Improving Adherence to Clinical Practice Guidelines for Managing Gastric Intestinal Metaplasia Among Gastroenterologists at a US Academic Institution.

BACKGROUND: Clinical guidelines reserve endoscopic surveillance after a gastric intestinal metaplasia (GIM) diagnosis for high-risk patients. However, it is unclear how closely guidelines are followed in clinical practice. We examined the effectiveness of a standardized protocol for the management of GIM among gastroenterologists at a US hospital. METHODS: This was a preintervention and postintervention study, which included developing a protocol and education of gastroenterologists on GIM management. For the preintervention study, 50 patients with GIM were randomly selected from a histopathology database at the Houston VA Hospital between January 2016 and December 2019. For the postintervention study, we assessed change in GIM management in a cohort of 50 patients with GIM between April 2020 and January 2021 and surveyed 10 gastroenterologists. The durability of the intervention was assessed in a cohort of 50 GIM patients diagnosed between April 2021 and July 2021. RESULTS: In the preintervention cohort, GIM location was specified (antrum and corpus separated) in 11 patients (22%), and Helicobacter pylori testing was recommended in 11 of 26 patients (42%) without previous testing. Gastric mapping biopsies were recommended in 14% and surveillance endoscopy in 2%. In the postintervention cohort, gastric biopsy location was specified in 45 patients (90%, P <0.001) and H. pylori testing was recommended in 26 of 27 patients without prior testing (96%, P <0.001). Because gastric biopsy location was known in 90% of patients ( P <0.001), gastric mapping was not necessary, and surveillance endoscopy was recommended in 42% ( P <0.001). One year after the intervention, all metrics remained elevated compared with the preintervention cohort. CONCLUSIONS: GIM management guidelines are not consistently followed. A protocol for GIM management and education of gastroenterologists increased adherence to H. pylori testing and GIM surveillance recommendations.

An Atlas Characterizing the Shared Genetic Architecture of Inflammatory Bowel Disease with Clinical and Behavioral Traits.

BACKGROUND: Inflammatory bowel disease (IBD) development is a complex, multifactorial process that involves extrinsic and intrinsic factors such as host genetics, the immune system, the gut microbiome, and environmental risks. To help understand the genetic contribution of clinical, behavioral, psychiatric, and diet-related traits, we aim to provide a deep and comprehensive characterization of the shared genetic architecture between IBD and hundreds of potentially related traits. METHODS: Utilizing publicly available summary statistics from a previously published IBD genome-wide association study and hundreds of traits from the United Kingdom BioBank (UKBB), we performed linkage disequilibrium score regression (LDSR) analysis to estimate cross-trait genetic correlations between Crohn's disease (CD), ulcerative colitis (UC), and IBD summary statistics with the UKBB traits of interest. RESULTS: Nominally significant (P < .05) genetic correlations were observed for 181 traits in overall IBD, 239 traits in CD, and 94 traits in UC. We replicate the known association between smoking behavior and CD/UC, namely that current tobacco smoking has a positive genetic correlation with CD (rg = 0.12, P = 4.2 × 10-4), while "ever smoking" has a negative genetic correlation with UC (rg = -0.07, P = .042). Globally, all 3 strata (IBD, CD, and UC) demonstrated increased genetic correlations for psychiatric-related traits related to anxiety and depression. CONCLUSION: The present analysis reveals the shared genetic architecture between multiple traits and IBD, CD, and UC. Understanding the relevance of joint occurrences of IBD with psychiatric diseases may moderate management of these diseases for individuals jointly affected by them.

This study provides an atlas of the genetic correlation between hundreds of United Kingdom Biobank (UKBB) traits with inflammatory bowel disease (IBD), Crohn's disease (CD), and ulcerative colitis (UC). Notable strong correlations are seen between IBD and various psychiatric traits.

Using Natural Language Processing to Automatically Identify Dysplasia in Pathology Reports for Patients With Barrett's Esophagus.

BACKGROUND & AIMS: Identifying dysplasia of Barrett's esophagus (BE) in the electronic medical record (EMR) requires manual abstraction of unstructured data. Natural language processing (NLP) creates structure to unstructured free text. We aimed to develop and validate an NLP algorithm to identify dysplasia in BE patients on histopathology reports with varying report formats in a large integrated EMR system. METHODS: We randomly selected 600 pathology reports for NLP development and 400 reports for validation from patients with suspected BE in the national Veterans Affairs databases. BE and dysplasia were verified by manual review of the pathology reports. We used NLP software (Clinical Language Annotation, Modeling, and Processing Toolkit; Melax Tech, Houston, TX) to develop an algorithm to identify dysplasia using findings. The algorithm performance characteristics were calculated as recall, precision, accuracy, and F-measure. RESULTS: In the development set of 600 patients, 457 patients had confirmed BE (60 with dysplasia). The NLP identified dysplasia with 98.0% accuracy, 91.7% recall, and 93.2% precision, with an F-measure of 92.4%. All 7 patients with confirmed high-grade dysplasia were classified by the algorithm as having dysplasia. Among the 400 patients in the validation cohort, 230 had confirmed BE (39 with dysplasia). Compared with manual review, the NLP algorithm identified dysplasia with 98.7% accuracy, 92.3% recall, and 100.0% precision, with an F-measure of 96.0%. CONCLUSIONS: NLP yielded a high degree of sensitivity and accuracy for identifying dysplasia from diverse types of pathology reports for patients with BE. The application of this algorithm would facilitate research and clinical care in an EMR system with text reports in large data repositories.

Neutrophil-to-Lymphocyte Ratio and Platelet-to-Lymphocyte Ratio as Biomarkers in Axial Spondyloarthritis: Observational Studies From the Program to Understand the Longterm Outcomes in Spondyloarthritis Registry.

OBJECTIVES: This study was conducted to assess the utility of neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) in predicting radiographic sacroiliitis and active disease in axial spondyloarthritis (SpA) and to explore the association between use of a tumor necrosis factor inhibitor (TNFi) and these laboratory values compared with traditional inflammatory markers. METHODS: Observational data from the Program to Understand the Longterm Outcomes in Spondyloarthritis (PULSAR) registry were analyzed. We generated receiver operating characteristic curves to calculate laboratory cutoff values; we used these values in multivariable logistic regression models to identify associations with radiographically confirmed sacroiliitis and active disease. We also used logistic regression to determine the likelihood of elevated laboratory values after initiation of TNFi. RESULTS: Most study participants (n = 354) were White, male, and HLA-B27 positive. NLR (odds ratio [OR] 1.459, P = 0.034), PLR (OR 4.842, P < 0.001), erythrocyte sedimentation rate (OR 4.397, P < 0.001), and C-reactive protein (CRP) level (OR 2.911, P = 0.001) were independent predictors of radiographic sacroiliitis. Models that included PLR with traditional biomarkers performed better than those with traditional biomarkers alone. NLR (OR 6.931, P = 0.002) and CRP (OR 2.678, P = 0.004) were predictors of active disease, but the model that included both NLR and CRP performed better than CRP alone. TNFi use reduced the odds of elevated NLR (OR 0.172, P < 0.001), PLR (OR 0.073, P < 0.001), erythrocyte sedimentation rate (OR 0.319, P < 0.001), and CRP (OR 0.407, P < 0.001), but models that included NLR or PLR and traditional biomarkers performed best. CONCLUSIONS: These findings demonstrate an association between NLR and PLR and sacroiliitis and disease activity, with NLR and PLR showing response after TNFi treatment and adding useful clinical information to established biomarkers, thus perhaps assisting in management of axial SpA.

Comparative Effectiveness of Surveillance Colonoscopy Intervals on Colorectal Cancer Outcomes in a National Cohort of Patients with Inflammatory Bowel Disease.

BACKGROUND & AIMS: Surveillance colonoscopy is recommended to reduce colorectal cancer (CRC)-related morbidity and mortality in patients with inflammatory bowel disease (IBD). The comparative effectiveness of varying colonoscopy intervals on CRC outcomes among patients with IBD is unknown. METHODS: We performed a retrospective cohort study of patients with confirmed CRC within a cohort of 77,824 patients with IBD during 2000 to 2015 in the National Veterans Health Administration. We examined the association between colonoscopy surveillance intervals on CRC stage, treatment, or all-cause and cancer-specific mortality. The interval of colonoscopy prior to CRC diagnosis was categorized as those performed within <1 year, 1 to 3 years, 3 to 5 years, or none within 5 years. RESULTS: Among 566 patients with CRC-IBD, most (69.4%) did not have colonoscopy within 5 years prior to CRC diagnosis, whereas 9.7% had colonoscopy within 1 year prior to diagnosis, 17.7% within 1 to 3 years, and 3.1% between 3 and 5 years. Compared with no surveillance, colonoscopy within 1 year (adjusted odds ratio, 0.40; 95% confidence interval [CI], 0.20-0.82), and 1 to 3 years (adjusted odds ratio, 0.56; 95% CI, 0.32-0.98) were less likely to be diagnosed at late stage. Regardless of IBD type and duration, colonoscopy within 1 year was associated with a lower all-cause mortality (adjusted hazard ratio, 0.56; 95% CI, 0.36-0.88). CONCLUSIONS: In a national cohort of patients with CRC-IBD, colonoscopy within 3 years prior to CRC diagnosis was associated with early tumor stage at diagnosis, and colonoscopy within 1 year was associated with a reduced all-cause mortality compared with no colonoscopy. Our findings support colonoscopy intervals of 1 to 3 years in patients with IBD to reduce late-stage CRC and all-cause mortality.

Association Between Statin Use at the Time of Intra-abdominal Surgery and Postoperative Adhesion-Related Complications and Small-Bowel Obstruction.

Importance: Adhesion-related complications (ARCs), including small-bowel obstruction, are common complications of intra-abdominal surgery. Statins, which have antifibrotic pleiotropic effects, inhibit adhesion formation in murine models but have not been assessed in humans. Objective: To assess whether statin use at the time of intra-abdominal surgery is associated with a reduction in ARCs. Design, Setting, and Participants: These 2 separate retrospective cohort studies (The Health Improvement Network [THIN] and Optum's Clinformatics Data Mart [Optum]) compared adults receiving statins with those not receiving statins at the time of intra-abdominal surgery. Individuals undergoing intra-abdominal surgery from January 1, 1996, to December 31, 2013, in the United Kingdom and from January 1, 2000, to December 31, 2016, in the US were included in the study. Those with obstructive events before surgery or a history of inflammatory bowel disease were excluded. Data analysis was performed from September 1, 2012, to November 24, 2020. Exposure: The primary exposure was statin use at the time of surgery. Main Outcomes and Measures: The primary outcome was ARCs, defined as small-bowel obstruction or need for adhesiolysis, occurring after surgery. Sensitivity analyses included statin use preceding but not concurrent with surgery, fibrate use, and angiotensin-converting enzyme inhibitor use. All analyses were adjusted for age, sex, and conditions associated with microvascular disease, such as hypertension, hyperlipidemia, obesity, and tobacco use; surgical approach and site; and diagnosis of a malignant tumor. Results: A total of 148 601 individuals met the inclusion criteria for THIN (mean [SD] age, 49.6 [17.7] years; 70.1% female) and 1 188 217 for Optum (mean [SD] age, 48.2 [16.4] years; 72.6% female). A total of 2060 participants (1.4%) experienced an ARC in THIN and 54 136 (4.6%) in Optum. Statin use at the time of surgery was associated with decreased risk of ARCs (THIN: adjusted hazard ratio [HR], 0.81; 95% CI, 0.71-0.92; Optum: adjusted HR, 0.92; 95% CI, 0.90-0.95). Similar associations were appreciated between statins and small-bowel obstruction (THIN: adjusted HR, 0.80; 95% CI, 0.70-0.92; Optum: adjusted HR, 0.88; 95% CI, 0.85-0.91). Conclusions and Relevance: This study's findings suggest that, among individuals in 2 separate cohorts undergoing intra-abdominal surgery, statin use may be associated with a reduced risk of postoperative ARCs. Statins may represent an inexpensive, well-tolerated pharmacologic option for preventing ARCs.

Whole-genome sequencing of African Americans implicates differential genetic architecture in inflammatory bowel disease.

Whether or not populations diverge with respect to the genetic contribution to risk of specific complex diseases is relevant to understanding the evolution of susceptibility and origins of health disparities. Here, we describe a large-scale whole-genome sequencing study of inflammatory bowel disease encompassing 1,774 affected individuals and 1,644 healthy control Americans with African ancestry (African Americans). Although no new loci for inflammatory bowel disease are discovered at genome-wide significance levels, we identify numerous instances of differential effect sizes in combination with divergent allele frequencies. For example, the major effect at PTGER4 fine maps to a single credible interval of 22 SNPs corresponding to one of four independent associations at the locus in European ancestry individuals but with an elevated odds ratio for Crohn disease in African Americans. A rare variant aggregate analysis implicates Ca2+-binding neuro-immunomodulator CALB2 in ulcerative colitis. Highly significant overall overlap of common variant risk for inflammatory bowel disease susceptibility between individuals with African and European ancestries was observed, with 41 of 241 previously known lead variants replicated and overall correlations in effect sizes of 0.68 for combined inflammatory bowel disease. Nevertheless, subtle differences influence the performance of polygenic risk scores, and we show that ancestry-appropriate weights significantly improve polygenic prediction in the highest percentiles of risk. The median amount of variance explained per locus remains the same in African and European cohorts, providing evidence for compensation of effect sizes as allele frequencies diverge, as expected under a highly polygenic model of disease.

Development and Validation of an Administrative Codes Algorithm to Identify Abdominal Surgery and Bowel Obstruction in Patients With Inflammatory Bowel Disease.

Background: Validated administrative codes (CPT and ICD) can permit the use of large databases to study diseases and outcomes. The aim of this study was to validate administrative codes for surgery and obstructive complications in patients with inflammatory bowel disease (IBD). Methods: We performed a retrospective study of IBD patients within the Veterans Affairs Health Administration (VA) from 2000 to 2015 with administrative codes for bowel surgery and complications validated by chart review. Positive predictive values (PPVs) and negative predictive value (NPV) were calculated. Results: The PPV for bowel surgery was 96.4%; PPV of obstruction codes for bowel obstruction was 80.5% (95% confidence interval: 69.1%, 89.2%). Conclusions: CPT and ICD codes for abdominal surgery and obstructive complications can be accurately utilized in IBD patients in VA.

Cloning of ground-state intestinal stem cells from endoscopic biopsy samples.

'Adult' or 'somatic' stem cells harbor an intrinsic ability to regenerate tissues. Heterogeneity of such stem cells along the gastrointestinal tract yields the known segmental specificity of this organ and may contribute to the pathology of certain enteric conditions. Here we detail technology for the generation of 'libraries' of clonogenic cells from 1-mm-diamter endoscopic biopsy samples from the human gastrointestinal tract. Each of the 150-300 independent clones in a typical stem cell library can be clonally expanded to billions of cells in a few weeks while maintaining genomic stability and the ability to undergo multipotent differentiation to the specific epithelia from which the sample originated. The key to this methodology is the intrinsic immortality of normal intestinal stem cells (ISCs) and culture systems that maintain them as highly immature, ground-state ISCs marked by a single-cell clonogenicity of 70% and a corresponding 250-fold proliferative advantage over spheroid technologies. Clonal approaches such as this enhance the resolution of molecular genetics, make genome editing easier, and may be useful in regenerative medicine, unravelling heterogeneity in disease, and facilitating drug discovery.

Rates of Adverse IBD-Related Outcomes for Patients With IBD and Concomitant Prostate Cancer Treated With Radiation Therapy.

BACKGROUND: Patients with inflammatory bowel disease (IBD) may be at higher risk for complications from radiation treatment for prostate cancer. However, available data are limited, and controversy remains regarding the best treatment approach for IBD patients who develop prostate cancer. METHODS: A retrospective cohort study across 4 Department of Veterans Affairs hospital systems. Patients with established IBD who were diagnosed and treated for prostate cancer between 1996-2015 were included. We assessed for flares of IBD, IBD-related hospitalizations, and IBD-related surgeries within 6, 12, and 24 months of cancer diagnosis and survival at 1, 2, and 5 years. Flares of IBD were those documented as such by the treating physician, and treatment changed accordingly. RESULTS: One hundred patients with IBD and prostate cancer were identified. Forty-seven were treated with either treatment with external beam radiation or brachytherapy, and 53 were treated with nonradiation modalities. Comparing cohorts with or without radiation treatment, there were no differences in baseline IBD characteristics, Charlson comorbidity index, or prostate cancer stage. Inflammatory bowel disease flares were 2-fold higher for radiation-treated patients within 6 months (10.6% vs 5.7%) and 6-12 months (4.3% vs 1.9%) after cancer diagnosis. On multiple logistic regression analysis, radiation treatment (adjusted odds ratio, 4.82; 95% confidence interval, 1.15-20.26) was a significant predictor of flares. However, rates of IBD-related hospitalizations or surgeries were not significantly different. CONCLUSIONS: In this retrospective, multicenter study, 2-fold higher rates of flare were found within the first year after prostate cancer diagnosis for patients treated with radiation, but there were no differences in IBD-related hospitalizations or surgeries. Although patients should be counseled of these risks, avoidance of radiation therapy in IBD patients with prostate cancer is likely not necessary.

Association Between Inflammatory Bowel Disease and Colorectal Cancer Stage of Disease and Survival.

BACKGROUND: Inflammatory bowel disease (IBD) is associated with an increased risk of colorectal cancer (CRC). However, there are few data comparing outcomes between IBD and non-IBD-associated CRC. METHODS: Retrospective cohort study of patients with CRC identified from the Veteran Affairs (VA) Central Cancer Registry from 1998 to 2012 linked to national VA administrative claims to identify patients with IBD using a previously validated algorithm. The association between IBD status and stage of disease and overall risk of death were evaluated using multivariable logistic and Cox regression, respectively. RESULTS: Among 34,570 CRC patients, 217 had IBD. IBD patients were significantly younger for both colon and rectal cancer. IBD patients who developed rectal cancer were significantly more likely to present with locally advanced or metastatic disease (P = 0.007), but there was no difference in stage among patients with colon cancer. This difference persisted after multivariable adjustment (overall-odds ratio [OR] 1.40, 95% confidence interval [1.03-1.90]; colon-OR 1.22 [0.84-1.78]; rectum-OR 2.04 [1.22-3.40]). Total colectomy was more commonly performed among IBD patients. Overall, IBD was associated with a 52% increased risk of death (hazard ratio 1.52 [1.21-1.91]). CONCLUSIONS: Although IBD is associated with more advanced stage at diagnosis for rectal cancer, it is associated with a worse survival primarily in patients with colon cancer. Further work is needed to better understand the reason for these observed differences between IBD and non-IBD patients and to better delineate the impact of endoscopic surveillance on CRC care and outcomes in IBD patients.

The Incidence and Prevalence of Anxiety, Depression, and Post-traumatic Stress Disorder in a National Cohort of US Veterans With Inflammatory Bowel Disease.

BACKGROUND: Patients with inflammatory bowel disease (IBD) are more susceptible to mental health problems than the general population; however, temporal trends in psychiatric diagnoses' incidence or prevalence in the United States are lacking. We sought to identify these trends among patients with IBD using national Veterans Heath Administration data. METHODS: We ascertained the presence of anxiety, depression, or posttraumatic stress disorder among veterans with IBD (ulcerative colitis or Crohn's disease) during fiscal years 2000-2015. Patients with prior anxiety, depression, or posttraumatic stress disorder before their first Veterans Health Administration IBD encounter were excluded to form the study cohort. We calculated annual prevalence, incidence rates, and age standardized and stratified by gender using a direct standardization method. RESULTS: We identified 60,086 IBD patients (93.9% male). The prevalence of anxiety, depression, and/or posttraumatic stress disorder increased from 10.8 per 100 with IBD in 2001 to 38 per 100 with IBD in 2015; 19,595 (32.6%) patients had a new anxiety, depression, and/or posttraumatic stress disorder diagnosis during the study period. The annual incidence rates of these mental health problems went from 6.1 per 100 with IBD in 2001 to 3.6 per 100 in 2015. This trend was largely driven by decline in depression. CONCLUSIONS: The prevalence of anxiety, depression, and posttraumatic stress disorder is high among US veterans with IBD and increasing, given the chronicity of IBD and psychological diagnoses. Incidence, particularly depression, appears to be declining. Confirmation and reasons for this encouraging trend are needed.

The Association of Medications and Vaccination with Risk of Pneumonia in Inflammatory Bowel Disease.

BACKGROUND: Patients with inflammatory bowel disease (IBD) are at increased risk for pneumonia, and corticosteroids are reported to amplify this risk. Less is known about the impact of corticosteroid-sparing IBD therapies on pneumonia risk or the efficacy of pneumococcal vaccination in reducing all-cause pneumonia in real-world IBD cohorts. METHODS: We performed a population-based study using an established Veterans Health Administration cohort of 29,957 IBD patients. We identified all patients who developed bacterial pneumonia. Cox survival analysis was used to determine the association of corticosteroids at study entry and as a time-varying covariate, corticosteroid-sparing agents (immunomodulators and antitumor necrosis-alpha [TNF] inhibitors), and pneumococcal vaccination with the development of all-cause pneumonia. RESULTS: Patients with IBD who received corticosteroids had a greater risk of pneumonia when controlling for age, gender, and comorbidities (hazard ratio [HR] 2.21; 95% confidence interval [CI], 1.90-2.57 for prior use; HR = 3.42; 95% CI, 2.92-4.01 for use during follow-up). Anti-TNF inhibitors (HR 1.52; 95% CI, 1.02-2.26), but not immunomodulators (HR 0.91; 95% CI, 0.77-1.07), were associated with a small increase in pneumonia. A history of pneumonia was strongly associated with subsequent pneumonia (HR = 4.41; 95% CI, 3.70-5.27). Less than 15% of patients were vaccinated against pneumococcus, and this was not associated with a reduced risk of pneumonia (HR = 1.02; 95% CI, 0.80-1.30) in this cohort. CONCLUSION: In a large US cohort, corticosteroids were confirmed to increase pneumonia risk. Tumor necrosis-alpha inhibitors were associated with a smaller increase in the risk of pneumonia. Surprisingly, pneumococcal vaccination did not reduce all-cause pneumonia in this population, though few patients were vaccinated.

Unlimited expansion of intestinal stem cells from a wide range of ages.

The recent technical advance in cloning and culturing ground-state intestinal stem cells (ISC) provides us an opportunity of accurate assessment of age-related impact on the function of highly proliferative intestinal stem cells. Our ability of indefinitely and robustly expanding single-stem-cell derived pedigrees in vitro allows us to study intestinal stem cells at the clonal level. Interestingly, comparable number of ISC clones was yielded from 1mm endoscopic biopsy of all donors despite the age. They were passaged in vitro as pedigrees and expanded to 1 billion cells in approximately sixty days without changes in stemness demonstrated by clonogenicity and multipotency. Therefore, our study shows that ISCs from a wide range of ages can be cloned and expanded to unlimited number in vitro with similar efficiency and stability. These patient-derived ISCs harbor intrinsic immortality and are ideal for autologous transplantation, supporting the promise of adult-stem-cell based personalized medicine.

Improving Anemia in Inflammatory Bowel Disease: Impact of the Anemia Care Pathway.

BACKGROUND: Anemia is a common complication of inflammatory bowel disease (IBD). Despite existing guidelines for anemia in IBD, it is frequently under-treated and the prevalence of anemia has remained high. To address this gap, the Crohn's and Colitis Foundation developed the Anemia Care Pathway (ACP). AIMS: To implement the ACP in a managed care setting and identify where it improves practice habits and where barriers remain. METHODS: The ACP was implemented from July 2016 through June 2017 and retrospectively studied. Run charts were used to identify shifts in iron deficiency screening and treatment as well as anemia prevalence. Results were compared to those of other providers in the same center not using the ACP. RESULTS: 640 IBD encounters were studied. In the ACP clinic (n = 213), anemics received iron therapy in only 30% of encounters at baseline but improved to 80%. Concurrently, anemia prevalence decreased from 48 to 25%. Screening for iron deficiency, however, did not improve. No shifts were seen in the non-ACP clinics (n = 427) across the same period despite awareness of the ACP and other guidelines. CONCLUSIONS: Across 1 year, we observed gaps in the screening and treatment of anemia in IBD. Although screening rates did not improve, the ACP appeared to reduce missed opportunities for iron therapy by about half. Most importantly, this was associated with an overall decrease in anemia prevalence. Future refinements to the ACP should be focused on enhanced screening and follow-up.

Hepatitis B Virus Screening and Reactivation in a National VA Cohort of Patients with Inflammatory Bowel Disease Treated with Tumor Necrosis Factor Antagonists.

BACKGROUND: Practice guidelines recommend screening for hepatitis B virus (HBV) infection prior to initiating treatment of inflammatory bowel disease (IBD) with anti-tumor necrosis factor (anti-TNF) therapy. However, the adherence to these screening guidelines and the clinical outcomes of HBV reactivation following anti-TNF use are not well known. METHODS: This is a retrospective cohort study using the Veterans Health Administration datasets for IBD patients with filled prescriptions for anti-TNFs from 2003 to 2011. Laboratory testing was used to define HBV screening status in the 12 months preceding anti-TNF initiation. Logistic regression models were used to identify predictors of HBV screening. Cases of potential HBV reactivation were identified using ICD-9 codes for HBV infection or acute liver failure or by medications used for HBV infection treatment, and manually reviewed for verification. RESULTS: We identified 3357 IBD patients with filled prescriptions for anti-TNF medications. The HBV testing prior to anti-TNF initiation was 8.1% in 2003 and increased to 43.2% by 2011, with an overall rate of 23.7%. In multivariate analysis, African-American race, facilities with a higher volume of IBD patients, and facilities with an academic affiliation were associated with a higher probability of HBV screening. We did not identify a single case of confirmed clinically relevant HBV reactivation after anti-TNF initiation during 7210 patient-years of medication use. CONCLUSIONS: HBV screening rates prior to anti-TNF initiation are low among IBD patients, but have increased over time. Despite low rates of screening, clinically significant HBV reactivation after anti-TNF initiation in this US cohort was nonexistent.