Real-world Data on Treatment Patterns and Bleeding in Cancer-associated Thrombosis: Data from the TROLL Registry.

Background International guidelines are increasingly recommending direct oral anticoagulants (DOACs) as the first-line treatment for cancer-associated thrombosis (CAT). However, data regarding treatment patterns and adherence to guidelines in patients with CAT are scarce. Objectives This study aimed to explore anticoagulant treatment patterns in patients with CAT and to calculate the incidence rates of bleeding events. Methods Patients ≥18 years with active cancer and a first-time venous thromboembolism between 2005 and 2020 were identified through the Venous T hrombosis R egistry in Østf OL d Hospita L . Outcome measures were patterns of anticoagulant treatment during the study period and bleeding events. We calculated overall incidence rates per 100 person-years and 6- and 12-month cumulative incidence of major and clinically relevant nonmajor bleeding (CRNMB) during anticoagulant treatment. Results Median age of 842 CAT patients at the time of thrombosis was 69 years (interquartile range 61-77), and 443 (52.6%) were men. In total, 526 patients (62.5%) had pulmonary embolism and 255 (30.3%) had deep vein thrombosis. Low molecular weight heparin (LMWH) was prescribed to 713 (85.8%) patients, whereas 64 (7.7%) received DOACs and 54 (6.5%) received vitamin K antagonists as the initial anticoagulant treatment. Prescription of DOACs as initial treatment increased from 3.0% in 2013/2014 to 18.0% in 2019/2020. The incidence rate of major bleeding was 6.9 (95% confidence interval [CI] 5.2-9.2) and 10.1 (95% CI 8.0-12.9) in CRNMB. Conclusion Most patients were treated with LMWH. However, a gradual shift in treatment toward DOACs was observed. Overall, bleeding complications were rare and comparable to those reported in randomized trials.

Developing a machine learning model for bleeding prediction in patients with cancer-associated thrombosis receiving anticoagulation therapy.

BACKGROUND: Only 1 conventional score is available for assessing bleeding risk in patients with cancer-associated thrombosis (CAT): the CAT-BLEED score. OBJECTIVES: Our aim was to develop a machine learning-based risk assessment model for predicting bleeding in CAT and to evaluate its predictive performance in comparison to that of the CAT-BLEED score. METHODS: We collected 488 attributes (clinical data, biochemistry, and International Classification of Diseases, 10th Revision, diagnosis) in 1080 unique patients with CAT. We compared CAT-BLEED score, Ridge and Lasso logistic regression, random forest, and Extreme Gradient Boosting (XGBoost) algorithms for predicting major bleeding or clinically relevant nonmajor bleeding occurring 1 to 90 days, 1 to 365 days, and 90 to 455 days after venous thromboembolism (VTE). RESULTS: The predictive performances of Lasso logistic regression, random forest, and XGBoost were higher than that of the CAT-BLEED score in the prediction of bleeding occurring 1 to 90 days and 1 to 365 days after VTE. For predicting major bleeding or clinically relevant nonmajor bleeding 1 to 90 days after VTE, the CAT-BLEED score achieved a mean area under the receiver operating characteristic curve (AUROC) of 0.48 ± 0.13, while Lasso logistic regression and XGBoost both achieved AUROCs of 0.64 ± 0.12. For predicting bleeding 1 to 365 days after VTE, the CAT-BLEED score achieved a mean AUROC of 0.47 ± 0.08, while Lasso logistic regression and XGBoost achieved AUROCs of 0.64 ± 0.08 and 0.59 ± 0.08, respectively. CONCLUSION: This is the first machine learning-based risk model for bleeding prediction in patients with CAT receiving anticoagulation therapy. Its predictive performance was higher than that of the conventional CAT-BLEED score. With further development, this novel algorithm might enable clinicians to perform personalized anticoagulation strategies with improved clinical outcomes.

Incidence of venous thromboembolism, recurrence, and bleeding after isolated superficial vein thrombosis: findings from the Venous Thrombosis Registry in Østfold Hospital.

BACKGROUND: There are limited data on the long-term risk of venous thromboembolism (VTE) after high-risk isolated superficial vein thrombosis (iSVT) treated with anticoagulants. OBJECTIVES: To determine the short- and long-term risk of VTE and iSVT recurrence after cessation of anticoagulant treatment and to calculate 45-day cumulative bleeding incidence in patients with iSVT. METHODS: Between January 2014 and December 2021, 229 patients with high-risk iSVT (ie, thrombus length ≥5cm), without active cancer, with no history of VTE or iSVT, and who had received anticoagulant treatment for the iSVT were identified through the Venous Thrombosis Registry in Østfold Hospital (TROLL registry), Norway. Cumulative incidences of VTE and iSVT recurrence, as well as cumulative incidences of major and clinically relevant nonmajor bleeding events, were assessed. RESULTS: Median age was 60 years (IQR, 48-71), and 125 (55%) were women. Most patients were treated with direct oral anticoagulants (74%), and of these, 79% received a dose of rivaroxaban 10 mg daily. Low-molecular-weight heparin was given to 26% of the patients. The 1- and 5-year cumulative incidences of VTE after iSVT were 4.6% (95% CI, 2.5-8.3) and 15.9% (95% CI, 10.8-22.9), respectively. Further, the 1- and 5-year cumulative incidences of iSVT recurrence were 6.5% (95% CI, 3.9-10.7) and 15.9% (95% CI, 10.8-23.1), respectively. The overall 45-day cumulative incidence of major and clinically relevant nonmajor bleeding events was 0.4% (95% CI, 0.06-3.06) and 1.8% (95% CI, 0.7-4.6), respectively. No major bleeding events were observed in patients treated with direct oral anticoagulants. CONCLUSION: Despite anticoagulant treatment, the risk of VTE after high-risk iSVT was substantial, while bleeding complications were low.

Incidence of bleeding and recurrence in isolated distal deep vein thrombosis: findings from the Venous Thrombosis Registry in Østfold Hospital.

BACKGROUND: Isolated distal deep vein thrombosis (IDDVT) is a common presentation of deep vein thrombosis. There are limited data on the long-term risk of recurrence after IDDVT. OBJECTIVES: We aimed to determine the short- and long-term incidence of venous thrombosis (VTE) recurrence after cessation of anticoagulation and the 3-month incidence of bleeding during anticoagulant treatment in patients with IDDVT. METHODS: Between January 2005 and May 2020, 475 patients with IDDVT and without active cancer were identified from the Venous Thrombosis Registry in Østfold Hospital, which is an ongoing registry of consecutive patients with VTE at Østfold Hospital, Norway. Major and clinically relevant, nonmajor bleeding as well as recurrent VTE were registered, and the cumulative incidences of these events were assessed. RESULTS: The median age of the patients was 59 years (IQR, 48-72 years), 243 (51%) patients were women, and 175 events (36.8%) were classified as unprovoked. The 1-, 5-, and 10-year cumulative incidences of recurrent VTE were 5.6% (95% CI, 3.7-8.4), 14.7% (95% CI, 11.1-19.4), and 27.2% (95% CI, 21.1-34.5), respectively. The recurrence rates were higher for unprovoked IDDVT than for provoked IDDVT. Among the recurrent events, 18 (29%) were pulmonary embolisms and 21 (33%) were proximal deep vein thromboses. The 3-month cumulative incidence of major bleeding was 1.5% (95% CI, 0.7-3.1) overall and 0.8% (95% CI, 0.2-3.1) when restricted to patients treated with direct oral anticoagulants. CONCLUSION: Despite initial treatment, the long-term risk of VTE recurrence after first-time IDDVT is high. The bleeding rates during anticoagulation, particularly with direct oral anticoagulants, were acceptably low.

SARS-CoV-2 vaccines are not associated with hypercoagulability in apparently healthy people.

Background: SARS-CoV-2 adenoviral vector DNA vaccines have been linked to the rare but serious thrombotic postvaccine complication vaccine-induced immune thrombotic thrombocytopenia. This has raised concerns regarding the possibility of increased thrombotic risk after any SARS-CoV-2 vaccines. Objectives: To investigate whether SARS-CoV-2 vaccines cause coagulation activation leading to a hypercoagulable state. Methods: This observational study included 567 health care personnel; 521 were recruited after the first dose of adenoviral vector ChAdOx1-S (Vaxzevria, AstraZeneca) vaccine and 46 were recruited prospectively before vaccination with a messenger RNA (mRNA) vaccine, either Spikevax (Moderna, n = 38) or Comirnaty (Pfizer-BioNTech, n = 8). In the mRNA group, samples were acquired before and 1 to 2 weeks after vaccination. In addition to the prevaccination samples, 56 unvaccinated blood donors were recruited as controls (total n = 102). Thrombin generation, D-dimer levels, and free tissue factor pathway inhibitor (TFPI) levels were analyzed. Results: No participant experienced thrombosis, vaccine-induced immune thrombotic thrombocytopenia, or thrombocytopenia (platelet count <100 × 109/L) 1 week to 1 month postvaccination. There was no increase in thrombin generation, D-dimer level, or TFPI level in the ChAdOx1-S vaccine group compared with controls or after the mRNA vaccines compared with baseline values. Eleven of 513 (2.1%) participants vaccinated with ChAdOx1-S had anti-PF4/polyanion antibodies without a concomitant increase in thrombin generation. Conclusion: In this study, SARS-CoV-2 vaccines were not associated with thrombosis, thrombocytopenia, increased thrombin generation, D-dimer levels, or TFPI levels compared with baseline or unvaccinated controls. These findings argue against the subclinical activation of coagulation post-COVID-19 vaccination.

The venous thrombosis registry in Østfold Hospital (TROLL registry) - design and cohort description.

Purpose: The incidence of venous thromboembolism (VTE) is expected to increase over the next decades, further increasing its substantial impact on patients and health care resources. Registries have the benefit of reporting real-world data without excluding clinically important subgroups. Our aim was to describe a Norwegian VTE registry and to provide descriptive data on the population and management. Registry Population: The Venous Thrombosis Registry in Østfold Hospital (TROLL) is an ongoing registry of consecutive patients diagnosed with, treated, and/or followed up for VTE at Østfold Hospital, Norway, since 2005. Baseline and follow-up data, including demographics, clinical features, risk factors, diagnostic procedures, classification of VTE, and treatment were collected during hospitalization, and at scheduled outpatient visits. Findings to Date: From January 2005 to June 2021, 5037 patients were eligible for research in TROLL. Median age was 67 years (interquartile range, 55-77), and 2622 (52.1%) were male. Of these, 2736 (54.3%) had pulmonary embolism (PE), 2034 (40.4%) had deep vein thrombosis (DVT), and 265 (5.3%) had upper-extremity DVT or splanchnic or cerebral sinus vein thrombosis. In total, 2330 (46.3%) were classified as unprovoked VTE, and 1131 (22.5%) had cancer. Direct oral anticoagulants were the most frequent therapeutic agents (39.3%) followed by low-molecular-weight heparins (30.4%) and vitamin K antagonists (30.3%). Outpatient treatment for PE increased from 4% in 2005 to 23% in 2019. Future Plans: TROLL is a population-based ongoing registry that represents a valuable source of real-world data that will be used for future research on the management and outcomes of VTE.