Janet P. Tate

INTRODUCTION: Early detection of pancreatic ductal adenocarcinoma (PDAC) improves survival. However, screening recommendations are limited to individuals with hereditary risk, accounting for only 10% of PDAC. We explore the feasibility of developing and validating an electronic health record-based model to identify high-risk individuals for PDAC screening within the asymptomatic general population. METHODS: Using multivariable Cox regression, we developed a diagnostic model to predict time to PDAC within 3 years in the Veterans Health Administration. We evaluated the final model using internal and temporally separate data sets using Akaike Information Criterion, Harrell c statistic, calibration curves, and sensitivity/specificity corresponding to a 3-year risk screening threshold of 1%. RESULTS: Among 9,351,261 individuals, 26,119 (0.3%) developed PDAC (107.6 cases per 100,000 person-years) within 3 years. The final model included age, pancreatic cyst, pancreatitis, smoking status, history of a localized solid tumor, race/ethnicity, and body mass index. Glucose and albumin values were highly important, in addition to other metabolic, inflammatory, and liver-related laboratory values. The c statistic (95% CI) was 0.75 (0.75–0.76) in development, 0.75 (0.75–0.76) in internal validation, and 0.74 (0.73–0.75) in temporal validation. At a 3-year risk threshold of 1.0%, 11% of the population would undergo screening, capturing 30% of the PDAC cases. DISCUSSION: We demonstrate good model discrimination in independent data. Compared with current screening practices targeting only genetically predisposed individuals, its implementation could identify 3 times as many PDAC cases. However, predictors beyond the electronic health record (EHR) may be needed to further improve the feasibility of generalized screening.

This diagnostic study validates hepatocellular carcinoma risk scores without alcohol measures in veterans with and without alcohol use disorder.

Importance: Hepatocellular carcinoma (HCC) is typically detected only at advanced stages when treatment options are limited. Most of the current HCC risk models focus on patients with viral hepatitis or diagnosed cirrhosis or require variables not routinely available in clinical care. Objective: To identify modifiable HCC risk factors in the general population and to develop a risk score to inform HCC screening and risk-factor modification interventions for high-risk individuals without viral hepatitis or decompensated cirrhosis. Design, Setting, and Participants: This cohort study analyzed demographic, clinical, laboratory, and diagnostic data from the US Department of Veterans Affairs (VA) electronic health records. Data were divided into development and validation samples. Veterans aged 30 to 95 years were included, and those with hepatitis B or C virus infection, hepatic decompensation, or prevalent HCC were excluded. Patients were followed up until the occurrence of HCC diagnosis, death, or December 31, 2021. A Cox proportional hazards regression model for 10-year risk of HCC was developed and used to create an HCC risk score, and performance in development and validation samples and in patient subgroups was evaluated. One outpatient visit date per person at least 18 months after VA entry, between October 1, 2007, and March 31, 2020, was randomly selected and used as the index date for the start of follow-up. Analyses were performed from March 2023 to May 2024. Exposures: Age, sex, race and ethnicity, body mass index, liver fibrosis (detected with Fibrosis-4 Index [FIB-4]), diabetes status, smoking status, and alcohol use. Main Outcomes and Measures: First HCC diagnosis during follow-up. This information was ascertained from VA national cancer registry topography and histology codes and from International Classification of Diseases, Ninth Revision and International Statistical Classification of Diseases, Tenth Revision, Clinical Modification diagnosis codes for the inpatient or outpatient visits. Results: This study of 6 509 288 veterans included 6 048 917 males (92.9%), with a median (IQR) age of 65 (54-74) years, who identified as being of Hispanic (5.3%), non-Hispanic Black (15.0%), non-Hispanic White (68.9%), or other (4.6%) race and ethnicity. Overall, 15 142 patients (0.2%) developed HCC, 69.5% of whom had FIB-4 of 3.25 or lower at baseline. While FIB-4 was the most important variable, age, sex, race and ethnicity, body mass index, diabetes, smoking, and alcohol use were also informative. Discrimination in the development sample was better than FIB-4 alone (C statistic, 0.83 [95% CI, 0.82-0.85] vs 0.79 [95% CI, 0.77-0.80]). The HCC risk score performed consistently well in the validation sample and in all subgroups. A FIB-4 threshold of 3.25 would screen 5.0% of the cohort at a cost of 28 false-positives for every true-positive; a model risk score of 58 would screen 4.7% of the cohort at a cost of 23 false-positives for every true-positive. Conclusions and Relevance: Results of this study suggest that a multivariable risk score that uses routinely available clinical data outperforms FIB-4 alone in identifying patients at risk of HCC who do not have viral hepatitis or hepatic decompensation at baseline.

Background: Steatotic liver disease (SLD) is a growing phenomenon, and our understanding of its determinants has been limited by our ability to identify it clinically. Natural language processing (NLP) can potentially identify hepatic steatosis systematically within large clinical repositories of imaging reports. We validated the performance of an NLP algorithm for the identification of SLD in clinical imaging reports and applied this tool to a large population of people with and without HIV. Methods: Patients were included in the analysis if they enrolled in the Veterans Aging Cohort Study between 2001 and 2017, had an imaging report inclusive of the liver, and had ≥2 years of observation before the imaging study. SLD was considered present when reports contained the terms “fatty,” “steatosis,” “steatotic,” or “steatohepatitis.” The performance of the SLD NLP algorithm was compared to a clinical review of 800 reports. We then applied the NLP algorithm to the first eligible imaging study and compared patient characteristics by SLD and HIV status. Results: NLP achieved 100% sensitivity and 88.5% positive predictive value for the identification of SLD. When applied to 26,706 eligible Veterans Aging Cohort Study patient imaging reports, SLD was identified in 72.2% and did not significantly differ by HIV status. SLD was associated with a higher prevalence of metabolic comorbidities, alcohol use disorder, and hepatitis B and C, but not HIV infection. Conclusions: While limited to those undergoing radiologic study, the NLP algorithm accurately identified SLD in people with and without HIV and offers a valuable tool to evaluate the determinants and consequences of hepatic steatosis.

Importance: Deaths among patients with coronavirus disease 2019 (COVID-19) are partially attributed to venous thromboembolism and arterial thromboses. Anticoagulants prevent thrombosis formation, possess anti-inflammatory and anti-viral properties, and may be particularly effective for treating patients with COVID-19. Objective: To evaluate whether initiation of prophylactic anticoagulation within 24 hours of admission is associated with decreased risk of death among patients hospitalized with COVID-19. Design: Observational cohort study. Setting: Nationwide cohort of patients receiving care in the Department of Veterans Affairs, the largest integrated healthcare system in the United States. Participants: All patients hospitalized with laboratory-confirmed SARS-CoV-2 infection March 1 to July 31, 2020, without a history of therapeutic anticoagulation. Exposures: Prophylactic doses of subcutaneous heparin, low-molecular-weight heparin, or direct oral anticoagulants. Main Outcomes and Measures: 30-day mortality. Secondary outcomes: inpatient mortality and initiating therapeutic anticoagulation. Results: Of 4,297 patients hospitalized with COVID-19, 3,627 (84.4%) received prophylactic anticoagulation within 24 hours of admission. More than 99% (n=3,600) received subcutaneous heparin or enoxaparin. We observed 622 deaths within 30 days of admission, 513 among those who received prophylactic anticoagulation. Most deaths (510/622, 82%) occurred during hospitalization. In inverse probability of treatment weighted analyses, cumulative adjusted incidence of mortality at 30 days was 14.3% (95% CI 13.1-15.5) among those receiving prophylactic anticoagulation and 18.7% (95% CI 15.1-22.9) among those who did not. Compared to patients who did not receive prophylactic anticoagulation, those who did had a 27% decreased risk for 30-day mortality (HR 0.73, 95% CI 0.66-0.81). Similar associations were found for inpatient mortality and initiating therapeutic anticoagulation. Quantitative bias analysis demonstrated that results were robust to unmeasured confounding (e-value lower 95% CI 1.77). Results persisted in a number of sensitivity analyses. Conclusions and Relevance: Early initiation of prophylactic anticoagulation among patients hospitalized with COVID-19 was associated with a decreased risk of mortality. These findings provide strong real-world evidence to support guidelines recommending the use of prophylactic anticoagulation as initial therapy for COVID-19 patients upon hospital admission.

Background: There is growing concern that racial and ethnic minority communities around the world are experiencing a disproportionate burden of morbidity and mortality from symptomatic SARS-Cov-2 infection or coronavirus disease 2019 (Covid-19). Most studies investigating racial and ethnic disparities to date have focused on hospitalized patients or have not characterized who received testing or those who tested positive for Covid-19. Objective: To compare patterns of testing and test results for coronavirus 2019 (Covid-19) and subsequent mortality by race and ethnicity in the largest integrated healthcare system in the United States. Design: Retrospective cohort study. Setting: United States Department of Veterans Affairs (VA). Participants: 5,834,543 individuals in care, among whom 62,098 were tested and 5,630 tested positive for Covid-19 between February 8 and May 4, 2020. Exposures: Self-reported race/ethnicity. Main outcome measures: We evaluated associations between race/ethnicity and receipt of Covid-19 testing, a positive test result, and 30-day mortality, accounting for a wide range of demographic and clinical risk factors including comorbid conditions, site of care, and urban versus rural residence. Results: Among all individuals in care, 74% were non-Hispanic white (white), 19% non-Hispanic black (black), and 7% Hispanic. Compared with white individuals, black and Hispanic individuals were more likely to be tested for Covid-19 (tests per 1000: white=9.0, [95% CI 8.9 to 9.1]; black=16.4, [16.2 to 16.7]; and Hispanic=12.2, [11.9 to 12.5]). While individuals from minority backgrounds were more likely to test positive (black vs white: OR 1.96, 95% CI 1.81 to 2.12; Hispanic vs white: OR 1.73, 95% CI 1.53 to 1.96), 30-day mortality did not differ by race/ethnicity (black vs white: OR 0.93, 95% CI 0.64 to 1.33; Hispanic vs white: OR 1.07, 95% CI 0.61 to 1.87). Conclusions: Black and Hispanic individuals are experiencing an excess burden of Covid-19 not entirely explained by underlying medical conditions or where they live or receive care. While there was no observed difference in mortality by race or ethnicity, our findings may underestimate risk in the broader US population as health disparities tend to be reduced in VA.

Importance: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection causes coronavirus disease 2019 (Covid-19), an evolving pandemic. Limited data are available characterizing SARS-Cov-2 infection in the United States. Objective: To determine associations between demographic and clinical factors and testing positive for coronavirus 2019 (Covid-19+), and among Covid-19+ subsequent hospitalization and intensive care. Design, Setting, and Participants: Retrospective cohort study including all patients tested for Covid-19 between February 8 and March 30, 2020, inclusive. We extracted electronic health record data from the national Veterans Affairs Healthcare System, the largest integrated healthcare system in the United States, on 2,026,227 patients born between 1945 and 1965 and active in care. Exposures: Demographic data, comorbidities, medication history, substance use, vital signs, and laboratory measures. Laboratory tests were analyzed first individually and then grouped into a validated summary measure of physiologic injury (VACS Index). Main Outcomes and Measures: We evaluated which factors were associated with Covid-19+ among all who tested. Among Covid-19+ we identified factors associated with hospitalization or intensive care. We identified independent associations using multivariable and conditional multivariable logistic regression with multiple imputation of missing values. Results: Among Veterans aged 54-75 years, 585/3,789 (15.4%) tested Covid-19+. In adjusted analysis (C-statistic=0.806) black race was associated with Covid-19+ (OR 4.68, 95% CI 3.79-5.78) and the association remained in analyses conditional on site (OR 2.56, 95% CI 1.89-3.46). In adjusted models, laboratory abnormalities (especially fibrosis-4 score [FIB-4] >3.25 OR 8.73, 95% CI 4.11-18.56), and VACS Index (per 5-point increase OR 1.62, 95% CI 1.43-1.84) were strongly associated with hospitalization. Associations were similar for intensive care. Although significant in unadjusted analyses, associations with comorbid conditions and medications were substantially reduced and, in most cases, no longer significant after adjustment. Conclusions and Relevance: Black race was strongly associated with Covid-19+, but not with hospitalization or intensive care. Among Covid-19+, risk of hospitalization and intensive care may be better characterized by laboratory measures and vital signs than by comorbid conditions or prior medication exposure. Key Points: Question: What are the demographic and clinical characteristics associated with testing positive for coronavirus 2019 (Covid-19+), and among Covid-19+ subsequent hospitalization and intensive care among Veterans in the United States? Findings: In this retrospective cohort study of 2,026,227 Veterans aged 54-75 years and active in care, 585/3,789 (15.4%) tested Covid-19+. Black race was strongly associated with Covid-19+, but not with hospitalization or intensive care. Among Covid-19+, laboratory abnormalities and a summary measure of physiologic injury were strongly associated with hospitalization and intensive care. Meaning: Racial differences in testing positive for Covid-19 may be an underestimate of the general population as racial health disparities in the Veterans Affairs Healthcare System tend to be smaller than in the private sector. Risk of hospitalization and intensive care may be better characterized by laboratory measures and vital signs than by comorbid conditions or prior medication exposure.

One way to address the current crisis in opioid use is to improve our understanding of the biological mechanisms of opioid use disorder (OUD). We completed a primary GWAS of electronic health record-defined OUD in European-ancestry participants in the Million Veteran Program (MVP) sample, which included 8,529 affected subjects and 71,200 opioid-exposed controls. In the MVP alone, there were no genome-wide significant (GWS) associations. We then subjected the MVP and additional OUD GWAS results from the Yale-Penn and SAGE samples to meta-analysis (in total, 10,544 OUD cases and 72,163 opioid-exposed controls). A functional coding variant (rs1799971, encoding Asn40Asp) in OPRM1 (mu opioid receptor gene, the main biological target for opioid drugs) reached GWS (p=1.51×10 ⁻⁸ ); then replicated in two independent samples (each at p−10 . SNP-based heritability of OUD was 11.3%. OUD was genetically correlated with 83 traits, including multiple substance use traits, psychiatric illnesses, cognitive performance, and others. Mendelian Randomization revealed possible causal effects on OUD risk from tobacco smoking, major depression, neuroticism, and cognitive performance. Despite the inclusion of data from the MVP, discovery of a significant association depended on including other purpose-collected samples as well. Recruitment of additional opioid dependent subjects for future studies – especially of non-European ancestry – is a crucial next step.

Background: Veterans with hepatitis C virus (HCV) infection may face geographic obstacles to obtaining treatment. Objective: We studied the influence of region and rural versus urban residence on receipt of direct-acting antiretroviral (DAA) medications for HCV. Subjects: Veterans receiving care within Veterans Affairs Healthcare System born between 1945 and 1965. Research Design: This is a observational study using national electronic health record data. Measures: Receipt of DAAs was defined as ≥1 filled prescription from January 1, 2014 to December 31, 2016. Region (South, Northeast, Midwest, and West) and residence (urban, rural-micropolitan, small rural towns, and isolated rural towns) variables were created using residential zone improvement plan codes and rural-urban commuting area (RUCA) codes. Multivariable models were adjusted for age, race, sex, severity of liver disease, comorbidities, and prior treatment experience. Results: Among 166,353 eligible patients 64,854 received, DAAs. Variation by rural-urban residence depended on region. In unadjusted analyses, receipt varied by rural-urban designations within Midwest, and West regions (PP=0.12). Southern rural small town had the lowest incidence of DAA receipt (40.1%), whereas the incidence was 52.9% in Midwestern isolated rural towns. In adjusted logistic analyses, compared with southern urban residents (the largest single group), southern rural small town residents had the lowest odds ratio, 0.85 (95% confidence interval, 0.75–0.93), and Midwestern residents from isolated and small rural towns had the highest odds (odds ratio, both 1.27) to receive treatment. Conclusions: Substantial geographic variation exists in receipt of curative HCV treatment. Efforts are needed to provide more equitable access to DAAs.