A novel risk-adjusted metric to compare hospitals on their antibiotic-prescribing at hospital discharge.

BACKGROUND: Antibiotic overuse at hospital discharge is common, but there is no metric to evaluate hospital performance at this transition of care. We built a risk-adjusted metric for comparing hospitals on their overall post-discharge antibiotic use. METHODS: This was a retrospective study across all acute-care admissions within the Veterans Health Administration during 2018-2021. For patients discharged to home, we collected data on antibiotics and relevant covariates. We built a zero-inflated negative binomial mixed-model with two random intercepts for each hospital to predict post-discharge antibiotic exposure and length of therapy (LOT). Data were split into training and testing sets to evaluate model performance using absolute error. Hospital performance was determined by the predicted random intercepts. RESULTS: 1,804,300 patient-admissions across 129 hospitals were included. Antibiotics were prescribed to 41.5% while hospitalized and 19.5% at discharge. Median LOT among those prescribed post-discharge antibiotics was 7 (IQR 4-10). The predictive model detected post-discharge antibiotic use with fidelity, including accurate identification of any exposure (area under the precision-recall curve=0.97) and reliable prediction of post-discharge LOT (mean absolute error = 1.48). Based on this model, 39 (30.2%) hospitals prescribed antibiotics less often than expected at discharge and used shorter LOT than expected. Twenty-eight (21.7%) hospitals prescribed antibiotics more often at discharge and used longer LOT. CONCLUSION: A model using electronically-available data was able to predict antibiotic use prescribed at hospital discharge and showed that some hospitals were more successful in reducing antibiotic overuse at this transition of care. This metric may help hospitals identify opportunities for improved antibiotic stewardship at discharge.

Occupational radiation dose trends in U.S. radiologic technologists assisting with fluoroscopically-guided interventional procedures, 1980-2020.

PURPOSE: To summarize dose trends from 1980-2020 for 19,651 U.S. radiologic technologists who reported assisting with fluoroscopically-guided interventional procedures (FGIP), overall and by work history characteristics. METHODS: We summarized 762,310 annual personal dose equivalents at a 10 mm-reference depth ("doses") during 1980-2020 for 43,823 participants of the U.S. Radiologic Technologists (USRT) cohort who responded to work history questionnaires administered during 2012-2014. This population included 19,651 technologists who reported assisting with FGIP (≥1 time per month for ≥12 consecutive months) at any time during the study period. We estimated doses corresponding to assistance with FGIP by proximity to patients, monthly procedure frequency, and procedure type. We used box plots and summary statistics (e.g., median, percentiles) to describe annual doses and dose trends. RESULTS: Median annual dose corresponding to assistance with FGIP was 0.65 mSv, [interquartile range (IQR)=0.60-1.40; 95th percentile=6.80]. Higher occupational doses with wider variability were associated with close proximity to patients during assistance with FGIP (median=1.20 mSv; IQR=0.60-4.18; 95th percentile=12.66), performing ≥20 FGIP per month (median=0.75 mSv; IQR=0.60, 2.40; 95th percentile=9.44), and assisting with high-dose FGIP (median=0.70; IQR=0.60, 1.90; 95th percentile=8.30). CONCLUSION: Occupational doses corresponding to assistance with FGIP were generally low but varied with exposure frequency, procedure type, and proximity to patients. These results highlight the need for vigilant dose monitoring, radiation safety training, and proper protective equipment.

Heat and Cold Wave-Related Mortality Risk among United States Veterans with Chronic Obstructive Pulmonary Disease: A Case-Crossover Study.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a heterogeneous pulmonary disease affecting 16 million Americans. Individuals with COPD are susceptible to environmental disturbances including heat and cold waves that can exacerbate disease symptoms. OBJECTIVE: Our objective was to estimate heat and cold wave-associated mortality risks within a population diagnosed with a chronic respiratory disease. METHODS: We collected individual level data with geocoded residential addresses from the Veterans Health Administration on 377,545 deceased patients with COPD (2016 to 2021). A time stratified case-crossover study was designed to estimate the incidence rate ratios (IRR) of heat and cold wave mortality risks using conditional logistic regression models examining lagged effects up to 7 d. Attributable risks (AR) were calculated for the lag day with the strongest association for heat and cold waves, respectively. Effect modification by age, gender, race, and ethnicity was also explored. RESULTS: Heat waves had the strongest effect on all-cause mortality at lag day 0 [IRR: 1.04; 95% confidence interval (CI): 1.02, 1.06] with attenuated effects by lag day 1. The AR at lag day 0 was 651 (95% CI: 326, 975) per 100,000 veterans. The effect of cold waves steadily increased from lag day 2 and plateaued at lag day 4 (IRR: 1.04; 95% CI: 1.02, 1.07) with declining but still elevated effects over the remaining 7-d lag period. The AR at lag day 4 was 687 (95% CI: 344, 1,200) per 100,000 veterans. Differences in risk were also detected upon stratification by gender and race. DISCUSSION: Our study demonstrated harmful associations between heat and cold waves among a high-risk population of veterans with COPD using individual level health data. Future research should emphasize using individual level data to better estimate the associations between extreme weather events and health outcomes for high-risk populations with chronic medical conditions. https://doi.org/10.1289/EHP13176.

Mortality and cancer incidence in perfluorooctanesulfonyl fluoride production workers.

BACKGROUND: Exposure to per- and polyfluoroalkyl substances (PFAS) has been associated with several health outcomes, though few occupationally-exposed populations have been studied. We evaluated mortality and cancer incidence in a cohort of perfluorooctanesulfonyl fluoride-based specialty chemical manufacturing workers. METHODS: The cohort included any employee who ever worked at the facility from 1961 to 2010 (N = 4045), with a primary interest in those who had 365 cumulative days of employment (N = 2659). Vital status and mortality records were obtained through 2014 and the cohort was linked to state cancer registries to obtain incident cancer cases from 1995 to 2014. Cumulative exposure was derived from a comprehensive exposure reconstruction that estimated job-specific perfluorooctanesulfonate (PFOS)-equivalents (mg/m3 ) exposure. Overall and exposure-specific standardized mortality ratios (SMR) were estimated in reference to the US population. Hazard ratios (HRs) and 95% confidence interval (CI) for cumulative PFOS-equivalent exposure (log2 transformed) were estimated within the cohort for specific causes of death and incident cancers using a time-dependent Cox model. RESULTS: Death rates were lower than expected except for cerebrovascular disease (SMR = 2.42, 95% CI = 1.25-4.22) and bladder cancer (SMR = 3.91, 95% CI = 1.07-10.02) in the highest exposure quartile. Within the cohort, the incidence of bladder, colorectal, and pancreatic cancer were positively associated with exposure, however except for lung cancer (HR = 1.05, 95% CI = 1.00-1.11) the CIs did not exclude an HR of 1. CONCLUSIONS: This study provides some evidence that occupational exposure to PFOS is associated with bladder and lung cancers and with cerebrovascular disease.

Continuation of Buprenorphine During Hospitalization and Subsequent Retention in Therapy: an Observational Study in Veterans Administration Hospitals.

BACKGROUND: Inpatient hospitalization has the potential to disrupt buprenorphine therapy. OBJECTIVE: Among patients receiving outpatient buprenorphine prior to admission, we determined the rate of discontinuation during medical and surgical admissions to VA hospitals and its association with subsequent post-discharge continuation of buprenorphine therapy. DESIGN AND MAIN MEASURES: We conducted an observational study using Veterans Administration data from 10/1/2018 to 3/31/2020 for all medical and surgical admissions where Veterans had active buprenorphine prescriptions at the time of admission. Pre-admission buprenorphine prescriptions were categorized as either sublingual (presumed indication for opioid use disorder (OUD)) or buccal/topical (presumed indication for pain). The primary measure of post-discharge buprenorphine receipt was any outpatient buprenorphine prescription dispensed between 1 day prior to discharge and 60 days following discharge. KEY RESULTS: A total of 830 unique inpatient hospitalizations to medical or surgical services occurred among Veterans receiving sublingual (48.3%) or buccal/topical (51.7%) buprenorphine prior to admission. Fewer than half (43.9%) of these patients received buprenorphine at some point during the medical or surgical portion of their hospital stay. Among the 766 patients discharged from a medical or surgical unit, 74.3% received an outpatient buprenorphine prescription within the 60 days following discharge (80.2% sublingual and 69.1% buccal/topical). Among patients who had received buprenorphine during the final 36 h prior to discharge, subsequent outpatient buprenorphine receipt was observed in 94.0%, compared to only 63.7% among those not receiving buprenorphine during the final 36 h (χ2 = 83.5, p < 0.001). CONCLUSION: Inpatient buprenorphine administrations near the time of discharge were highly predictive of continued outpatient therapy and a significant subset of patients did not continue or reinitiate buprenorphine therapy following discharge. As recommendations for perioperative and inpatient management of buprenorphine coalescence around continuation, efforts are needed to optimize hospital-based buprenorphine practices.

Temperature-related emergency injury visits in Hanoi, Vietnam.

BACKGROUND: The short-term association between increasing temperatures and injury has been described in high-income countries, but less is known for low-income and-middle-income countries, including Vietnam. METHODS: We used emergency injury visits (EIV) data for 2017-2019 from 733 hospitals and clinics in Hanoi, Vietnam to examine the effects of daily temperature on EIV. Time-series analysis with quasi-Poisson models was used to estimate a linear relative risk increase (RRI) for overall populations and ones stratified by age and sex. Exposure-response curves estimated non-linear associations as an RR between daily temperature and injury. Models were adjusted for the day of week, holidays, daily relative humidity, daily particulate matter, and long-term and seasonal trends. RESULTS AND CONCLUSIONS: A total of 39 313 EIV were recorded averaging 36 injuries daily. Injuries more likely occurred in males and those aged 15-44, and aged 44-60. For linear effects, a 5°C increase in same day mean temperature was associated with an overall increased EIV (RRI 4.8; 95% CI 2.3 to 7.3) with males (RRI 5.9; 95% CI 3.0 to 8.9) experiencing a greater effect than females (RRI 3.0; 95% CI -0.5 to 6.5). Non-linear effects showed an increase in EIV at higher temperatures compared with the threshold temperature of 15°C, with the greatest effect at 33°C (RR 1.3; 95% CI 1.2 to 1.6). Further research to investigate temperature-injury among different populations and by the cause of injury is warranted.

Procalcitonin Monitoring and Antibiotic Duration in Presumed Lower Respiratory Tract Infections: A Propensity Score-Matched Cohort Across the Veterans Health Administration.

Background: Randomized controlled trials have shown that procalcitonin-guided algorithms can reduce antibiotic duration for lower respiratory tract infections (LRTIs). The goal of this study was to compare antibiotic duration for LRTIs with and without procalcitonin testing in real-life practice. Methods: This retrospective cohort study included all acute care hospital admissions for presumed LRTIs between 1/2018 and 12/2021 at 81 Veterans Affairs facilities with on-site procalcitonin testing. The exposure was procalcitonin testing; the primary outcome was antibiotic duration. We used 1:1 nearest-neighbor propensity score matching to estimate the difference in outcome between procalcitonin-tested and nontested patients. Results: A total of 35 610 patients with LRTIs were included (6015 [16.9%] with procalcitonin testing; 29 595 [83.1%] without testing). In tested patients, the median number of procalcitonin levels checked (interquartile range) was 2 (1-3). The mean antibiotic duration was 10.0 days in the procalcitonin group compared with 8.3 days in nontested patients (unadjusted difference, 1.7 days; P < .0001). After propensity score matching with 3903 pairs, antibiotic duration remained greater in the procalcitonin group (9.6 days vs 9.2 days; P < .0001). In a subgroup analysis of 2241 tested patients with a procalcitonin value at the standard threshold for antibiotic discontinuation, antibiotic duration was shorter in tested vs nontested patients, with a mean difference of 0.1 days (P < .01). Conclusions: In this retrospective propensity-matched cohort of patients with presumed LRTIs across a geographically diverse group of hospitals, patients who underwent procalcitonin testing did not have a meaningful reduction in antibiotic duration compared with those who were not tested. Poor implementation of procalcitonin testing may have undermined its effectiveness.

Implementation of a Prevention Bundle to Decrease Rates of Staphylococcus aureus Surgical Site Infection at 11 Veterans Affairs Hospitals.

Importance: While current evidence has demonstrated a surgical site infection (SSI) prevention bundle consisting of preoperative Staphylococcus aureus screening, nasal and skin decolonization, and use of appropriate perioperative antibiotic based on screening results can decrease rates of SSI caused by S aureus, it is well known that interventions may need to be modified to address facility-level factors. Objective: To assess the association between implementation of an SSI prevention bundle allowing for facility discretion regarding specific component interventions and S aureus deep incisional or organ space SSI rates. Design, Setting, and Participants: This quality improvement study was conducted among all patients who underwent coronary artery bypass grafting, cardiac valve replacement, or total joint arthroplasty (TJA) at 11 Veterans Administration hospitals. Implementation of the bundle was on a rolling basis with the earliest implementation occurring in April 2012 and the latest implementation occurring in July 2017. Data were collected from January 2007 to March 2018 and analyzed from October 2020 to June 2023. Interventions: Nasal screening for S aureus; nasal decolonization of S aureus carriers; chlorhexidine bathing; and appropriate perioperative antibiotic prophylaxis according to S aureus carrier status. Facility discretion regarding how to implement the bundle components was allowed. Main Outcomes and Measures: The primary outcome was deep incisional or organ space SSI caused by S aureus. Multivariable logistic regression with generalized estimating equation (GEE) and interrupted time-series (ITS) models were used to compare SSI rates between preintervention and postintervention periods. Results: Among 6696 cardiac surgical procedures and 16 309 TJAs, 95 S aureus deep incisional or organ space SSIs were detected (25 after cardiac operations and 70 after TJAs). While the GEE model suggested a significant association between the intervention and decreased SSI rates after TJAs (adjusted odds ratio, 0.55; 95% CI, 0.31-0.98), there was not a significant association when an ITS model was used (adjusted incidence rate ratio, 0.88; 95% CI, 0.32-2.39). No significant associations after cardiac operations were found. Conclusions and Relevance: Although this quality improvement study suggests an association between implementation of an SSI prevention bundle and decreased S aureus deep incisional or organ space SSI rates after TJAs, it was underpowered to see a significant difference when accounting for changes over time.

Antibiotic prescribing in mental health units across the Veterans' Health Administration: How much and how appropriate?

We evaluated antibiotic-prescribing across 111 mental health units in the Veterans' Health Administration. We found that accurate diagnosis of urinary tract infections is a major area for improvement. Because non-mental-health clinicians were involved in most antibiotic-prescribing decisions, stewardship interventions for mental health patients should have a broad target audience to be effective.

Assessing Self-reported Occupational Hazards of Manure Applicators in the Upper Midwest.

Manure management on farms presents potential risks to human health and safety, including infectious, chemical, and physical exposures that may result in injury or fatality. Toxic gases and confined spaces are among the most common hazards. These hazards are especially salient for the Upper Midwest of the United States. This study characterizes the occupational health and safety practices and experiences of manure applicators in Minnesota. This cross-sectional study surveyed 162 commercial manure applicators about their work characteristics, safety practices, and health and safety experiences. Respondents reported an average of 17 hours per day applying manure during the busy season, which typically occurs several weeks each year. One hundred and thirty-one (90%) of 145 respondents did not regularly use gas monitors during application. Thirty-three (37%) of 90 respondents reported at least one symptom of gas exposure during manure application work. Those that worked with swine manure were more likely to report symptoms of gas exposure than those who did not work with swine (OR 9.5; CI: 2.0, 89.0). Those that had entered confined spaces were more likely to report symptoms of gas exposure than those who had not entered confined spaces (OR 4.4; CI: 0.1, 1.1). Fourteen (9%) of 150 respondents reported being injured when applying manure. Manure work can be hazardous and may be associated with injury and gas exposure. These findings offer a starting point for future research and intervention to protect and improve the health and safety of applicators.

Post-procedural Antibiotic Use and Associated Outcomes After Common Urologic Procedures Across a National Healthcare System.

OBJECTIVE: To quantify the benefits and harms of post-procedural antibiotic use after common urologic procedures. MATERIALS AND METHODS: This retrospective cohort study included patients who underwent an endoscopic urologic procedure (transurethral resection of bladder tumor, transurethral resection of prostate, or ureteroscopy) within the Veterans Health Administration between January 1, 2017 and June 30, 2021. A post-procedural antibiotic was any qualifying antibiotic prescribed for administration on the day after the procedure. Guidelines generally do not recommend post-procedural antibiotics for surgical prophylaxis. Outcomes included unplanned return visits and Clostridioides difficile infection within 30 days. Log-binomial models with risk-adjustment were used to measure the association between post-procedural antibiotic use and outcomes. Hospital-level observed-to-expected (O:E) ratios were constructed to compare post-procedural antibiotic use. RESULTS: There were 74,629 qualifying procedures across 105 hospitals; 27,422 (36.7%) received post-procedural antibiotics (median 3 days, IQR 3-6). An unplanned return visit occurred in 20.2% of patients who received post-procedural antibiotics vs 17.2% who did not (adjusted RR 1.032, 95% CI 0.999-1.066). C. difficile infection was diagnosed in 0.27% vs 0.10% in those who received and did not receive post-procedural antibiotics (adjusted RR 1.67, 95% CI 1.13-2.45). The O:E ratio for post-procedural antibiotic use ranged from 0.46 among hospitals in the lowest-use quartile to 1.93 in the highest-use quartile. CONCLUSION: Post-procedural antibiotics were frequently prescribed after urologic procedures with large inter-facility variability even after adjusting for case-mix differences. Post-procedural antibiotic use was associated with increased risk for C. difficile infection but not fewer unplanned return visits. Efforts to reduce guideline-discordant use of post-procedural antibiotics are needed.

The Effects of Daily Temperature on Crime Events in Urban Hanoi, Vietnam Using Seven Years of Data (2013-2019).

The effects of temperature on behavior change and mental health have previously been explored, but the association between temperature and crime is less well understood, especially in developing countries. Single-city-level data were used to evaluate the association between the short-term effects of temperature on crime events in urban Hanoi, Vietnam. We used quasi-Poisson regression models to investigate the linear effects and distributed lag non-linear models to investigate the non-linear association between daily temperature and daily crime events from 2013 to 2019. There were 3884 crime events, including 1083 violent crimes and 2801 non-violent crimes during the 7-year study period. For both linear and non-linear effects, there were positive associations between an increase in daily temperature and crime, and the greatest effects were observed on the first day of exposure (lag 0). For linear effects, we estimated that each 5 °C increase in daily mean temperature was associated with a 9.9% (95%CI: 0.2; 20.5), 6.8% (95%CI: 0.6; 13.5), and 7.5% (95%CI: 2.3; 13.2) increase in the risk of violent, non-violent, and total crime, respectively. For non-linear effects, however, the crime risk plateaued at 30 °C and decreased at higher exposures, which presented an inverted U-shape response with a large statistical uncertainty.

Effectiveness and Optimal Duration of Adjunctive Rifampin Treatment in the Management of Staphylococcus aureus Prosthetic Joint Infections After Debridement, Antibiotics, and Implant Retention.

Background: Rifampin is recommended as adjunctive therapy for patients with a Staphylococcus aureus prosthetic joint infection (PJI) managed with debridement, antibiotics, and implant retention (DAIR), with no solid consensus on the optimal duration of therapy. Our study assessed the effectiveness and optimal duration of rifampin for S aureus PJI using Veterans Health Administration (VHA) data. Methods: We conducted a retrospective cohort study of patients with S aureus PJI managed with DAIR between 2003 and 2019 in VHA hospitals. Patients who died within 14 days after DAIR were excluded. The primary outcome was a time to microbiological recurrence from 15 days up to 2 years after DAIR. Rifampin use was analyzed as a time-varying exposure, and time-dependent hazard ratios (HRs) for recurrence were calculated according to the duration of rifampin treatment. Results: Among 4624 patients, 842 (18.2%) received at least 1 dose of rifampin; 1785 (38.6%) experienced recurrence within 2 years. Rifampin treatment was associated with significantly lower HRs for recurrence during the first 90 days of treatment (HR, 0.60 [95% confidence interval {CI}, .45-.79]) and between days 91 and 180 (HR, 0.16 [95% CI, .04-.66]) but no statistically significant protective effect was observed with longer than 180 days (HR, 0.57 [95% CI, .18-1.81]). The benefit of rifampin was observed for subgroups including knee PJI, methicillin-susceptible or -resistant S aureus infection, and early or late PJI. Conclusions: This study supports current guidelines that recommend adjunctive rifampin use for up to 6 months among patients with S aureus PJI treated with DAIR.

Eligibility for and Use of Oral Antimicrobial Therapy Among Veterans With Osteoarticular Infections: A Retrospective Study Across 8 Medical Centers.

We retrospectively evaluated antimicrobial therapy in 145 randomly selected patients with osteoarticular infections across 8 hospitals. One hundred nine (75%) were eligible for oral antimicrobial therapy, but only 18 received it: 5 of 39 (13%) in 2018 versus 13 of 70 (19%) in 2019-2020 (P = .44). Oral antimicrobials may be underutilized for osteoarticular infections in routine practice.

Personalised paediatric chewable Ibuprofen tablets fabricated using 3D micro-extrusion printing technology.

Three-dimensional (3D) printing is becoming an attractive technology for the design and development of personalized paediatric dosage forms with improved palatability. In this work micro-extrusion based printing was implemented for the fabrication of chewable paediatric ibuprofen (IBU) tablets by assessing a range of front runner polymers in taste masking. Due to the drug-polymer miscibility and the IBU plasticization effect, micro-extrusion was proved to be an ideal technology for processing the drug/polymer powder blends for the printing of paediatric dosage forms. The printed tablets presented high printing quality with reproducible layer thickness and a smooth surface. Due to the drug-polymer interactions induced during printing processing, IBU was found to form a glass solution confirmed by differential calorimetry (DSC) while H-bonding interactions were identified by confocal Raman mapping. IBU was also found to be uniformly distributed within the polymer matrices at molecular level. The tablet palatability was assessed by panellists and revealed excellent taste masking of the IBU's bitter taste. Overall micro-extrusion demonstrated promising processing capabilities of powder blends for rapid printing and development of personalised dosage forms.

Ascertainment of Incident Cancer by US Population-Based Cancer Registries Versus Self-Reports and Death Certificates in a Nationwide Cohort Study, the US Radiologic Technologists Study.

Follow-up of US cohort members for incident cancer is time-consuming, is costly, and often results in underascertainment when the traditional methods of self-reporting and/or medical record validation are used. We conducted one of the first large-scale investigations to assess the feasibility, methods, and benefits of linking participants in the US Radiologic Technologists (USRT) Study (n = 146,022) with the majority of US state or regional cancer registries. Follow-up of this cohort has relied primarily on questionnaires (mailed approximately every 10 years) and linkage with the National Death Index. We compared the level of agreement and completeness of questionnaire/death-certificate-based information with that of registry-based (43 registries) incident cancer follow-up in the USRT cohort. Using registry-identified first primary cancers from 1999-2012 as the gold standard, the overall sensitivity was 46.5% for self-reports only and 63.0% for both self-reports and death certificates. Among the 37.0% false-negative reports, 27.8% were due to dropout, while 9.2% were due to misreporting. The USRT cancer reporting patterns differed by cancer type. Our study indicates that linkage to state cancer registries would greatly improve completeness and accuracy of cancer follow-up in comparison with questionnaire self-reporting. These findings support ongoing development of a national US virtual pooled registry with which to streamline cohort linkages.

Use of Nonsteroidal Anti-Inflammatory Drugs and Incidence of Melanoma in the United States Radiologic Technologists Study.

Although NSAIDs have been associated with both reduced and increased cutaneous melanoma risk, few studies have examined these associations by ultraviolet radiation (UVR) or personal sun-sensitivity. We examined the associations between NSAID use and first primary invasive cutaneous melanoma among 58,227 non-Hispanic white participants in the United States Radiologic Technologists cohort study. Poisson regression was used to calculate rate ratios (RR) and 95% likelihood-based confidence intervals (CI), adjusting for attained age, birth cohort, and ambient UVR. No significant association of melanoma was observed for any use of NSAIDs (RR, 0.87; 95% CI, 0.71-1.09). The relative risks of melanoma for the highest categories of aspirin and other NSAID use (≥5 times per month vs. none) were 0.93 (95% CI, 0.74-1.16) and 1.02 (95% CI, 0.83-1.25), respectively. Further analyses did not reveal dose-response for trends in frequency of NSAID use or interactions with sex, UVR, eye and hair color, and skin complexion. In this large nationwide study, NSAID use was not associated with melanoma risk. PREVENTION RELEVANCE: NSAIDs have been associated with both reduced and increased melanoma risk. However, few studies have examined the role of UVR or personal sun-sensitivity on these associations. Our findings strengthen the evidence that NSAID use is not associated with melanoma risk, even in sun-sensitive subgroups.

Reproductive factors, hormone use, and incidence of melanoma in a cohort of US Radiologic Technologists.

STUDY QUESTION: Are reproductive factors and exogenous hormone use associated with incidence of cutaneous melanoma while accounting for ultraviolet radiation (UVR) exposure across different life periods and sun sensitivity factors? SUMMARY ANSWER: Earlier age at menarche and late age at first birth, but not other estrogen-related factors were associated with an increased incidence rate of melanoma, with higher risks observed for earlier age at menarche and light hair color at age 15 years. WHAT IS KNOWN ALREADY: Although estrogens have been recognized as photosensitizing, previous studies have reported inconsistent findings for the association of melanoma with estrogen-related factors. Most have not collected detailed skin cancer risk factors and have not thoroughly investigated effect modification by ambient UVR and sun sensitivity. STUDY DESIGN, SIZE, DURATION: Participants in the US Radiologic Technologists study, an occupational cohort of 146 022 radiologic technologists (73% women), were included and followed during the four time periods (1983-1989, 1994-1998, 2003-2005 and 2012-2014). PARTICIPANTS/MATERIALS, SETTING, METHODS: Non-Hispanic white female participants who completed both the second (baseline) and third questionnaires, and did not report having cancer (except keratinocyte carcinoma) at baseline, were included and followed from their age at completion of the second (baseline) questionnaire until the earlier of first primary cancer diagnosis, including invasive melanoma of the skin, or completion of either the third or fourth questionnaire. Reproductive and exogenous hormonal factors were ascertained from the second (baseline) questionnaire, which also collected information on demographic, lifestyle factors and sun sensitivity factors. Ambient UVR was assigned by linking geocoded residential locations, based on self-reported residential history information collected from the third questionnaire to satellite-based ambient UVR data from the National Aeronautics and Space Administration's Total Ozone Mapping Spectrometer database. To examine the association of reproductive factors, exogenous hormone use, and first primary invasive melanoma of the skin, we used Poisson regression to calculate rate ratios (RRs) and 95% likelihood-based CIs, adjusting for attained age, birth cohort, lifetime average annual ambient UVR, contraceptives and menopausal hormone therapy use. To address the effect modification of ambient UVR exposure and sun sensitivities on melanoma risk, we conducted likelihood-ratio tests for multiplicative interaction. MAIN RESULTS AND THE ROLE OF CHANCE: Over a median follow-up time of 17.1 years, 0.95% of eligible participants had an incident first primary melanoma (n = 444). Higher melanoma incidence rates were observed in participants with older attained age, blue/green/gray eye color, blonde/red/auburn natural hair color at age 15, fair skin complexion, and higher UVR. We found an increased incidence rate of melanoma in women who experienced menarche at an earlier age (13, 12 and <12 years vs ≥14 years: RR = 1.48, 95% CI = 1.11-1.98; 1.19, 0.89-1.61; 1.26, 0.93-1.73), and in women with older age at first birth (25-29 and ≥30 years vs <25 years; 1.09, 0.86-1.39; 1.48, 1.12-1.95; P-value for trend = 0.006). However, no significant association was observed for other reproductive factors, and for all exogenous hormone use. The associations of melanoma incidence for most reproductive factors and exogenous hormone use were not modified by ambient UVR, eye color, natural hair color at age 15 and skin complexion. The exception was that natural hair color at age 15 modified the associations of melanoma for age at menarche (P-value for interaction = 0.004) and age at first birth among parous women (0.005). In participants with blonde/red/auburn natural hair color at age 15, we found increased risk of melanoma among women who experienced menarche at age 13, 12 and <12 years (vs ≥14 years: RR = 3.54, 95% CI = 1.98-6.90; 2.51, 1.37-4.98; 2.66, 1.41-5.36, respectively; P-value for trend = 0.10). However, the association between age at menarche and melanoma was null in participants with brown/black natural hair color at age 15. LIMITATIONS, REASONS FOR CAUTION: Information on reproductive history and exogenous hormone use was self-reported. We did not have information on specific doses or formulations of exogenous hormone medications or breastfeeding. WIDER IMPLICATIONS OF THE FINDINGS: Women residing in areas of high ambient UVR and those with blonde/red/auburn natural hair color may constitute an additional high-risk group in need of more frequent skin cancer screening. Identifying susceptible periods of exposure or factors that modify UVR susceptibility may aid in guiding more targeted guidelines for melanoma prevention. STUDY FUNDING/COMPETING INTEREST(S): This research was supported by the Intramural Research Program, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, US Department of Health and Human Services. Authors declare no conflict of interest. TRIAL REGISTRATION NUMBER: N/A.

Reconstructing Historical Exposures to Respirable Dust and Respirable Silica in the Taconite Mining Industry for 1955-2010.

The goal of this study was to reconstruct the historical respirable silica (RS) and respirable dust (RD) exposures of workers in the Minnesota taconite industry from 1955 to 2010 as part of several epidemiological studies for assessing the association between exposure to components of taconite dusts and the development of respiratory diseases. A job-exposure matrix (JEM) was developed that uses 9127 RS and 19 391 RD occupational hygiene historical measurements. Historical RS and RD data were extracted from several sources and were grouped into seven mines and then into eight departments [Concentrating, Crushing, Janitor, Mining, Office/control room, Pelletizing, Shop (mobile), and Shop (stationary)]. Within each department, we applied a two-level random-intercept regression model which assumes that the natural log of Y (RD or RS concentration) changes over time at a constant rate. Among all predicted RD and RS values, we found that larger RD values were located in the following departments: Crushing, Concentrating, Pelletizing, and Shop (mobile). Larger RS values were located only in either Crushing or Shop (mobile). The annual rates of change for historical RD and RS exposures were between -3.3 and 3.2%. The silica percentage in the dust varied by mine/department with the highest value of 29.3% in Mine F (Crushing) and the lowest value of 2.1% in Mine B (Pelletizing). The predicted historical RD and RS arithmetic mean exposures ranged between <0.075 and 3.14 mg m-3, and between <0.005 and 0.36 mg m-3, respectively. The result of this study is a JEM by mine, department, and year for RD and RS for epidemiological studies.