A pipeline for evaluation of machine learning/AI models to quantify PD-L1 immunohistochemistry

Immunohistochemistry (IHC) is used to guide treatment decisions in multiple cancer types. For treatment with checkpoint inhibitors, PD-L1 IHC is used as a companion diagnostic. However, the scoring of PD-L1 is complicated by its expression in cancer and immune cells. Separation of cancer and non-cancer regions is needed to calculate tumor proportion scores (TPS) of PD-L1, which is based on the percentage of PD-L1 positive cancer cells. Evaluation of PD-L1 expression requires highly experienced pathologists and is often challenging and time consuming. Here we used a multi-institutional cohort of 77 lung cancer cases stained centrally with the PD-L1 22C3 clone. We developed a four-step pipeline for measuring TPS that includes the co-registration of H&E, PD-L1 and negative control (NC) digital slides for exclusion of necrosis, segmentation of cancer regions and quantification of PD-L1+ cells. As cancer segmentation is a challenging step for TPS generation, we trained DeepLab V3 in the Visiopharm software package to outline cancer regions in PD-L1 and negative control (NC) images and evaluated the model performance by mean intersection over union (mIoU) against manual outlines. Only 14 cases were required to accomplish an mIoU of 0.82 for cancer segmentation in hematoxylin stained NC cases. For PD-L1 stained slides, a model trained on PD-L1 tiles augmented by registered NC tiles achieved an mIoU of 0.79. In segmented cancer regions from whole slide images, the digital TPS achieved an accuracy of 75% against the manual TPS scores from the pathology report. Major reasons for algorithmic inaccuracies include the inclusion of immune cells in cancer outlines and poor nuclear segmentation of cancer cells. Our transparent and stepwise approach and performance metrics can be applied to any IHC assay to provide pathologists with important insights when to apply and how to evaluate commercial automated IHC scoring systems.

Cost and Utilization Outcomes in Huntsman at Home, a Novel Oncology Hospital at Home Program

OBJECTIVES

In a real-world trial, we previously demonstrated that Huntsman at Home, a novel oncology hospital at home program, was associated with reduced health care utilization and costs. In this study, we sought to understand the impact of Huntsman at Home in specific patient subgroups defined by sex, age, area-level median income, Charlson Comorbidity Index, and current use of systemic anticancer therapy.

DESIGN

Retrospective case-control study of the Huntsman Cancer Institute. Electronic Data Warehouse of patients enrolled in Huntsman at Home between August 2018 through October 2019 vs usual-care patients.

SETTING AND PARTICIPANTS

A total of 169 patients admitted to Huntsman at Home compared with 198 usual-care patients.

METHODS

Five dichotomous subgroups evaluated including sex (female vs male), age (≥65 vs <65), income (≥$78,735 vs <$78,735), Charlson Comorbidity Index (≥2 vs <2), and current systemic anticancer therapy use vs no current systemic anticancer therapy. Groups were compared with patients receiving usual care. Primary outcomes included 30-day costs, hospital length of stay, unplanned hospitalizations, and emergency room visits.

RESULTS

Admission to Huntsman at Home was associated with an overall reduction across all 4 health care cost and utilization outcomes. Outcomes favoring admission to Huntsman at Home achieved statistical significance (P < .05) in at least 2 of the 4 outcomes for each subgroup studied. Of the subgroups that did not achieve statistically significant benefit from Huntsman at Home admission in some outcome categories, none of these subgroups favored usual care.

CONCLUSIONS AND IMPLICATIONS

Admission to Huntsman at Home decreased utilization of unplanned health care and reduced costs across a wide spectrum of patient subgroups, suggesting overall consistent benefit from the service. Hospital at home models should be considered as a means by which the quality and efficiency of care can be maximized for patients with cancer.

A Linguistic Analysis Examining the Impact of COVID-19 on Pneumonia Diagnosis and Disease Models

Written clinical language embodies and reflects the clinician's mental models of disease. Prior to the COVID-19 pandemic, pneumonia was shifting away from concern for healthcare-associated pneumonia and toward recognition of heterogeneity of pathogens and host response. How these models are reflected in clinical language or whether they were impacted by the pandemic has not been studied. We aimed to assess changes in the language used to describe pneumonia following the COVID-19 pandemic.

Low glycemic index noodle and pasta: Cereal type, ingredient, and processing

The consumption of noodles with a high glycemic index (GI) can affect health, prompting the need for dietary adjustments to manage abnormal blood glucose levels. This review delves into recent progress in low GI noodles and their potential effect for human well-being. Diverse approaches, encompassing the incorporation of soluble dietary fiber, modified starches, proteins, and plant polyphenols, have shown encouraging outcomes in diminishing the GI of noodles. Furthermore, variations in processing, storage, and cooking techniques can influence the GI of noodles, yielding both positive and negative impacts on their glycemic response. Soluble dietary fiber, protein cross-linkers, and plant polyphenols play a pivotal role in reducing the GI of noodles by hindering the interaction between digestive enzymes and starch, thereby curbing enzymatic activity. Future research spotlighting ingredients, processing methodologies, and the underlying mechanisms of low GI noodles will contribute substantively to the development of functional foods boosting enhanced nutritional profiles.

An exploration of the effect of Chinese herbal compound on the occurrence and development of large intestine cancer and intestinal flora

This study was conducted to observe the effect of Chinese herbal compound on the treatment of colon cancer using AOM/DSS-induced C57BL/6J colon cancer mice and to validate potential influence on intestinal flora of mice. A colorectal cancer (CRC) mouse model was built with a total of 50 C57BL/6J mice that were induced by administrating AOM/DSS. These experimental animals were split up into 5 groups, a control group, a model group, and low-, medium- and high-dose Chinese herbal compound groups. All mice were given Chinese herbal compound treatment, and the colon tissues of each group were harvested with the length measured and the number of colon polyps accounted. The Ki-67 expression in the colon tissues was detected via immuno-histochemistry. Relative quantification of the expression of genes and proteins was determined through qPCR and WB assays. Contents of IL-6, TNF-α, IFN-γ, and IL-10 in serum and colon tissues of mice were determined by ELISA. An additional 16S rRNA sequencing analysis was implemented for the identification of mouse intestinal flora. The results suggested that all low-, medium- or high-dose Chinese herbal compound could markedly inhibit the shortening of colon length and significant number reduction of colon polyps in the model group. The relative expression of genes and proteins (PCNA, Muc16, and MMP-9) associated with proliferation in mouse colon tissues were inhibited. In addition, compared with the model group, the contents of IL-6, TNF-α, and IFN-γ in serum and colon tissues were substantially decreased in the high-dose Chinese herbal compound group, thereby reducing the structure damage in colon tissues and the infiltration degree of inflammatory cells. Besides, the expression of TLR4/MyD88/NF-κB protein was markedly decreased. The 16S rRNA sequencing analysis demonstrated that mice in the model group had decreased intestinal flora diversity, and there were significant changes in flora abundance and amino acid metabolism between the control group and the model group. Taken together, the treatment of Chinese herbal compound against CRC in this study might be regulated by the TLR4/MyD88/NF-κB signaling pathway, and the imbalance in intestinal flora was also closely related to CRC occurrence.

Clinicopathological and prognostic significance of PD-L1 and TIM-3 expression in medullary thyroid carcinoma: a retrospective immunohistochemistry study

PURPOSE

Expression of the programmed death-ligand 1 (PD-L1) and T-cell immunoglobulin and mucin-domain containing-3 (TIM-3) in medullary thyroid carcinoma (MTC) has been controversial and rarely reported.

METHODS

Surgical specimens of 190 MTC patients who had initial curative-intent surgery were collected. Immunohistochemistry of PD-L1 and TIM-3 was performed using 22C3 pharmDx (Dako, Carpinteria, CA) and anti-TIM-3 (1:500, ab241332, Abcam). Stained slides were scored using a combined positive score (CPS) with a cutoff of ≥ 1. We established correlations between PD-L1 expression, TIM-3 expression, clinicopathological, and survival data.

RESULTS

13 cases (13/190, 6.84%) were positive for PD-L1 expression, and 42 cases (42/154, 27.27%) for TIM-3 expression. PD-L1 expression was correlated to TIM-3 expression (P = 0.002), but was not related to overall survival (OS) or progression-free survival (PFS). TIM-3 expression was correlated to perineural invasion (P = 0.040). Multivariate Cox analysis showed that lymphovascular invasion (LVI) was independently associated with OS. And tumor size, LVI, and lymph node metastases were significantly associated with PFS. Furthermore, the multivariate logistic analysis showed multifocal status, LVI, pathological T stage and lymph node metastasis were independent risk factors for biochemical recurrence/persistent disease.

CONCLUSIONS

We demonstrated that PD-L1 and TIM-3 expression were not frequent in MTC and were not associated with survival prognosis. Our results should be considered when clinical trials of PD-L1 or TIM-3 blockades are implemented.

Risk factors in ICU patients with initial acquisition of carbapenemase-resistant Klebsiella Pneumoniae

OBJECTIVE: To identify the risk factors associated with antimicrobial use on the initial acquisition of carbapenem-resistant Klebsiella pneumoniae (CRKP) in elderly intensive care unit (ICU) patients.METHODS: Respiratory secretion, blood, urine, anal swab and peritoneal drainage samples from all elderly patients with non-colonised CRKP who had been hospitalised from January 2021 to December 2022 were collected, and screened for CRKP colonisation using surveillance culture at the time of the first ICU admission and weekly thereafter in Zhejiang Provincial Hospital of Chinese Medicine, Zhejiang, China. Cumulative antibiotic variables included duration of antibiotic use, total amount of antimicrobials received in grams, total antibiotic consumption (defined daily dose) and the types of antimicrobial exposure. A time-dependent model based on Cox regression analysis was used to investigate the effect of each variable on the initial acquisition of CRKP infection or colonisation.RESULTS: Of 214 patients, 44 were infected or had CRKP colonies and death rate was 34.1%. males were the risk factor for acquiring CRKP in culture (HR 2.12, 95% CI 1.06-4.21; P = 0.033). It is notable that the hazard of acquiring CRKP increased by 9% with every single-point increase in the APACHE II score (HR 1.09, 95% CI 1.01-1.18; P = 0.025). The hazard of acquiring CRKP doubled when carbapenems were administered (HR 1.81, 95% CI 1.42-2.30; P < 0.001), In contrast, exposure to quinolone antimicrobials had a smaller effect on acquiring CRKP (HR 1.07; 95% CI 1.01-1.14; P = 0.024).CONCLUSION: This study found that male sex, APACHE II score and exposure to quinolones and carbapenems were independent risk factors for acquiring CRKP.

Efficacy and toxicity of midostaurin with idarubicin and cytarabine induction in <i>FLT3</I>-mutated acute myeloid leukemia

Not available.

Inter-fraction Dynamics during Adaptive Hypofractionated Radiotherapy for Brain Metastases with a MR LINAC

PURPOSE/OBJECTIVE(S)

This study examined the displacement and deformation in brain metastases (BMs) during adaptive hypofractionated radiotherapy (HFRT) on a magnetic resonance imaging linear accelerator (MR LINAC). In addition, the contouring variability between enhanced T1 (T1+c) and T2/FLAIR (T2f) sequence to define gross tumor volume (GTV) was compared.

MATERIALS/METHODS

Patients with 1-3 BMs and treated with MR LINAC were enrolled. T1+c sequence was acquired at initial planning, while T2/T2f was acquired during each fraction. GTV at initial planning (GTVi) and fraction 1-n (GTV1-n) were contoured in all images. Dice similarity coefficient (DSC) was used to quantify the contouring variability between different sequences at initial planning. The three-dimensional coordinate values of geometric centers of GTVi and GTV1-n were recorded and the distance was calculated. Statistical analysis was performed using two-sided paired t-test.

RESULTS

Between December 2019 and October 2022, 19 patients with 22 BMs were analyzed. The median age was 64 y (37-84 y) and the major primary tumor was lung cancer (89.5%). The median dose was 52 Gy in 13 fractions (30 Gy/5f- 60 Gy/20 f). The median GTVi on T1c, T2f and T2 sequences were 6.70cc (0.41-84.85 cc), 6.70 cc (0.35-84.14 cc, p = 0.924) and 6.16 cc (0.32-79.44 cc, p = 0.117), respectively. The mean DSC was 0.95 (0.76-1.00) and 0.86 (0.64-0.97) when comparing GTVi on T1c/T2f and T1c/T2, respectively. All of the lesions achieved volume reduction during HFRT and the mean reduction rate was 28.8% (4.8%-71.0%) at the end of HFRT. 54.5% of the BMs were reduced by more than 20%. The median treatment course and BED to get 20% reduction was 2/3 (40%-93%) and 40.8 Gy (24.5-67.5 Gy), respectively. The median shift of center of GTV1-n was 0.8 mm (0-2.5mm). The center of 7 lesions (31.8%) deviated more than 1mm from GTVi.

CONCLUSION

GTV contouring variability was seen between T1c, T2f and T2 sequences. The coincidence of T1+c and T2f was better than T1+c and T2 in BMs. Since reductions in volume and changes of lesion center was observed during HFRT, the use of MR-guided radiation therapy (RT) and treatment adaptation is needed. The optimal timing for treatment plan modification might be when the course of treatment reaches 2/3 for most large BMs. Further research to find out patients who may benefit form MR-guided adaptive RT is ongoing.

Estimated Population Health Benefits of Intensive Systolic Blood Pressure Treatment Among SPRINT-Eligible US Adults

BACKGROUND

The Systolic Blood Pressure Intervention Trial (SPRINT) demonstrated an intensive (<120 mm Hg) vs. standard (<140 mm Hg) systolic blood pressure (SBP) goal lowered cardiovascular disease (CVD) risk. Estimating the effect of intensive SBP lowering among SPRINT-eligible adults most likely to benefit can guide implementation efforts.

METHODS

We studied SPRINT participants and SPRINT-eligible participants in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) Study and National Health and Nutrition Examination Surveys (NHANES). A published algorithm of predicted CVD benefit with intensive SBP treatment was used to categorize participants into low, medium, or high predicted benefit. CVD event rates were estimated with intensive and standard treatment.

RESULTS

Median age was 67.0, 72.0, and 64.0 years in SPRINT, SPRINT-eligible REGARDS, and SPRINT-eligible NHANES participants, respectively. The proportion with high predicted benefit was 33.0% in SPRINT, 39.0% in SPRINT-eligible REGARDS, and 23.5% in SPRINT-eligible NHANES. The estimated difference in CVD event rate (standard minus intensive) was 7.0 (95% confidence interval [CI] 3.4-10.7), 8.4 (95% CI 8.2-8.5), and 6.1 (95% CI 5.9-6.3) per 1,000 person-years in SPRINT, SPRINT-eligible REGARDS participants, and SPRINT-eligible NHANES participants, respectively (median 3.2-year follow-up). Intensive SBP treatment could prevent 84,300 (95% CI 80,800-87,920) CVD events per year in 14.1 million SPRINT-eligible US adults; 29,400 and 28,600 would be in 7.0 million individuals with medium or high predicted benefit, respectively.

CONCLUSIONS

Most of the population health benefit from intensive SBP goals could be achieved by treating those characterized by a previously published algorithm as having medium or high predicted benefit.

Incidence and Outcomes of Non-Ventilator-Associated Hospital-Acquired Pneumonia in 284 US Hospitals Using Electronic Surveillance Criteria

Importance

Non-ventilator-associated hospital-acquired pneumonia (NV-HAP) is a common and deadly hospital-acquired infection. However, inconsistent surveillance methods and unclear estimates of attributable mortality challenge prevention.

Objective

To estimate the incidence, variability, outcomes, and population attributable mortality of NV-HAP.

Design, Setting, and Participants

This cohort study retrospectively applied clinical surveillance criteria for NV-HAP to electronic health record data from 284 US hospitals. Adult patients admitted to the Veterans Health Administration hospital from 2015 to 2020 and HCA Healthcare hospitals from 2018 to 2020 were included. The medical records of 250 patients who met the surveillance criteria were reviewed for accuracy.

Exposures

NV-HAP, defined as sustained deterioration in oxygenation for 2 or more days in a patient who was not ventilated concurrent with abnormal temperature or white blood cell count, performance of chest imaging, and 3 or more days of new antibiotics.

Main Outcomes and Measures

NV-HAP incidence, length-of-stay, and crude inpatient mortality. Attributable inpatient mortality by 60 days follow-up was estimated using inverse probability weighting, accounting for both baseline and time-varying confounding.

Results

Among 6 022 185 hospitalizations (median [IQR] age, 66 [54-75] years; 1 829 475 [26.1%] female), there were 32 797 NV-HAP events (0.55 per 100 admissions [95% CI, 0.54-0.55] per 100 admissions and 0.96 per 1000 patient-days [95% CI, 0.95-0.97] per 1000 patient-days). Patients with NV-HAP had multiple comorbidities (median [IQR], 6 [4-7]), including congestive heart failure (9680 [29.5%]), neurologic conditions (8255 [25.2%]), chronic lung disease (6439 [19.6%]), and cancer (5,467 [16.7%]); 24 568 cases (74.9%) occurred outside intensive care units. Crude inpatient mortality was 22.4% (7361 of 32 797) for NV-HAP vs 1.9% (115 530 of 6 022 185) for all hospitalizations; 12 449 (8.0%) were discharged to hospice. Median [IQR] length-of-stay was 16 (11-26) days vs 4 (3-6) days. On medical record review, pneumonia was confirmed by reviewers or bedside clinicians in 202 of 250 patients (81%). It was estimated that NV-HAP accounted for 7.3% (95% CI, 7.1%-7.5%) of all hospital deaths (total hospital population inpatient death risk of 1.87% with NV-HAP events included vs 1.73% with NV-HAP events excluded; risk ratio, 0.927; 95% CI, 0.925-0.929).

Conclusions and Relevance

In this cohort study, NV-HAP, which was defined using electronic surveillance criteria, was present in approximately 1 in 200 hospitalizations, of whom 1 in 5 died in the hospital. NV-HAP may account for up to 7% of all hospital deaths. These findings underscore the need to systematically monitor NV-HAP, define best practices for prevention, and track their impact.

Implementation and outcomes of a clinician-directed intervention to improve antibiotic prescribing for acute respiratory tract infections within the Veterans' Affairs Healthcare System

OBJECTIVE

To determine whether a clinician-directed acute respiratory tract infection (ARI) intervention was associated with improved antibiotic prescribing and patient outcomes across a large US healthcare system.

DESIGN

Multicenter retrospective quasi-experimental analysis of outpatient visits with a diagnosis of uncomplicated ARI over a 7-year period.

PARTICIPANTS

Outpatients with ARI diagnoses: sinusitis, pharyngitis, bronchitis, and unspecified upper respiratory tract infection (URI-NOS). Outpatients with concurrent infection or select comorbid conditions were excluded.

INTERVENTION(S)

Audit and feedback with peer comparison of antibiotic prescribing rates and academic detailing of clinicians with frequent ARI visits. Antimicrobial stewards and academic detailing personnel delivered the intervention; facility and clinician participation were voluntary.

MEASURE(S)

We calculated the probability to receive antibiotics for an ARI before and after implementation. Secondary outcomes included probability for a return clinic visits or infection-related hospitalization, before and after implementation. Intervention effects were assessed with logistic generalized estimating equation models. Facility participation was tracked, and results were stratified by quartile of facility intervention intensity.

RESULTS

We reviewed 1,003,509 and 323,023 uncomplicated ARI visits before and after the implementation of the intervention, respectively. The probability to receive antibiotics for ARI decreased after implementation (odds ratio [OR], 0.82; 95% confidence interval [CI], 0.78-0.86). Facilities with the highest quartile of intervention intensity demonstrated larger reductions in antibiotic prescribing (OR, 0.69; 95% CI, 0.59-0.80) compared to nonparticipating facilities (OR, 0.89; 95% CI, 0.73-1.09). Return visits (OR, 1.00; 95% CI, 0.94-1.07) and infection-related hospitalizations (OR, 1.21; 95% CI, 0.92-1.59) were not different before and after implementation within facilities that performed intensive implementation.

CONCLUSIONS

Implementation of a nationwide ARI management intervention (ie, audit and feedback with academic detailing) was associated with improved ARI management in an intervention intensity-dependent manner. No impact on ARI-related clinical outcomes was observed.

Identifying Patients for Intensive Blood Pressure Treatment Based on Cognitive Benefit: A Secondary Analysis of the SPRINT Randomized Clinical Trial

Importance

Intensive vs standard treatment to lower systolic blood pressure (SBP) reduces risk of mild cognitive impairment (MCI) or dementia; however, the magnitude of cognitive benefit likely varies among patients.

Objective

To estimate the magnitude of cognitive benefit of intensive vs standard systolic BP (SBP) treatment.

Design, Setting, and Participants

In this ad hoc secondary analysis of the Systolic Blood Pressure Intervention Trial (SPRINT), 9361 randomized clinical trial participants 50 years or older with high cardiovascular risk but without a history of diabetes, stroke, or dementia were followed up. The SPRINT trial was conducted between November 1, 2010, and August 31, 2016, and the present analysis was completed on October 31, 2022.

Intervention

Systolic blood pressure treatment to an intensive (<120 mm Hg) vs standard (<140 mm Hg) target.

Main Outcomes and Measures

The primary outcome was a composite of adjudicated probable dementia or amnestic MCI.

Results

A total of 7918 SPRINT participants were included in the analysis; 3989 were in the intensive treatment group (mean [SD] age, 67.9 [9.2] years; 2570 [64.4%] men; 1212 [30.4%] non-Hispanic Black) and 3929 were in the standard treatment group (mean [SD] age, 67.9 [9.4] years; 2570 [65.4%] men; 1249 [31.8%] non-Hispanic Black). Over a median follow-up of 4.13 (IQR, 3.50-5.88) years, there were 765 and 828 primary outcome events in the intensive treatment group and standard treatment group, respectively. Older age (hazard ratio [HR] per 1 SD, 1.87 [95% CI, 1.78-1.96]), Medicare enrollment (HR per 1 SD, 1.42 [95% CI, 1.35-1.49]), and higher baseline serum creatinine level (HR per 1 SD, 1.24 [95% CI, 1.19-1.29]) were associated with higher risk of the primary outcome, while better baseline cognitive functioning (HR per 1 SD, 0.43 [95% CI, 0.41-0.44]) and active employment status (HR per 1 SD, 0.44 [95% CI, 0.42-0.46]) were associated with lower risk of the primary outcome. Risk of the primary outcome by treatment goal was estimated accurately based on similar projected and observed absolute risk differences (C statistic = 0.79). Higher baseline risk for the primary outcome was associated with greater benefit (ie, larger absolute reduction of probable dementia or amnestic MCI) of intensive vs standard treatment across the full range of estimated baseline risk.

Conclusions and Relevance

In this secondary analysis of the SPRINT trial, participants with higher baseline projected risk of probable dementia or amnestic MCI gained greater absolute cognitive benefit from intensive vs standard SBP treatment in a monotonic fashion.

Trial Registration

ClinicalTrials.gov Identifier: NCT01206062.

A Real-World Comparison of Regorafenib and Trifluridine/Tipiracil in Refractory Metastatic Colorectal Cancer in the United States

BACKGROUND

Trifluridine/Tipiracil (TAS-102) and regorafenib are FDA-approved in the United States for treatment of refractory metastatic colorectal cancer (mCRC). FDA approvals of these agents were based on modest improvements in overall survival (OS) compared with best supportive care + placebo in the RECOURSE and CORRECT trials, respectively. This study compared real-world clinical outcomes with the use of these agents.

METHODS

A nationwide deidentified electronic health record-derived database was reviewed for patients diagnosed with mCRC between 2015 and 2020. Patients who received at least 2 lines of standard systemic therapy followed by treatment with either TAS-102 or regorafenib were included for analysis. Kaplan-Meier and propensity score-weighted proportional hazards models were used to compare survival outcomes between groups.

RESULTS

The records of 22,078 patients with mCRC were reviewed. Of these, 1,937 patients received at least 2 lines of standard therapy followed by regorafenib and/or TAS-102. Median OS for the TAS-102 alone or prior regorafenib group (n=1,016) was 6.66 months (95% CI, 6.16-7.18 months) compared with 6.30 months (95% CI, 5.80-6.79 months) for regorafenib alone or prior to TAS-102 (n=921; P=.36). A propensity score-weighted analysis controlling for potential confounders did not demonstrate a significant difference in survival between groups (hazard ratio, 0.99; 95% CI, 0.90-1.09; P=.82). A subgroup analysis did not identify any significant differences in outcomes regarding age, performance status, tumor sidedness, microsatellite instability status, or RAS/RAF status.

CONCLUSIONS

This analysis of real-world data found that OS was similar for patients with mCRC who were treated with TAS-102 compared with regorafenib. Median OS with both agents in a real-world setting was similar to that shown in the clinical trials that led to their approvals. A prospective trial comparing TAS-102 and regorafenib would unlikely change current management of patients with refractory mCRC.

Predicting IHC staining classes of NF1 using features in the hematoxylin channel

Immunohistochemistry (IHC) highlights specific cell types in tissues and traditionally involves antibody staining together with a hematoxylin counterstain. The intensity and pattern of hematoxylin staining differs between cell types and reveals morphological characteristics of cells. Here, we propose that features in the hematoxylin stain can be used to predict IHC labels, such as Neurofibromin (encoded by the gene NF1). The dataset consists of 7.2 million cells from benign and kidney cancer cores in a tissue microarray. Morphology and hematoxylin (H&M) features defined within QuPath are subjected to a clustering analysis in CytoMap. H&M features are also used to train 4 different XGBoost models to predict high, low, and negative NF1 stain classes in benign renal tubules, clear cell (ccRCC), papillary (PRCC), and chromophobe (ChRCC) renal carcinoma. The prediction accuracies of NF1 staining classes in benign, ccRCC, ChRCC, and PRCC range between 70% and 90% with areas under the precision recall curve PRAUC_NF1-high = 0.82+0.12, PRAUC_NF1-low = 0.62+0.25, and PRAUC_NF1-negative = 0.83+0.16. The most important feature for predicting the NF1 class involves the minimum cellular hematoxylin staining intensity. Together, these results demonstrate the feasibility to predict NF1 expression solely from features in hematoxylin staining using open source software. Since the hematoxylin features can be obtained from regular H&E and IHC slides, the proposed workflow has broad applicability.

A comparison between partially peeled hulless barley and whole grain hulless barley: beneficial effects on the regulation of serum glucose and the gut microbiota in high-fat diet-induced obese mice

Though the hypoglycemic effect of whole grain hulless barley (Hordeum vulgare L.) has been documented, whether glucose metabolism would be improved by hulless barley with moderate peeling is still unclear. The purpose of this study was to compare the differences in glucose metabolism and gut microbiota between partially (10%) peeled hulless barley (PHB) and whole grain hulless barley (WHB) intervention in obese mice induced by a high-fat diet. The results showed that both PHB and WHB interventions significantly improved the impaired glucose tolerance, fat accumulation in fat and liver tissues, and the impaired intestinal barrier in mice. The dysbiosis of gut microbiota was improved and the relative abundance of some beneficial bacteria such as genera Lactobacillus, Bifidobacterium, Ileibacterium, and norank_f__Mutibaculaceae was increased by both, PHB and WHB, interventions. Spearman correlation analysis revealed that the abundance of Bifidobacterium was negatively correlated with the area under the blood glucose curve. In conclusion, our results provide evidence that hulless barley improved the gut microbiota and impaired glucose tolerance in mice, and also showed that there was little loss of hypoglycemic effect even when hulless barley was moderately peeled.

Hospital Admission Decisions for Older Veterans with Community-onset Pneumonia: An Analysis of 118 U.S. Veterans Affairs Medical Centers

OBJECTIVES

Age is important for prognosis in community-onset pneumonia, but how it influences admission decisions in the emergency department (ED) is not well characterized. Using clinical data from the electronic health record in a national cohort, we examined pneumonia hospitalization patterns, variation, and relationships with mortality among older versus younger Veterans.

METHODS

In a retrospective cohort of patients ≥18 years presenting to EDs with a diagnosis of pneumonia at 118 VA Medical Centers 1/1/2006-12/31/2016, we compared observed, predicted, and residual hospitalization risk for Veterans < 70,70-79, ≥ 80 years of age using generalized estimating equations and machine learning models with 71 patient factors. We examined facility variation in residual hospitalization across facilities and explored whether facility differences in hospitalization risk correlated with differences in 30-day mortality.

RESULTS

Among 297,498 encounters, 165,003(55%) were for Veterans <70 years, 61,076(21%) 70-80, and 71,419(24%) >=80. Hospitalization rate was 52%, 67%, and 76%, respectively. After adjusting for other patient factors, age 70-79 had an odds ratio of 1.39(1.34,1.44) and ≥80 had an odds ratio of 2.1(2.0,2.2) compared to age <70. There was substantial variation in hospitalization across facilities among Veterans <70 (<35% hospitalization at the lowest decile of facilities versus >66% at the highest decile) that was similar but with higher risk for patients 70-79 years (54% versus 82%) and ≥80 years (59% versus 85%) and remained after accounting for patient factors, with no consistently positive or negative associations with facility-level 30-day mortality.

CONCLUSIONS

Older Veterans with community-onset pneumonia experience high risk of hospitalization, with widespread facility variation that has no clear relationship to short-term mortality.

IMPACT STATEMENT

Older Veterans with pneumonia have a high risk of hospitalization, with widespread facility-level variation with no clear relationship with mortality. These findings illustrate a need to further examine the benefits and harms of hospitalization for older adults.

[Efficacy of sacubitril/valsartan in peritoneal dialysis patients with HFpEF and its effect on residual renal function]

Objective: To investigate the efficacy of sacubitril/valsartan in peritoneal dialysis (PD) patients with heart failure with preserved ejection fraction (HFpEF) and its effect on residual renal function. Methods: PD patients with HFpEF in Ningbo First Hospital from March 2018 to August 2021 were retrospectively enrolled and divided into study group with sacubitril/valsartan and control group with valsartan. The clinical baseline data before treatment and clinical indicators during follow-up (6 and 12 months after treatment) were collected and compared between the two groups, and the adverse reactions were also recorded. Results: A total of 99 patients were included in the study. There were 61 patients in the study group, including 44 males and 17 females, with a mean age of (52±13) years. Meanwhile, there were 38 patients in the control group, including 23 males and 15 females, with a mean age of (57±14) years. There was no statistically significant difference in clinical baseline data between the two groups (e.g., age, sex, body mass index, duration of dialysis) (all P>0.05). The N-terminal pro-B-type natriuretic peptide (NT-proBNP) and left ventricular end-systolic dimension (LVDs) were lower, but the left ventricular ejection fraction (LVEF) was higher in the study group than those in the control group at 6 and 12 months after treatment (all P<0.05). The systolic blood pressure (SBP) and diastolic blood pressure (DBP) of the two groups were lower than baseline values at 6 and 12 months after treatment respectively, with statistically significant differences (all P<0.05). However, there were no statistically significant differences in the decreases of SBP and DBP between the two groups at 6 and 12 months after treatment (all P>0.05). The decrease extents in residual estimated glomerular filtration rate (eGFR) [0.52 (-0.05, 1.19) vs 1.72 (0.97, 2.39) ml·min^-1·(1.73 m²)^-1, P<0.001]and 24-h residual urine volume [200 (-100, 300) vs 300 (137, 400) ml, P=0.018] at 12 months after treatment were lower in the study group than those in the control group. During the follow-up period, hyperkalemia occurred in 16 cases (26.2%) and 13 cases (34.2%) in the study group and the control group, and hypotension occurred in 3 cases (4.9%) and 1 case (2.6%) in the study group and the control group, respectively. There were no adverse reactions such as cough and angioneurotic edema in the two groups. Conclusions: Sacubitril/valsartan can safely and effectively improve cardiac function and lower blood pressure in PD patients with HFpEF. Compared with valsartan, sacubitril/valsartan may be more beneficial to delay the loss of residual renal function in PD patients with HFpEF.

Development and evaluation of an interoperable natural language processing system for identifying pneumonia across clinical settings of care and institutions

Objective

To evaluate the feasibility, accuracy, and interoperability of a natural language processing (NLP) system that extracts diagnostic assertions of pneumonia in different clinical notes and institutions.

Materials and Methods

A rule-based NLP system was designed to identify assertions of pneumonia in 3 types of clinical notes from electronic health records (EHRs): emergency department notes, radiology reports, and discharge summaries. The lexicon and classification logic were tailored for each note type. The system was first developed and evaluated using annotated notes from the Department of Veterans Affairs (VA). Interoperability was assessed using data from the University of Utah (UU).

Results

The NLP system was comprised of 782 rules and achieved moderate-to-high performance in all 3 note types in VA (precision/recall/f1: emergency = 88.1/86.0/87.1; radiology = 71.4/96.2/82.0; discharge = 88.3/93.0/90.1). When applied to UU data, performance was maintained in emergency and radiology but decreased in discharge summaries (emergency = 84.7/94.3/89.3; radiology = 79.7/100.0/87.9; discharge = 65.5/92.7/76.8). Customization with 34 additional rules increased performance for all note types (emergency = 89.3/94.3/91.7; radiology = 87.0/100.0/93.1; discharge = 75.0/95.1/83.4).

Conclusion

NLP can be used to accurately identify the diagnosis of pneumonia across different clinical settings and institutions. A limited amount of customization to account for differences in lexicon, clinical definition of pneumonia, and EHR structure can achieve high accuracy without substantial modification.

Trends in Illness Severity, Hospitalization, and Mortality for Community-Onset Pneumonia at 118 US Veterans Affairs Medical Centers

BACKGROUND

Deaths from pneumonia were decreasing globally prior to the COVID-19 pandemic, but it is unclear whether this was due to changes in patient populations, illness severity, diagnosis, hospitalization thresholds, or treatment. Using clinical data from the electronic health record among a national cohort of patients initially diagnosed with pneumonia, we examined temporal trends in severity of illness, hospitalization, and short- and long-term deaths.

DESIGN

Retrospective cohort PARTICIPANTS: All patients >18 years presenting to emergency departments (EDs) at 118 VA Medical Centers between 1/1/2006 and 12/31/2016 with an initial clinical diagnosis of pneumonia and confirmed by chest imaging report.

EXPOSURES

Year of encounter.

MAIN MEASURES

Hospitalization and 30-day and 90-day mortality. Illness severity was defined as the probability of each outcome predicted by machine learning predictive models using age, sex, comorbidities, vital signs, and laboratory data from encounters during years 2006-2007, and similar models trained on encounters from years 2015 to 2016. We estimated the changes in hospitalizations and 30-day and 90-day mortality between the first and the last 2 years of the study period accounted for by illness severity using time covariate decompositions with model estimates.

RESULTS

Among 196,899 encounters across the study period, hospitalization decreased from 71 to 63%, 30-day mortality 10 to 7%, 90-day mortality 16 to 12%, and 1-year mortality 29 to 24%. Comorbidity risk increased, but illness severity decreased. Decreases in illness severity accounted for 21-31% of the decrease in hospitalizations, and 45-47%, 32-24%, and 17-19% of the decrease in 30-day, 90-day, and 1-year mortality. Findings were similar among underrepresented patients and those with only hospital discharge diagnosis codes.

CONCLUSIONS

Outcomes for community-onset pneumonia have improved across the VA healthcare system after accounting for illness severity, despite an increase in cases and comorbidity burden.

Treatment outcomes in recurrent versus de novo metastatic pancreatic adenocarcinoma: a real world study

Background

A majority of patients undergoing curative intent surgery for pancreatic ductal adenocarcinoma (PDAC) will unfortunately develop recurrent disease. Treatment outcomes for patients with metastatic disease remain suboptimal. In this study, we evaluated clinical outcomes of patients with recurrent PDAC who received systemic therapy and compared outcomes to patients with de novo metastatic PDAC undergoing systemic therapy.

Methods

Patients diagnosed with metastatic PDAC between 2014 and 2019 were included using a real-world database. Patients were characterized as either de novo or recurrent based on the date of metastatic diagnosis and history of surgical resection. Overall survival (OS) was summarized within groups via Kaplan–Meier survival estimates and compared using Cox proportional hazards models.

Results

We included 5170 patients with metastatic PDAC, of which 1101 (21.3%) were classified as having recurrent disease. Median OS for the recurrent group was significantly greater at 10.8 m (95% CI 9.9–11.7) than in the de novo group at 7.3 m (95% CI 7.0–7.7, p < 0.001). We did not observe a significant difference in OS based on when patients recurred after surgery: 10.0 m (95% CI 8.7–11) within six months of surgery versus 11.6 m (95% CI 10–12, p = 0.256) greater than six months from surgery.

Conclusions

These data support the inclusion of patients with recurrent PDAC in clinical trials for advanced disease, including those who develop recurrent disease within six months of surgery. Due to observed differences in survival, randomization should be stratified by disease presentation (recurrent vs de novo).

Exploring cost and utilization outcomes of Huntsman at Home: Which patients benefit most from a novel oncology hospital at home program?

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Background: We previously demonstrated that Huntsman at Home (HH), a novel oncology hospital at home program, was associated with reduced healthcare utilization and costs. HH was also linked to shorter hospital stays and fewer emergency room (ER) visits. In this study, we sought to understand the impact of HH in specific patient subgroups. Methods: We compared outcomes among 169 patients consecutively admitted to HH against 198 usual care patients. Five dichotomous subgroups were created based upon patient a) sex b) age c) area level median income d) Charlson Comorbidity Index (CCI), and e) current use of systemic therapy (ST). Outcomes included 30-day costs, unplanned hospitalizations (UH), length of hospital stays, and ER visits. HH and usual care were compared via inverse propensity weighted regression models. Treatment propensities were estimated via random forests based on age, race, stage, cancer site, presence of metastases, CCI, and area level median income.Results: The between group difference favoring HH achieved statistical significance (p < 0.05) for at least two out of the four outcomes in each subgroup except for patients with higher comorbid illnesses. While HH participants did not always experience statistically better outcomes than usual care, none of the outcomes examined favored usual care for any subgroup. Sex. Female and male HH patients experienced fewer UH and lower costs than usual care. Male HH patients also had shorter hospital stays and fewer ED visits. Age. When stratifying age at 65 years, older HH patients experienced fewer days in the hospital and fewer UH. Younger HH patients had lower costs, and fewer UH and ED visits. Area level Income. All outcomes were better for high and low income HH patients compared to usual care except for ED visits among those with low income. CCI. Among those with a low CCI score, all four outcomes were better among HH patients. In contrast, differences between groups with higher comorbid illness did not achieve statistical significance for any outcome. Systemic Therapy. HH participants on ST experienced shorter hospital stays and fewer UH compared to usual care. Among those not on ST, HH patients experienced lower costs, and fewer UH and ED admissions. Conclusions: In this exploratory analysis, we found that the utilization and cost benefit associated with HH was robust, favoring better outcomes in each subgroup including lower 30-day costs, shorter hospital length of stay and fewer unplanned hospitalizations or ER visits. While medically complex patients may not receive similar benefit from HH as other subgroups, no outcomes favored patients managed by usual care. Taken together, this suggests that health care utilization and cost reductions associated with HH occur across multiple subgroups, but patients with high comorbidity may require additional intervention to realize lower utilization and costs.

Impact of wheat bran micronization on dough properties and bread quality: Part II - Quality, antioxidant and nutritional properties of bread

To investigate the impact of superfine grinding of wheat bran on bread quality, antioxidant and nutritional properties, bran with different particle sizes (coarse, D₅₀ of 362.3 μm; medium, 60.4 μm; superfine, 11.3 μm) were produced and fortified to white bread at three levels (10, 20 and 30%). At 20% fortification, compared to coarse bran, superfine bran increased the hardness and reduced the brightness of bread crumb by 56.3 and 3.30%, respectively, while it decreased bread's cell size by 10.7% and insignificantly impacted on bread's specific volume and porosity. Superfine bran retarded bread staling by 8.3% than coarse bran. It resulted in significantly better sensory attributes of bread in taste, texture and general palatability, and the fortified bread was overall acceptable (score > 6). Moreover, faster release of antioxidants (285-353% higher k), slower release of glucose (10.8% lower k), 3.76% less rapidly digestible starch, 5.65% more slowly digestible starch and 13.2% more resistant starch were found in the superfine group than the coarse one. Results demonstrated the potential of 20% fortification of superfine bran in developing fibre-enriched bread with satisfactory quality, increased antioxidant property and improved glycaemic modulation.

Computerized Cognitive Training in Amnestic Mild Cognitive Impairment: A Randomized Clinical Trial

OBJECTIVE

Computerized cognitive training has been successful in healthy older adults, but its efficacy has been mixed in patients with amnestic Mild Cognitive Impairment (MCI).

METHODS

In a randomized, placebo-controlled, double-blind, parallel clinical trial, we examined the short- and long-term efficacy of a brain-plasticity computerized cognitive training in 113 participants with amnestic MCI.

RESULTS

Immediately after 40-hours of training, participants in the active control group who played computer games performed better than those in the experimental group on the primary cognitive outcome (p = 0.02), which was an auditory memory/attention composite score. There were no group differences on 2 secondary outcomes (global cognitive composite and rating of daily functioning). After 1 year, there was no difference between the 2 groups on primary or secondary outcomes. No adverse events were noted.

CONCLUSIONS

Although the experimental cognitive training program did not improve outcomes in those with MCI, the short-term effects of the control group should not be dismissed, which may alter treatment recommendations for these patients.

Ethnicity impact on oral processing behaviour and glycemic response to noodles: Chinese (Asian) vs. New Zealander (Caucasian)

There is an increasing awareness of the link between food breakdown during chewing and its nutrient release and absorption in the gastrointestinal tract. However, how oral processing behaviour varies among different ethnic groups, and how such difference further impacts on bolus characteristics and consequently glycemic response (GR) are not well understood. In this study, we recruited a group of Asian (Chinese) subjects in China (n = 32) and a group of Caucasian subjects in New Zealand (n = 30), both aged between 18 and 30 years, and compared their blood glucose level (BGL) over 120 min following consumption of a glucose drink and cooked white noodles. We also assessed their chewing behaviour, unstimulated saliva flow rate, and ready-to-swallow bolus characteristics to determine whether these measures explain the ethnic differences in postprandial glycaemia. Compared to New Zealand subjects, the Chinese subjects showed 35% slower saliva flow rate but around 2 times higher salivary α-amylase activity in the unstimulated state. During consumption of noodles, Chinese subjects on average took a larger mouthful size, chewed each mouthful for longer and swallowed a larger number of particles with a smaller particle size area. Total GR measured by area under the curve (IAUC) was higher among the Chinese subjects. They also experienced higher BGL at 15 min, as well as higher peak BGL. There were strong correlations observed between oral processing and GR parameters. Results of this study confirmed the significance of oral processing in determining food digestion, and will provide new insights on the role of ethnicity in influencing people's physiological response to food.

A real-world comparison of trifluridine/tipiracil and regorafenib in refractory metastatic colorectal cancer in the United States

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Background: For patients with refractory metastatic colorectal cancer (mCRC), both trifluridine/tipiracil (TAS-102) and regorafenib have received approval for use in the United States. The approvals of these agents were based on modest improvements in overall survival (OS) when compared to best supportive care plus a placebo in the RECOURSE and CORRECT trials, respectively. However, TAS-102 and regorafenib have never been directly compared in a prospective clinical trial. This study utilized a large real-world database to compare clinical outcomes with use of these agents. Methods: The nationwide de-identified Flatiron Health EHR-derived database was reviewed for patients diagnosed with mCRC between 2015 and 2020. Patients who received at least two lines of guideline recommended therapy for advanced disease followed by treatment with TAS-102 and/or regorafenib in the third line or greater were included for analysis. Patients who did not have a visit or medication order within 90 days of metastatic diagnosis were excluded to ensure patients were engaged with care at the data-providing institution. Kaplan-Meier and propensity score weighted models were used to compare survival outcomes between groups. Results: The records of 22,078 patients with mCRC were reviewed. Of the 4,407 patients that received at least two lines of standard therapy, 2,072 subsequently received regorafenib and/or TAS-102. Of these, 813 (39.2%) received TAS-102 alone, 275 (13.3%) TAS-102 followed by regorafenib, 736 (35.5%) regorafenib alone, and 248 (12.0%) regorafenib followed by TAS-102. Median OS for patients treated with TAS-102 alone or prior to receiving regorafenib was 6.66 months (95% CI 6.16-7.18) compared to 6.30 months (95% CI 5.80-6.79) for those treated with regorafenib alone or prior to receiving TAS-102 (p = 0.36). A propensity score weighted analysis controlling for age, race, stage at initial diagnosis, performance status at start of therapy, MSI/MMR status, RAS/RAF status, and line in which TAS-102 or regorafenib was received did not demonstrate a significant difference in survival between groups (HR 0.99, 95% CI: 0.90 -1.09, p = 0.82). A subgroup analysis did not identify any significant differences in outcomes stratified by age, performance status, MSI status, or RAS/RAF status. Conclusions: This analysis of real-world data did not identify a significant difference in survival outcomes in mCRC patients who were treated with TAS-102 or regorafenib. Median OS with both agents in a real-world setting was similar to that shown in the clinical trials that led to their approvals. This data should be considered when discussing the risks and benefits of TAS-102 and regorafenib with mCRC patients who are eligible for third line or greater treatment.

1310. Provider and Facility Variation in Empiric Broad-Spectrum Antibiotic Use for Hospitalization Pneumonia: A Mixed Methods Study of Veterans Affairs Facilities

Background

We previously found widespread variation in the empiric use of antibiotics against methicillin-resistant Staph aureus (anti-MRSA) and Pseudomonas aeruginosa (anti-PAER) for patients hospitalized for pneumonia. To explore this variation further, we conducted (1) quantitative analyses of facility-level versus provider-level variation, and (2) qualitative interviews with emergency department providers.

Methods

For each hospitalization, we predicted the probability of anti-MRSA and anti-PAER use by fitting machine learning models from 75 patient variables. We estimated the predicted risk of anti-MRSA/anti-PAER and facility features among patients hospitalized at upper versus lower 10% facilities after controlling for patient characteristics. We plotted density curves with the variance attributed to facility and provider alone and together. We then interviewed 16 emergency department (ED) providers at 8 VA facilities using a cognitive task analysis.

Results

Among 215,803 hospitalizations at 128 VA facilities 1/1/2006-12/31/2016, 31% received empiric anti-MRSA and 29% received empiric anti-PAER antibiotics. Hospitalizations at upper-decile facilities had a 50% and 45% adjusted probability of receiving anti-MRSA and anti-PAER antibiotics, compared to 15% and 20% in the lower-decile facilities. Facility features most predictive of anti-MRSA or anti-PAER use after adjusting for patient characteristics were complexity level (33% and 30% in high versus 15% and 20% in low complexity facilities). Variation in empiric anti-MRSA and anti-PAER use was almost completely at the facility level (Figure 1). Providers reported social influences from the opinions of other providers during decision-making and a high trust in guidelines and order sets. Consideration of pathogens was not mentioned by any providers at high-prescribing facilities.

Conclusion

Variation in empiric use of anti-MRSA and anti-PAER antibiotics in pneumonia clustered nearly completely at the facility level. ED providers report social influences during decision-making and a high trust in guidelines and order sets. Guidelines, order sets, and facility-level clinical champions that promote consideration of pathogens could be important strategies for de-adoption.

Disclosures

All Authors: No reported disclosures

11. Electronic Surveillance Criteria for Non-Ventilator HAP: Empiric testing and Chart Review at Veterans Affairs Facilities

Background

Surveillance of Non-Ventilator Hospital-Acquired Pneumonia (NV-HAP) is limited by the ambiguity in diagnosing pneumonia. We implemented electronic surveillance criteria for NV-HAP across the VA healthcare system and tested for reliability, validity and meaning of the electronic criteria vs manual chart review.

Methods

We defined NV-HAP surveillance criteria as oxygen deterioration concurrent with fever or abnormal WBC count, ≥3 days of antibiotics, and orders for chest imaging. We applied these criteria to EHR data from all patients hospitalized ≥3 days at all VA acute care facilities from 1/1/2015-12/31/2020 and calculated NV-HAP incidence and inpatient mortality. Clinician reviewers used a consensus review guide to independently review and adjudicate 47 cases meeting NV-HAP surveillance criteria for 1) clinical deterioration, 2) CDC-NHSN pneumonia criteria, 3) treating clinicians’ assessment, and 4) reviewer’s diagnosis. All reviewers subsequently adjudicated all cases and conducted an error analysis to identify sources of discordance.

Results

Among 2.3M hospitalizations, 14,023 met NV-HAP surveillance criteria (0.6 per 100 admissions). Inpatient mortality was 26% (vs 2% for non-flagged hospitalizations). Among 47 hospitalizations flagged by surveillance criteria, 45 (97%) had a confirmed clinical deterioration, (the other 2 were immediate post-operative cases), 20 (43%) met CDC-NHSN pneumonia criteria, 21 (47%) had possible pneumonia per treating clinicians, and 25 (53%) had possible or probable NV-HAP per reviewers. Agreement among the 3 reviewers before adjudication was 51% (Fleiss’ κ 0.43) for CDC-NHSN and 58% (Fleiss’ κ 0.33) for NV-HAP. The most common source of discordance between reviewers was chest imaging classification (15/19 discordant cases).

Conclusion

NV-HAP electronic surveillance criteria demonstrated high precision for identifying clinical deterioration and moderate concordance with CDC-NHSN pneumonia criteria or reviewer diagnosis. Agreement between electronic surveillance criteria vs manual chart review was low but similar to agreement amongst manual reviewers applying NHSN criteria. Electronic surveillance may provide greater consistency than human review while facilitating wide-scale automated surveillance.

Disclosures

Chanu Rhee, MD, MPH, UpToDate (Other Financial or Material Support, Chapter Author) Michael Klompas, MD, MPH, UpToDate (Other Financial or Material Support, Chapter Author)

Bread breakdown pathways during mastication: impact of wheat bran fortification

The aim of this study was to investigate the impact of wheat bran fortification on the mastication process of bread. White wheat bread (WB) and bran-fortified wheat bread (BB) were consumed by eighteen panellists. The bolus was collected at four different mastication stages and characterized by properties of hydration, particle size, and texture. The results showed that there was no difference between the two bread samples in terms of swallowable bolus moisture. BB with a harder and denser texture produced more small particles and had a slightly shorter chewing time than WB during mastication. Moreover, bolus heterogeneity (D₇₅/D₂₅) indicated a distinct difference among mastication stages and revealed different disintegration pathways between the two samples: BB bolus exhibited a monotonous particle size reduction during mastication with reducing D₅₀ and D₇₅/D₂₅; whereas, WB displayed a combination pattern of disintegration and agglomeration featuring relatively steady D₅₀ and fluctuating D₇₅/D₂₅. It was concluded that bran fortification changed the bread breakdown pathways in terms of bread disintegration and bolus formation during the mastication process. This information offers new guidelines for fortifying innovative materials to manufacture foods specifically targeted for health.

Probability-Based Estimates of Severe Acute Respiratory Syndrome Coronavirus 2 Seroprevalence and Detection Fraction, Utah, USA

We aimed to generate an unbiased estimate of the incidence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in 4 urban counties in Utah, USA. We used a multistage sampling design to randomly select community-representative participants >12 years of age. During May 4–June 30, 2020, we collected serum samples and survey responses from 8,108 persons belonging to 5,125 households. We used a qualitative chemiluminescent microparticle immunoassay to detect SARS-CoV-2 IgG in serum samples. We estimated the overall seroprevalence to be 0.8%. The estimated seroprevalence-to-case count ratio was 2.5, corresponding to a detection fraction of 40%. Only 0.2% of participants from whom we collected nasopharyngeal swab samples had SARS-CoV-2–positive reverse transcription PCR results. SARS-CoV-2 antibody prevalence during the study was low, and prevalence of PCR-positive cases was even lower. The comparatively high SARS-CoV-2 detection rate (40%) demonstrates the effectiveness of Utah’s testing strategy and public health response.

Abstract 02: Distribution Of Predicted Cardiovascular And All-cause Mortality Benefit Of Intensive Vs Standard Blood Pressure Control Among Us Adults Eligible For The Systolic Blood Pressure Intervention Trial

Introduction: If resources are scarce, achieving national SBP control goals will require prioritizing treatment among those likely to benefit. To identify patients with greatest predicted benefit with intensive SBP treatment and estimate population sizes, we applied algorithms to community samples who met the SPRINT enrollment criteria.

Methods: The published algorithms separately predict the absolute risk reduction in CVD events and mortality at 3.26 years with intensive (<120 mm Hg) vs standard (<140 mm Hg) SBP lowering. We applied and calibrated the algorithms to SPRINT standard arm participants (n=4 399) and samples meeting SPRINT enrollment criteria from the National Health and Nutrition Examination Survey (NHANES, n=1 297) and the Reasons for Geographic And Racial Differences in Stroke (REGARDS, n=2 785). Predicted absolute risk reduction estimated number needed to treat (NNT), categorized as <50, 50-100, and ≥100. Observed 3.26 year CVD event (SPRINT, REGARDS) and mortality rates (all cohorts) were calculated.

Results: The median ages were 67 (SPRINT), 69 (NHANES), and 72 (REGARDS). Greater proportions of NHANES and REGARDS vs SPRINT had predicted NNT <100 for CVD events (NHANES 94.8%, REGARDS 99.2%, SPRINT 87.8%) and mortality (NHANES 64.3%, REGARDS 63.7%, SPRINT 38.8%) ( Table ). Event rates were comparable within NNT groups.

Conclusions: Predicted NNT distributions differ between cohorts but event rates are similar. Most adults who meet SPRINT enrollment criteria have predicted NNT <100 for CVD and mortality with intensive SBP treatment. These results suggest that published algorithms can identify those most likely to benefit and can guide implementation.

Diverse Mucosal-Associated Invariant TCR Usage in HIV Infection

Mucosal-associated invariant T (MAIT) cells are innate-like T cells that specifically target bacterial metabolites but are also identified as innate-like sensors of viral infection. Individuals with chronic HIV-1 infection have lower numbers of circulating MAIT cells compared with healthy individuals, yet the features of the MAIT TCR repertoire are not well known. We isolated and stimulated human PBMCs from healthy non-HIV-infected donors (HD), HIV-infected progressors on antiretroviral therapy, and HIV-infected elite controllers (EC). We sorted MAIT cells using flow cytometry and used a high-throughput sequencing method with bar coding to link the expression of TCRα, TCRβ, and functional genes of interest at the single-cell level. We show differential patterns of MAIT TCR usage among the groups. We observed expansions of certain dominant MAIT clones in HIV-infected individuals upon Escherichia coli stimulation, which was not observed in clones of HD. We also found different patterns of CDR3 amino acid distributions among the three groups. Furthermore, we found blunted expression of phenotypic genes in HIV individuals; most notably, HD mounted a robust IFNG response to stimulation, whereas both HIV-infected progressors and EC did not. In conclusion, our study describes the diverse MAIT TCR repertoire of persons with chronic HIV-1 infection and suggest that MAIT clones of HIV-infected persons may be primed for expansion more than that of noninfected persons. Further studies are needed to examine the functional significance of unique MAIT cell TCR usage in EC.

Patient Selection for Intensive Blood Pressure Management Based on Benefit and Adverse Events

BACKGROUND

Intensive systolic blood pressure (SBP) treatment prevents cardiovascular disease (CVD) events in patients with high CVD risk on average, though benefits likely vary among patients.

OBJECTIVES

The aim of this study was to predict the magnitude of benefit (reduced CVD and all-cause mortality risk) along with adverse event (AE) risk from intensive versus standard SBP treatment.

METHODS

This was a secondary analysis of SPRINT (Systolic Blood Pressure Intervention Trial). Separate benefit outcomes were the first occurrence of: 1) a CVD composite of acute myocardial infarction or other acute coronary syndrome, stroke, heart failure, or CVD death; and 2) all-cause mortality. Treatment-related AEs of interest included hypotension, syncope, bradycardia, electrolyte abnormalities, injurious falls, and acute kidney injury. Modified elastic net Cox regression was used to predict absolute risk for each outcome and absolute risk differences on the basis of 36 baseline variables available at the point of care with intensive versus standard treatment.

RESULTS

Among 8,828 SPRINT participants (mean age 67.9 years, 35% women), 600 CVD composite events, 363 all-cause deaths, and 481 treatment-related AEs occurred over a median follow-up period of 3.26 years. Individual participant risks were predicted for the CVD composite (C index = 0.71), all-cause mortality (C index = 0.75), and treatment-related AEs (C index = 0.69). Higher baseline CVD risk was associated with greater benefit (i.e., larger absolute CVD risk reduction). Predicted CVD benefit and predicted increased treatment-related AE risk were correlated (Spearman correlation coefficient = -0.72), and 95% of participants who fell into the highest tertile of predicted benefit also had high or moderate predicted increases in treatment-related AE risk. Few were predicted as high benefit with low AE risk (1.8%) or low benefit with high AE risk (1.5%). Similar results were obtained for all-cause mortality.

CONCLUSIONS

SPRINT participants with higher baseline predicted CVD risk gained greater absolute benefit from intensive treatment. Participants with high predicted benefit were also most likely to experience treatment-related AEs, but AEs were generally mild and transient. Patients should be prioritized for intensive SBP treatment on the basis of higher predicted benefit. (Systolic Blood Pressure Intervention Trial [SPRINT]; NCT01206062).

Simulated Adoption of 2019 Community-Acquired Pneumonia Guidelines Across 114 Veterans Affairs Medical Centers: Estimated Impact on Culturing and Antibiotic Selection in Hospitalized Patients

BACKGROUND

The 2019 American Thoracic Society/Infectious Diseases Society of America guidelines for community-acquired pneumonia (CAP) revised recommendations for culturing and empiric broad-spectrum antibiotics. We simulated guideline adoption in Veterans Affairs (VA) inpatients.

METHODS

For all VA acute hospitalizations for CAP from 2006-2016 nationwide, we compared observed with guideline-expected proportions of hospitalizations with initial blood and respiratory cultures obtained, empiric antibiotic therapy with activity against methicillin-resistant Staphylococcus aureus (anti-MRSA) or Pseudomonas aeruginosa (antipseudomonal), empiric "overcoverage" (receipt of anti-MRSA/antipseudomonal therapy without eventual detection of MRSA/P. aeruginosa on culture), and empiric "undercoverage" (lack of anti-MRSA/antipseudomonal therapy with eventual detection on culture).

RESULTS

Of 115 036 CAP hospitalizations over 11 years, 17 877 (16%) were admitted to an intensive care unit (ICU). Guideline adoption would slightly increase respiratory culture (30% to 36%) and decrease blood culture proportions (93% to 36%) in hospital wards and increase both respiratory (40% to 100%) and blood (95% to 100%) cultures in ICUs. Adoption would decrease empiric selection of anti-MRSA (ward: 27% to 1%; ICU: 61% to 8%) and antipseudomonal (ward: 25% to 1%; ICU: 54% to 9%) therapies. This would correspond to greatly decreased MRSA overcoverage (ward: 27% to 1%; ICU: 56% to 8%), slightly increased MRSA undercoverage (ward: 0.6% to 1.3%; ICU: 0.5% to 3.3%), with similar findings for P. aeruginosa. For all comparisons, P < .001.

CONCLUSIONS

Adoption of the 2019 CAP guidelines in this population would substantially change culturing and empiric antibiotic selection practices, with a decrease in overcoverage and slight increase in undercoverage for MRSA and P. aeruginosa.

Angiotensin II receptor blocker or angiotensin-converting enzyme inhibitor use and COVID-19-related outcomes among US Veterans

BACKGROUND

Angiotensin II receptor blockers (ARBs) and angiotensin-converting enzyme inhibitors (ACEIs) may positively or negatively impact outcomes in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We investigated the association of ARB or ACEI use with coronavirus disease 2019 (COVID-19)-related outcomes in US Veterans with treated hypertension using an active comparator design, appropriate covariate adjustment, and negative control analyses.

METHODS AND FINDINGS

In this retrospective cohort study of Veterans with treated hypertension in the Veterans Health Administration (01/19/2020-08/28/2020), we compared users of (A) ARB/ACEI vs. non-ARB/ACEI (excluding Veterans with compelling indications to reduce confounding by indication) and (B) ARB vs. ACEI among (1) SARS-CoV-2+ outpatients and (2) COVID-19 hospitalized inpatients. The primary outcome was all-cause hospitalization or mortality (outpatients) and all-cause mortality (inpatients). We estimated hazard ratios (HR) using propensity score-weighted Cox regression. Baseline characteristics were well-balanced between exposure groups after weighting. Among outpatients, there were 5.0 and 6.0 primary outcomes per 100 person-months for ARB/ACEI (n = 2,482) vs. non-ARB/ACEI (n = 2,487) users (HR 0.85, 95% confidence interval [CI] 0.73-0.99, median follow-up 87 days). Among outpatients who were ARB (n = 4,877) vs. ACEI (n = 8,704) users, there were 13.2 and 14.8 primary outcomes per 100 person-months (HR 0.91, 95%CI 0.86-0.97, median follow-up 85 days). Among inpatients who were ARB/ACEI (n = 210) vs. non-ARB/ACEI (n = 275) users, there were 3.4 and 2.0 all-cause deaths per 100 person months (HR 1.25, 95%CI 0.30-5.13, median follow-up 30 days). Among inpatients, ARB (n = 1,164) and ACEI (n = 2,014) users had 21.0 vs. 17.7 all-cause deaths, per 100 person-months (HR 1.13, 95%CI 0.93-1.38, median follow-up 30 days).

CONCLUSIONS

This observational analysis supports continued ARB or ACEI use for patients already using these medications before SARS-CoV-2 infection. The novel beneficial association observed among outpatients between users of ARBs vs. ACEIs on hospitalization or mortality should be confirmed with randomized trials.