Fungal Depletion Bolsters Anti-Tumor Immune Response Elicited by Anti-PD1 Alone and in Combination with Radiation Therapy

PURPOSE/OBJECTIVE(S)

Pembrolizumab in combination with chemotherapy has become the standard of care treatment for both metastatic and early-stage triple negative breast cancer (TNBC). Clinical trials are currently underway investigating the use of pembrolizumab with radiation in the neoadjuvant setting in early TNBC. Several groups have described a link between the microbiome and the efficacy of chemotherapy and anti-PD1 immune checkpoint inhibitors (ICIs) in preclinical models. Recent work from our lab has shown that targeting commensal fungi in the microbiome enhances the radiation induced antitumor immune response. Therefore, we hypothesized that fungal depletion might positively impact anti-PD1 therapy and combination treatment with anti-PD1 and radiation therapy (RT).

MATERIALS/METHODS

This study utilized an orthotopic syngeneic breast tumor model in which the syngeneic cell line E0771 was injected into the mammary fat pad of female C57BL/6 mice. Tumor-bearing mice were then treated with and without the antifungal fluconazole, anti-PD1, and radiation (16 Gy single fraction) using the X-RAD SmART platform with CT guidance. Tumor volumes were compared using 2-way ANOVA and survival curves analyzed using log rank. In a separate set of experiments, tumor-infiltrating immune cells were isolated and analyzed by high-dimensional multiplex flow cytometry.

RESULTS

We found that fungal depletion with fluconazole prior to treatment with anti-PD1 reduced the tumor volume and significantly improved survival in comparison to those treated with anti-PD1 alone (P = 0.0016). To identify what changes in the tumor immune microenvironment is driving this increased anti-tumor response, we performed flow cytometry on immune cells isolated from the tumors. We found that the use of fluconazole prior to anti-PD1 treatment reduced the proportion of CD11b+F4/80+ tumor-associated macrophages (TAMs) (P = 0.01) and increased tumor infiltrating cytotoxic T cell population (P = 0.04) when compared with the use of anti-PD1 alone. We also evaluated the effect of fungal depletion on combination therapy with RT and anti-PD1. Strikingly, we found that mice depleted of fungi with fluconazole prior to radiation and anti-PD1 therapy, have decreased tumor burden and significantly increased survival when compared to their fungally-intact counterparts (P = 0.043).

CONCLUSION

Our data indicates that the depletion of the gut fungal populations induces an increased antitumor response following anti-PD1 alone and in combination with radiation. This increased antitumor immune response is associated with an increase in the cytotoxic CD8+ T cell compartment with concomitant decrease in immunosuppressive tumor associated macrophages.

Non-Redundant Mechanisms of Immune Resistance to Radiotherapy Converge on Innate Immunity

PURPOSE/OBJECTIVE(S)

Despite evidence of preclinical synergy between radiotherapy (RT) and immune checkpoint blockade (ICB), randomized trials of RT/ICB have demonstrated limited benefit in solid tumors. We performed single-cell RNA sequencing (scRNA-seq) and CITE-seq (cellular indexing of transcriptomes and epitopes) to address the discordance between preclinical and clinical data. We hypothesized that multiple orthogonal inhibitory immune pathways restrain the local and systemic efficacy of RT beyond T-cell oriented immune checkpoints.

MATERIALS/METHODS

We used the EO771 syngeneic murine model of breast cancer to characterize the immune tumor microenvironment following RT with or without ICB. RT (16 Gy x 1) was delivered using the X-RAD SmART platform with CT image guidance. Neutralizing antibodies (anti-PD-1/Ly6G/Gr-1/CD47) were delivered by intraperitoneal injections. scRNA-seq analysis were performed by Seurat and BBrowser (BioTuring).

RESULTS

We found that adaptive ICB (anti-PD-1) reprogrammed the immune response to RT by promoting an M1-like interferon-primed state (ISG15, CXCL10) in tumor associated macrophages (TAMs) and by increasing the late recruitment of intratumoral neutrophils. Given that neutrophils may drive resistance to RT in other models, we evaluated the effect of intratumoral neutrophil depletion using anti-Ly6G or anti-Gr-1 on the antitumor efficacy of RT/ICB. Both neutrophil depletion strategies led to enhanced tumor control and improved survival in advanced EO771 tumors compared to RT/ICB alone (P<0.001). In parallel to this approach, we found that TAMs upregulated several innate immune checkpoints including SIRPα in response to RT. Disruption of the SIRPα-CD47 interaction by anti-CD47 antibodies similarly enhanced the antitumor efficacy of RT/ICB by improving tumor control and survival (P<0.001). Using scRNA-seq and unbiased clustering, we found that anti-CD47 eliminated an entire cluster of chronically inflamed TAMs, characterized by pro-inflammatory markers (IL1A, NOS2) and chemokines (CCL3, CXCL1/2/3). Anti-CD47 also reduced intratumoral neutrophils by eliminating a cluster of pathologically activated neutrophils, termed myeloid-derived suppressor cells (PMN-MDSCs) that expressed several markers of ferroptosis (TFRC, PTGS2, SLC3A2). Consistent with the potent immunosuppressive capacity of PMN-MDSCs, we found that anti-CD47 increased tumor-infiltrating lymphocytes including central memory TCF7+ T cells and CD19+ B cells. Lastly, by inference and analysis of cell-cell communication (CellChat), we found that anti-CD47 strengthened the interactions between TAMs and CD8+ T cells compared to RT/ICB alone.

CONCLUSION

Our data collectively indicate that resistance to RT/ICB in the EO771 model Is driven by innate immune cells including neutrophils and chronically inflamed TAMs. Targeted disruption of the CD47-SIRPα axis is a promising approach to overcoming immune resistance by reprogramming TAMs and eliminating PMN-MDSCs.

Reshaping Macrophage Polarization Potential Enhances Antitumor Immune Response to Radiation Therapy

PURPOSE/OBJECTIVE(S)

Although radiation therapy (RT) remains a cornerstone in the treatment of breast cancer, many trials combining RT with immune checkpoint blockade (ICB) have failed to demonstrate benefit in solid tumors including breast cancer. Maximal efficacy of RT relies on the generation of antitumor immunity following treatment which largely consists of cytotoxic T cells and macrophages. Broad depletion of macrophages modestly enhances tumor responses to RT suggesting that they can shape RT-induced antitumor immunity. Although IL4 signaling through GATA-3 is known to polarize T cells into the protumor Th2 phenotype, such central drivers of macrophage polarization are not well established. Given that macrophages abundantly express IL4 receptor, we hypothesized that GATA-3 may direct the transition of macrophages to M2/alternative phase and that genetic ablation of GATA-3 in macrophages can enhance antitumor immunity by arresting macrophage transition to an M2-like pro-tumor state.

MATERIALS/METHODS

We generated a macrophage specific GATA-3 KO mouse model (mG3KO) driven by the LysM-Cre promoter. Using a syngeneic orthotopic murine model of breast cancer (EO771), we evaluated the differential effect of RT (16Gy x 1) in WT and mG3KO mice. Multiparametric flow cytometry was performed to investigate the immune changes within the tumor microenvironment on day 3, day 5 and day 10 after RT. T cell depletion was performed using antibodies to CD4 and CD8 by intraperitoneal injections to understand the role of adaptive immunity in the response to RT in WT and mG3KO mice.

RESULTS

We found that mG3KO mice bearing advanced EO771 tumors demonstrated significantly improved tumor regression compared to WT mice (p<0.001), which translated to increased overall survival. In vitro characterization of bone-marrow derived macrophages from mG3KO and WT mice suggest that macrophages with ablated GATA-3 expressed increased levels of iNOS and decreased levels of Arginase (Arg-1), consistent with an M1-like phenotype. Immune profiling of the tumors also revealed that mGATA-3 KO animals have significant enrichment of CD8+ T cells in the tumor milieu post RT and these CD8+ T cells express higher amounts of interferon gamma (p<0.001) and Granzyme B (p<0.0015) than their WT counterparts. Using neutralizing antibodies to deplete CD8+ T cells, we show that anti-tumor effects in the mG3KO mice were abolished, suggesting that mG3KO macrophages impact survival, at least, in part by enhancing cytotoxic CD8+T cells. Studies are currently ongoing to reveal the detailed mechanism of GATA-3 ablation in improving the efficacy of RT.

CONCLUSION

Our data indicates that GATA-3 is a central regulator of macrophage polarization in response to RT. Further, directed ablation of GATA-3 appears to drive macrophages towards an M1-like phenotype, which enhances T cell recruitment to irradiated tumors. These data suggest that the antitumor efficacy of RT can be prolonged by targeting GATA-3-dependent signaling within myeloid cells.

Perioperative fluid management in children: an updated review

Background: Perioperative fluid management in children has been a major topic for debate. Objectives: Our aim is to review the current evidence on perioperative fluid management in children including: type of fluid, administration rates, preoperative fluid intake and monitoring techniques. Design: Narrative review. Method: Following the PRISMA-S guidelines we performed a search (2010-March 2022) in databases Medline (through PubMed) and Cochrane Library. 4297 citations were found and screened by two independent researchers. After screening, 64 articles were withheld for our review. Results: The perioperative administration of isotonic fluids is safer than hypotonic solutions, concerning the development of hyponatremia. A balanced isotonic solution with 1-2,5% glucose should be used as perioperative maintenance IV fluid in children (1 month to 18 years). Colloids can be used in children when inadequate effect in volume correction is achieved with crystalloids. The preferred synthetic colloid for children is a third generation HES in a balanced solution. To date, most clinicians use the “4-2-1 rule” for calculating fluid rate. This may not be the optimal fluid rate, as little research has been done. Preoperative fasting for clear fluids should be limited to 1 hour, children should even be encouraged to drink up until 1 hour before induction. Respiratory variation of aortic blood flow peak velocity (ΔVpeak) with echocardiography is currently the most reliable technique for evaluating fluid responsiveness in children.

Individually experienced heat index in a coastal Southeastern US city among an occupationally exposed population

Recent studies have characterized individually experienced temperatures or individually experienced heat indices, including new exposure metrics that capture dimensions of exposure intensity, frequency, and duration. Yet, few studies have examined the personal thermal exposure in underrepresented groups, like outdoor workers, and even fewer have assessed corresponding changes in physiologic heat strain. The objective of this paper is to examine a cohort of occupationally exposed grounds and public safety workers (n = 25) to characterize their heat exposure and resulting heat strain. In addition, a secondary aim of this work is to compare individually heat index exposure (IHIE) across exposure metrics, fixed-site in situ weather stations, and raster-derived urban heat island (UHI) measurements in Charleston, SC, a humid coastal climate in the Southeastern USA. A Bland-Altman (BA) analysis was used to assess the level of agreement between the personal IHIE measurements and weather-station heat index (HI) and Urban Heat Island (UHI) measurements. Linear mixed-effect models were used to determine the association between individual risk factors and in situ weather station measurements significantly associated with IHIE measurements. Multivariable stepwise Cox proportional hazard modeling was used to identify the individual and workplace factors associated with time to heat strain in workers. We also examined the non-linear association between heat strain and exposure metrics using generalized additive models. We found significant heterogeneity in IHIE measurements across participants. We observed that time to heat strain was positively associated with a higher IHIE, older age, being male, and among Caucasian workers. Important nonlinear associations between heat strain occurrence and the intensity, frequency, and duration of personal heat metrics were observed. Lastly, our analysis found that IHIE measures were significantly similar for weather station HI, although differences were more pronounced for temperature and relative humidity measurements. Conversely, our IHIE findings were much lower than raster-derived UHI measurements. Real-time monitoring can offer important insights about unfolding temperature-health trends and emerging behaviors during thermal extreme events, which have significant potential to provide situational awareness.

Impact of an osteopathic peer recovery coaching model on treatment outcomes in high-risk men entering residential treatment for substance use disorders

CONTEXT

The United States has witnessed a disproportionate rise in substance use disorders (SUD) and co-occurring mental health disorders, paired with housing instability, especially among racially minoritized communities. Traditional in-patient residential treatment programs for SUD have proven inconsistent in their effectiveness in preventing relapse and maintaining attrition among these patient populations. There is evidence showing that peer recovery programs led by individuals who have lived experience with SUD can increase social support and foster intrinsic motivation within participants to bolster their recovery. These peer recovery programs, when coupled with a standardized training program for peer recovery coaches, may be very efficacious at improving patient health outcomes, boosting performance on Substance Abuse and Mental Health Services Administration (SAMHSA) national outcome measures (NOMs), and helping participants build an overall better quality of life.

OBJECTIVES

The goal of this study is to highlight the efficacy of a peer recovery program, the Minority Aids Initiative, in improving health outcomes and associated NOMs in men with SUD and/or co-occurring mental health disorder.

METHODS

Participants received six months of peer recovery coaching from trained staff. Sessions were guided by the Manual for Recovery Coaching and focused on 10 different domains of recovery. Participants and coaches set long-term goals and created weekly action plans to work toward them. Standardized assessments (SAMHSA's Government Performance and Results Act [GPRA] tool, Addiction Severity Index [ASI]) were administered by recovery coaches at intake and at the 6-month time point to evaluate participant progress. Analyses of participant recovery were carried out according to SAMHSA's six NOMs and assessed the outcomes of the intervention and their significance.

RESULTS

A total of 115 participants enrolled in the program over a 2-year period. Among them, 53 were eligible for 6-month follow-up interviews. In total, 321 sessions were held, with an average of three sessions per participant. Participants showed marked improvement across five of the six NOMs at the end of the 6-month course and across all ASI outcomes, with the exception of three in which participants reported an absence or few symptoms at intake.

CONCLUSIONS

Our study shows that participants receive benefits across nearly all NOM categories when paired with recovery coaches who are well trained in medication-assisted treatment (MAT) and medications for opioid use disorder (MOUD) over a 6-month period. We see the following: a higher rate of abstinence; increased housing stability; lower health, behavioral, and social consequences; lower depression and anxiety; longer participant-recovery coach exposure time; and higher follow-up rates. We hope that our results can contribute to advancements and greater acceptance in the implementation of peer recovery coaching as well as an improvement in the lives of the communities affected by substance use.

Long-Term Impact of a Low-Cost Paediatric Intussusception Air Enema Reduction Simulation-Based Education Programme in a Low-Middle Income Country

INTRODUCTION

Intussusception is one of the commonest causes of bowel obstruction in infants. Most infants in Low- and Middle-Income Countries (LMICs) undergo an invasive operative intervention. Supported by simulation-based education (SBE), the Air Enema (AE) non-operative technique was introduced in 2016 in Myanmar. This study assesses the long-term outcomes.

METHODS

Mixed methods study design over 4 years including clinical outcomes and surgeon's attitudes towards the AE technique and SBE. Prospectively collected clinical outcomes and semi-structured interview with reflexive thematic analysis (RTA). Primary outcome measure was a long-term shift to non-operative intervention.

SECONDARY OUTCOMES

Length of Stay (LoS), recurrence rates, intestinal resection rates, compared to the operative group. The data was analysed according to intention to treat. Quantitative data analysis with Mann-Whitney U test, Fisher's exact test, Student's T-Test or Wilcoxon Signed-Rank Test utilised. A p-value of <.05 was considered significant.

RESULTS

A total of 311 infants with intussusception were included. A sustained shift to AE was revealed with high success rates (86.1-91.2%). AE had a reduced LoS (4 vs. 7 days p ≤ 0.0001), Duration of Symptoms (DoS) was lower with AE (1.9/7 vs. 2.5/7, p = 0.002). Low recurrence rates (0-5.8%) and intestinal resection rates stabilised at 30.5-31.8% vs.15.3% pre-intervention. Four RTA themes were identified: Expanding conceptions of healthcare professional education and training; realising far reaching advantages; promoting critical analysis and reflective practice of clinicians; and adapting clinical practice to local context. RTA revealed an overall positive paradigm shift in attitudes and application of SBE.

CONCLUSIONS

A sustained change in clinical outcomes and appreciation of the value of SBE was demonstrated following the intervention.

POS1412 IDENTIFYING HIGH-COST DRUGS FOR RARE RHEUMATIC DISEASES IN ROUTINELY COLLECTED NHS DATA. RESULTS FROM A PILOT STUDY OF RITUXIMAB USE IN VASCULITIS USING DATA FROM THE NATIONAL DISEASE REGISTRATION SERVICE AND THE REGISTRATION OF COMPLEX RARE DISEASES-EXEMPLARS IN RHEUMATOLOGY (RECORDER) PROJECT

Background:

Understanding real-world usage of high-cost drugs is crucial to support planning, adoption of innovation and reduce unwarranted variation in treatment. Hospital Episode Statistics (HES) contain diagnoses (coded by ICD-10) and procedures/treatments (coded by OPCS) for all daycase or inpatient care in England. However, OPCS codes are not specific for individual drugs, for example X921 (cytokine inhibitors band 1) includes rituximab (RTX) and 15 other drugs.

Objectives:

We aimed to validate the accurate identification of patients treated with RTX for ANCA-associated vasculitis (AAV) using HES data.

Methods:

We used data from the National Congenital Anomaly and Rare Disease Registration Service (NCARDRS) at Public Health England and their legal permissions (CAG 10-02(d)/2015). We extracted records from HES of all patients treated at two hospitals during financial year 2018/19 who ever had a coded diagnosis of granulomatosis with polyangiitis (GPA, M313), eosinophilic granulomatosis with polyangiitis (EGPA, M301), microscopic polyangiitis (MPA, M317), polyarteritis nodosa (PAN, M300) or arteritis unspecified (I776). Where people had multiple diagnoses of vasculitis, the most specific was considered their diagnosis. Enabled by data sharing agreements, we reviewed hospital records of those patients to validate diagnoses and whether X921 reliably identified RTX. We report the positive predictive value and sensitivity of the coding for X921 and GPA/EGPA/MPA for identifying people with AAV who are treated with RTX.

Results:

At Trust 1 records ever coded with GPA/EGPA/MPA identified 74 people, 69 of whom had AAV confirmed in their medical notes. Among these 74 patients there were 59 episodes coded with X921 procedure codes, of which 56 correctly identified a RTX infusion given for AAV. A total of 64 RTX infusions were given to people with AAV – 3 missed infusions were X921 procedures in patients who had coded diagnoses of PAN or I776 but never GPA/EGPA/MPA and 5 infusions were not coded as X921.

The same analysis at Trust 2 identified 46 people, 44 of whom had AAV confirmed in their medical notes. Among patients identified with AAV there were 17 episodes coded as X921, of which 15 correctly identified a RTX infusion. A total of 23 infusions were given to people with AAV: 4 infusions were X921 procedures in patients who had coded diagnoses of PAN or I776 but never GPA/EGPA/MPA, and 4 infusions were not coded as X921.

Table 1.

Summary of Positive Predictive Values (PPV) applying our algorithm to identify AAV diagnoses and RTX use

Trust 1Trust 2CombinedDiagnosis of AAV and coded as AAV6944113AAV coded7446120Diagnosis of AAV under any code7355128PPV AAV ascertainment (95% CI)93.2% (84.9-97.8)95.7% (85.2-99.5)94.2% (88.4-97.6)Sensitivity of AAV ascertainment (95% CI)94.5% (86.8-98.5)80.0% (67.0-89.6)88.3% (81.4-93.3)RTX given in people coded as AAV561571RTX coded in people coded as AAV591776RTX given for AAV under any diagnostic or procedure code642387PPV RTX ascertainment (95% CI)94.9% (85.9-98.9)88.2% (63.6-98.5)93.4% (85.3-97.8)Sensitivity of RTX ascertainment (95% CI)87.5% (76.8-94.4)65.2% (42.7-83.6)81.6% (71.9-89.1)

Conclusion:

HES data identified patients treated with RTX for AAV with a PPV of 93.4% (85.3-97.8) and sensitivity of 81.6% (71.9-89.1). This demonstrates the utility of national data to identify people receiving RTX for AAV. The RECORDER project, within the National Disease Registration Service plans to conduct real-world studies of the high-cost drug RTX, given for AAV, across the whole of England, and assess whether geography, demographics or socioeconomic factors influence frequency of prescription of this, and potentially other, high-cost drugs in line with the NHS long term plan.

References:

[1]Ward-Platt M, Stevens S, Miller N. I18 The national congenital anomaly and rare disease registration service (NCARDRS): The first year

Acknowledgements:

I have no acknowledgements to declare.

Disclosure of Interests:

Cattleya Godsave: None declared, Mithun Chakravorty: None declared, Megan Rutter: None declared, Peter Lanyon Grant/research support from: P.C.L. is a recipients of a grant from Vifor Pharma. Vifor Pharma had no influence on the design, conduct or interpretation of this study., Jeanette Aston: None declared, Mary Bythell: None declared, Sarah Stevens: None declared, Fiona Pearce Grant/research support from: I have received a research grant from Vifor Pharma

851 SMILE: Sustaining Medical Education in A Lockdown Environment. Student Perceptions of a Free Online Access Medical Education Platform as An Adjunct to The Traditional Undergraduate Curriculum During Lockdown

Introduction

The coronavirus outbreak has had significant impact on medical students worldwide. SMILE is a free online access medical education (FOAMEd) platform. SMILE delivered 200 lectures during lockdown with up to 1400 students per session from UK medical schools and 33 abroad. Here we discuss student perceptions to SMILE during lockdown

Method

A survey was used to collect information from students who had utilised the platform during lockdown. This examined access to learning, impact on mental health during lockdown and the differences between FOAMed and more traditional based campus lecture-based learning.

Results

1306 students responded to the survey. The majority of students were concerned regarding their training during lockdown, with 71% reporting an impact on their stress levels and 44% reporting a negative impact on mental health.

On average students attended 4.3hours of teaching put on by their university per week, vs 7.9hours by SMILE.

Positives included anonymity, making 80% more likely to both ask and answer questions, the informal approach, ease of access and enthusiastic teachers. Negatives included time differences and technical issues.

Conclusions

Lockdown provided challenges in medical education, which platforms like SMILE addressed. Our experiences highlighted many positive outcomes of online medical education that may be applicable to other educators.

Prevalence of Down's Syndrome in England, 1998-2013: Comparison of linked surveillance data and electronic health records

INTRODUCTION

Disease registers and electronic health records are valuable resources for disease surveillance and research but can be limited by variation in data quality over time. Quality may be limited in terms of the accuracy of clinical information, of the internal linkage that supports person-based analysis of most administrative datasets, or by errors in linkage between multiple datasets.

OBJECTIVES

By linking the National Down Syndrome Cytogenetic Register (NDSCR) to Hospital Episode Statistics for England (HES), we aimed to assess the quality of each and establish a consistent approach for analysis of trends in prevalence of Down's syndrome among live births in England.

METHODS

Probabilistic record linkage of NDSCR to HES for the period 1998-2013 was supported by linkage of babies to mothers within HES. Comparison of prevalence estimates in England were made using NDSCR only, HES data only, and linked data. Capture-recapture analysis and quantitative bias analysis were used to account for potential errors, including false positive diagnostic codes, unrecorded diagnoses, and linkage error.

RESULTS

Analyses of single-source data indicated increasing live birth prevalence of Down's Syndrome, particularly in the analysis of HES. Linked data indicated a contrastingly stable prevalence of 12.3 (plausible range: 11.6-12.7) cases per 10 000 live births.

CONCLUSION

Case ascertainment in NDSCR improved slightly over time, creating a picture of slowly increasing prevalence. The emerging epidemic suggested by HES primarily reflects improving linkage within HES (assignment of unique patient identifiers to hospital episodes). Administrative data are valuable but trends should be interpreted with caution, and with assessment of data quality over time. Data linkage with quantitative bias analysis can provide more robust estimation and, in this case, stronger evidence that prevalence is not increasing. Routine linkage of administrative and register data can enhance the value of each.

Wearable sensors for personal temperature exposure assessments: A comparative study

The impacts of heat on human health has sparked research on different approaches to measure, map, and predict heat exposure at more accurate and precise spatiotemporal scales. Personal heat sensor studies rely on small sensors that can continuously measure ambient temperatures as individuals move through time and space. The comparison between different types of sensors and sensor placements have yet to be fully researched. The objective of this study is to assess the validity of personal ambient temperature sensors. To accomplish this objective, we evaluated the performance of multiple low-cost wearable sensors (HOBOs, iButton Thermochrons, iButton Hygrochrons, and Kestrel DROP D3FW Fire) for measuring ambient temperature in a (1) field exposure study by varying the placement on human subjects and in a (2) field calibration study by co-locating sensors with fixed site weather station monitors. A secondary aim involved investigating consensus between validation metrics that can be used in future sensor comparison studies. Bland-Altman analysis, correlation coefficients, and index of agreement statistics were used to quantify the difference between sensor and weather station ambient temperature measurements. Results demonstrated significant differences in measured temperatures for sensors based on sensor type and placement on participants. Future research should account for the differences in personal ambient temperature readings based on sensor type and placement.

Evaluation of wearable sensors for physiologic monitoring of individually experienced temperatures in outdoor workers in southeastern U.S

Climate-related increases in global mean temperature and the intensification of heat waves present a significant threat to outdoor workers. Limited research has been completed to assess the potential differences in heat exposures that exist between individuals within similar microenvironments. Yet, there is a paucity of individual data characterizing patterns of individually experienced temperatures in workers and the associated physiologic heat strain response. The objective of this study was to apply a wearable sensor-based approach to examine the occupational, environmental, and behavioral factors that contribute to individual-level variations in heat strain in grounds maintenance workers. Outdoor workers from three diverse climatic locations in the southeastern United States - high temperature, high temperature + high humidity, and moderate temperature environments - participated in personal heat exposure monitoring during a 5-day work period in the summer. We performed Cox proportional hazards modeling to estimate associations between multiple heat strain events per worker and changes in individually experienced temperatures. Heat strain risk was higher among workers with a place to cool-off, higher education, and who worked in hotter temperatures. A mismatch was observed between workers' perceptions of heat strain and actual heat strain prevalence across exposure groups. We also used a quasi-Poisson regression with distributed lag non-linear function to estimate the non-linear and lag effects of individually experienced temperatures on risk of heat strain. The association between increasing temperature and heat strain was nonlinear and exhibited an U-shaped relationship. Heat strain was less common during issued heat warnings demonstrating behavioral adaptive actions taken by workers. This study is one of the first temperature monitoring studies to quantify the individual-level exposure-response function in this vulnerable population and highlights the elevated risk of heat strain both immediately and several days after worker exposure to high temperatures.

Estimating personal ambient temperature in moderately cold environments for occupationally exposed populations

Despite high mortality and morbidity rates in the winter season, few studies have investigated the health effects from working in moderately cold environments, especially among vulnerable outdoor worker populations in the southeastern US. Yet recent research has shown that the mortality risk from cold events is greatest in southern cities compared to other US locations. We performed repeated personal cold exposure measurements in outdoor grounds management workers in the southeastern US using consumer-based sensors. We recruited outdoor workers from two locations (Raleigh, NC and Boone, NC) each characterized by climatological differences in cold temperature to participate in a 3-week data collection period at the peak of the winter (Jan/Feb 2018). Lower personal ambient temperatures were observed among participants who worked in a warmer climate (Raleigh, NC). The relative risk for cold symptomatology was higher in moderately cold personal ambient temperatures (0 °C to 20 °C) than extremely cold personal ambient temperatures (less than 0 °C). A weak significant relationship was observed between personal ambient temperatures and weather station measurements highlighting that epidemiological researchers should be cautious when investigating the health effects of ambient temperatures based on fixed site measurements. As mobile technology progresses, real-time temperature health monitoring and analysis of environmental conditions at the individual level across multiple occupational-settings will become more feasible and ultimately, we believe, a digitally enhanced workforce will become standard practice in the field.

Critical care usage after major gastrointestinal and liver surgery: a prospective, multicentre observational study

BACKGROUND

Patient selection for critical care admission must balance patient safety with optimal resource allocation. This study aimed to determine the relationship between critical care admission, and postoperative mortality after abdominal surgery.

METHODS

This prespecified secondary analysis of a multicentre, prospective, observational study included consecutive patients enrolled in the DISCOVER study from UK and Republic of Ireland undergoing major gastrointestinal and liver surgery between October and December 2014. The primary outcome was 30-day mortality. Multivariate logistic regression was used to explore associations between critical care admission (planned and unplanned) and mortality, and inter-centre variation in critical care admission after emergency laparotomy.

RESULTS

Of 4529 patients included, 37.8% (n=1713) underwent planned critical care admissions from theatre. Some 3.1% (n=86/2816) admitted to ward-level care subsequently underwent unplanned critical care admission. Overall 30-day mortality was 2.9% (n=133/4519), and the risk-adjusted association between 30-day mortality and critical care admission was higher in unplanned [odds ratio (OR): 8.65, 95% confidence interval (CI): 3.51-19.97) than planned admissions (OR: 2.32, 95% CI: 1.43-3.85). Some 26.7% of patients (n=1210/4529) underwent emergency laparotomies. After adjustment, 49.3% (95% CI: 46.8-51.9%, P<0.001) were predicted to have planned critical care admissions, with 7% (n=10/145) of centres outside the 95% CI.

CONCLUSIONS

After risk adjustment, no 30-day survival benefit was identified for either planned or unplanned postoperative admissions to critical care within this cohort. This likely represents appropriate admission of the highest-risk patients. Planned admissions in selected, intermediate-risk patients may present a strategy to mitigate the risk of unplanned admission. Substantial inter-centre variation exists in planned critical care admissions after emergency laparotomies.

Thyroid gland volumes in premature infants using serial ultrasounds

BACKGROUND

There is a gap in knowledge about the postnatal growth of thyroid gland in preterm infants.

OBJECTIVE

To determine postnatal growth of thyroid gland in preterm infants.

METHODS

Thyroid gland volume was calculated in 57 prospectively enrolled preterm infants by measuring serial longitudinal, antero-posterior, and transverse dimensions of thyroid gland with ultrasound. Data were analyzed by using the Wilcoxon and independent t test.

RESULTS

There was a significant correlation between thyroid volume (TV) and birthweight (BW) (p = 0.01), and between TV and gestational age (p = 0.02). However, unexpectedly, 12 infants had a decrease in TV between the first and second ultrasounds. Infants with late onset bacterial sepsis had lower TVs on their second ultrasounds than infants without sepsis.

CONCLUSIONS

Thyroid ultrasound in preterm infants provides noninvasive and quick approach to determine TV and morphology. TV in preterm infants correlates positively with BW and gestational age. However, postnatal growth of thyroid gland is variable and may seemingly be affected by postnatal factors.

A Type 1 Diabetes Genetic Risk Score Predicts Progression of Islet Autoimmunity and Development of Type 1 Diabetes in Individuals at Risk

OBJECTIVE

We tested the ability of a type 1 diabetes (T1D) genetic risk score (GRS) to predict progression of islet autoimmunity and T1D in at-risk individuals.

RESEARCH DESIGN AND METHODS

We studied the 1,244 TrialNet Pathway to Prevention study participants (T1D patients' relatives without diabetes and with one or more positive autoantibodies) who were genotyped with Illumina ImmunoChip (median [range] age at initial autoantibody determination 11.1 years [1.2-51.8], 48% male, 80.5% non-Hispanic white, median follow-up 5.4 years). Of 291 participants with a single positive autoantibody at screening, 157 converted to multiple autoantibody positivity and 55 developed diabetes. Of 953 participants with multiple positive autoantibodies at screening, 419 developed diabetes. We calculated the T1D GRS from 30 T1D-associated single nucleotide polymorphisms. We used multivariable Cox regression models, time-dependent receiver operating characteristic curves, and area under the curve (AUC) measures to evaluate prognostic utility of T1D GRS, age, sex, Diabetes Prevention Trial-Type 1 (DPT-1) Risk Score, positive autoantibody number or type, HLA DR3/DR4-DQ8 status, and race/ethnicity. We used recursive partitioning analyses to identify cut points in continuous variables.

RESULTS

Higher T1D GRS significantly increased the rate of progression to T1D adjusting for DPT-1 Risk Score, age, number of positive autoantibodies, sex, and ethnicity (hazard ratio [HR] 1.29 for a 0.05 increase, 95% CI 1.06-1.6; P = 0.011). Progression to T1D was best predicted by a combined model with GRS, number of positive autoantibodies, DPT-1 Risk Score, and age (7-year time-integrated AUC = 0.79, 5-year AUC = 0.73). Higher GRS was significantly associated with increased progression rate from single to multiple positive autoantibodies after adjusting for age, autoantibody type, ethnicity, and sex (HR 2.27 for GRS >0.295, 95% CI 1.47-3.51; P = 0.0002).

CONCLUSIONS

The T1D GRS independently predicts progression to T1D and improves prediction along T1D stages in autoantibody-positive relatives.

Weight loss as a predictor of cancer and serious disease in primary care: an ISAC-approved CPRD protocol for a retrospective cohort study using routinely collected primary care data from the UK

BACKGROUND

Unexpected weight loss is a symptom of serious disease in primary care, for example between 1 in 200 and 1 in 30 patients with unexpected weight loss go on to develop cancer. However, it remains unclear how and when general practitioners (GPs) should investigate unexpected weight loss. Without clarification, GPs may wait too long before referring (choosing to watch and wait and potentially missing a diagnosis) or not long enough (overburdening hospital services and exposing patients to the risks of investigation). The overall aim of this study is to provide the evidence necessary to allow GPs to more effectively manage patients with unexpected weight loss.

METHODS

A retrospective cohort analysis of UK Clinical Practice Research Datalink (CPRD) data to: (1) describe how often in UK primary care the symptom of reported weight loss is coded, when weight is measured, and how GPs respond to a patient attending with unexpected weight loss; (2) identify the predictive value of recorded weight loss for cancer and serious disease in primary care, using cumulative incidence plots to compare outcomes between subgroups and Cox regression to explore and adjust for covariates. Preliminary work in CPRD estimates that weight loss as a symptom is recorded for approximately 148,000 eligible patients > 18 years and is distributed evenly across decades of age, providing adequate statistical power and precision in relation to cancer overall and common cancers individually. Further stratification by cancer stage will be attempted but may not be possible as not all practices within CPRD are eligible for cancer registry linkage, and staging information is often incomplete. The feasibility of using multiple imputation to address missing covariate values will be explored.

DISCUSSION

This will be the largest reported retrospective cohort of primary care patients with weight measurements and unexpected weight loss codes used to understand the association between weight measurement, unexpected weight loss, and serious disease including cancer. Our findings will directly inform international guidelines for the management of unexpected weight loss in primary care populations.

Diagnosis and management of upper extremity deep-vein thrombosis in adults

Upper extremity deep-vein thrombosis (UEDVT) is common and can cause important complications, including pulmonary embolism and post-thrombotic syndrome. An increase in the use of central venous catheters, particularly peripherally inserted central catheters has been associated with an increasing rate of disease. Accurate diagnosis is essential to guide management, but there are limitations to the available evidence for available diagnostic tests. Anticoagulation is the mainstay of therapy, but interventional treatments may be considered in select situations. The risk of UEDVT may be reduced by more careful selection of patients who receive central venous catheters and by use of smaller catheters. Herein we review the diagnosis, management and prevention of UEDVT. Due to paucity of research, some principles are drawn from studies of lower extremity DVT. We present a practical approach to diagnosing the patient with suspected deep-vein thrombosis of the upper extremity.

[The fiscal position of medical specialists]

Independent medical specialists in the Netherlands are treated as entrepreneurs for tax purposes and therefore enjoy tax benefits. A change in the legal relationship between medical specialists and hospitals is foreseen in 2015. Independent medical specialists will then no longer be considered to be entrepreneurs. This could negatively affect their tax position. The Dutch government has adopted a policy aimed at controlling expenses arising from medical specialists' fees. According to this policy, the formation of regional practices or mega-practices of specialists will be discouraged. In contrast, the current fiscal legislation encourages medical specialists to incorporate their practice into regional practices or mega-practices or to become shareholders of their hospitals. It has been proposed that fiscal benefits be linked to certain aspects of entrepreneurship, such as investing in medical equipment or employing medical personnel.