2023 ACR/EULAR antiphospholipid syndrome classification criteria.

OBJECTIVE: To develop new antiphospholipid syndrome (APS) classification criteria with high specificity for use in observational studies and trials, jointly supported by the American College of Rheumatology (ACR) and EULAR. METHODS: This international multidisciplinary initiative included four phases: (1) Phase I, criteria generation by surveys and literature review; (2) Phase II, criteria reduction by modified Delphi and nominal group technique exercises; (3) Phase III, criteria definition, further reduction with the guidance of real-world patient scenarios, and weighting via consensus-based multicriteria decision analysis, and threshold identification; and (4) Phase IV, validation using independent adjudicators' consensus as the gold standard. RESULTS: The 2023 ACR/EULAR APS classification criteria include an entry criterion of at least one positive antiphospholipid antibody (aPL) test within 3 years of identification of an aPL-associated clinical criterion, followed by additive weighted criteria (score range 1-7 points each) clustered into six clinical domains (macrovascular venous thromboembolism, macrovascular arterial thrombosis, microvascular, obstetric, cardiac valve, and hematologic) and two laboratory domains (lupus anticoagulant functional coagulation assays, and solid-phase enzyme-linked immunosorbent assays for IgG/IgM anticardiolipin and/or IgG/IgM anti-ß2-glycoprotein I antibodies). Patients accumulating at least three points each from the clinical and laboratory domains are classified as having APS. In the validation cohort, the new APS criteria vs the 2006 revised Sapporo classification criteria had a specificity of 99% vs 86%, and a sensitivity of 84% vs 99%. CONCLUSION: These new ACR/EULAR APS classification criteria were developed using rigorous methodology with multidisciplinary international input. Hierarchically clustered, weighted, and risk-stratified criteria reflect the current thinking about APS, providing high specificity and a strong foundation for future APS research.

Risk of venous thromboembolism or hemorrhage among individuals with chronic kidney disease on prophylactic anticoagulant after hip or knee arthroplasty.

Chronic kidney disease (CKD) confers a high risk of thrombosis and bleeding. However, little evidence exists regarding the optimal choice of postoperative thromboprophylaxis in these patients. We conducted a population-based, retrospective cohort study among adults ≥66 years old with CKD undergoing hip or knee arthroplasty who had filled an outpatient prophylactic anticoagulant prescription between 2010 and 2020 in Ontario, Canada. The primary outcomes of venous thrombosis (VTE) and hemorrhage were identified by validated algorithms using relevant diagnoses and billing codes. Overlap-weighted cause-specific Cox proportional hazard models were used to examine the association of direct oral anticoagulants (DOAC) on the 90-day risk of VTE and hemorrhage compared with low-molecular-weight heparin (LMWH). A total of 27 645 patients were prescribed DOAC (N = 22 943) or LMWH (N = 4702) after arthroplasty. Rivaroxaban was the predominant DOAC (94.5%), while LMWH mainly included enoxaparin (67%) and dalteparin (31.5%). DOAC users had higher eGFRs, fewer co-morbidities, and surgery in more recent years compared to LMWH users. After weighing, DOAC (compared with LMWH) was associated with a lower risk of VTE (DOAC: 1.5% vs. LMWH: 2.1%, weighted hazard ratio [HR] 0.75, 95% confidence interval [CI] 0.59-0.94) and a higher risk of hemorrhage (DOAC: 1.3% vs. LMWH: 1.0%, weighted HR 1.44, 95% CI 1.04-1.99). Additional analyses including a more stringent VTE defining algorithm, different eGFR cut-offs, and limiting to rivaroxaban and enoxaparin showed consistent findings. Among elderly adults with CKD, DOAC was associated with a lower VTE risk and a higher hemorrhage risk compared to LMWH following hip or knee arthroplasty.

Accuracy of the Ottawa score in risk stratification of recurrent venous thromboembolism in patients with cancer-associated venous thromboembolism: a systematic review and meta-analysis.

In patients with cancer-associated venous thromboembolism, knowledge of the estimated rate of recurrent events is important for clinical decision-making regarding anticoagulant therapy. The Ottawa score is a clinical prediction rule designed for this purpose, stratifying patients according to their risk of recurrent venous thromboembolism during the first six months of anticoagulation. We conducted a systematic review and meta-analysis of studies validating either the Ottawa score in its original or modified versions. Two investigators independently reviewed the relevant articles published from 1st June 2012 to 15th December 2018 and indexed in MEDLINE and EMBASE. Nine eligible studies were identified; these included a total of 14,963 patients. The original score classified 49.3% of the patients as high-risk, with a sensitivity of 0.7 [95% confidence interval (CI): 0.6-0.8], a 6-month pooled rate of recurrent venous thromboembolism of 18.6% (95%CI: 13.9-23.9). In the low-risk group, the recurrence rate was 7.4% (95%CI: 3.4-12.5). The modified score classified 19.8% of the patients as low-risk, with a sensitivity of 0.9 (95%CI: 0.4-1.0) and a 6-month pooled rate of recurrent venous thromboembolism of 2.2% (95%CI: 1.6-2.9). In the high-risk group, recurrence rate was 10.2% (95%CI: 6.4-14.6). Limitations of our analysis included type and dosing of anticoagulant therapy. We conclude that new therapeutic strategies are needed in patients at high risk for recurrent cancer-associated venous thromboembolism. Low-risk patients, as per the modified score, could be good candidates for oral anticoagulation. (This systematic review was registered with the International Prospective Registry of Systematic Reviews as: PROSPERO CRD42018099506).

Incidence and impact of atrial arrhythmias on thrombotic events in MPNs.

Atrial arrhythmias (AA) induce a high rate of thromboses and require vitamin K antagonists (VKA) or direct anticoagulants (DOAC) prescriptions. Essential thrombocythemia (ET) and polycythemia vera (PV) are also pro-thrombotic diseases. The prevention of thromboses is based on the association of cytoreductive drug and low-dose aspirin (LDA). We studied the incidence and complications of AA among patients with ET or PV. We identified 96/713 patients (13.5%) carrying AA. These patients were older (median 72.1 vs. 61.3 years old, p < 0.0001). In a case-control analysis, we observed that patients with AA had a higher frequency of cardiovascular risk factors (77/96, 80% vs. 61/96, 61%; p = 0.01). A higher incidence of thromboses before and after myeloproliferative neoplasm (MPN) diagnosis was seen in this group: 26/96, 27.1% vs. 14/96, 14.6% (p = 0.03) and 34/96, 35% vs. 18/96, 18.8% (p = 0.009). Most of the events were arterial (82 vs. 61%, p = 0.09). This translates into a shorter thrombosis-free survival (11.0 vs. 21.6 years, p = 0.01). Continuation of LDA in this situation exposed patients to more thrombotic events (p = 0.04) but VKA did not seem to be good anticoagulant drugs either. The association of AA and MPN is more frequent than expected. AA clearly increased the thrombotic risk of these patients. Anticoagulant drugs should be carefully managed between cardiologists and hematologists. Association of LDA and VKA or the role of DOAC in such population should be rapidly discussed to reduce the thrombotic rate.

Risk of recurrent venous thromboembolism in COPD patients: results from a prospective cohort study.

We aimed to assess the risk of recurrent venous thromboembolism (VTE) in patients with chronic obstructive pulmonary disease (COPD) following cessation of anticoagulation therapy.In a prospective cohort of 1468 patients with a documented episode of VTE, followed for up to 5 years after cessation of anticoagulation therapy, the diagnosis of COPD was confirmed in 136. The main outcome was recurrent VTE. The secondary outcome was overall mortality. Univariate and multivariate analyses were performed to identify the risk factors of recurrence.Of the 1468 patients included, recurrent VTE was observed in 306 (34 with COPD and 272 without) during a median follow-up period of 36.5 months. The incidence rate of recurrent VTE was 9.1% (95% CI 6.5-12.8) for COPD patients and 7.0% (95% CI 6.2-7.9) for non-COPD patients. COPD was not associated with an increased risk of VTE recurrence on univariate or multivariate analyses (hazard ratio: 1.0 (95% CI 0.7-1.4)). The risk of death, adjusted for demographic and clinical characteristics, showed no increase in COPD patients, as compared to non-COPD patients.In patients with COPD who had an acute episode of VTE, the risk of recurrent VTE was not any higher than that in non-COPD patients.

JAK2V617F and calreticulin mutations in recurrent venous thromboembolism: results from the EDITH prospective cohort.

Cancer incidence in patients with recurrent unprovoked venous thromboembolism (VTE) is much higher than after a first event, but the incidence of myeloproliferative neoplasms (MPN) in this situation is still unknown. We tested for JAK2V617F and calreticulin mutants, 372 DNA samples of patients treated for (VTR). Among these patients, 10 (2.7%) were carrying JAK2V617F mutation and none of them any of the calreticulin (CALR) mutations. Among the 19 patients who had VTE recurrence under vitamin K antagonists, 4 patients (21.0%) were positive for JAK2V617F. Despite the identification of JAK2V617F mutation, only three patients were diagnosed for MPN despite a median follow-up of 4 years. We showed that the screening for JAK2V617F not CALR mutations should be helpful in this indication especially if recurrence happened under VKA therapy.

Progression of early repolarization patterns at a four year follow-up in a female flight crew population: Implications for aviation medicine.

BACKGROUND: To assess the prevalence, the appearance, and the distribution, as well as the fluctuation over time of early repolarization patterns after four years in a female population derived from the French aviation sector. METHODS: This was a retrospective longitudinal study from 1998 to 2010 of a population of female employees who received a full clinical examination and an electrocardiogram (ECG) upon their recruitment and after a period of four years. RESULTS: A total of 306 women were included (average of 25.87 ± 3.3 years of age). The prevalence of early repolarization was 9.2%. The most common appearance was J-point slurring for 64.3% (i.e. 20/28 subjects) that occurred in the inferior leads for 28.6% (i.e. 8/28 subjects). After four years, the prevalence was 7.5%, with a regression of this aspect in five of the subjects. There were no changes in the ECG in terms of the distribution and the appearance among the 23 subjects for whom the aspect persisted. Over the course of this four year period all of the subjects remained asymptomatic. CONCLUSIONS: Early repolarization in this largely physically inactive female population was common, and it fluctuated over time. At present, no particular restrictions can be placed on asymptomatic flight crew who exhibit this feature in the absence of a prior medical history for heart disease.

Limited screening with versus without (18)F-fluorodeoxyglucose PET/CT for occult malignancy in unprovoked venous thromboembolism: an open-label randomised controlled trial.

BACKGROUND: Clear guidelines for the investigation of occult malignancy after unprovoked venous thromboembolism are not yet available. (18)F-fluorodeoxyglucose ((18)F-FDG) PET/CT could serve as a comprehensive screening strategy for occult malignancy in this context. We aimed to compare a screening strategy based on (18)F-FDG PET/CT with a limited screening strategy for detection of malignant disease in patients with unprovoked venous thromboembolism. METHODS: In an open-label, multicentre, randomised study we enrolled patients from four French university hospitals. Patients aged 18 years or older, diagnosed with unprovoked venous thromboembolism (not provoked by a major inherited or acquired risk factor) were invited to participate. Patients were randomly assigned in a 1:1 ratio to a limited screening strategy (physical examination, usual laboratory tests, and basic radiographs) or a screening strategy consisting of the limited strategy plus an (18)F-FDG PET/CT scan. Randomisation was done with a dedicated central web-based randomisation system, in block sizes of six, stratified by centre, and concealed from the investigators. Patients and investigators were not masked to study group assignment. Patients were followed up for 2 years. The primary outcome was the proportion of patients with a cancer diagnosis in each group after the initial screening assessment. Analyses were conducted in modified intention-to-test and per-protocol populations. This trial is completed and registered with ClinicalTrials.gov, number NCT00964275. FINDINGS: Between March 3, 2009, and Aug 18, 2012, we enrolled and randomly assigned 399 patients; five withdrew consent, leaving 197 in each group for the modified intention-to-test analysis. After initial screening assessment, cancer was diagnosed in 11 (5·6%) patients in the (18)F-FDG PET/CT group and four (2·0%) patients in the limited screening group (absolute risk difference 3·6%, 95% CI -0·4 to 7·9; p=0·07). At the initial screening assessment, seven (64%) of the 11 cancers diagnosed in the (18)F-FDG PET/CT group were early-stage compared with two of four cancers diagnosed in the limited screening group (p=1·00). One (0·5%) occult malignancy was detected in 186 patients who had negative initial screening in the (18)F-FDG PET/CT group, compared with nine (4·7%) in 193 patients in the limited screening group (absolute risk difference 4·1%, 95% CI 0·8 to 8·4, p=0·01). Overall, five (42%) of the 12 cancers diagnosed in the (18)F-FDG PET/CT group were advanced stage, compared with seven (54%) of the 13 cancers diagnosed in the limited screening group (p=0·70). 16 patients died during follow-up, eight (4·1%) in each group. Two (1·0%) patients in the (18)F-FDG PET/CT group and five (2·5%) in the limited screening group had cancer-related deaths. INTERPRETATION: A strategy including limited screening and a (18)F-FDG PET/CT was not associated with a significantly higher rate of cancer diagnosis after unprovoked venous thromboembolism. The risk of subsequent cancer diagnosis was, however, lower in patients who had negative initial screening that included (18)F-FDG PET/CT than in patients who had negative initial limited screening. Whether or not (18)F-FDG PET/CT might be useful in a more selected population of patients with a high risk of cancer remains to be determined. FUNDING: Programme Hospitalier de Recherche Clinique (French Department of Health).

Prevalence of antiphospholipid antibodies in psychiatric patients users and non-users of antipsychotics.

Past reports have suggested that antiphospholipid (aPL) antibodies may emerge as a response to antipsychotics treatment, as a high prevalence of aPL antibodies in antipsychotics users has been observed. However, no control group of non-medicated psychiatric patients was included in these reports. In a cross sectional study we determined the prevalence of aPL antibodies in 333 psychiatric inpatients. We compared the proportions of positive aPL antibodytests between users and non-users of antipsychotics with adjustments for potential confounders. The proportion of antipsychotics users carrying at least one aPL antibody ranged from 10·8% to 27·0% compared with 6·8% to 27·2% in non-users (P = 0·24, P = 0·24) depending on the method of detection of lupus anticoagulant (LA). The prevalence of LA detected by dilute Russell viper venom time or partial thromboplastin time-LA was not different between antipsychotics users and non-users (8·1% vs. 5·4%, P = 0·53 and 18·4% vs. 18·2%, P = 0·22), as well as the prevalence of IgM and IgG anti-ß2-glycoprotein-I antibodies, IgM and IgG anti-cardiolipin antibodies(3·8% vs. 2·0%, P = 0·75, 0·0% vs. 0·0%, P = not applicable, 1·1 vs. 1·4%, P = 0·91, 2·7% vs. 3·4%, P = 0·71). In conclusion, aPL antibodies were frequently found in patients with psychiatric diseases and no significant increase in the prevalence of aPL antibodies was observed in antipsychotics users.

Safety of ventilation/perfusion single photon emission computed tomography for pulmonary embolism diagnosis.

PURPOSE: The aim of this management outcome study was to assess the safety of ventilation/perfusion single photon emission computed tomography (V/Q SPECT) for the diagnosis of pulmonary embolism (PE) using for interpretation the criteria proposed in the European Association of Nuclear Medicine (EANM) guidelines for V/Q scintigraphy. METHODS: A total of 393 patients with clinically suspected PE referred to the Nuclear Medicine Department of Brest University Hospital from April 2011 to March 2013, with either a high clinical probability or a low or intermediate clinical probability but positive D-dimer, were retrospectively analysed. V/Q SPECT were interpreted by the attending nuclear medicine physician using a diagnostic cut-off of one segmental or two subsegmental mismatches. The final diagnostic conclusion was established by the physician responsible for patient care, based on clinical symptoms, laboratory test, V/Q SPECT and other imaging procedures performed. Patients in whom PE was deemed absent were not treated with anticoagulants and were followed up for 3 months. RESULTS: Of the 393 patients, the prevalence of PE was 28 %. V/Q SPECT was positive for PE in 110 patients (28 %) and negative in 283 patients (72 %). Of the 110 patients with a positive V/Q SPECT, 78 (71 %) had at least one additional imaging test (computed tomography pulmonary angiography or ultrasound) and the diagnosis of PE was eventually excluded in one patient. Of the 283 patients with a negative V/Q SPECT, 74 (26 %) patients had another test. The diagnosis of PE was finally retained in one patient and excluded in 282 patients. The 3-month thromboembolic risk in the patients not treated with anticoagulants was 1/262: 0.38 % (95 % confidence interval 0.07-2.13). CONCLUSION: A diagnostic management including V/Q SPECT interpreted with a diagnostic cut-off of "one segmental or two subsegmental mismatches" appears safe to exclude PE.

Management of catheter-related upper extremity deep vein thrombosis in patients with cancer: a systematic review and meta-analysis.

BACKGROUND: Patients with cancer commonly require a central venous catheter, which is associated with an increased risk of venous thromboembolism (VTE). Despite the frequent occurrence, the optimal anticoagulation management and outcomes for patients with cancer and catheter-related upper extremity deep vein thrombosis (DVT) are unclear. OBJECTIVE: We performed a systematic review and meta-analysis to evaluate the rates of recurrent VTE and bleeding in patients with cancer and catheter-related upper extremity DVT. METHODS: We searched MEDLINE, Embase, Scopus, and CENTRAL from inception to June 2, 2023. The primary efficacy outcome was recurrent VTE, and the primary safety outcome was major bleeding. The incidence rates (with 95% CI) of outcomes were pooled using random effects model. RESULTS: We included 29 studies (N = 2,836), among which 5 were prospective. The duration of follow-up and anticoagulation varied considerably. The main long-term anticoagulant used was low molecular weight heparin, followed by direct oral anticoagulants. The pooled 3-month recurrent VTE rate from 14 studies (N = 1,128) was 0.56% (95% CI, 0.10%-3.01%; I2 = 0%). The pooled 3-month major bleeding rate from 10 studies (N = 834) was 2.34% (95% CI, 1.14%-4.76%; I2 = 0%). We were unable to pool event rates beyond 3 months, given high heterogeneity. All studies had serious risk of bias. CONCLUSIONS: Our study demonstrated a relatively low rate of recurrent VTE and moderate rate of major bleeding events within the first 3 months in patients with cancer and catheter-related upper extremity DVT. However, there was significant heterogeneity in the management and reporting after 3 months.

Risk of developing post thrombotic syndrome after deep vein thrombosis with different anticoagulant regimens: A systematic review and pooled analysis.

BACKGROUND: Post-thrombotic syndrome (PTS) is common in patients with deep vein thrombosis (DVT). It is unclear if different types of anticoagulant therapies (e.g. vitamin K antagonists (VKA), direct oral anticoagulants (DOACs) or low molecular weight heparin (LMWH)) are associated with different risks of PTS. We sought to assess the incidence rates of PTS development following a proximal DVT of the lower extremity managed with different types of anticoagulation regimens. METHODS: A systematic search of MEDLINE, EMBASE and PubMed, from inception to June 2023 was performed. The primary outcome was development of PTS. The secondary outcomes included severe PTS, venous ulcers, and major bleeding. Incidence rates were pooled using the random effects model and expressed as event per 100 patient-years with its associated 95 % confidence intervals (CI) using R software. RESULTS: A total of 21 (4342 patients) articles were included in the analysis. The adjusted pooled incidence of PTS was 15.1 (95 % CI: 8.7 to 26.1), 18.2 (95 % CI: 9.4 to 35.1) and 24.6 (95 % CI: 9.2 to 65.5) per 100 patient-years patients managed with VKA, DOAC and LMWH, respectively. The adjusted pooled incidence of severe PTS was 5.1 (95 % CI: 2.6 to 10.0) and 0.2 (95 % CI: 0.01 to 2.7) per 100 patient-years for VKAs and DOACs, respectively. CONCLUSIONS: The development of PTS is common in patients with proximal lower extremity DVT. The incidence rates of PTS seem to be similar across the different anticoagulation regimens, but severe PTS may be lower among patients receiving a DOAC.

Obesity as a Predictor for Pulmonary Embolism and Performance of the Age-Adjusted D-Dimer Strategy in Obese Patients with Suspected Pulmonary Embolism.

INTRODUCTION: Obesity is a risk factor for venous thromboembolism, but studies evaluating its association with pulmonary embolism (PE) in patients with suspected PE are lacking. OBJECTIVES: To evaluate whether body mass index (BMI) and obesity (i.e., BMI ≥30 kg/m2) are associated with confirmed PE in patients with suspected PE and to assess the efficiency and safety of the age-adjusted D-dimer strategy in obese patients. METHODS: We conducted a secondary analysis of a multinational, prospective study, in which patients with suspected PE were managed according to the age-adjusted D-dimer strategy and followed for 3 months. Outcomes were objectively confirmed PE at initial presentation, and efficiency and failure rate of the diagnostic strategy. Associations between BMI and obesity, and PE were examined using a log-binomial model that was adjusted for clinical probability and hypoxia. RESULTS: We included 1,593 patients (median age: 59 years; 56% women; 22% obese). BMI and obesity were not associated with confirmed PE. The use of the age-adjusted instead of the conventional D-dimer cut-off increased the proportion of obese patients in whom PE was considered ruled out without imaging from 28 to 38%. The 3-month failure rate in obese patients who were left untreated based on a negative age-adjusted D-dimer cut-off test was 0.0% (95% confidence interval: 0.0-2.9%). CONCLUSION: BMI on a continuous linear scale and obesity were not predictors of confirmed PE among patients presenting with a clinical suspicion of PE. The age-adjusted D-dimer strategy appeared safe in ruling out PE in obese patients with suspected PE.

Impact of limited language proficiency on participation in venous thromboembolism research: A retrospective analysis.

BACKGROUND: Limited language proficiency is an established barrier to research participation among racialized populations. While prior studies have highlighted the under-representation of racialized populations in venous thromboembolism (VTE) research, the impact of limited language proficiency as a reason for non-consent among eligible patients is unknown. METHODS: We reviewed all prospective VTE studies conducted at a research-intensive academic thrombosis research program in Canada between 2014 and 2024. Studies with screening logs that systematically and consecutively captured eligibility assessment and reasons for non-consent were included. Primary outcome was non-consent of a screen-eligible patient due to limited language proficiency as the reported reason. We derived pooled estimates of non-consents due to limited language proficiency as a proportion of consented participants, and determined subgroup rates by phase of VTE management, associated medical conditions, and recruitment settings. RESULTS: Screening logs of 28 studies with 22,057 screening events, 8,317 screen-eligible patients and 3,320 consented participants were included. For every 100 consented participants, 3.2 (95% CI 2.0 - 5.3) screen-eligible individuals were unable to be consented due to limited language proficiency. Rates of non-consent were highest in studies involving cancer (5.6 per 100 participants, 95% CI 2.9 - 10.4) and in studies recruiting patients from ambulatory settings outside of the thrombosis clinic (10.8 per 100 participants, 95% CI 4.8 - 22.6). CONCLUSIONS: Language proficiency is a key barrier to VTE research participation. Urgent implementation of targeted interventions aimed at mitigating linguistic barriers is essential to ensure equitable opportunities for VTE research participation for racialized patients disproportionately affected by language proficiency.

Risk assessment tools for bleeding in patients with unprovoked venous thromboembolism: an analysis of the PLATO-VTE study.

BACKGROUND: Guidelines suggest indefinite anticoagulation after unprovoked venous thromboembolism (VTE) unless the bleeding risk is high, yet there is no consistent guidance on assessing bleeding risk. OBJECTIVES: This study aimed to evaluate the performance of 5 bleeding risk tools (RIETE, VTE-BLEED, CHAP, VTE-PREDICT, and ABC-Bleeding). METHODS: PLATO-VTE, a prospective cohort study, included patients aged ≥40 years with a first unprovoked VTE. Risk estimates were calculated at VTE diagnosis and after 3 months of treatment. Primary outcome was clinically relevant bleeding, as per International Society on Thrombosis and Haemostasis criteria, during 24-month follow-up. Discrimination was assessed by the area under the receiver operating characteristic curve (AUROC). Patients were classified as having a "high risk" and "non-high risk" of bleeding according to predefined thresholds; bleeding risk in both groups was compared by hazard ratios (HRs). RESULTS: Of 514 patients, 38 (7.4%) had an on-treatment bleeding. AUROCs were 0.58 (95% CI, 0.48-0.68) for ABC-Bleeding, 0.56 (95% CI, 0.46-0.66) for RIETE, 0.53 (95% CI, 0.43-0.64) for CHAP, 0.50 (95% CI, 0.41-0.59) for VTE-BLEED, and 0.50 (95% CI, 0.40-0.60) for VTE-PREDICT. The proportion of high-risk patients ranged from 1.4% with RIETE to 36.9% with VTE-BLEED. The bleeding incidence in the high-risk groups ranged from 0% with RIETE to 13.0% with ABC-Bleeding, and in the non-high-risk groups, it varied from 7.7% with ABC-Bleeding to 9.6% with RIETE. HRs ranged from 0.93 (95% CI, 0.46-1.9) for VTE-BLEED to 1.67 (95% CI, 0.86-3.2) for ABC-Bleeding. Recalibration at 3-month follow-up did not alter the results. CONCLUSION: In this cohort, discrimination of currently available bleeding risk tools was poor. These data do not support their use in patients with unprovoked VTE.