Peterson, Lisa

Background: Reduced or low-dose direct oral anticoagulants (DOACs) have been studied in randomized control trials for the extended prevention of venous thromboembolism (VTE) after 6 months of treatment at full, therapeutic doses. The real-world effectiveness as well as utilization of this approach in clinical practice compared to continuing at therapeutic doses is unclear. Aims: Examine the effectiveness, safety and utilization of reduced-dose DOACs in cancer patients and overweight patients. Methods: Consecutive patients with VTE were identified using the Mayo Clinic VTE Registry from March 1st, 2013 to December 31st, 2021. Patients were followed prospectively for outcomes of VTE recurrence, death, major bleeding and clinically relevant non major bleeding (CRNMB) either in person or by survey. Patients with recurrent VTE or bleeding during the first 3 months were excluded from further analysis. After completion of anticoagulation treatment for 3 months with either rivaroxaban or apixaban, patients continuing anticoagulation were evaluated in a nested case-control study. Results: A total of 404 patients (283 (70%) on apixaban and 121 (30%) on rivaroxaban) were identified in the low dose DOAC and 3060 in the full dose anticoagulation group. Overall, the mean age was 60.7 years (SD 14.4), mean weight was 89.9 kg (SD 23.8) and 55.1% were males. Within the full cohort, patients with active cancer were less likely to be prescribed low dose DOACs (HR 0.56; 95%CI 0.42-0.73; p<0.001). However, low dose DOAC prescription was more likely in patients with pulmonary embolism alone (HR 1.48; 95%CI 1.21-1.80; p<0.001) or in combination with DVT (HR 1.54; 95%CI 1.25,1.90; p<0.001). Patients transitioned to low dose DOACs had similar age, sex and weight compared to the full dose anticoagulation group, however, fewer patients with weight ≥120 kg had reduced dosing (HR 0.68; 95%CI 0.46,0.99; p=0.046). The mean time to start of a low dose DOAC was 5.1 months overall, 5.4 months in cancer patients, and 3.6-4.9 months in non-cancer patients (Table 1). Non-cancer patients had significantly lower transition numbers in those ≥120kg (HR 0.62; 95%CI 0.40,0.97; p=0.038). In non-cancer patients In comparing weight, ≥120kg to <120kg, in the low dose group, only death was statistically different with higher risk in those ≥120kg (HR 6.44; 95%CI1.27,32.81; p=0.025). Cancer patients transitioned to low dose DOACs around 5 months on average with a median of 3.3 months. Apixaban continued to be the dominant DOAC used (78%) in the low dose group. The cancers with the most patients on low dose DOACs include lymphoma, prostate, melanoma, ovarian, and breast. There was no significant difference in VTE recurrence or death in the cancer group on different DOAC doses. Conclusion: Our results show that anticoagulant prescribers are not always waiting until 6 months to transition to low doses and low doses are being utilized in cancer patients despite lack of cancer-specific studies during the analyzed time period. Although the sample size limits the precision of this analysis, we did not find statistically significant increases in VTE recurrence with low dose DOACs in either cancer patients or with elevated body weight. We did find CRNMB but not MB was observed more frequently in weights above 120kg, possibly from unadjusted confounding in this unadjusted analysis.

AbstractBackgroundClinical picture and outcome of incidental pulmonary embolism (iPE) compared to symptomatic pulmonary embolism (sPE) remain unclear.MethodsDemographics, recurrent venous thromboembolism (VTE), mortality, major bleeding, and clinically relevant nonmajor bleeding (CRNMB) were compared between iPE and sPE patients who were followed prospectively at Mayo Thrombophilia Clinic (March 1, 2013 to August 1, 2020).ResultsOut of 3576 VTE patients, 1417 (39.6%) had PE: 562 (39.7%) iPE and 855 sPE. Patients with cancer were more likely to have iPE (400 iPE vs. 314 sPE) compared to those without cancer (162 iPE vs. 541 sPE). VTE recurrence rate (all per 100 person‐years) was similar in all iPE and sPE patients (3.34 vs. 3.68, p = .50), with cancer (4.16 vs. 4.89, p = .370), and without cancer patients (0.89 vs. 2.80, p = .25). Higher mortality observed in all patients with iPE compared to sPE (46.45 vs. 23.47, p < .001) and with cancer (56.41 vs. 45.77, p = .03) became not significant after adjustment for age, antiplatelet therapy, metastases, and cancer location. Noncancer iPE patients had higher mortality (15.95 vs. 7.18, p = .006) even after adjustment (p = .05). The major bleeding rate was also higher in all patients iPE compared to sPE (7.10 vs. 3.68, p = .03), but not after adjustment (p = .974); higher major bleeding rate in noncancer patients (6.49 vs. 1.25, p = .007) remained significant after adjustment (.02). CRNMB rate was similar to iPE and sPE patients.ConclusioniPE represents a more serious clinical condition compared to sPE as indicated by the higher mortality and major bleeding but these differences reflect underlying comorbidities rather than the seriousness of the embolic event.

Abstract Background: Reduced or low-dose direct oral anticoagulants (DOACs) have been studied in randomized control trials for the extended prevention of venous thromboembolism (VTE) after 6 months of treatment at the therapeutic doses. The real-world effectiveness as well as utilization of this approach in clinical practice compared to continuing at therapeutic doses is unknown. Aims: Evaluate the efficacy of reduced-dose DOACs compared to standard therapeutic anticoagulation in patients with extended anticoagulation. Methods: Consecutive patients with VTE were identified using the Mayo Clinic VTE Registry from March 1st , 2013 to December 31st, 2020. Patients were followed prospectively for outcomes of VTE recurrence, death, major bleeding and clinically relevant non major bleeding (CRNMB) either in person or by survey. Type of anticoagulation and dose changes were recorded, and progressing to a low dose was treated as an endpoint. In the models relating it to the outcome, it was treated as a time-dependent covariate in the cox models. After completing standard anticoagulation treatment for 3 months with any anticoagulant, patients continuing anticoagulation were divided into two groups: standard therapeutic anticoagulation (any drug) vs those who transitioned to rivaroxaban 10 mg daily or apixaban 2.5mg twice daily any time after 3 months. Patients with recurrent VTE, major or CRNMB during the first 3 months were excluded from further analysis. Results: 219 patients (153 on Apixaban and 66 on Rivaroxaban) were identified in the low dose DOAC and 2521 in the standard anticoagulation group. The mean age was 60.7 years, mean weight was 93.2 Kg and 55.9% were males (Table 1). Patients on low dose DOACs were about the same age and weight compared to standard anticoagulation group. Among all diagnosis categories, patients with active cancer were less likely to be prescribed low dose DOACs (HR 0.56; 95%CI 0.42-0.73; P&lt;0.001), while low dose DOACs prescription was more likely in patients with pulmonary embolism (HR 1.45; 95%CI 1.11-1.89; P=0.007). The median months to start a low dose DOAC after completing the 3 months was 3.1 months with standard deviation of 6.6 months and interquartile range 2.8 months. There was no statistically significant association in the likelihood of going to a low dose group in relation to VTE recurrence (HR 1.36; 95%CI 0.42-4.45; P=0.61) or major bleeding (HR 0.59; 95%CI 0.08-4.37; P=0.61). However, transitioning to low dose DOAC was associated with reduced mortality (HR 0.53; 95%CI 0.35-0.80; P=0.003). Also, patients on low dose DOACs were more likely to have a CRNMB (HR 2.76; 95%CI 1.15-6.62; P=0.02). Conclusion: In this study of patients continuing anticoagulation past 3 months for an initial acute venous thromboembolic event, transitioning to low dose DOACs was not associated with any statistically significant association with VTE recurrence or major bleeding. However, mortality was lower and CRNMB was higher in this unadjusted analysis. Our results show that physicians are not always waiting until 6 months to transition to low doses and low doses are being utilized in cancer patients. Further research is needed to better understand the higher risk for CRNMB identified in this group. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.

Background:There is limited published data on the association between malignancy and the location of venous thromboembolism (VTE) in the body. Aims:Assess the location of VTE in the body in patients with active cancer and compare these results in patients without malignancy. Methods:Consecutive patients enrolled in the Mayo Clinic VTE Registry between March 1, 2013 and November 30, 2019 for acute VTE were followed prospectively. Anatomical site of thrombosis and malignancy status were recorded. Patient outcomes were assessed in person, by mailed questionnaire, or by a scripted phone interview. Active cancer was defined as treatment for malignancy within the last six months or not yet in remission. Results:During the study period there were 2,798 patients with acute VTE (1256 with and 1542 without active cancer). Pulmonary emboli were more common in patients with active cancer compared to patients without cancer (49.5% vs. 39.7%, p&lt;0.001). Upper extremity deep vein thrombosis (11.4 % vs. 7.7%, p&lt;0.001), renal vein thrombi (1.4% vs. 0.2%, p&lt;0.001) and splanchnic vein thrombi (9.3% vs. 6.0%, p=0.001) were all more common in patients with active cancer compared to patients without cancer. Conclusion:Compared to those without malignancy, patients with active cancer were more likely to have pulmonary emboli, upper extremity deep vein thrombosis, renal vein thrombi, and splanchnic vein thrombi. Disclosures No relevant conflicts of interest to declare.

Abstract Objectives To investigate the association of extremes in bodyweight (EBW) and outcomes in patients with acute venous thromboembolism (VTE). Recurrent VTE, major bleeding, and clinically relevant non‐major bleeding were compared between patients with bodyweight <60 kg, 60‐120 kg, and >120 kg. Methods Consecutive patients enrolled in the Mayo Clinic VTE Registry (03/28/2013‐8/31/2019) with acute VTE were followed prospectively. Patient status was assessed in person, by mailing a written questionnaire, or by a scripted phone interview. Results Among 2577 patients with weight ranging from 27.0 kg to 263.2 kg, 2123 (82%) had a bodyweight between 60 and 120 kg, 223 (8.7%) had bodyweight < 60 kg, and 230 (8.9%) had bodyweight >120 kg. Patients with bodyweight <60 kg treated with DOACs had higher 3‐ and 6‐month incidence of major bleeding compared to the bodyweight 60‐120kg group (4.4% vs 1.1%, P = .03, and 4.4% vs 1.4%, P = .05, respectively). Patients with bodyweight >120 kg and cancer on rivaroxaban had higher VTE recurrence compared to bodyweight 60‐120kg group ( P = .01). Conclusions Treatment of acute VTE is associated with a higher incidence of bleeding in patients with bodyweight <60 kg. A higher VTE recurrence rate occurred only in cancer patients with bodyweight >120 kg on rivaroxaban.

AbstractRandomized controlled trials leading to the approval of apixaban and rivaroxaban for venous thromboembolism (VTE) did not include patients with upper extremity deep vein thrombosis (UE‐DVT). We sought to evaluate the safety and effectiveness of rivaroxaban and apixaban for the treatment of acute UE‐DVT. Consecutive patients with VTE enrolled into the Mayo Clinic VTE Registry, between March 1, 2013 and December 31, 2019, were followed prospectively. Clinical, demographic and imaging data were collected at the time of study recruitment. Patients with a diagnosis of acute UE‐DVT who received rivaroxaban, apixaban, LMWH or warfarin were included. Recurrent VTE, major bleeding, clinical‐relevant non‐major bleeding (CRNMB), and death were assessed at 3‐month intervals. During the study period, 210 patients with acute UE‐DVT were included; 63 were treated with apixaban, 39 with rivaroxaban, and 108 with LWMH and/or warfarin. Overall 51% had catheter‐associated UE‐DVT, 60% had a diagnosis of malignancy, and 14% had concurrent pulmonary embolism. Malignancy was more common in patients treated with LMWH/warfarin (67% vs 52%, P = .03). At 3 months of follow up, one (0.9%) recurrent VTE occurred in a patient treated with LMWH/warfarin and one (1.0%) patient treated with apixaban or rivaroxaban (P = .97). Major bleeding occurred in three patients treated with LMWH/warfarin, and in none of those treated with apixaban or rivaroxaban (P = .09). Clinical‐relevant non‐major bleeding occurred in one patient (0.9%) treated with LWMH/warfarin and two patients (2.0%) treated with apixaban or rivaroxaban (P = .53). Treatment of UE‐DVT with apixaban or rivaroxaban appears to be as safe and effective as LMWH/warfarin.

Background: Randomized controlled trials leading to the approval of apixaban and rivaroxaban for venous thromboembolism (VTE) did not include patients with UE-DVT. Limited observational data has been published on outcomes in this setting and no direct comparison to traditional anticoagulation has been performed. Objective: Evaluate the safety and effectiveness of rivaroxaban and apixaban for the treatment of acute UE-DVT compared to low-molecular weight (LWMH) and warfarin. Methods: Consecutive patients with VTE were enrolled into the Mayo Clinic VTE Registry, between March 1, 2013 and July 22, 2019, were followed prospectively. Clinical, demographic and imaging data were collected at the time of study recruitment. Patients with a diagnosis of acute UE-DVT who received either rivaroxaban, apixaban, LMWH or warfarin within the first 14 days after diagnosis and who completed at least 3 months of anticoagulant therapy or had an outcome event in that period were included into the analysis. Recurrent VTE, major bleeding, clinical relevant non-major bleeding (CRNMB), and death were assessed at 3 months, in person whenever feasible, or by mailing a written questionnaire or a scripted phone interview. The study was approved by Mayo Clinic Institutional Review Board. Results: One hundred and thirty-four patients with acute UE-DVT were included. Forty-one were treated with apixaban, 32 with rivaroxaban, and 61 with LWMH and/or warfarin. The mean age was 58.3 years, mean BMI was 28.2, and 59% were male (Table 1). Patients treated with LMWH / warfarin were older (61.3 vs 55.8, p=0.04) and had a lower BMI (27.1 vs 29.0, p=0.0496). Twenty-six (19%) patients had catheter-associated UE-DVT, 93 (69.4%) had a diagnosis of malignancy, and 16 (11.9%) had concurrent pulmonary embolism, which were similar between groups. More patients on apixaban /rivaroxaban were receiving chemotherapy (53.4% vs 47.5%, p=0.04) and had recent surgery (13.7% vs 3.3%, p=0.04) compared to LMWH / warfarin. At 3 months of follow up, 1 recurrent VTE occurred in patients treated with LMWH /warfarin and none of those treated with apixaban /rivaroxaban (p=0.27). Major bleeding occurred in 2 patients treated with LMWH /warfarin and in none of those treated with apixaban /rivaroxaban (p=0.12). CRNMB occurred in 1 patient treated with LWMH /warfarin and 5 patients treated with apixaban / rivaroxaban (p=0.15). Two of the CRNMBs occurred with rivaroxaban and 3 occurred with apixaban. Death occurred in 5 patients treated with LMWH /warfarin and in none of the apixaban /rivaroxaban treated patients (p=0.01). Conclusion: This single institution prospective study adds to the limited experience with apixaban and rivaroxaban for acute UE-DVT. Treatment of UE-DVT with rivaroxaban and apixaban appears to be as safe and effective as LMWH/warfarin after 3 months of anticoagulation. Disclosures McBane: BMS: Research Funding.

Background: Incidental pulmonary embolism (PE) is not infrequently found on CT scans with highest incidence reported in patients with cancer. It is unclear whether patients with symptomatic pulmonary embolism (iPE) have different clinical profile or outcomes compared to patients with symptomatic PE (sPE) and whether this is affected by the presence or type of malignancy. Objective: Compare baseline characteristics of patients diagnosed with iPE to patients with sPE with attention to cancer-specific risk factors as well as evaluate clinical outcomes. Methods: Consecutive patients enrolled in the Mayo Thrombophilia Clinic VTE Registry between March 1, 2013 and December 31st, 2018 with PE were followed prospectively. Outcomes of recurrent venous thromboembolism (VTE), major bleeding, clinically relevant non-major bleeding (CRNMB) and mortality data were collected every 3 months. Clinical outcomes were analyzed with specific focus on patients with cancer. Information was collected and managed using REDCap (Research Electronic Data Capture) and data analysis was performed using SAS software (SAS Institute Inc., Cary, North Carolina). Results: Out of a total of 1033 patients with PE in VTE registry, there were 655 patients with PE (284 with incidental and 363 symptomatic) who completed at least 3 months of anticoagulation and were started on treatment within 14 days of diagnosis. Apixaban was used in 220 (34 %), Rivaroxaban 175 (27 %), Enoxaparin 179 (27%), and Warfarin in 81 (12 %) patients. Overall cancer was present in 61% of patients and was more common in patients with iPE compared to sPE (80.2% vs 45.2%, p<0.001). Patients with iPE were less likely to have previous VTE (8.2% vs 25.5%, p< 0.0001) and tended to have lower BMI (mean 28.8 vs 31.4, p<0.0001) Characteristics of the subgroup of only cancer patients with PE are summarized in the Table. Of note, pancreatic and GI cancers were more common in patients with iPE. There were no differences in recurrent VTE, major bleeding and CRNMB in patients with iPE compared to sPE. This also held true for patients with underlying malignancies. Mortality rates were significantly higher in all patients with iPE even when adjusting for presence of malignancy (p=0.03). When adjusting for presence of metastatic malignancy though the difference was no longer present (p=0.33). Conclusion: Patients with iPE were more likely to have an underlying malignancy, potentially due to higher likelihood of undergoing staging imaging studies. Additionally, patients with iPE more often had metastatic disease which was associated with higher mortality. Recurrent VTE and bleeding outcomes were similar in patients with iPE and sPE, this was independent of the presence of underlying malignancy. Disclosures McBane: BMS: Research Funding.

Abstract Background: Randomized control trials (RCT) have examined the safety and efficacy of direct oral anticoagulants (DOACs) compared to dalteparin in patients with cancer-associated thrombosis (CAT). Increased major bleeding (MB) was seen with edoxaban and increased clinically relevant non-major bleeding (CRNMB) was seen with rivaroxaban and there has been specific concern about increased risk of bleeding among patients with gastrointestinal malignancies (GIM). Results from RCTs comparing apixaban to dalteparin in CAT are pending. Objective: Using the Mayo Clinic VTE registry, we examined the rates of MB, CRNMB, and overall bleeding (MB + CRNMB) in patients with GIM treated with anticoagulation for CAT. Methods: Consecutive patients treated for CAT were enrolled into Mayo Clinic VTE Registry between March 1, 2013 and July 27, 2018 and were followed prospectively for safety and efficacy. Clinical, demographic and imaging data were collected from each participant at the time of study recruitment. Cancer type, stage, and treatment with chemotherapy were recorded. Major and CRNMB events were evaluated at 3-month intervals. Clinical status was assessed by written questionnaire in subjects unable to return at 3 months. Unreturned questionnaires were followed up with a scripted phone interview. The study was approved by Mayo Clinic Institutional Review Board. Results: In the 535 subjects in the registry with CAT, the mean age (64.6 vs. 62.8 years), mean BMI (28.4 vs. 28.8), and percent female (46.4% vs 40.6%) were numerically similar between DOAC and LMWH treatment groups (Table 1). Metastatic disease was present in 53.6% and 60.2% and chemotherapy was being administered in 66.5% and 71.2% of DOAC and LMWH treated patients, respectively. Thrombocytopenia (<100x109/L) at initiation of anticoagulation was present in 6.8% of DOAC treated and 7.5% of LMWH treated patients. Among all cancer patients, 110 (21%) patients had a GIM, 58 (53%) were treated with LWMH and 52 (47%) were treated with a DOAC (42% rivaroxaban or 58% apixaban). In all CAT, the rate of MB was similar in DOAC versus LMWH treated patients (7.8 vs. 5.4 per 100 person-years; HR 1.48, 95% CI 0.72-3.05; Table 2). The rate of CRNMB however, was significantly increased in the DOAC patients compared to LMWH treated patients (6.18 vs. 0.44 per 100 person-years; HR 14.7, 95% CI 1.92, 112.26). In the sub-group of patients with GIM, the rate of MB was non-significantly higher in the DOAC versus LMWH treated patients (11.1 vs. 3.9 per 100 person-years; HR 2.90, 95% CI 0.57, 14.73). In contrast to the overall CAT group, the rate of CRNMB was similar in the DOAC compared to LMWH treated patients (2.10 vs. 1.92 per 100 person-years; HR 1.18, 95% CI 0.07, 20.21). In GIM patients, apixaban compared to rivaroxaban had a numerically higher, but non-significant, rate of major bleeding (23.98 vs. 3.50 per 100 person-years; HR 4.0, 95% CI 0.54-29.87). In the overall group of CAT, the risk of major bleeding was similar between apixaban and rivaroxaban (9.51 vs. 6.77 per 100 person-years). Conclusion: In our registry of subjects with CAT, we identified a significantly increased rate of CRNMB and overall bleeding, but not MB with the use of DOACs. In our data, GIM alone does not appear to account for the increased bleeding risk seen in CAT with DOACs, as we demonstrated no significant increase in major, CRNMB, or overall bleeding compared to LMWH. Direct comparison between apixaban and rivaroxaban was limited by sample size and number of events. Disclosures No relevant conflicts of interest to declare.