Major Gastrointestinal Bleeding Research Articles

The initial high-dose versus maintenance-dose anticoagulation therapy with direct oral anticoagulants for cancer-associated venous thromboembolism: from the COMMAND VTE Registry-2

Abstract Background/Introduction Initial high-dose anticoagulation therapy with rivaroxaban and apixaban has been a standard treatment for venous thromboembolism (VTE), although there could be concerns of an increased risk of bleeding events especially among high bleeding-risk patients including those with active cancer. Purpose The present study aimed to evaluate the clinical outcome of initial high-dose anticoagulation therapy comparing to maintenance-dose anticoagulation therapy in patients with cancer-associated VTE using propensity score-matching analysis. Methods The COMMAND VTE Registry-2 is a multicenter registry enrolling 5197 consecutive acute symptomatic VTE patients among 31 centers in Japan between January 2015 and August 2020. Among 1507 patients with cancer-associated VTE, we evaluated 180-day clinical outcomes before discontinuation of anticoagulation therapy using a 1:1 propensity score-matching model with 21 risk-adjusting variables Results After the propensity score-matching, we enrolled 324 patients with initial high-dose anticoagulation therapy and 324 patients with initial maintenance dose anticoagulation therapy. Of patients with initial high-dose anticoagulation therapy, rivaroxaban and apixaban were administered in 198 and 126 patients, respectively. Of those with initial maintenance-dose anticoagulation therapy, rivaroxaban, apixaban, and edoxaban were administered in 34, 46 and 244 patients, respectively. The median durations of initial high-dose anticoagulation therapy were 18 [IQR: 15-21] days for rivaroxaban and 7 [IQR: 7-7] days for apixaban. In the current study population, the mean age was 67±12 years, 346 were women, and the mean body weight was 58±12 kg. There was no significant difference in the distribution of gastrointestinal cancer such as stomach and colorectal cancer between the 2 groups (4.6% vs. 4.9%, P=1.0, 8.3% vs. 11.4%, P=0.22). The cumulative 180-day incidence of discontinuation of anticoagulation was not significantly different between the 2 groups (27.8% vs. 30.5%, P=0.50). There were no significant differences in the cumulative 180-day incidences of recurrent VTE (3.1% vs. 1.0%, P=0.08), nor major bleeding (8.1% vs. 7.0%, P=0.66), nor all-cause death (25.1% vs. 21.6%, P=0.33) between the 2 groups. There were also no significant differences in the cumulative 180-day incidences of all clinically relevant bleeding (14.9% vs. 13.3%, P=0.72), gastrointestinal bleeding (8.4% vs. 5.4%, P=0.15), nor major gastrointestinal bleeding (5.4% vs. 2.7%, P=0.10). Conclusions There was no signal of an increased risk of recurrent VTE in the initial maintenance-dose anticoagulation therapy. Considering a numerically slightly higher incidence of gastrointestinal bleeding in the initial high-dose anticoagulation therapy for cancer-associated VTE, the initial maintenance-dose anticoagulation therapy could be a potential treatment option for selected patients including patients at a high risk of gastrointestinal bleeding.Study flow chartResults

Impact of statins on incidence of gastrointestinal bleeding events among patients with continuous-flow left ventricular assist devices.

Patients with continuous flow left ventricular assist devices (CF-LVADs) are at increased risk of gastrointestinal bleeding (GIB). Statins are commonly prescribed in LVAD patients for cardiovascular disease prevention. However, their impact on GIB events is controversial. Importantly, literature regarding statins impact on GIB in CF-LVAD patients is lacking. A single-center, retrospective review of adult patients who underwent CF-LVAD implantation between May 2016 and January 2020 was performed. Patients were categorized based on statin use throughout the study period. The primary outcome was the composite of arteriovenous malformation confirmed GIB and major GIB events for up to 1-year post-LVAD implantation. Of 123 patients included in the final analysis, 66 (54%) received statin therapy during the study period. No difference was observed in the primary outcome between the statin and control groups (RR: 1.73; 95% CI: 0.75-3.98; p=0.20). Multivariable Cox regression revealed that older age and higher baseline creatinine were associated with an increased risk of GIB within 1-year of CF-LVAD implantation. Among patients with CF-LVADs, there was no significant difference in the incidence of major GIB events associated with the use of statin therapy. Further studies are needed to assess whether a true association exists.

Prognosis of major bleeding based on residual variables and machine learning for critical patients with upper gastrointestinal bleeding: A multicenter study

BackgroundUpper gastrointestinal bleeding (UGIB) is a significant cause of morbidity and mortality worldwide. This study investigates the use of residual variables and machine learning (ML) models for predicting major bleeding in patients with severe UGIB after their first intensive care unit (ICU) admission. MethodsThe Medical Information Mart for Intensive Care IV and eICU databases were used. Conventional ML and long short-term memory models were constructed using pre-ICU and ICU admission day data to predict the recurrence of major gastrointestinal bleeding. In the models, residual data were utilized by subtracting the normal range from the test result. The models included eight algorithms. Shapley additive explanations and saliency maps were used for feature interpretability. ResultsTwenty-five ML models were developed using data from 2604 patients. The light gradient-boosting machine algorithm model using pre-ICU admission residual data outperformed other models that used test results directly, with an AUC of 0.96. The key factors included aspartate aminotransferase, blood urea nitrogen, albumin, length of ICU admission, and respiratory rate. ConclusionsML models using residuals improved the accuracy and interpretability in predicting major bleeding during ICU admission in patients with UGIB. These interpretable features may facilitate the early identification and management of high-risk patients, thereby improving hemodynamic stability and outcomes.

S3850 Acute severe ulcerative colitis with major acute gastrointestinal hemorrhage

S3850 Acute severe ulcerative colitis with major acute gastrointestinal hemorrhage

Impact of proton pump inhibitor use on clinical outcomes in East Asian patients receiving clopidogrel following drug-eluting stent implantation

BackgroundConcomitant use of clopidogrel and proton pump inhibitor (PPI) is common, but PPI may reduce the antiplatelet effects of clopidogrel in patients undergoing percutaneous coronary intervention (PCI). We evaluated the impact of PPI use on clinical outcomes in post-PCI patients, by incorporating P2Y12 reaction unit (PRU) and CYP2C19 genotyping results.MethodsFrom a multicenter registry of patients who underwent PCI with drug-eluting stent implantation and received clopidogrel-based dual antiplatelet therapy (DAPT), patients who were prescribed a PPI at the time of PCI (PPI users) were compared to those who were not (non-users). The primary outcome included all-cause death, myocardial infarction, stent thrombosis, or cerebrovascular accident at 12 months. Major bleeding (Bleeding Academic Research Consortium [BARC] types 3–5) and gastrointestinal (GI) bleeding (BARC types 3–5) were important secondary outcomes. The adjusted outcomes were compared using a 1:1 propensity-score (PS) matching and competing risk analysis.ResultsOf 13,160 patients, 2,235 (17.0%) were prescribed PPI, with an average age of 65.4 years. PPI users had higher on-treatment PRU levels than non-users. After PS matching, the primary outcome occurred in 51 patients who were PPI users (cumulative incidence, 4.7%) and 41 patients who were non-users (cumulative incidence, 3.7%; log-rank p = 0.27). In carriers of both CYP2C19 loss-of-function alleles, PPI use was linked to an increased risk of the primary outcome (hazard ratio, 3.22; 95% confidence interval, 1.18–8.78). The incidence of major bleeding and GI bleeding (BARC types 3–5) was comparable between PPI users and non-users in the PS-matched cohort.ConclusionsIn post-PCI patients receiving clopidogrel-based DAPT, PPI use was not linked to an increased risk of adverse cardiac and cerebrovascular events, but there was a small but significant increase in on-treatment PRU. Future research using a more individualized approach would further elucidate these interactions and guide evidence-based clinical practices.

Comparative Effectiveness and Safety of Apixaban, Rivaroxaban, and Warfarin in Patients With Cirrhosis and Atrial Fibrillation : A Nationwide Cohort Study.

Apixaban, rivaroxaban, and warfarin have shown benefit for preventing major ischemic events, albeit with increased bleeding risk, among patients in the general population with atrial fibrillation (AF). However, data are scarce in patients with cirrhosis and AF. To compare the effectiveness and safety of apixaban versus rivaroxaban and versus warfarin in patients with cirrhosis and AF. Population-based cohort study. Two U.S. claims data sets (Medicare and Optum's de-identified Clinformatics Data Mart Database [2013 to 2022]). 1:1 propensity score (PS)-matched patients with cirrhosis and nonvalvular AF initiating use of apixaban, rivaroxaban, or warfarin. Primary outcomes included ischemic stroke or systemic embolism and major hemorrhage (intracranial hemorrhage or major gastrointestinal bleeding). Database-specific and pooled PS-matched rate differences (RDs) per 1000 person-years (PY) and Cox proportional hazard ratios (HRs) with 95% CIs were estimated, controlling for 104 preexposure covariates. Rivaroxaban initiators had significantly higher rates of major hemorrhagic events than apixaban initiators (RD, 33.1 per 1000 PY [95% CI, 12.9 to 53.2 per 1000 PY]; HR, 1.47 [CI, 1.11 to 1.94]) but no significant differences in rates of ischemic events or death. Consistently higher rates of major hemorrhage were found with rivaroxaban across subgroup and sensitivity analyses. Warfarin initiators also had significantly higher rates of major hemorrhage than apixaban initiators (RD, 26.1 per 1000 PY [CI, 6.8 to 45.3 per 1000 PY]; HR, 1.38 [CI, 1.03 to 1.84]), particularly hemorrhagic stroke (RD, 9.7 per 1000 PY [CI, 2.2 to 17.2 per 1000 PY]; HR, 2.85 [CI, 1.24 to 6.59]). Nonrandomized treatment selection. Among patients with cirrhosis and nonvalvular AF, initiators of rivaroxaban versus apixaban had significantly higher rates of major hemorrhage and similar rates of ischemic events and death. Initiation of warfarin versus apixaban also contributed to significantly higher rates of major hemorrhagic events, including hemorrhagic stroke. National Institutes of Health.

Incidence and predictors of major gastrointestinal bleeding in patients on aspirin, low-dose rivaroxaban, or the combination: Secondary analysis of the COMPASS randomised controlled trial.

The incidence of major gastrointestinal bleeding (GIB) in patients on low-dose direct-acting oral anticoagulants (DOACs) is relatively unknown. Estimates from randomised controlled trials (RCTs) are lacking. To assess GIB incidence and predictors from RCT data of patients on aspirin, low-dose rivaroxaban, or both. This was a secondary analysis of RCT data wherein patients received aspirin 100 mg daily and rivaroxaban 2.5 mg b.d., aspirin alone, or rivaroxaban 5 mg b.d. Patients were followed from 2013 to 2016 at 602 centres. Outcomes included overall, upper, and lower GIB. We employed multivariable logistic regression to yield odds ratios (ORs) and 95% confidence intervals for potential exposures. Among 27,395 patients, the annual incidence of GIB on rivaroxaban 2.5 mg b.d. with aspirin was 801.7 per 100,000 compared with 372.3 in 100,000 for aspirin. Age (OR 4.16, 2.53-6.82 for ≥75 vs. 55-64), peptic ulcer disease (PUD, OR 1.57, 1.01-2.44), liver disease (OR 2.09, 1.01-4.33), hypertension (OR 1.42, 1.04-1.94), and smoking (OR 1.85, 1.26-2.73) were associated with overall GIB. Kidney disease (OR 1.68, 1.12-2.51) was significantly associated with upper GIB, whereas diverticular disease (OR 3.75, 1.88-7.49) was associated with lower GIB. Addition of rivaroxaban to aspirin was associated more with lower GIB (OR 2.82, 1.64-4.84) than upper GIB (OR 1.86, 1.18-2.92). We established incidences and identified risk factors for GIB in users of low-dose DOACs. Novel risk factors included current or former smoking and diverticulosis. Future studies should aim to validate these risk factors.

One-year effectiveness and safety outcomes of edoxaban treatment in Chinese patients with atrial fibrillation: First snapshot of more than 4,800 patients from the ETNA-AF-China study

Abstract Background Direct oral anticoagulants (DOACs) have become the first-line therapy for ischaemic stroke prevention in atrial fibrillation (AF) patients. Data on the effectiveness and safety of single DOAC in large Chinese populations are scarce. Purpose We firstly present the one-year outcome data of edoxaban treatment in 5001 Chinese AF patients. Methods This is a multi-centre, prospective, observational study, ETNA-AF-China, conducted in 89 centres from four economic regions in Mainland of China with a follow-up of two years. Primary endpoint of safety [bleeding events including intracranial hemorrhage (ICH), all-cause and cardiovascular (CV) mortality] and efficacy endpoints [stroke, systemic embolic events (SEE), transient ischemic attack (TIA)] were adjudicated. Annualised event rates and Kaplan­Meier (KM) survival curves are given. Results A total of 4822 patients (57.1% male) using edoxaban (60 mg OD: n=2614, 30 mg OD: n=2208) who completed one-year follow-up were included in the full analysis set. The mean (SD) age of the overall patient population was 70.3 (9.5) years, CHA2DS2-VASc and HAS-BLED scores were 2.9 (1.4), 1.7 (1.0), with creatinine clearance (CrCl) of 71.2 (27.7) mL/min. Patients receiving 30 mg OD edoxaban at baseline were older (73.4 vs 67.7 years), with higher CHA2DS2-VASc score (3.3 vs 2.6), larger percentage of frail (9.9% vs 3.4%), and higher renal impairment (defined as CrCl ≤80 mL/min, 70.3% vs 42.9%). Annualised rates for all-cause and cardiovascular death in the overall population were very low with 2.22%/year and 0.41%/year, respectively. (Figure 1) The death rates were nearly three times lower in those receiving standard dose (60 mg) than reduction dose (30 mg) of edoxaban. Annualised event rates for all stroke/SEE (1.03%/year) and ischemic stroke (0.60%/year) were similar between two dose groups. Overall, annualised rates for major bleeding (1.03%/year), ICH (0.18%/year), major gastrointestinal (GI) bleeding (0.48%/year) events were relatively low, and those on 60 mg dose experienced less above bleeding events. Cumulative survival analysis demonstrated a slow increase in time-to-first event curve of all-cause death; and from baseline to 1-year follow-up, significant lower events of all-cause death (log-rank p<0.001), major bleeding (p=0.002) in 60 mg vs 30 mg edoxaban groups. (Figure 2). Conclusion Low incidences of major bleeding, notably ICH, major GI bleeding, and CV death were observed in unselected 4822 patients with AF during 1-year of edoxaban treatment. These findings confirm the effectiveness and safety of routine edoxaban use in China, consistent with other countries, and reinforce the results of the ENGAGE AF-TIMI 48 trial.Figure 1Figure 2

#688 Major gastrointestinal bleeding in dialysis: influence of age, sex, race & comorbidities

Abstract Background and Aims Gastrointestinal bleeding (GIB) is considered the most common type of bleeding event in the dialysis population [1]. However, studies to date are small and not representative of the dialysis population, and the influence of patient characteristics has not been considered. We used a nationally representative sample of dialysis patients treated in the United States (US) to characterize the rates of major GIB episodes requiring hospitalization overall and by age, sex, race, and history of GIB comorbidity. Method We used data from a kidney care network from Jan 2018 through Mar 2021. We included data from adult dialysis patients (age ≥18 years) who were treated with dialysis for at least 30 days. We excluded patients who started dialysis on or after Jan 2021 to provide a three-month minimum follow up time for outcomes to occur. GIB hospitalizations were identified from international classification of diseases (ICD) diagnosis codes recorded as the primary, secondary, or tertiary discharge reason for hospitalization. ICD clusters defining GIB hospitalizations and lesion location were based on the US Healthcare Cost and Utilization Project [2]. We calculated proportion of patients with one or more GIB hospitalization, and the proportion of GIB observations per patient during the 3.25-year period by patient characteristics (GIB comorbidity, sex, age, race). Results Among 366,839 adult dialysis patients, 6.8% (n = 25,057) experienced one or more GIB hospitalization during the 3.25-year period. In total, there were 36,791 GIB hospitalization observations with 73.5% (n = 18,422) of patients with one GIB hospitalization, 16.8% (n = 4208) with two GIB hospitalizations, and 9.7% (n = 2,427) with three or more GIB hospitalizations. The lesion location was unspecified in diagnosis codes for 64.7% (n = 23,576) of GIB hospitalization observations. Among GIB hospitalization observations with a recorded lesion location, 60.3% (n = 7,968) were an upper GIB and 39.7% (n = 5,247) were a lower GIB. A baseline history of a GIB comorbidity was associated with a 2.9-fold higher rate for the occurrence of one or more GIB hospitalization in a unique patient, and a 3.5-fold higher rate of a GIB hospitalization event considering all observations (Fig. 1A). GIB hospitalization rates were relatively consistent between females and males on both a patient- and observation-level (Fig. 1B). There were positive increases in GIB hospitalization rates with older age categories, with about a 2-fold higher rate among those with an age ≥75 years compared to an age 18-44 years on both a patient- and observation-level (Fig. 2A). GIB hospitalization rates were relatively consistent for race groups, albeit there may be a trend for slightly higher rates among those with a black race, in particular on an observation level that accounts for multiple events per patient (Fig. 2B). Conclusion Major GIB events requiring hospitalization affect about 7% of dialysis patients. It appears about 60% of GIB hospitalizations were for an upper GIB, and about 40% were for a lower GIB. Patients who experienced one GIB hospitalization commonly had multiple GIB events, with more than 25% having two or more GIB hospitalizations during the observation period. Older age and a history of a baseline GIB comorbidity were associated with higher GIB hospitalization rates. Biological sex and race did not appear to be associated to GIB hospitalization rates. Ongoing analysis of GIB incidence accounting for person-years at risk is needed to confirm these observations.

#2067 Prediction of gastrointestinal bleeding hospitalization risk in hemodialysis using machine learning techniques

Abstract Background and Aims INitiativeS on advancing Patients’ outcomes In REnal disease (INSPIRE) is an academia and industry collaboration set forth to identify critical investigations needed to advance the practice of medicine in nephrology. Gastrointestinal bleeding (GIB) is one of the most common types of bleeding events in the kidney dialysis population [1]. We aimed to develop a model to predict GIB hospitalization risk in a hemodialysis (HD) patient within 180 days. We evaluated advanced machine learning algorithm (XGBoost) and compared it to traditional machine learning algorithm (logistic regression) modeling techniques. Method We used data from a kidney care network from 2017 through 2020. We included data from adult dialysis patients (age ≥18 years). GIB related hospitalization was defined based on international classification of diseases (ICD) diagnosis codes recorded as the primary, secondary, or tertiary discharge reason for hospitalization. Two distinct models were created using XGBoost and logistic regression algorithms and using the same dataset. Both models were evaluated using metrics such as area under the receiver operating curve (AUROC), accuracy, sensitivity, and specificity. Missing data was imputed using mean for quantitative data and mode for qualitative data. The dataset then was randomly divided into 60% training, 20% validation and 20% test dataset. The test data, comprising unseen patients and data was used to evaluate the performance of the model. This means that the model had never encountered the test data during its learning phase, which included training the model and then validating the model. Results The incidence of 180-day GIB hospitalization was 1.12% in the HD population (n = 5 116 with GIB hospitalization/ n = 451 653 without GIB hospitalization), and consistent in the unseen test dataset (n = 465 with GIB hospitalization/ n = 38586 without GIB hospitalization). The XGBoost model showed higher predictive performance compared to logistic regression (Table). The AUROC was 0.72 (95% confidence interval (CI) 0.69, 0.74) for the XGBoost model. In comparison, the AUROC was 0.615 (95% CI 0.60, 0.64) for the logistic regression model. Specificity was 67% versus 58% for the XGBoost model versus logistic regression model respectively. However, sensitivity for both the models was 65%. The top predictors for major GIB were consistent in both models for many factors, yet some factors showed different importance on outcome prediction (Fig. 1). Higher risk of GIB hospitalization was associated with older age, lower ferritin levels, and recent all-cause hospitalizations in both models. The XGBoost showed high importance on outcome prediction for lower hemoglobin and higher serum 25 hydroxy (25OH) vitamin D values, and the logistic regression model showed high importance for higher amounts of saline delivered during an HD treatment and lower intact parathyroid hormone (iPTH) levels. Conclusion We found advanced machine learning prediction modeling (XGBoost) appears suitable for identifying a HD patient at risk for a GIB hospitalization in the next 180 days, and outperforms traditional machine learning (logistic regression) modeling techniques. Although both models showed identical sensitivity, the XGBoost model had higher specificity. Prospective testing is needed to confirm the model's performance. The association between bone mineral metabolism markers and GIB hospitalization risk is unexpected and warrants further investigation.

Dual Antithrombotic Therapy versus Anticoagulant Monotherapy for Major Adverse Limb Events in Patients with Concomitant Lower Extremity Arterial Disease and Atrial Fibrillation: A Propensity Score Weighted Analysis

Patients with symptomatic lower extremity arterial disease (LEAD) are recommended to receive antiplatelet therapy, while direct oral anticoagulants (DOACs) are standard for stroke prevention in patients with atrial fibrillation (AF). For patients with concomitant LEAD and AF, data comparing dual antithrombotic therapy (an antiplatelet agent used in conjunction with a DOAC) vs. DOAC monotherapy are scarce. This retrospective cohort study, based on data from the Taiwan National Health Insurance Research Database, aimed to compare the efficacy and safety of these antithrombotic strategies. Patients with AF who underwent revascularisation for LEAD between 2012 - 2020 and received any DOAC within 30 days of discharge were included. Patients were grouped by antiplatelet agent exposure into the dual antithrombotic therapy and DOAC monotherapy groups. Inverse probability of treatment weighting was used to mitigate selection bias. Major adverse limb events (MALEs), ischaemic stroke or systemic embolism, and bleeding outcomes were compared. Patients were followed until the occurrence of any study outcome, death, or up to two years. A total of 1 470 patients were identified, with 736 in the dual antithrombotic therapy group and 734 in the DOAC monotherapy group. Among them, 1 346 patients received endovascular therapy as the index revascularisation procedure and 124 underwent bypass surgery. At two years, dual antithrombotic therapy was associated with a higher risk of MALEs than DOAC monotherapy (subdistribution hazard ratio [SHR] 1.34, 95% confidence interval [CI] 1.15 - 1.56), primarily driven by increased repeat revascularisation. Dual antithrombotic therapy was also associated with a higher risk of major bleeding (SHR 1.43, 95% CI 1.05 - 1.94) and gastrointestinal bleeding (SHR 2.17, 95% CI 1.42 - 3.33) than DOAC monotherapy. In patients with concomitant LEAD and AF who underwent peripheral revascularisation, DOAC monotherapy was associated with a lower risk of MALEs and bleeding events than dual antithrombotic therapy.

Long-term effectiveness and safety of edoxaban in patients with atrial fibrillation: 4-year data from the ETNA-AF-Europe study

BackgroundTo assess long-term effectiveness and safety of edoxaban in Europe. Methods and resultsETNA-AF-Europe, a prospective, multinational, multi-centre, post-authorisation, observational study was conducted in agreement with the European Medicines Agency. The primary and secondary objectives assessed real-world safety (including bleeding and deaths) and effectiveness (including stroke, systemic embolic events and clinical edoxaban use), respectively.Median (interquartile range) age of the 13,164 patients was 75.0 (68.0–80.0) years; CHA2DS2-VASc and HAS-BLED scores were 3.0 (2.0–4.0) and 2.0 (1.0–2.0), respectively. Follow-up duration was 3.98 (3.21–4.05) years. Patients on edoxaban 30 mg (n = 3042) at baseline were older (80.0 vs 73.0 years), more likely assessed as frail by investigators (27.0% vs 6.6%) and had more comorbidities than those on edoxaban 60 mg (n = 9617; missing dosing information for n = 505). Annualised event rates of all-cause and cardiovascular death in the overall population, edoxaban 60 mg and edoxaban 30 mg groups were 4.1%, 2.8% and 8.4%, and 1.0%, 0.7% and 2.0%, respectively. Annualised rates of stroke were relatively constant throughout the follow-up, transient ischaemic attack and systemic embolism were < 1% in the overall population. Rates of any major and major gastrointestinal bleeding were low, with slightly higher rates for edoxaban 30 vs 60 mg group. Intracranial haemorrhage was uncommon (0.2%). ConclusionsIn European patients with AF, long-term therapy with edoxaban is associated with low and relatively constant annualised rates of stroke and major bleeding. Differences in outcomes between the two approved doses are attributable to differences in clinical characteristics.

Development and Application of an Attribute-Based Taxonomy on the Benefits of Oral Anticoagulant Switching in Atrial Fibrillation: A Delphi Study.

Patients with atrial fibrillation (AF) often switch between oral anticoagulants (OACs). It can be hard to know why a patient has switched outside of a clinical setting. Medication attribute comparisons can suggest benefits. Consensus on terms and definitions is required for inferring OAC switch benefits. The objectives of the study were to generate consensus on a taxonomy of the potential benefits of OAC switching in patients with AF and apply the taxonomy to real-world data. Nine expert clinicians (seven clinical pharmacists, two cardiologists) with at least 3years of clinical and research experience in AF participated in a Delphi process. The experts rated and commented on a proposed taxonomy on the potential benefits of OAC switching. After each Delphi round, ratings were analyzed with the RAND Corporation/University of California, Los Angeles (RAND/UCLA) appropriateness method. Median ratings, disagreement index, and comments were used to modify the taxonomy. The resulting taxonomy from the Delphi process was applied to a cohort of patients with AF who switched OACs in a population-based administrative health dataset from 1996 to 2019 in British Columbia, Canada. The taxonomy was finalized in two Delphi rounds, reaching consensus on five switch benefit categories: safety, effectiveness, convenience, economic considerations, and drug interactions. Safety benefit (a switch that could lower the risk of adverse drug events) had three subcategories: major bleeding, intracranial hemorrhage (ICH), and gastrointestinal (GI) bleeding. Effectiveness benefit had four subcategories: stroke and systemic embolism (SSE), ischemic stroke, myocardial infarction (MI), and all-cause mortality. Real-world OAC switches revealed that more OAC switches had convenience (72.6%) and drug interaction (63.0%) benefits compared to effectiveness (SSE 22.0%, ischemic stroke 11.1%, MI 3.1%, all-cause mortality 10.1%), safety (major bleeding 24.3%, GI bleeding 10.6%, ICH 48.5%), and economic benefits (12.1%). The Delphi-based taxonomy identified five criteria for the beneficial effects of OAC switching, aiding in characterizing real-world OAC switching.

The Role of Direct Oral Anticoagulants in the Treatment of Cancer-Associated Venous Thromboembolism: Review by Middle East and North African Experts.

Venous thromboembolism is a leading cause of morbidity and mortality in patients with active cancer who require anticoagulation treatment. Choice of anticoagulant is based on careful balancing of the risks and benefits of available classes of treatment: vitamin K antagonists, low-molecular-weight heparin (LMWH), and direct oral anticoagulants (DOACs). Results from randomized controlled trials have shown the consistent efficacy of DOACs versus LMWH in the treatment of cancer-associated venous thromboembolism (VTE). However, increased major gastrointestinal bleeding was observed for edoxaban and rivaroxaban, but not apixaban, compared with LMWH dalteparin. Most guidelines recommend DOACs for the treatment of cancer-associated VTE in patients without gastrointestinal or genitourinary cancer, and with considerations for renal impairment and drug-drug interactions. These updates represent a major paradigm shift for clinicians in the Middle East and North Africa. The decision to prescribe a DOAC for a patient with cancer is not always straightforward, particularly in challenging subgroups of patients with an increased risk of bleeding. In patients with gastrointestinal malignancies who are at high risk of major gastrointestinal bleeds, apixaban may be the preferred DOAC; however, caution should be exercised if patients have upper or unresected lower gastrointestinal tumors. In patients with gastrointestinal malignancies and upper or unresected lower gastrointestinal tumors, LMWH may be preferred. Vitamin K antagonists should be used only when DOACs and LMWH are unavailable or unsuitable. In this review, we discuss the overall evidence for DOACs in the treatment of cancer-associated VTE and provide treatment suggestions for challenging subgroups of patients with cancer associated VTE.

Effectiveness and Safety of Different Oral Anticoagulants with P-glycoprotein/ CYP3A4 Inhibitors: A Network Meta-analysis.

Metabolism of oral anticoagulants (OAC) is affected by P-glycoprotein (P-gp)/ CYP3A4 enzyme. However, the P-gp/CYP3A4 inhibitors are unavoidably used with OACs. Medline, Cochrane, and Embase were systematically searched for randomized controlled trials and cohort studies from inception till 23rd November, 2022 to assess the safety and effectiveness of OACs when concomitantly used with P-gp/CYP3A4 inhibitors. The primary outcomes were major bleeding and gastrointestinal (GI) bleeding. Secondary outcomes were stroke/systemic embolism (SE), all-cause mortality, any bleeding as well as intracranial hemorrhage (ICH). We estimated summary odds ratios (OR) with 95% credible intervals (CI) using pairwise and network meta-analysis with random effects. A total of 11 studies involving 37,973 patients were included. When concomitantly used with P-pg/ CYP3A4 inhibitors, network meta-analysis indicated that dabigatran, apixaban, and edoxaban were associated with significantly lower risk of major bleeding compared to rivaroxaban, with ORs of 0.56, 0.51 and 0.48, respectively. Rivaroxaban and dabigatran were associated with a significantly increased risk of GI bleeding than warfarin, apixaban and edoxaban. Dabigatran and apixaban were linked with significantly lower risk of any bleeding compared with warfarin (ORs were 0.75 and 0.68, respectively) or rivaroxaban (ORs were 0.67 and 0.60, respectively). Apixaban (OR 0.32) and edoxaban (OR 0.35) were associated with a lower risk of ICH compared with warfarin. There was no difference between any OACs in terms of stroke/SE or all-cause mortality. When concomitantly used with P-gp/CYP3A4 inhibitors, apixaban and edoxaban were associated with a lower risk of bleeding, though no significant difference in effectiveness was observed among all OACs.

Aetiology and predictors of major bleeding events in patients with heart failure with reduced ejection fraction undergoing percutaneous coronary intervention

ObjectivesWe sought to determine the relationship between the degree of left ventricular ejection fraction (LVEF) impairment and the frequency and type of bleeding events after percutaneous coronary intervention (PCI).DesignThis was...

Clinical Characteristics and Incidence of Hemorrhagic Complications in Patients Taking Factor Xa Inhibitors in Spain: A Long-Term Observational Study.

Objective. To analyze the clinical characteristics of patients taking Factor Xa inhibitors (FXai), either direct FXai or enoxaparin (only in active cancer patients), and to estimate the incidence of and risk factors for major bleeding during FXai use. Methods. A retrospective cohort study, which included secondary data from computerized health records of primary care centers and hospitals in seven Spanish Autonomous Communities. Results. 9374 patients were analyzed, with 8972 taking direct FXai and 402 enoxaparin. At baseline, the mean age (SD) was 71.8 (9.4) years, 56.0% were women, 76.3% had hypertension, 33.6% had type 2 diabetes, and 25.5% had heart failure. The most common indication for FXai use was atrial fibrillation (72.3%), followed by venous thromboembolism (22.2%) and non-mechanical cardiac-valve replacement (5.6%). At the end of the follow-up period, the incidence rates of major bleeding overall, gastrointestinal, and intracranial were 10.2, 9.0, and 0.8 per 100 person-years, respectively. The total incidence of fatal major bleeding was 0.5 per 100 person-years. Incidence rates of all bleedings progressively decreased over time, with 62.5% of the first events occurring in the initial three months and reaching 76.8% within six months following initiation of treatment. Only 4.8% of the 1st major bleedings led to death, 2.3% in the case of major gastrointestinal bleeding, and 30.8% after an intracranial bleeding. 65.9% of patients discontinued anticoagulation after experiencing major bleeding. Conclusions. In Spain, patients taking FXai were old and had many comorbidities. Despite incidence rates of major bleeding were high, incidence rates of intracranial and fatal bleedings were low, but more efforts are required due to their relevant clinical impact.

A284 EVALUATING THE INCIDENCE OF MAJOR GASTROINTESTINAL BLEEDING IN PATIENTS WITH CIRRHOSIS ON ANTICOAGULATION THERAPY: A TERTIARY SINGLE CENTRE EXPERIENCE

Abstract Background Patients with chronic liver disease, especially those with cirrhosis, face an increased risk of bleeding and thrombosis due to hemostasis dysregulation. In such cases, prescribing anticoagulation therapy requires a cautious approach, given the inherent risk-reduction in thrombosis alongside a suspected elevated bleeding risk. Aims Perform a retrospective study to evaluate anticoagulation safety and gastrointestinal bleeding incidence in cirrhotic patients. Methods A retrospective study was conducted at the University Hospital of London Health Sciences Centre, involving patients who attended outpatient hepatology clinics between 2010 and 2022. To be eligible, patients had to be 18 years or older and have confirmed cirrhosis through imaging, radiology, or pathology. They were monitored for up to 5 years for the primary outcome, which was major gastrointestinal bleeding requiring hospitalization. Exclusions included patients with underlying hematologic or thrombotic conditions contributing to abnormal hemostasis beyond cirrhosis and those who underwent liver transplantation. Descriptive statistics were provided, such as means and standard deviations for continuous variables, and proportions/percentages for categorical ones. Group comparisons utilized the Student's t-test for continuous variables and chi-squared tests for categorical variables. Univariate and multivariate logistic regression were employed to calculate odds ratios and their associated 95% confidence intervals for the primary outcome Results We retrospectively enrolled 300 patients, with 34.0% having cirrhosis and anticoagulation history. The average age was 63.1 years [95% CI 61.7 – 64.6], and 43.7% were female. Atrial fibrillation was the primary reason for anticoagulation (53.9%). Cirrhotic patients on anticoagulation had a 13.1% bleeding rate, while those without had 18.6% (p-value = 0.207, not significant). Univariate analysis suggested a possible link between anticoagulation and bleeding risk (OR 1.51 [95% CI 0.79 – 2.89]). No covariates predicted bleeding in univariate logistic regression. In multivariate analysis adjusting for age and sex, the odds ratio remained at 1.50 [95% CI 0.78 – 2.88]. The study hints at a higher bleeding risk in cirrhotic patients on anticoagulation, but more statistical power is needed, either through a larger sample or a multicenter approach. Conclusions To further investigate the association between anticoagulation and bleeding risk in cirrhotic patients, a larger multicentre study with increased enrollment is required. Nonetheless, interim findings do suggest the potential existence of an associated bleeding risk in cirrhotic patients undergoing anticoagulation therapy, albeit with a small observed effect size and uncertain clinical significance. Funding Agencies None

State-of-the-Art of Transcatheter Left Atrial Appendage Occlusion.

Left atrial appendage occlusion (LAAO) is an increasingly used alternative to oral anticoagulation in patients with atrial fibrillation, especially in patients with absolute/relative contraindications to these therapies. This review will cover three main aspects of the procedure. In the fist part of the manuscript, we focus on patient selection. We describe three main categories of patients with primary indication to LAAO, namely patients with previous or at a high risk of intracerebral bleeding, patients with a history of major gastrointestinal bleeding and patients with end-stage renal disease and absolute contraindication to novel oral anticoagulants. Some other potential indications are also described. In the second part of the manuscript, we review available devices, trying to highlight different aspects and potential specific advantages. The last section overviews different ways for pre-, intra- and postprocedural imaging, in order to improve procedural safety and efficacy and ameliorate patient outcome. The characteristics of available contemporary devices and the role of imaging in procedural planning, intraprocedural guidance and follow-up are described.

Dispensing pharmacy chains and direct anticoagulants: Potential associations with patient outcomes.

Pharmacy chains can differ with respect to the characteristics of their patient populations as well as their nonprescription products, services, and practices, and thus may serve as a surrogate for potential unmeasured confounding in observational studies of prescription drugs. This study evaluates whether a single-source drug can have different patient outcomes based on the dispensing pharmacy chain. Separate analyses for two anticoagulant drugs, rivaroxaban and apixaban, were conducted using Medicare Fee-for-Service claims evaluating the association between dispensing pharmacy chain and outcomes of acute myocardial infarction, ischemic stroke, intracranial hemorrhage, gastrointestinal (GI) bleeding, all-cause mortality, and major GI bleeding. Inverse probability of treatment weighting (IPTW) was used to balance baseline covariates across pharmacy chain cohorts, and outcome association was assessed with a Cox Proportional Hazards model. We observed no differences in outcomes across pharmacy chains for apixaban recipients. Rivaroxaban recipients from pharmacy chain C, however, had lower rates of GI bleeding (adjusted HR 0.83; 95% CI 0.69-1.00) and ischemic stroke (adjusted HR 0.57; 95% CI 0.38-0.87) as compared to chain A in primary analyses with a 3-day grace period. The results moved closer to the null when 14- and 30-day grace periods were implemented. These results suggest that dispensing pharmacy chains may have the potential to act as a confounder of associations between drug exposure and outcome in some observational studies. Additional studies of potential confounding by pharmacy chain are needed. Further evaluation of potential pharmacy chain effects on safe use would be of value.