e13744 Background: Disparities due to socioeconomic status persist in the treatment of cancer. Newer therapies, such as immune checkpoint inhibitors (ICIs), offer easier administration, lower risk of toxicity, and may improve accessibility compared to cytotoxic chemotherapy. Prior studies on ICI outcomes have shown mixed results at the county level, and there is a need to investigate social determinants of health at a more granular level. Our study aims to compare long-term ICI outcomes between socioeconomic groups at the census tract level among patients with cancer. Methods: The investigators compiled data from 2/1/2011 to 4/7/2022 on patients who received at least one dose of an ICI at a comprehensive cancer center and its outreach clinics to create a retrospective patient registry. Investigators used a secure, cloud-based REDCap registry, validated it with data quality rules, and resolved discrepancies. Clinical research specialists at Vasta Global captured most of the data. Investigators correlated patients’ ZIP codes with 2010 US Department of Agriculture Rural-Urban Commuting Area (RUCA) classifications and census tracts with 2020 Center for Disease Control Social Vulnerability Index (SVI) data. The univariate analyses used the ANOVA or Kruskal-Wallis tests, chi-square tests, and Kaplan-Meier methods. The multivariate analyses used Cox and logistic regressions, adjusting for age, race, ethnicity, type of cancer, smoking status, age-adjusted Charlson Comorbidity Index, and other comorbidities. Results: Our cohort consisted of 1,807 patients who were an average of 66 years old, predominantly male (60.8%), white (84%), non-Hispanic (98%), and had lung cancer (45.1%) as the most common tumor type. Univariate analyses found no associations between either RUCA or SVI and overall survival (OS), progression-free survival (PFS), immune-related adverse events (irAE), or time to irAE. For RUCA, multivariate analysis found that rural location of residence was associated with shorter PFS (all covariates, p 0.0386). For SVI, multivariate analysis showed no significant association with OS, PFS, number of irAEs, or time until irAE (including high-grade irAEs). Conclusions: Rural residence by ZIP code was associated with shorter PFS, indicating that there may be decreased access to ICI for these patients. However, the overall findings suggest similar ICI treatment outcomes across patients with widely variable social determinants of health by census tract. Further research is needed to understand how newer therapies can be best positioned to overcome disparities in cancer care.

e14700 Background: Checkpoint inhibitor pneumonitis (CIP) is the most common high-grade immune-related adverse event among patients with lung cancer. Risk factors for CIP include interstitial lung disease, fibrosis on pre-treatment CT imaging, and likely COPD. This study aims to compare COPD variables and CIP outcomes between cases of high and low-grade CIP, and controls without CIP. We hypothesized that the presence and severity of COPD would affect the evaluation, management, and outcomes of CIP. Methods: From a database of patients with lung cancer who received at least one dose of an immune checkpoint inhibitor between 2/1/11 and 4/7/22 at a comprehensive cancer center, we identified all CIP cases and randomly selected a larger number of controls without CIP. The study team reviewed routine clinical documentation and collected data on pre-treatment respiratory function (e.g., comorbidities, spirometry) and CIP outcomes (e.g., diagnostic testing, interventions, severity). Low-grade (grades 1-2) versus high-grade (grades 3-5) CIP were defined by the Common Terminology Criteria for Adverse Events. We tested categorical variables using Chi-squared or Fisher’s exact test depending on assumptions. We compared continuous variables using the Wilcoxon rank sum or the Kruskall-Wallis test. The database was maintained on a secure, cloud-based REDCap database, validated with data quality rules, and with IRB approval. Results: This study compared 84 cases of CIP (including high-grade CIP in 48/84 cases, 57%) with 252 controls. COPD was a commonly documented comorbidity in both groups (60% cases, 53% controls, p 0.28), although not all patients had spirometry (44% cases, 40% controls). Among the cases, CIP diagnosis occurred at a median of 3 months; at that time, 29% of cases were using a scheduled daily inhaled corticosteroid, and 18% continued to smoke tobacco. Between high-grade and low-grade CIP, there was similar COPD prevalence (64% vs. 56%, p 0.51), severity by forced expiratory volume in one second (FEV1) as a predicted percentage (64 ± 21% vs. 62 ± 16%, p 0.81), and diffusing capacity of the lungs for carbon monoxide as a predicted percentage (62 ± 19% vs. 61 ± 18%, p 0.82). In terms of CIP outcomes, COPD was not associated with the incidence of hospitalization (26/46, 57%, p 0.76), length of hospitalization (8.4 vs. 7.8 days, p=0.33), intensive care unit utilization (10/21, 48%, p 0.52), or death (5/9, 56%, p 0.94). Cardiac evaluation appeared slightly different among patients with COPD (e.g., more often ordered echo; less often ordered BNP or diuresis), although CIP management was overall similar. Conclusions: The presence or severity of pre-treatment COPD was not associated with differences in the management or outcomes of CIP when it occurred. The cardiac evaluation of CIP may have been different because COPD can decrease the specificity of BNP and be less responsive to diuretics.

Abstract Background The COVID-19 pandemic has led to a considerable increase in Central-Line Associated Bloodstream Infections (CLABSI) and Catheter Associated Urinary Tract Infections (CAUTI). However, it remains unclear how this affected different population groups. Methods This retrospective observational cohort study included CLABSI and CAUTI in a tertiary care facility. Information was collected on patient demographics, hospitalization, comorbidities, and COVID-19 status. Chi-square and Wilcoxon rank-sum tests were used for categorical and continuous variable comparisons. GEE models compared pre- and pandemic periods by interrupted time series analysis. Results From 1/1/2018 to 5/31/2022 98,791 patients had 151,550 hospital admissions. Of those, 17,796 patients had 29,483 central lines placed and 45,180 patients had 65,422 Foleys. 314 patients developed 338 CLABSI and 216 patients had 217 CAUTI. 1,552 patients tested positive for COVID-19 with 22 developing CLABSI and 14 CAUTI. The pre-pandemic downward trend in CLABSI and CAUTI was reversed during COVID-19 (p< 0.05). Black patients and those with other/unknown race had higher CLABSI per patient with central lines (p< 0.02) and higher device days (p< 0.0001) compared to white patients. Hispanic/Latino patients acquired more CLABSI per patient compared to non-Hispanic/non-Latino patients (p=0.04). During COVID-19 the already higher device days in Hispanic/Latino patients further increased compared to non-Hispanic/non-Latino patients (p< 0.0001). Black patients had higher CAUTI infection rates per patient with Foleys compared to white and other/unknown patients (p< 0.05). CAUTI per device days were also higher in black patients compared to white patients (p=0.02). No difference in CAUTI burden was detected for ethnic groups throughout the study period. Black and non-Hispanic/non-Latino patients had higher Foley usage days than other patients (p< 0.0001). Foley days decreased during COVID-19 (p=0.01). Conclusion We detected health outcome disparities affecting black (CLABSI and CAUTI) and Hispanic/Latino (CLABSI) patients. Infections increased during the pandemic without altering race/ethnicity differences. Device utilization was significantly higher in affected groups. Disclosures All Authors: No reported disclosures

Though most known for heartburn and regurgitation, gastroesophageal reflux disease (GERD) is attributed to countless atypical, extra-esophageal (EE) manifestations like cough and throat clearing. While GERD has been studied extensively, the relationship between reflux character and symptom manifestation remains poorly understood. The aim of this study was to examine proximal reflux frequency and its relationship with typical or atypical symptoms. 540 (75.1% female, 24.9% male) pH-impedance monitoring studies from the last 3-years were divided by symptom indication and retrospectively reviewed for proximal reflux frequency, total acid exposure time, mean nocturnal baseline impedance, and total reflux episodes in both abnormal and normal, and borderline studies. Baseline characteristics were also collected. Both total reflux events and mean proximal reflux frequency were found to differ significantly between those with typical versus atypical symptoms. Total reflux events [median (IQR)] were 43.5 (24.0-74.0) in typical patients and 35.0 (20.0-57.0) in atypical patients (P-value 0.0369). Proximal reflux frequency [median (IQR)] was 12.0 (4.0-19.0) typical and 7.0 (3.0-17.0) atypical (P-value 0.0348). Results for exclusively abnormal studies also favored typical patients but not significantly. Baseline characteristics and use of gastric acid control did not differ significantly. Proximal reflux frequency was observed to increase among those with typical GERD symptoms. Total acid reflux events were also significantly higher on average with typical patients. Our findings that proximal reflux frequency is reduced in patients with atypical symptoms compared with patients with typical symptoms suggest that proximal reflux exposure may play a significant role in the symptom presentation of typical classic heartburn and regurgitation symptoms. The differential diagnosis for atypical EE symptoms is vast and can be multifactorial. Our results indicate proximal reflux events may contribute to atypical EE symptoms less than previously reported.