Less is more: Streamlining management of isolated traumatic subarachnoid hemorrhage in the modified brain injury guidelines.

BACKGROUND: Patients with isolated traumatic subarachnoid hemorrhage (iTSAH) are managed according to the modified Brain Injury Guidelines (mBIG) class. The current study aimed to describe patients with iTSAH and analyze their clinical outcomes. METHODS: A retrospective analysis was performed on trauma patients with iTSAH. Exclusion criteria were Glasgow Coma Scale (GCS) â€‹< â€‹13 and pre-injury antiplatelet/anticoagulant use. RESULTS: 276 patients were identified over the 8-year study period. The median number of head CT scans was 2. Neurosurgery consultation was obtained in 80.4 â€‹% of patients. A total of 19 (8.6 â€‹%) patients had radiographic progression. Six (2.2 â€‹%) patients had neurologic deterioration. No patients required operative intervention or readmission. No deaths were related to iTSAH. CONCLUSIONS: There were no patients with iTSAH that required neurosurgical consultation despite a subset of patients having radiographic or neurologic progression. These patients may not require repeat head CT scan or neurosurgical consult, necessitating a change of SAH definitions in the mBIG.

Occupational Exposure of On-Shift Ottawa Firefighters to Flame Retardants and Polycyclic Aromatic Hydrocarbons.

Firefighters can be exposed to complex mixtures of airborne substances, including hazardous substances released during structural fires. This study employed silicone wristbands (SWBs) as passive samplers to investigate potential exposure to polycyclic aromatic hydrocarbons (PAHs) and flame retardants (FRs). SWBs were deployed at different areas of four fire stations, in four truck cabins, and at an office control location; they were also donned outside the jackets of 18 firefighters who responded to fire calls. Overall, office areas had significantly lower PAHs than fire station areas. Vehicle bays and truck cabins had significantly higher concentrations of low molecular weight (LMW) PAHs than sleeping and living room areas. For organophosphate ester flame retardants (OPFRs), tri-n-butyl phosphate (TnBP) and tris(1-chloro-2-propyl) phosphate (TCPP) were detected in all the samples; 2-ethylhexyl diphenyl phosphate (EHDPP) was more frequently detected in the fire station areas. Triphenyl phosphate (TPP) concentrations were highest in the truck cabin and office areas, and tris(1,3-dichloro-2-propyl)phosphate (TDCPP) was highest in truck cabins. Thirteen of 16 PAHs and nine of 36 OPFRs were detected in all the SWBs worn by firefighters, and tris (2-butoxyethyl) phosphate (TBEP) was the predominant OPFR. Levels of LMW PAHs were significantly lower when firefighters did not enter the fire. LMW PAHs, HMW (high molecular weight) PAHs, and EHDPP were significantly elevated when heavy smoke was reported. This work highlights the potential for occupational exposure to PAHs and flame retardants in some fire station areas; moreover, factors that may influence exposure during fire suppression. Whilst firefighters' occupational exposure to PAHs is likely related to fire suppression and exposure to contaminated gear and trucks, exposure to OPFRs may be more related to their presence in truck interiors and electronics.

In Vivo Evolution of a Klebsiella pneumoniae Capsule Defect With wcaJ Mutation Promotes Complement-Mediated Opsonophagocytosis During Recurrent Infection.

BACKGROUND: Klebsiella pneumoniae carbapenemase-producing K pneumoniae (KPC-Kp) bloodstream infections are associated with high mortality. We studied clinical bloodstream KPC-Kp isolates to investigate mechanisms of resistance to complement, a key host defense against bloodstream infection. METHODS: We tested growth of KPC-Kp isolates in human serum. In serial isolates from a single patient, we performed whole genome sequencing and tested for complement resistance and binding by mixing study, direct enzyme-linked immunosorbent assay, flow cytometry, and electron microscopy. We utilized an isogenic deletion mutant in phagocytosis assays and an acute lung infection model. RESULTS: We found serum resistance in 16 of 59 (27%) KPC-Kp clinical bloodstream isolates. In 5 genetically related bloodstream isolates from a single patient, we noted a loss-of-function mutation in the capsule biosynthesis gene, wcaJ. Disruption of wcaJ was associated with decreased polysaccharide capsule, resistance to complement-mediated killing, and surprisingly, increased binding of complement proteins. Furthermore, an isogenic wcaJ deletion mutant exhibited increased opsonophagocytosis in vitro and impaired in vivo control in the lung after airspace macrophage depletion in mice. CONCLUSIONS: Loss of function in wcaJ led to increased complement resistance, complement binding, and opsonophagocytosis, which may promote KPC-Kp persistence by enabling coexistence of increased bloodstream fitness and reduced tissue virulence.

Targeted degradation of extracellular mitochondrial aspartyl-tRNA synthetase modulates immune responses.

The severity of bacterial pneumonia can be worsened by impaired innate immunity resulting in ineffective pathogen clearance. We describe a mitochondrial protein, aspartyl-tRNA synthetase (DARS2), which is released in circulation during bacterial pneumonia in humans and displays intrinsic innate immune properties and cellular repair properties. DARS2 interacts with a bacterial-induced ubiquitin E3 ligase subunit, FBXO24, which targets the synthetase for ubiquitylation and degradation, a process that is inhibited by DARS2 acetylation. During experimental pneumonia, Fbxo24 knockout mice exhibit elevated DARS2 levels with an increase in pulmonary cellular and cytokine levels. In silico modeling identified an FBXO24 inhibitory compound with immunostimulatory properties which extended DARS2 lifespan in cells. Here, we show a unique biological role for an extracellular, mitochondrially derived enzyme and its molecular control by the ubiquitin apparatus, which may serve as a mechanistic platform to enhance protective host immunity through small molecule discovery.

The size paradox: An analysis of tube thoracostomy in trauma.

BACKGROUND: Debate continues over chest tube (CT) size for traumatic hemothorax (HTX) and pneumothorax (PTX). We compared CT failure and opioid use between large-bore chest tubes (LB-CT) and small-bore chest tubes (SB-CT). METHODS: A retrospective study comparing trauma patients with SB-CT (≤14Fr) or LB-CT (≥24Fr) was performed. CT failure includes HTX, PTX, or empyema requiring intervention. Secondary outcomes included opioid use (MME), mortality, and favorable discharge. RESULTS: Of 252 patients, 65.1 â€‹% had SB-CT. SB-CT were older with lower ISS. Failure rate was lower for SB-CT (9.2 vs 22.7 â€‹%, p â€‹= â€‹0.003), as was opioid use (332 vs 767, p â€‹< â€‹0.001). In adjusted analysis there was no difference in CT failure between SB-CT and LB-CT. Subgroup analysis found SB-CT had lower total MME (234 vs 342, p â€‹= â€‹0.018). CONCLUSIONS: This study found no major differences in CT failure or opioid use by CT size, suggesting SB-CT are a safe, and effective alternative to LB-CT in trauma.

Noninvasive assessment of the lung inflammation-fibrosis axis by targeted imaging of CMKLR1.

Precision management of fibrotic lung diseases is challenging due to their diverse clinical trajectories and lack of reliable biomarkers for risk stratification and therapeutic monitoring. Here, we validated the accuracy of CMKLR1 as an imaging biomarker of the lung inflammation-fibrosis axis. By analyzing single-cell RNA sequencing datasets, we demonstrated CMKLR1 expression as a transient signature of monocyte-derived macrophages (MDMφ) enriched in patients with idiopathic pulmonary fibrosis (IPF). Consistently, we identified MDMφ as the major driver of the uptake of CMKLR1-targeting peptides in a murine model of bleomycin-induced lung fibrosis. Furthermore, CMKLR1-targeted positron emission tomography in the murine model enabled quantification and spatial mapping of inflamed lung regions infiltrated by CMKLR1-expressing macrophages and emerged as a robust predictor of subsequent lung fibrosis. Last, high CMKLR1 expression by bronchoalveolar lavage cells identified an inflammatory endotype of IPF with poor survival. Our investigation supports the potential of CMKLR1 as an imaging biomarker for endotyping and risk stratification of fibrotic lung diseases.

Neutrophils and galectin-3 defend mice from lethal bacterial infection and humans from acute respiratory failure.

Respiratory infection by Pseudomonas aeruginosa, common in hospitalized immunocompromised and immunocompetent ventilated patients, can be life-threatening because of antibiotic resistance. This raises the question of whether the host's immune system can be educated to combat this bacterium. Here we show that prior exposure to a single low dose of lipopolysaccharide (LPS) protects mice from a lethal infection by P. aeruginosa. LPS exposure trained the innate immune system by promoting expansion of neutrophil and interstitial macrophage populations distinguishable from other immune cells with enrichment of gene sets for phagocytosis- and cell-killing-associated genes. The cell-killing gene set in the neutrophil population uniquely expressed Lgals3, which encodes the multifunctional antibacterial protein, galectin-3. Intravital imaging for bacterial phagocytosis, assessment of bacterial killing and neutrophil-associated galectin-3 protein levels together with use of galectin-3-deficient mice collectively highlight neutrophils and galectin-3 as central players in LPS-mediated protection. Patients with acute respiratory failure revealed significantly higher galectin-3 levels in endotracheal aspirates (ETAs) of survivors compared to non-survivors, galectin-3 levels strongly correlating with a neutrophil signature in the ETAs and a prognostically favorable hypoinflammatory plasma biomarker subphenotype. Taken together, our study provides impetus for harnessing the potential of galectin-3-expressing neutrophils to protect from lethal infections and respiratory failure.

Clinical and economic outcomes associated with lymph node examination status in early-stage non-small cell lung cancer: a real-world US study using the SEER-Medicare linked database.

Background: Clinical practice guidelines recommend adjuvant therapy for patients with early non-small cell lung cancer (eNSCLC), especially those with lymph node metastasis. This study evaluated the prevalence of lymph node examination and its association with adjuvant treatment rates, overall survival (OS), and healthcare costs among United States (US) Medicare patients with resected eNSCLC. Methods: This retrospective observational cohort study used Surveillance, Epidemiology, and End Results cancer registry data linked with Medicare claims data. Eligible patients were aged ≥65 years with newly diagnosed non-small cell lung cancer (NSCLC) stages IA to IIIB [the American Joint Committee on Cancer (AJCC) Cancer Staging Manual, 7th edition] between January 2010 and December 2017 with surgery ≤1 month prior to or ≤12 months after diagnosis. Patients were grouped by lymph node examination status: no examination (pNX), examination and no metastasis (pN0), or metastasis staging in N1 (pN1) or N2 (pN2). OS and costs were evaluated by examination status and number of lymph node examined. OS was analyzed using extended Cox proportional hazards models for specific time periods and time interaction with examination status, and adjusted for patient characteristics. Adjusted post-surgical healthcare costs per patient per month (PPPM) were analyzed using gamma-log regression models. Results: Among the 14,648 patients included in the study, approximately 11% were pNX, whereas most were pN0 (68%), followed by pN1 (11%) and pN2 (10%). Adjuvant treatment rates were higher for pNX (35%) than pN0 (18%), but lower than pN1 (68%) and pN2 (74%) patients (P<0.001). Unadjusted OS for pNX patients was nearly identical to pN2, and significantly worse compared to pN0 and pN1 (P<0.0001). After adjusting for patient characteristics, pNX patients had higher risk of death relative to pN0 patients (P<0.001). Marginal mean adjusted total costs were comparable across pNX ($15,827 PPPM), pN0 ($12,712 PPPM) and pN1 ($17,089 PPPM), but significantly less for pN0 compared to pN2 ($23,566 PPPM) (P=0.002). Conclusions: Inadequate lymph node examination is associated with underutilization of adjuvant treatment and poor OS in resected NSCLC. In the current era of targeted and immunotherapies, lymph node examination is more important than ever, implicating the need for Quality Improvement practices and multidisciplinary coordination.

Increased Neutrophil H2O2 Production and Enhanced Pulmonary Clearance of Klebsiella pneumoniae in G6PD A- Mice.

The X-linked A- variant (rs1050828, Val68Met) in G6PDX accounts for glucose-6-phosphate (G6PD) deficiency in approximately 11% of African American males. This common, hypomorphic variant may impact pulmonary host defense and phagocyte function during pneumonia by altering levels of reactive oxygen species produced by host leukocytes. We used CRISPR-Cas9 technology to generate novel mouse strain with "humanized" G6PD A- variant containing non-synonymous Val68Met single nucleotide polymorphism. Male hemizygous or littermate wild-type (WT) controls were inoculated intratracheally with K. pneumoniae (KP2 serotype, ATCC 43816 strain,103 CFU inoculum). We examined leukocyte recruitment, organ bacterial burden, bone marrow neutrophil and macrophage (BMDM) phagocytic capacity, and hydrogen peroxide (H2O2) production. Unexpectedly, G6PD-deficient mice showed decreased lung bacterial burden (p=0.05) compared to controls 24-h post-infection. Extrapulmonary dissemination and bacteremia were significantly reduced in G6PD-deficient mice 48-h post-infection. Bronchoalveolar lavage fluid (BALF) IL-10 levels were elevated in G6PD-deficient mice (p=0.03) compared to controls at 24-h but were lower at 48-h (p=0.03). G6PD A- BMDMs show mildly decreased in vitro phagocytosis of pHrodo-labeled KP2 (p=0.03). Baseline, but not stimulated, H2O2 production by G6PD A- neutrophils was greater compared to WT neutrophils. G6PD A- variant demonstrate higher basal neutrophil H2O2 production and are protected against acute Klebsiella intrapulmonary infection.

Association Between Intensity and Timing of Specialty Palliative Care and Hospice Exposure With Quality of End-of-Life Care.

Background: Gaps remain in our understanding of the intensity and timing of specialty palliative care (SPC) exposure on end-of-life (EOL) outcomes. Objective: Examine the association between intensity and timing of SPC and hospice (HO) exposure on EOL care outcomes. Design, Settings, Participants: Data for this cohort study were drawn from 2021 adult decedents from Kaiser Permanente Southern California and Colorado (n = 26,251). Caregivers of a decedent subgroup completed a postdeath care experience survey from July to August 2022 (n = 424). Measurements: SPC intensity (inpatient, outpatient, and home-based) and HO exposure in the five years before death were categorized as: (1) No SPC or HO; (2) SPC-only; (3) HO-only; and (4) SPC-HO. Timing of SPC exposure (<90 or 90+ days) before death was stratified by HO enrollment. Death in the hospital and potentially burdensome treatments in the last 14 days of life were extracted from electronic medical records (EMRs) and claims. EOL care experience was obtained from the caregiver survey. Results: Among the EMR cohort, exposure to SPC and HO were: No SPC or HO (38%), SPC-only (14%; of whom, 55% received inpatient SPC only), HO-only (20%), and SPC-HO (28%). For decedents who did not enroll in HO, exposure to SPC 90+ days versus <90 days before death was associated with lower risk of receiving potentially burdensome treatments (adjusted relative risk, aRR: 0.69 [95% confidence interval, CI: 0.62-0.76], p < 0.001) and 23% lower risk of dying in the hospital (aRR: 0.77 [95% CI: 0.73-0.81], p < 0.001). Caregivers of patients in the HO-only (aRR: 1.27 [95% CI: 0.98-1.63], p = 0.07) and SPC-HO cohorts (aRR: 1.19 [95% CI: 0.93-1.52], p = 0.18) tended to report more positive care experience compared to the no SPC or HO cohort. Conclusion: Earlier exposure to SPC was important in reducing potentially burdensome treatments and death in the hospital for decedents who did not enroll in HO. Increasing availability and access to community-based SPC is needed.

Socioeconomic factors associated with uptake and satisfaction with a post-hospitalization meals benefit in Medicare Advantage.

BACKGROUND: Kaiser Permanente Southern California began offering a 4-week supplemental benefit of home-delivered meals to Medicare Advantage members after discharge from a hospitalization for heart failure and other medical conditions in 2021. The purpose of this study is to explore the associations between socioeconomic disadvantage and food insecurity with patient uptake of and satisfaction with the meals. METHODS: Data for this cross-sectional study were drawn from survey and electronic medical record data for members referred for the meals benefit (n = 6169) and linked to a hospitalization encounter (n = 2254) between January and December 2021. Uptake was assessed using vendor records; measures of socioeconomic status included the neighborhood deprivation index (NDI) and prior receipt of medical financial assistance (MFA) from the health system. Patients were invited to complete an email or phone survey about their satisfaction with the meals and food insecurity. Multivariable log-binomial regression models were used to examine the association between socioeconomic disadvantage and food insecurity with meals uptake and satisfaction. RESULTS: Sixty-two percent of patients referred for the benefit accepted the meals (mean age: 79 ± 9, 59% people of color). While there was no significant relationship between NDI and meals uptake (RR: 0.99, 95% CI: 0.92-1.07, p = 0.77), patients who received prior MFA were more likely to accept the meals (RR: 1.09, 95% CI: 1.02-1.16, p < 0.01). Sixty-nine percent of patients who completed the survey (23% response rate) reported that meals were very or extremely helpful. Patients with food insecurity (29% of survey respondents) were more likely to report that the meals were helpful for their recovery compared to food secure patients (RR: 1.21, 95% CI: 1.09-1.35, p < 0.01). CONCLUSIONS: The home-delivered meals appeared to be particularly utilized by and helpful to patients with greater financial strain and/or food insecurity, suggesting that supplemental benefits could be more targeted toward addressing unmet needs of vulnerable adults.

Functional effects of an African glucose-6-phosphate dehydrogenase (G6PD) polymorphism (Val68Met) on red blood cell hemolytic propensity and post-transfusion recovery.

BACKGROUND: Donor genetic variation is associated with red blood cell (RBC) storage integrity and post-transfusion recovery. Our previous large-scale genome-wide association study demonstrated that the African G6PD deficient A- variant (rs1050828, Val68Met) is associated with higher oxidative hemolysis after cold storage. Despite a high prevalence of X-linked G6PD mutation in African American population (>10%), blood donors are not routinely screened for G6PD status and its importance in transfusion medicine is relatively understudied. STUDY DESIGN AND METHODS: To further evaluate the functional effects of the G6PD A- mutation, we created a novel mouse model carrying this genetic variant using CRISPR-Cas9. We hypothesize that this humanized G6PD A- variant is associated with reduced G6PD activity with a consequent effect on RBC hemolytic propensity and post-transfusion recovery. RESULTS: G6PD A- RBCs had reduced G6PD protein with ~5% residual enzymatic activity. Significantly increased in vitro hemolysis induced by oxidative stressors was observed in fresh and stored G6PD A- RBCs, along with a lower GSH:GSSG ratio. However, no differences were observed in storage hemolysis, osmotic fragility, mechanical fragility, reticulocytes, and post-transfusion recovery. Interestingly, a 14% reduction of 24-h survival following irradiation was observed in G6PD A- RBCs compared to WT RBCs. Metabolomic assessment of stored G6PD A- RBCs revealed an impaired pentose phosphate pathway (PPP) with increased glycolytic flux, decreasing cellular antioxidant capacity. DISCUSSION: This novel mouse model of the common G6PD A- variant has impaired antioxidant capacity like humans and low G6PD activity may reduce survival of transfused RBCs when irradiation is performed.

Lung Epithelium Releases Growth Differentiation Factor 15 in Response to Pathogen-mediated Injury.

GDF15 (growth differentiation factor 15) is a stress cytokine with several proposed roles, including support of stress erythropoiesis. Higher circulating GDF15 levels are prognostic of mortality during acute respiratory distress syndrome, but the cellular sources and downstream effects of GDF15 during pathogen-mediated lung injury are unclear. We quantified GDF15 in lower respiratory tract biospecimens and plasma from patients with acute respiratory failure. Publicly available data from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection were reanalyzed. We used mouse models of hemorrhagic acute lung injury mediated by Pseudomonas aeruginosa exoproducts in wild-type mice and mice genetically deficient for Gdf15 or its putative receptor, Gfral. In critically ill humans, plasma levels of GDF15 correlated with lower respiratory tract levels and were higher in nonsurvivors. SARS-CoV-2 infection induced GDF15 expression in human lung epithelium, and lower respiratory tract GDF15 levels were higher in coronavirus disease (COVID-19) nonsurvivors. In mice, intratracheal P. aeruginosa type II secretion system exoproducts were sufficient to induce airspace and plasma release of GDF15, which was attenuated with epithelial-specific deletion of Gdf15. Mice with global Gdf15 deficiency had decreased airspace hemorrhage, an attenuated cytokine profile, and an altered lung transcriptional profile during injury induced by P. aeruginosa type II secretion system exoproducts, which was not recapitulated in mice deficient for Gfral. Airspace GDF15 reconstitution did not significantly modulate key lung cytokine levels but increased circulating erythrocyte counts. Lung epithelium releases GDF15 during pathogen injury, which is associated with plasma levels in humans and mice and can increase erythrocyte counts in mice, suggesting a novel lung-blood communication pathway.

Siderophores promote cooperative interspecies and intraspecies cross-protection against antibiotics in vitro.

The antibiotic cefiderocol hijacks iron transporters to facilitate its uptake and resists ß-lactamase degradation. While effective, resistance has been detected clinically with unknown mechanisms. Here, using experimental evolution, we identified cefiderocol resistance mutations in Pseudomonas aeruginosa. Resistance was multifactorial in host-mimicking growth media, led to multidrug resistance and paid fitness costs in cefiderocol-free environments. However, kin selection drove some resistant populations to cross-protect susceptible individuals from killing by increasing pyoverdine secretion via a two-component sensor mutation. While pyochelin sensitized P. aeruginosa to cefiderocol killing, pyoverdine and the enterobacteria siderophore enterobactin displaced iron from cefiderocol, preventing uptake by susceptible cells. Among 113 P. aeruginosa intensive care unit clinical isolates, pyoverdine production directly correlated with cefiderocol tolerance, and high pyoverdine producing isolates cross-protected susceptible P. aeruginosa and other Gram-negative bacteria. These in vitro data show that antibiotic cross-protection can occur via degradation-independent mechanisms and siderophores can serve unexpected protective cooperative roles in polymicrobial communities.

Effectiveness and safety of early treatment with spironolactone for new-onset acute heart failure.

BACKGROUND: The effectiveness and safety of mineralocorticoid receptor antagonists (MRA) in acute heart failure (HF) is uncertain. We sought to describe the prescription of spironolactone during acute HF and whether early treatment is effective and safe in a real-world setting. METHODS: We performed a retrospective cohort study of adult (≥18 years) nonpregnant patients hospitalized with new-onset HF with reduced ejection fraction (HFrEF, defined by ejection fraction ≤40%) within 15 Kaiser Permanente Southern California medical centers between 2016 and 2021. Early treatment was defined by spironolactone prescription at discharge. The primary effectiveness outcome was a composite of HF readmission or all-cause mortality at 180 days. Safety outcomes were hypotension and hyperkalemia at 90 days. RESULTS: Among 2318 HFrEF patients, 368 (15.9%) were treated with spironolactone at discharge. After 1:2 propensity score matching, 354 early treatment and 708 delayed/no treatment patients were included in the analysis. The median age was 63 (IQR: 52-74) years; 61.6% were male, and 38.6% were White. By 90 days, ~20% had crossed over in the two groups. Early treatment was not associated with the composite outcome at 180 days (HR [95% CI]: 0.81 [0.56-1.17]), but a trend towards benefit by 365 days that did not reach statistical significance (0.78 [0.58-1.06]). Early treatment was also associated with hyperkalemia (subdistribution HR [95% CI]: 2.33 [1.30-4.18]) but not hypotension (0.93 [0.51-1.72]). CONCLUSIONS: Early treatment with spironolactone at discharge for new-onset HFrEF in a real-world setting did not reduce the risk of HF readmission or mortality in the first year after discharge. The risk of hyperkalemia was increased.

Association Between Coronary Artery Disease Testing in Patients with New-Onset Heart Failure and Heart Failure Readmission and Mortality.

BACKGROUND: In patients with new-onset heart failure (HF), coronary artery disease (CAD) testing remains underutilized. Whether widespread CAD testing in patients with new-onset HF leads to improved outcomes remains to be determined. OBJECTIVE: We sought to examine whether CAD testing, and its timing, among patients hospitalized with new-onset HF with reduced ejection fraction (HFrEF), is associated with improved outcomes. DESIGN: Retrospective cohort study. PARTICIPANTS: Adult (≥ 18 years) non-pregnant patients with new-onset HFrEF hospitalized within one of 15 Kaiser Permanente Southern California medical centers between 2016 and 2021. Key exclusion criteria included history of heart transplant, hospice, and a do-not-resuscitate order. MAIN MEASURES: Primary outcome was a composite of HF readmission or all-cause mortality through end of follow-up on 12/31/2022. KEY RESULTS: Among 2729 patients hospitalized with new-onset HFrEF, 1487 (54.5%) received CAD testing. The median age was 66 (56-76) years old, 1722 (63.1%) were male, and 1074 (39.4%) were White. After a median of 1.8 (0.6-3.4) years, the testing group had a reduced risk of HF readmission or all-cause mortality (aHR [95%CI], 0.71 [0.63-0.79]). These results were consistent across subgroups by history of atrial fibrillation, diabetes, renal disease, myocardial infarction, and elevated troponin during hospitalization. In a secondary analysis where CAD testing was further divided to early (received testing before discharge) and late testing (up to 90 days after discharge), there was no difference in late vs early testing (0.97 [0.81-1.16]). CONCLUSIONS: In a contemporary and diverse cohort of patients hospitalized with new-onset HFrEF, CAD testing within 90 days of hospitalization was associated with a lower risk of HF readmission or all-cause mortality. Testing within 90 days after discharge was not associated with worse outcomes.