, grants and personal fees from GSK, grants from Boehringer Ingelheim, personal fees from Mylan during the conduct of the study., (Copyright © 2022 Elsevier B.V. All rights reserved.) more...

The control of ambient air quality in the United States has been a major public health success since the passing of the Clean Air Act, with particulate matter (PM) reductions resulting in an estimated 160 000 premature deaths prevented in 2010 alone. Currently, public policy is oriented around lowering the levels of individual pollutants and this focus has driven the nature of much epidemiological research. Recently, attention has been given to viewing air pollution as a complex mixture and to developing a multi-pollutant approach to controlling ambient concentrations. We present a statistical approach for estimating the health impacts of complex environmental mixtures using a mixture-altering contrast, which is any comparison, intervention, policy, or natural experiment that changes a mixture's composition. We combine the notion of mixture-altering contrasts with sliced inverse regression, propensity score matching, and principal stratification to assess the health effects of different air pollution chemical mixtures. We demonstrate the application of this approach in an analysis of the health effects of wildfire PM air pollution in the Western US., (© 2022 The Authors. Statistics in Medicine published by John Wiley & Sons Ltd.) more...

While associations between short-term exposure to fine particulate matter (PM 2.5 ) and risk of hospitalization are well documented and evidence suggests that such associations change over time, it is unclear whether these temporal changes exist in understudied less-urban areas or differ by sub-population. We analyzed daily time-series data of 968 continental U.S. counties for 2000-2016, with cause-specific hospitalization from Medicare claims and population-weighted PM 2.5 concentrations originally estimated at 1km × 1 km from a hybrid model. Circulatory and respiratory hospitalizations were categorized based on primary diagnosis codes at discharge. Using modified Bayesian hierarchical modelling, we evaluated the temporal trend in association between PM 2.5 and hospitalizations and whether disparities in this trend exist across individual-level characteristics (e.g., sex, age, race, and Medicaid eligibility as a proxy for socio-economic status) and urbanicity. Urbanicity was categorized into three levels by county-specific percentage of urban population based on urban rural delineation from the U.S. Census. In this cohort with understudied less-urban areas without regulatory monitors, we still found positive association between circulatory and respiratory hospitalization and short-term exposure to PM 2.5 , with higher effect estimates towards the end of study period. Consistent with current literature, we identified significant disparity in associations by race, socioeconomic status and urbanicity. We found that the percentage change in circulatory hospitalization rate per 10 μg/m 3 increase in PM 2.5 was higher in the 2008-2016 time period compared to the 2000-2007 period by 0.33% (95% posterior credible interval 0.22, 0.44%), 0.52% (0.33, 0.69%), and 0.67% (0.53, 0.83%) for low, medium and high tertiles of urban areas, respectively. We also observed significant differences in temporal trends of associations across socioeconomic status, sex, and age, indicating a possible widening in disparity of PM 2.5 -related health burden. This study raises the importance of considering environmental justice issues in PM 2.5 -related health impacts with respect to how associations may change over time., (Copyright © 2021 Elsevier Inc. All rights reserved.) more...

Background: Neighborhood and caregiver characteristics have each been linked to children's asthma outcomes, but less is known about how caregiver psychosocial functioning may explain the link between neighborhood characteristics and asthma outcomes., Objective: To examine associations between neighborhood safety, caregiver stress and depressive symptoms, and children's asthma outcomes, and to evaluate whether caregiver stress and depressive symptoms mediate the relationship between neighborhood safety and asthma outcomes., Methods: We analyzed baseline data from a prospective cohort study of the effects of a housing mobility program on children's asthma-related outcomes. Age- and sex-adjusted models evaluated associations of neighborhood safety, and caregiver stress and depressive symptoms, with children's asthma symptoms and exacerbations., Results: Participants were 140 low-income children with persistent asthma (98% Black participants; 53% males; mean age, 9.0 years) with an average of 7.1 ± 5.3 maximum symptom days per 2 weeks. Lower neighborhood safety, and higher caregiver stress and depressive symptoms, were associated with higher asthma symptoms, but not exacerbations, in adjusted models (eg, for neighborhood safety, maximum symptom days: odds ratio, 1.41; 95% CI, 1.07-1.88; for caregiver stress, maximum symptom days: odds ratio, 1.08; 95% CI, 1.01-1.15; for depressive symptoms, maximum symptom days: odds ratio, 1.05; 95% CI, 1.00-1.11). Exploratory analyses suggested that caregiver stress partially mediated associations between neighborhood safety and asthma symptoms for children in unsafe neighborhoods., Conclusions: Neighborhood safety was associated with children's asthma symptoms independent from caregiver stress and depressive symptoms, although for children in unsafe neighborhoods, caregiver stress may partially mediate this association. Findings suggest the importance of targeting multiple systems to improve children's asthma outcomes., (Copyright © 2021 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.) more...

Background: The era of big data has enabled sophisticated models to predict air pollution concentrations over space and time. Historically these models have been evaluated using overall metrics that measure how close predictions are to monitoring data. However, overall methods are not designed to distinguish error at timescales most relevant for epidemiologic studies, such as day-to-day errors that impact studies of short-term health associations., Methods: We introduce frequency band model performance, which quantifies health estimation capacity of air quality prediction models for time series studies of air pollution and health. Frequency band model performance uses a discrete Fourier transform to evaluate prediction models at timescales of interest. We simulated fine particulate matter (PM 2.5 ), with errors at timescales varying from acute to seasonal, and health time series data. To compare evaluation approaches, we use correlations and root mean squared error (RMSE). Additionally, we assess health estimation capacity through bias and RMSE in estimated health associations. We apply frequency band model performance to PM 2.5 predictions at 17 monitors in 8 US cities., Results: In simulations, frequency band model performance rates predictions better (lower RMSE, higher correlation) when there is no error at a particular timescale (e.g., acute) and worse when error is added to that timescale, compared to overall approaches. Further, frequency band model performance is more strongly associated (R 2  = 0.95) with health association bias compared to overall approaches (R 2  = 0.57). For PM 2.5 predictions in Salt Lake City, UT, frequency band model performance better identifies acute error that may impact estimated short-term health associations., Conclusions: For epidemiologic studies, frequency band model performance provides an improvement over existing approaches because it evaluates models at the timescale of interest and is more strongly associated with bias in estimated health associations. Evaluating prediction models at timescales relevant for health studies is critical to determining whether model error will impact estimated health associations., (© 2022. The Author(s).) more...

Background: Whether concomitant home exposures modify the effectiveness of mouse allergen reduction among mouse-sensitized children with asthma is unknown., Objective: To determine whether a lower baseline home mouse allergen level, lower particulate matter 10 μ or less (PM 10 ), and the absence of sensitization and exposure to other indoor allergens are associated with greater improvements in asthma associated with mouse allergen reduction., Methods: A secondary analysis of a randomized clinical trial of a home mouse allergen intervention was performed to examine the effect of 3 indoor factors on the relationship between mouse allergen reduction and a range of asthma outcomes., Results: Participants (N = 297) were predominantly minority (78% African American, 22% Hispanic) and publicly insured (88%). Higher baseline mouse allergen levels were associated with a greater response to mouse allergen reduction for several symptom and exacerbation outcomes. Lower indoor PM 10 levels were associated with a greater response to mouse allergen reduction for several symptom outcomes, but not exacerbation outcomes. Overall, sensitization and exposure to other indoor allergens did not appear to modify the effect of mouse allergen reduction., Conclusions: In this population of predominantly low-income children with persistent asthma and mouse sensitization, mouse allergen reduction was associated with improvements in asthma, especially among those with high baseline mouse allergen exposure. Lower indoor PM 10 was associated with greater improvements in asthma symptoms., (Copyright © 2021 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.) more...

Background: Short-term exposure to fine particulate matter (PM 2·5 ) is associated with increased risk of hospital admissions and mortality, and health risks differ by the chemical composition of PM 2·5 . Policies to control PM 2·5 could change its chemical composition and total mass concentration, leading to change in the subsequent health impact. However, there is little ence on whether associations between PM 2·5 and health exhibit temporal variation. We investigated whether risks of hospitalisations from short-term exposure to PM 2·5 varied over time in the USA., Methods: We did a time-series analysis using a national dataset comprising daily circulatory and respiratory hospitalisation rates of Medicare beneficiaries (age ≥65 years) and PM 2·5 in 173 US counties from 1999 to 2016. We fitted modified quasi-Poisson models to estimate temporal trends of associations within a county, and pooled county-level estimates using Bayesian hierarchical modelling to generate an overall estimate., Findings: The study included 10 559 654 circulatory and 3 027 281 respiratory hospitalisations. We identified changes in the national average association between previous-day PM 2·5 and respiratory hospitalisation over time, with a U-shape that is robust under stratification, linear, and non-linear models. The change in risk of respiratory hospitalisation per 10 μg/m 3 increase in previous-day PM 2·5 decreased from 0·75% (95% posterior credible interval 0·05 to 1·46) in 1999 to -0·28% (-0·79 to 0·23) in 2008, and then increased to 1·44% (0·00 to 2·91) in 2016. No statistically significant temporal change was observed for associations between same-day PM 2·5 and circulatory hospitalisation., Interpretation: Hospitalisation risk from PM 2·5 changes over time and has increased over the past 7 years in study, especially in northeastern USA. The temporal trend differs by cause of hospitalisation. This study emphasises the necessity of evaluating temporal heterogeneity in health impacts of PM 2·5 and suggests caution in applying association estimates to a different time period., Funding: US Environmental Protection Agency and Yale Institute for Biospheric Studies., Competing Interests: Declaration of interests We declare no competing interests., (Copyright © 2021 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 license. Published by Elsevier Ltd.. All rights reserved.) more...

Background: Phthalates are endocrine disrupting compounds linked to various adverse health effects. U.S. national biomonitoring data indicate that select minority subgroups may suffer disparate exposures to phthalates. Still, exposures and their respective determinants among these subgroups are not well characterized., Objective: We sought to examine determinants of phthalate exposure in a subsample of US-based Latino adults., Methods: We conducted a cross-sectional study on 94 Latino immigrant adults in Maryland. Participants were >18 years of age and working in a service-based industry. We administered an interviewer-administered questionnaire to capture information on potential exposure determinants (e.g., demographic characteristics, consumer product use, and workplace exposures and behaviors) and using HPLC/MS-MS we quantified concentrations of 9 urinary phthalate metabolites: monoethyl phthalate (MEP, diethyl phthalate metabolite); mono-n-butyl phthalate (MBP, di-n-butyl phthalate metabolite); mono-isobutyl phthalate (MiBP, di-isobutyl phthalate metabolite; monobenzyl phthalate (MBzP, benzylbutyl phthalate metabolite); molar sum of di-2-ethylhexyl phthalate or DEHP metabolites [mono-2-ethylhexyl phthalate (MEHP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), and mono-(2-ethyl-5-carboxypentyl) phthalate (MECCP)]; and mono(3-carboxypropyl) phthalate (MCPP, a non-specific metabolite of several phthalates including di-n-butyl phthalate and di-n-octyl phthalate). DEHP was analyzed as the molar sum of four metabolites (ΣDEHP = MEHP + MEHHP + MECPP + MEOHP). Spearman correlations, Wilcoxon-Mann-Whitney, and Kruskal-Wallis tests were conducted to assess bivariate associations between metabolite concentrations and potential exposure determinants. Covariates associated with metabolites at p < 0.10 in bivariate analyses were included in multivariable linear regression models to assess the independent effects of predictors on metabolite concentrations., Results: Uncorrected median phthalate metabolite concentrations were lower in our study population (50% of samples ranged between 1.4 and 23.6 μg/L. While we observed some significant associations with select predictors in our bivariate analysis, select associations were attenuated in multivariable regression models. In our final multivariable linear regression models, we found that use of bleach (β = 1.15, 95%CI:0.30, 2.00) and consumption pasta/rice/noodles (β = 0.87, 95%CI: 0.27, 1.46) was positively associated with MBzP concentrations. MEP concentrations were inversely associated with use of furniture polish (β = -1.17, 95%CI: 2.21, -0.12) and use of scented dryer sheets (β = -1.08, 95%CI: 2.01, -0.14). Lastly, ΣDEHP concentrations were inversely associated with use of degreaser (ß DEHP  = -0.65, 95%CI: 1.25, -0.05)., Conclusions: In this predominantly U.S.-based Central American subsample of adults, we observed lower metabolite concentrations than those previously reported in other U.S. studies and other countries. Our findings could be due, in part, to temporal trends in phthalate exposures and cultural differences related to exposure-related behaviors. While some exposure determinants were identified in our bivariate analyses, results from multivariable regression models did not provide clear results as many associations were attenuated. Environmental exposures may vary within minority subgroups and should be explored further in future studies to further inform exposure mitigation strategies., (Copyright © 2021 Elsevier GmbH. All rights reserved.) more...

Background: Although injuries experienced during hurricanes and other tropical cyclones have been relatively well-characterized through traditional surveillance, less is known about tropical cyclones' impacts on noninjury morbidity, which can be triggered through pathways that include psychosocial stress or interruption in medical treatment., Methods: We investigated daily emergency Medicare hospitalizations (1999-2010) in 180 US counties, drawing on an existing cohort of high-population counties. We classified counties as exposed to tropical cyclones when storm-associated peak sustained winds were ≥21 m/s at the county center; secondary analyses considered other wind thresholds and hazards. We matched storm-exposed days to unexposed days by county and seasonality. We estimated change in tropical cyclone-associated hospitalizations over a storm period from 2 days before to 7 days after the storm's closest approach, compared to unexposed days, using generalized linear mixed-effect models., Results: For 1999-2010, 175 study counties had at least one tropical cyclone exposure. Cardiovascular hospitalizations decreased on the storm day, then increased following the storm, while respiratory hospitalizations were elevated throughout the storm period. Over the 10-day storm period, cardiovascular hospitalizations increased 3% (95% confidence interval = 2%, 5%) and respiratory hospitalizations increased 16% (95% confidence interval = 13%, 20%) compared to matched unexposed periods. Relative risks varied across tropical cyclone exposures, with strongest association for the most restrictive wind-based exposure metric., Conclusions: In this study, tropical cyclone exposures were associated with a short-term increase in cardiorespiratory hospitalization risk among the elderly, based on a multi-year/multi-site investigation of US Medicare beneficiaries ≥65 years., Competing Interests: The authors report no conflicts of interest., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.) more...

Advances in computing technology have spurred two extraordinary phenomena in science: large-scale and high-throughput data collection coupled with the creation and implementation of complex statistical algorithms for data analysis. These two phenomena have brought about tremendous advances in scientific discovery but have raised two serious concerns. The complexity of modern data analyses raises questions about the reproducibility of the analyses, meaning the ability of independent analysts to recreate the results claimed by the original authors using the original data and analysis techniques. Reproducibility is typically thwarted by a lack of availability of the original data and computer code. A more general concern is the replicability of scientific findings, which concerns the frequency with which scientific claims are confirmed by completely independent investigations. Although reproducibility and replicability are related, they focus on different aspects of scientific progress. In this review, we discuss the origins of reproducible research, characterize the current status of reproducibility in public health research, and connect reproducibility to current concerns about the replicability of scientific findings. Finally, we describe a path forward for improving both the reproducibility and replicability of public health research in the future. more...

Heat exposure of a population is often estimated by applying temperatures from outdoor monitoring stations. However, this can lead to exposure misclassification if residents do not live close to the monitoring station and temperature varies over small spatial scales due to land use/built environment variability, or if residents generally spend more time indoors than outdoors. Here, we compare summertime temperatures measured inside 145 homes in low-income households in Baltimore city with temperatures from the National Weather Service weather station in Baltimore. There is a large variation in indoor temperatures, with daily-mean indoor temperatures varying from 10 °C lower to 10 °C higher than outdoor temperatures. Furthermore, there is only a weak association between the indoor and outdoor temperatures across all houses, indicating that the outdoor temperature is not a good predictor of the indoor temperature for the residences sampled. It is shown that much of the variation is due to differences in the availability of air conditioning (AC). Houses with central AC are generally cooler than outdoors (median difference of - 3.4 °C) while those with no AC are generally warmer (median difference of 1.4 °C). For the collection of houses with central or room AC, there is essentially no relationship between indoor and outdoor temperatures, but for the subset of houses with no AC, there is a weak relationship (correlation coefficient of 0.36). The results presented here suggest future epidemiological studies of indoor exposure to heat would benefit from information on the availability of AC within the population. more...

Background: Bisphenol A (BPA) has been linked with pediatric asthma development and allergic airway inflammation in animal models. Whether exposure to BPA or its structural analogs bisphenol S (BPS) and bisphenol F (BPF) is associated with asthma morbidity remains unknown., Objective: We examined associations between bisphenols and morbidity due to pediatric asthma., Methods: We quantified concentrations of BPA, BPS, and BPF in 660 urine samples from 148 predominantly low-income, African American children (aged 5-17 years) with established asthma. We used biobanked biospecimens and data on symptoms, health care utilization, and pulmonary function and inflammation that were collected every 3 months over the course of a year. We used generalized estimating equations to examine associations between concentrations or detection of urinary bisphenols and morbidity outcomes and assessed heterogeneity of associations by sex., Results: We observed consistent positive associations between BPA exposure and measures of asthma morbidity. For example, we observed increased odds of general symptom days (adjusted odds ratio [aOR] = 1.40 [95% C = 1.02-1.92]), maximal symptom days (aOR = 1.36 [95% CI = 1.00-1.83]), and emergency department visits (aOR = 2.12 [95% CI =1.28-3.51]) per 10-fold increase in BPA concentration. We also observed evidence of sexually dimorphic effects; BPA concentrations were associated with increased odds of symptom days and health care utilization only among boys. Findings regarding BPS and BPF did not consistently point to associations with asthma symptoms or health care utilization., Conclusion: We found evidence to suggest that BPA exposure in a predominantly low-income, minority pediatric cohort is associated with asthma morbidity and that associations may differ by sex. Our findings support additional studies, given the high pediatric asthma burden and widespread exposure to BPA in the United States., (Copyright © 2020 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.) more...

Background: Tropical cyclone epidemiology can be advanced through exposure assessment methods that are comprehensive and consistent across space and time, as these facilitate multiyear, multistorm studies. Further, an understanding of patterns in and between exposure metrics that are based on specific hazards of the storm can help in designing tropical cyclone epidemiological research., Objectives: a ) Provide an open-source data set for tropical cyclone exposure assessment for epidemiological research; and b ) investigate patterns and agreement between county-level assessments of tropical cyclone exposure based on different storm hazards., Methods: We created an open-source data set with data at the county level on exposure to four tropical cyclone hazards: peak sustained wind, rainfall, flooding, and tornadoes. The data cover all eastern U.S. counties for all land-falling or near-land Atlantic basin storms, covering 1996-2011 for all metrics and up to 1988-2018 for specific metrics. We validated measurements against other data sources and investigated patterns and agreement among binary exposure classifications based on these metrics, as well as compared them to use of distance from the storm's track, which has been used as a proxy for exposure in some epidemiological studies., Results: Our open-source data set was typically consistent with data from other sources, and we present and discuss areas of disagreement and other caveats. Over the study period and area, tropical cyclones typically brought different hazards to different counties. Therefore, when comparing exposure assessment between different hazard-specific metrics, agreement was usually low, as it also was when comparing exposure assessment based on a distance-based proxy measurement and any of the hazard-specific metrics., Discussion: Our results provide a multihazard data set that can be leveraged for epidemiological research on tropical cyclones, as well as insights that can inform the design and analysis for tropical cyclone epidemiological research. https://doi.org/10.1289/EHP6976. more...

Background: Current childhood asthma therapies have little effect on lung function trajectory., Objective: We sought to determine whether mouse allergen exposure reduction is associated with lung function growth in mouse-sensitized/exposed asthmatic children., Methods: Three hundred fifty mouse-sensitized/exposed asthmatic children (5-17 years old) were enrolled in a 1-year randomized trial of integrated pest management plus education versus education alone. Prebronchodilator/postbronchodilator spirometry was performed at baseline and 6 and 12 months, and bedroom floor mouse allergen levels were measured every 3 months. Mouse allergen reduction was defined as a 75% or greater decrease in mouse allergen levels from baseline. Treatment groups were combined for analyses because there were no differences in outcomes between groups. Changes in lung function over time were modeled, adjusting for age, sex, race, atopy, group, and bronchodilator reversibility and including an interaction term (allergen reduction*time)., Results: The study population was predominantly black (79.4%) and low income (66.3% [<$30,000]). At baseline, the median mouse allergen level was 5.7 μg/g (interquartile range, 1.5-22.8 μg/g), and the mean (SD) prebronchodilator FEV 1 /forced vital capacity ratio was 80.2% (9.0%). Ninety-two (26.3%) participants had 75% or greater reduction in mouse allergen levels. For a 10-year-old black boy, 75% or greater allergen reduction was associated with an increase in prebronchodilator FEV 1 of 238 mL/y (95% CI, 177-299 mL/y), whereas less than 75% allergen reduction was associated with an increase in prebronchodilator FEV 1 of 131 mL/y (95% CI, 97-166 mL/y). Estimated differences in prebronchodilator and postbronchodilator FEV 1 growth were as follows: 107 mL/y (95% CI, 37-177 mL/y; P int  = .003) and 48 mL/y (95% CI, -17 to 113 mL/y; P int  = .15), respectively. Estimated differences in prebronchodilator and postbronchodilator forced expiratory flow at 25% to 75% of vital capacity growth were as follows: 182 mL/y (95% CI, 61-304 mL/y; P int  = .003) and 181 mL/y (95% CI, 48-314 mL/y; P int  = .008), respectively., Conclusion: Mouse allergen reduction is associated with greater increases in prebronchodilator FEV 1 and prebronchodilator/postbronchodilator forced expiratory flow at 25% to 75% of vital capacity over 1 year among sensitized/exposed asthmatic children., (Copyright © 2019 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.) more...

Importance: Few studies have investigated the association of long-term ambient ozone exposures with respiratory morbidity among individuals with a heavy smoking history., Objective: To investigate the association of historical ozone exposure with risk of chronic obstructive pulmonary disease (COPD), computed tomography (CT) scan measures of respiratory disease, patient-reported outcomes, disease severity, and exacerbations in smokers with or at risk for COPD., Design, Setting, and Participants: This multicenter cross-sectional study, conducted from November 1, 2010, to July 31, 2018, obtained data from the Air Pollution Study, an ancillary study of SPIROMICS (Subpopulations and Intermediate Outcome Measures in COPD Study). Data analyzed were from participants enrolled at 7 (New York City, New York; Baltimore, Maryland; Los Angeles, California; Ann Arbor, Michigan; San Francisco, California; Salt Lake City, Utah; and Winston-Salem, North Carolina) of the 12 SPIROMICS clinical sites. Included participants had historical ozone exposure data (n = 1874), were either current or former smokers (≥20 pack-years), were with or without COPD, and were aged 40 to 80 years at baseline. Healthy persons with a smoking history of 1 or more pack-years were excluded from the present analysis., Exposures: The 10-year mean historical ambient ozone concentration at participants' residences estimated by cohort-specific spatiotemporal modeling., Main Outcomes and Measures: Spirometry-confirmed COPD, chronic bronchitis diagnosis, CT scan measures (emphysema, air trapping, and airway wall thickness), 6-minute walk test, modified Medical Research Council (mMRC) Dyspnea Scale, COPD Assessment Test (CAT), St. George's Respiratory Questionnaire (SGRQ), postbronchodilator forced expiratory volume in the first second of expiration (FEV1) % predicted, and self-report of exacerbations in the 12 months before SPIROMICS enrollment, adjusted for demographics, smoking, and job exposure., Results: A total of 1874 SPIROMICS participants were analyzed (mean [SD] age, 64.5 [8.8] years; 1479 [78.9%] white; and 1013 [54.1%] male). In adjusted analysis, a 5-ppb (parts per billion) increase in ozone concentration was associated with a greater percentage of emphysema (β = 0.94; 95% CI, 0.25-1.64; P = .007) and percentage of air trapping (β = 1.60; 95% CI, 0.16-3.04; P = .03); worse scores for the mMRC Dyspnea Scale (β = 0.10; 95% CI, 0.03-0.17; P = .008), CAT (β = 0.65; 95% CI, 0.05-1.26; P = .04), and SGRQ (β = 1.47; 95% CI, 0.01-2.93; P = .048); lower FEV1% predicted value (β = -2.50; 95% CI, -4.42 to -0.59; P = .01); and higher odds of any exacerbation (odds ratio [OR], 1.37; 95% CI, 1.12-1.66; P = .002) and severe exacerbation (OR, 1.37; 95% CI, 1.07-1.76; P = .01). No association was found between historical ozone exposure and chronic bronchitis, COPD, airway wall thickness, or 6-minute walk test result., Conclusions and Relevance: This study found that long-term historical ozone exposure was associated with reduced lung function, greater emphysema and air trapping on CT scan, worse patient-reported outcomes, and increased respiratory exacerbations for individuals with a history of heavy smoking. The association between ozone exposure and adverse respiratory outcomes suggests the need for continued reevaluation of ambient pollution standards that are designed to protect the most vulnerable members of the US population. more...

Epidemiological studies of wildfire PM 2.5 constituents are hindered by the limited information on the population exposure to ambient PM 2.5 constituents during high-pollution episodes from wildfires ("smoke waves"). The chemical composition of wildfire-related PM 2.5 can be affected by different ecosystems. Current literature assessing the differences in PM 2.5 pollution from wildfire smoke by ecosystems often analyzes air samples collected from the smoke near the center of an individual fire, but the results might not represent the exposure of the general public living away from the fire center but affected by the smoke of the fire. We assessed the population-based exposure to wildfire-related PM 2.5 species by integrating monitor measurements on 29 PM 2.5 species and previous findings on smoke waves during 2004-2009 in 51 Western US counties across six ecoregions. We found that across all ecoregions, smoke waves were associated with an increase in the fraction of organic carbon of total PM 2.5 by 20 percentage points (95% confidence interval (CI): 17, 23), an increase in the fraction of elemental carbon by 0.99 percentage points (95% CI: 0.43, 1.6), and decreases in fractions of sulfate and crustal species. While the PM 2.5 mixtures were dominated by the same source (wildfires), compositions in North American Deserts and the Great Plains during smoke waves were distinct. Besides expanding the knowledge of wildfire PM 2.5 , our study has implications beyond wildfires and could aid future population-based epidemiological research on PM 2.5 mixtures by source and region. more...

Heat waves are anticipated to worsen with climate change. India, an understudied area with >15% of the world's population, commonly experiences temperature extremes and already resembles potential future climates of more temperate regions. Registry data from local municipal corporations and government offices were collected and translated, yielding daily all-cause mortality for 4 communities in Northwest India for all or part of the period 2000-2012. Heat waves were defined as ≥2 days with local temperature ≥97th percentile for that community. An alternate definition matching that used by the Indian Meteorological Department was also developed, to enhance policy relevance. Community-specific average daily maximum temperature over the entire record ranged from 32.5 to 34.2 °C (90.5-93.6 °F). Across communities, total mortality increased 18.1% during heat wave days compared with non-heat-wave days [95% confidence interval (CI): -5.3%, 47.3%], with the highest risk in Jaipur (29.9% [95% CI: 24.6%, 34.9%]). Evidence of effect modification by heat wave characteristics (intensity, duration, and timing in season) was limited. Findings indicate health risks associated with heat waves in communities with high baseline temperatures. Results can inform heat wave-health assessments in temperate regions in future, and improve our understanding of temperature-health associations under climate change. Further investigation of potential effect modification by heat wave characteristics is needed., (Copyright © 2019 Elsevier Inc. All rights reserved.) more...