Safety outcomes of direct oral anticoagulants in older adults with atrial fibrillation: a systematic review and meta-analysis of (subgroup analyses from) randomized controlled trials.

Balancing stroke prevention and risk of bleeding in patients with atrial fibrillation (AF) is challenging. Direct oral anticoagulants (DOACs) are by now considered standard of care for treating patients with AF in international guidelines. Our objective was to assess the safety of long-term intake of DOACs in older adults with AF. We included RCTs in elderly (≥ 65 years) patients with AF. A systematic search in MEDLINE and EMBASE was performed on 19 April 2022. For determination of risk of bias, the RoB 2 tool was applied. We pooled outcomes using random-effects meta-analyses. The quality of evidence was assessed using GRADE. Eleven RCTs with a total of 63,374 patients were identified. Two RCTs compared apixaban with either warfarin or aspirin, four edoxaban with either placebo, aspirin, or vitamin K antagonists (VKAs), two dabigatran with warfarin and three rivaroxaban with warfarin. DOACs probably reduce mortality in elderly patients with AF (HR 0.89 95%CI 0.77 to 1.02). Low-dose DOACs likely reduce bleeding compared to VKAs (HR ranged from 0.47 to 1.01). For high-dose DOACS the risk of bleeding varied widely (HR ranged from 0.80 to 1.40). We found that low-dose DOACs probably decrease mortality in AF patients. Moreover, apixaban and probably edoxaban are associated with fewer major or clinically relevant bleeding (MCRB) events compared to VKAs. For dabigatran and rivaroxaban, the risk of MCRB varies depending on dose. Moreover, subgroup analyses indicate that in the very old (≥ 85) the risk for MCRB events might be increased when using DOACs.Registration: PROSPERO: CRD42020187876.

Risk of Incident Atrial Fibrillation and Subsequent Use of Oral Anticoagulants in Patients with Dementia.

BACKGROUND: Dementia and atrial fibrillation (AF) have many shared risk factors. Besides, patients with dementia are under-represented in randomized trials, and even if AF is present, oral anticoagulants (OACs) are not prescribed frequently. This study aimed to report the incidence of newly diagnosed AF in dementia patients, and the impacts of use of vitamin K antagonist (VKA; e.g., warfarin) and non-VKA OAC (NOACs) on stroke and bleeding outcomes. METHODS: Our study utilized the Taiwan National Health Insurance Research Database. A total of 554,074 patients with dementia were compared with 554,074 age- and sex-matched patients without dementia regarding the risk of incident AF. Among patients with dementia who experienced incident AF, the risks of clinical events of patients treated with warfarin or NOACs were compared with those without OACs (reference group). RESULTS: The risk of incident AF was greater for patients with dementia compared with those without (adjusted hazard ratio [aHR]: 1.054; 95% confidence interval [CI]: 1.040-1.068 for all types of dementia, aHR: 1.035; 95% CI: 1.020-1.051 for presenile/senile dementia, and aHR: 1.125; 95% CI: 1.091-1.159 for vascular dementia). Among patients with dementia and experienced incident AF, warfarin use was associated with a higher risk of ischemic stroke (aHR: 1.290; 95% CI: 1.156-1.440), intracranial hemorrhage (ICH; aHR: 1.678; 95% CI: 1.346-2.090), and major bleeding (aHR: 1.192; 95% CI: 1.073-1.323) compared with non-OACs. NOAC use was associated with a lower risk of ischemic stroke (aHR: 0.421; 95% CI: 0.352-0.503) and composite risk of ischemic stroke or major bleeding (aHR: 0.544; 95% CI: 0.487-0.608) compared with non-OACs. These results were consistent among the patients after the propensity matching. CONCLUSION: In this large nationwide cohort, the risk of newly diagnosed AF was higher in patients with dementia (all dementia, presenile/senile dementia, and vascular dementia) compared with those without dementia. For patients with dementia who experienced incident AF, NOAC use was associated with a better clinical outcome compared with non-OAC. Patients with dementia require a holistic approach to their care and management, including the use of NOACs to reduce the risks of clinical events.

Clinical Outcomes of Direct Oral Anticoagulants vs Warfarin for Extended Treatment of Venous Thromboembolism.

Importance: Extending the duration of oral anticoagulation for venous thromboembolism (VTE) beyond the initial 3 to 6 months of treatment is often recommended, but it is not clear whether clinical outcomes differ when using direct oral anticoagulants (DOACs) or warfarin. Objective: To compare rates of recurrent VTE, hospitalizations for hemorrhage, and all-cause death among adults prescribed DOACs or warfarin whose anticoagulant treatment was extended beyond 6 months after acute VTE. Design, Setting, and Participants: This cohort study was conducted in 2 integrated health care delivery systems in California with adults aged 18 years or older who received a diagnosis of incident VTE between 2010 and 2018 and completed at least 6 months of oral anticoagulant treatment with DOACs or warfarin. Patients were followed from the end of the initial 6-month treatment period until discontinuation of anticoagulation, occurrence of an outcome event, health plan disenrollment, or end of the study follow-up period (December 31, 2019). Data were obtained from the Kaiser Permanente Virtual Data Warehouse and electronic health records. Data analysis was conducted from March 2022 to January 2023. Exposure: Dispensed prescriptions of DOACs or warfarin after a 6-month initial treatment for VTE. Main Outcomes and Measures: The primary outcomes were rates per 100 person-years of recurrent VTE, hospitalizations for hemorrhage, and all-cause death. Comparison of DOAC and warfarin outcomes were performed using multivariable Cox proportional hazards regression. Results: A total of 18 495 patients (5477 [29.6%] aged ≥75 years; 8973 women [48.5%]) with VTE who were treated with at least 6 months of anticoagulation were identified, of whom 2134 (11.5%) were receiving DOAC therapy and 16 361 (88.5%) were receiving warfarin therapy. Unadjusted event rates were lower for patients receiving DOAC therapy than warfarin therapy for recurrent VTE (event rate per 100 person-years, 2.92 [95% CI, 2.29-3.54] vs 4.14 [95% CI, 3.90-4.38]), hospitalizations for hemorrhage (event rate per 100 person-years, 1.02 [95% CI, 0.66-1.39] vs 1.81 [95% CI, 1.66-1.97]), and all-cause death (event rate per 100 person-years, 3.79 [95% CI, 3.09-4.49] vs 5.40 [95% CI, 5.13-5.66]). After multivariable adjustment, DOAC treatment was associated with a lower risk of recurrent VTE (adjusted hazard ratio [aHR], 0.66; 95% CI, 0.52-0.82). For patients prescribed DOAC treatment, the risks of hospitalization for hemorrhage (aHR, 0.79; 95% CI, 0.54-1.17) and all-cause death (aHR, 0.96; 95% CI, 0.78-1.19) were not significantly different than those for patients prescribed warfarin treatment. Conclusions and Relevance: In this cohort study of patients with VTE who continued warfarin or DOAC anticoagulation beyond 6 months, DOAC treatment was associated with a lower risk of recurrent VTE, supporting the use of DOACs for the extended treatment of VTE in terms of clinical outcomes.

Association of type of oral anticoagulation with risk of bleeding in 45,114 patients with venous thromboembolism during initial and extended treatment-A nationwide register-based study.

BACKGROUND: Safety data for different anticoagulant medications in venous thromboembolism (VTE) are scarce, in particular for extended treatment. OBJECTIVES: To compare major bleeding rates depending on the choice of anticoagulation during initial (first 6 months) and extended treatment (6 months up to 5 years). METHODS: A nationwide register-based study including cancer-free patients with a first-time VTE between 2014 and 2020. Cox proportional hazards models were used to compare bleeding rates. RESULTS: We included 6558 patients on warfarin, 18,196 on rivaroxaban, and 19,498 on apixaban. At 6 months, 4750 (72.4%) remained on warfarin, 11,366 (62.5%) on rivaroxaban, and 11,940 (61.2%) on apixaban. During initial treatment, major bleeding rates were 3.86 (95% CI 3.14-4.58), 2.93 (2.55-3.31), and 1.95 (1.65-2.25) per 100 patient-years for warfarin, rivaroxaban, and apixaban, respectively, yielding adjusted hazard ratios (aHRs) of 0.89 (95% CI 0.71-1.12) for rivaroxaban versus warfarin, 0.55 (0.43-0.71) for apixaban versus warfarin, and 0.62 (0.50-0.76) for apixaban versus rivaroxaban. During extended treatment, major bleeding rates were 1.55 (1.19-1.91), 1.05 (0.85-1.26), and 0.96 (0.78-1.15) per 100 patient-years for warfarin, rivaroxaban, and apixaban, respectively, with aHRs of 0.72 (0.53-0.99) for rivaroxaban versus warfarin, 0.60 (0.44-0.82) for apixaban versus warfarin, and 0.85 (0.64-1.12) for apixaban versus rivaroxaban. Previous bleeding and increasing age were risk factors for bleeding both during initial and extended treatment. CONCLUSION: Apixaban had a lower bleeding risk than warfarin or rivaroxaban during initial treatment. During extended treatment, bleeding risk was similar for apixaban and rivaroxaban, and higher with warfarin.

Reduced dose direct oral anticoagulants compared with warfarin with high time in therapeutic range in nonvalvular atrial fibrillation.

Direct oral anticoagulants (DOACs) used in nonvalvular atrial fibrillation (NVAF) are dose-reduced in elderly and patients with impaired renal function. Only reduced dose dabigatran is concluded as having similar stroke risk reduction and lower risk of major bleeding than warfarin in the pivotal studies. In clinical practice, reduced dose is prescribed more often than expected making this an important issue. The objective of this study was to compare effectiveness and safety between reduced dose DOACs and high TTR warfarin treatment (TTR ≥ 70%) in NVAF. A Swedish anticoagulation registry was used in identifying eligible patients from July 2011 to December 2017. The study cohort consisted of 40,564 patients with newly initiated DOAC (apixaban, dabigatran, or rivaroxaban) (11,083 patients) or warfarin treatment (29,481 patients) after exclusion of 374,135 patients due to not being warfarin or DOAC naïve, not being prescribed reduced dose, having previous mechanical heart valve (MHV), or being under 18 years old. The median durations of follow up were 365, 419, 432 and 473 days for apixaban, dabigatran, rivaroxaban and warfarin, respectively. Warfarin TTR identified from Auricula was 70.0%. Endpoints (stroke and major bleeding) and baseline characteristics were collected from hospital administrative registers using ICD-10 codes. Cohorts were compared using weighted adjusted Cox regression after full optimal matching based on propensity scores. DOACs are associated with lower risk of major bleeding (HR with 95% CI) 0.85 (0.78-0.93), intracranial bleeding HR 0.64 (0.51-0.80), hemorrhagic stroke HR 0.68 (0.50-0.92), gastrointestinal bleeding HR 0.81 (0.69-0.96) and all-cause stroke HR 0.87 (0.76-0.99), than warfarin. Apixaban and dabigatran are associated with lower risk of major bleeding, HR 0.70 (0.63-0.78) and HR 0.80 (0.69-0.94), and rivaroxaban is associated with lower risk of ischemic stroke, HR 0.73 (0.59-0.96), with higher major bleeding risk, HR 1.31 (1.15-1.48), compared to warfarin. Apixaban is associated with higher all-cause mortality compared to warfarin, HR 1.12 (1.03-1.21). DOACs are associated with lower risk of major bleeding and all-cause stroke, than high quality warfarin treatment, with exception of rivaroxaban that carried higher risk of major bleeding and lower risk of stroke or systemic embolism. In this large observational registry-based NVAF cohort, DOACs are preferred treatment in patients with indication for DOAC dose reduction, even in a high TTR setting.

Comparison of the real-life clinical outcomes of warfarin with effective time in therapeutic range and non-vitamin K antagonist oral anticoagulants: Insight from the AFTER-2 trial.

BACKGROUND: It is unclear whether warfarin treatment with high time in therapeutic range (TTR) is as effective and safe as non-vitamin K antagonist oral anticoagulants (NOACs). It is crucial to compare warfarin with effective TTR and NOACs to predict long-term adverse events in patients with atrial fibrillation. AIMS: We aimed to compare the long-term follow-up results of patients with atrial fibrillation (AF) who use vitamin K antagonists (VKAs) with effective TTR and NOACs. METHODS: A total of 1140 patients were followed at 35 different centers for five years. During the follow-up period, the international normalized ratio (INR) values were studied at least 4 times a year, and the TTR values were calculated according to the Roosendaal method. The effective TTR level was accepted as >60% as recommended by the guidelines. There were 254 patients in the effective TTR group and 886 patients in the NOAC group. Ischemic cerebrovascular disease/transient ischemic attack (CVD/TIA), intracranial bleeding, and mortality were considered primary endpoints based on one-year and five-year follow-ups. RESULTS: Ischemic CVD/TIA (3.9% vs. 6.2%; P = 0.17) and intracranial bleeding (0.4% vs. 0.5%; P = 0.69), the one-year mortality rate (7.1% vs. 8.1%; P = 0.59), the five-year mortality rate (24% vs. 26.3%; P = 0.46) were not different between the effective TTR and NOACs groups during the follow-up, respectively. The CHA2DS2-VASC score was similar between the warfarin with effective TTR group and the NOAC group (3 [2-4] vs. 3 [2-4]; P = 0.17, respectively). Additionally, survival free-time did not differ between the warfarin with effective TTR group and each NOAC in the Kaplan-Meier analysis (dabigatran; P = 0.59, rivaroxaban; P = 0.34, apixaban; P = 0.26, and edoxaban; P = 0.14). CONCLUSION: There was no significant difference in primary outcomes between the effective TTR and NOAC groups in AF patients.

Drug Interactions Causing Warfarin Overdose in a Patient with Pancreatic Cancer: A Case Report.

Mistletoe, Viscum album, is a medicinal plant used in complementary medicine in oncology. Patients do not necessarily mention to their oncologist this phytotherapeutic treatment which may be responsible for unsuspected drug interactions. Some patients are adept at taking medicinal plants, a practice often unknown to health professionals who take care of them. This case reports drug interactions leading to bleeding secondary to warfarin overdose. A patient over 75 years of age was treated with nab-paclitaxel and gemcitabine as a first course for metastatic pancreatic adenocarcinoma (day 0). He was also treated with warfarin for atrial fibrillation. At day 3, he reported faintness and melena. At day 5, the biological assessment revealed anemia with hemoglobinemia of 5.1 g/dL and an international normalized ratio of 7.3, indicating vitamin K antagonist (VKA) overdose. Warfarin was discontinued and the patient received vitamin K supplementation and transfusions. The final diagnosis was an anemic syndrome due to gastrointestinal bleeding secondary to VKA overdose. Based on the chronology, a drug interaction between chemotherapy and warfarin was first suspected. Then, the patient interview found out that he self-medicated with subcutaneous injections of mistletoe extracts: 10 mg on day 0 and on day 2. Nab-paclitaxel can displace warfarin from its albumin binding sites and increase the free and active concentration of warfarin. Mistletoe extracts (V. album) are used as complementary medicine in oncology. Warfarin is predominantly metabolized in the liver by 1A2, 2C9, and 3A4 cytochrome P450 (CYP) isoforms. An inhibitor of these cytochromes prevents the degradation of warfarin into inactive metabolites, leading to accumulation or even overdose of this narrow therapeutic index VKA. Nab-paclitaxel and gemcitabine do not act on these cytochromes. V. album is a cytochrome P450 3A4 inhibitor which therefore probably led to an increase in exposure to warfarin. Thus, there are two pharmacokinetic hypotheses that may explain warfarin overdose: the displacement of warfarin from its albumin binding sites or the inhibition of CYP3A4 by mistletoe. This adverse drug event was reported to the Regional Pharmacovigilance Center of Strasbourg on June 30, 2021, and registered under the number ST20212767.

Proportion of Patients on Warfarin Therapy Who Are Eligible for Conversion to a Direct Oral Anticoagulant in the Setting of COVID-19.

BACKGROUND: Warfarin, a commonly prescribed anticoagulant, requires frequent lab monitoring. Lab monitoring puts patients at risk of COVID-19 exposure and diverts medical resources away from health care systems. Direct oral anticoagulants (DOACs) do not require routine therapeutic monitoring and are indicated first line for nonvalvular atrial fibrillation (NVAF) stroke prevention and venous thromboembolism (VTE) prevention/treatment. OBJECTIVE: The purpose of the study was to determine the proportion of patients who qualify for DOACs and assess for predictors of qualification. METHODS: This cross-sectional study investigated patients on warfarin managed by Michigan Medicine Anticoagulation Service. Direct oral anticoagulant eligibility criteria were established using apixaban, dabigatran, and rivaroxaban package inserts. Patient eligibility was determined through chart review. The primary outcome was the proportion of patients who qualify for DOACs based on clinical factors. Predictors of DOAC qualification were assessed. RESULTS: This study included 3205 patients and found 51.8% (n = 1661) of patients qualified for DOACs. Qualifying patients were older (71.9 vs 59.4 years, P < 0.0001) with a higher CHA2DS2 VASc (3.7 vs 3.4, P < 0.0007). The primary disqualifying factor was extreme weight, high and low. Accounting for a patient's sex and referral source, age > 65 (odds ratio [OR] = 1.9, P < 0.0001) and NVAF indication (OR = 5.6, P < 0.0001) were significant predictors for DOAC qualification. CONCLUSION AND RELEVANCE: Approximately 52% of patients on warfarin were eligible for DOACs. This presents an opportunity to reduce patient exposure to health care settings and health care utilization in the setting of COVID-19. Increased costs of DOACs need to be assessed.

Efficacy and Safety Assessment of Rivaroxaban for the Treatment of Cerebral Venous Sinus Thrombosis in a Chinese Population.

We aimed to investigate the efficacy and safety of rivaroxaban for acute and long-term management of cerebral venous sinus thrombosis (CVST). This study reviewed CVST-diagnosed patients admitted to the First Affiliated Hospital of Guangxi Medical University from January 2015 to December 2020. The primary outcome was a composite of recurrent thrombosis or major bleeding events. The secondary efficacy outcomes included a disease recovery time (DRT) presenting the time from admission to the endpoint as recovery (the modified Rankin scale [mRS] score [0-1]) within 30 and 90 days, and length of hospital stay (LHS). Patients treated with rivaroxaban (38) and warfarin (45) were enrolled in the final analysis. The primary outcome had no significant difference (5.3% vs 11.1%, P = .576) between the 2 groups. The secondary efficacy outcome regarding the median 30-d DRT was 17 days (95% confidence interval [CI], 14.6-19.4) in the rivaroxaban group, compared with 26.0 days (95% CI, 16.8-35.2) in the warfarin group (hazard ratio, 1.806; 95% CI, 1.051-3.103; log-rank P = .026). Two groups have a significant difference in LHS (P = .041). Patients with cerebral edema, intracerebral hemorrhage, and mild/moderate disability (admission mRS score [2-3]) treated with rivaroxaban recovered faster than those with warfarin (log-rank P < .05). Patients with cerebral edema, intracerebral hemorrhage, and mild/moderate disability treated with rivaroxaban had a shorter recovery time than those treated with warfarin within 1 month from admission, indicating that rivaroxaban a promising convenient therapy for CVST, helping them speedily restore social functions.

Comparison of real-world clinical and economic outcomes in patients receiving oral anticoagulants: A retrospective claims analysis.

BACKGROUND: Direct oral anticoagulants (DOACs) have become widely used for the prevention of stroke in nonvalvular atrial fibrillation (AF) and for the treatment of venous thromboembolism (VTE). Warfarin, the standard of care prior to DOACs, requires monitoring and dose adjustment to ensure patients remain appropriately anticoagulated. DOACs do not require monitoring but are significantly more expensive. We sought to examine real-world effectiveness and costs of DOACs and warfarin in patients with AF and VTE. OBJECTIVE: To examine clinical and economic outcomes. The clinical objectives were to determine the bleeding and thrombotic event rates associated with DOACs vs warfarin. The economic objectives were to determine the cost associated with these events, as well as the all-cause medical and pharmacy costs associated with DOACs vs warfarin. METHODS: This analysis was an observational, propensity-matched comparison of retrospective medical and pharmacy claims data for members enrolled in an integrated health plan between October 1, 2015, and September 30, 2020. Members who were older than 18 years of age with at least 1 30-day supply of warfarin or a DOAC filled within 30 days of a new diagnosis of VTE or nonvalvular AF were eligible for the analysis. Cox hazard ratios were used to compare differences in clinical outcomes, where paired t-tests were used to evaluate economic outcomes. RESULTS: After matching, there were 893 patients in each group. Among matched members, warfarin was associated with increased risk of nonmajor bleeds relative to apixaban (hazard ratio [HR] = 1.526; P = 0.0048) and increased risk of pulmonary embolism relative to both DOACs (apixaban: HR = 1.941 [P = 0.0328]; rivaroxaban: HR = 1.833 [P = 0.0489]). No statistically significant difference was observed in hospitalizations or in length of stay between warfarin and either DOAC. The difference-in-difference (DID) in total costs of care per member per month for apixaban and rivaroxaban relative to warfarin were $801.64 (P = 0.0178) and $534.23 (P = 0.0998) more, respectively. DID in VTE-related cost for apixaban was $177.09 less, relative to warfarin (P = 0.0098). DID in all-cause pharmacy costs for apixaban and rivaroxaban relative to warfarin were $342.47 (P < 0.0001) and $386.42 (P < 0.001) more, respectively. CONCLUSIONS: Warfarin use was associated with a significant decrease in total cost of care despite a significant increase in VTE-related costs vs apixaban. Warfarin was also associated with a significant increase in other nonmajor bleeds relative to apixaban, as well as a significant increase in pulmonary embolism relative to both DOACs. Warfarin was associated with a significant reduction in all-cause pharmacy cost compared with either DOAC. DISCLOSURES: The authors of this study have nothing to disclose.

Thromboembolism after treatment with 4-factor prothrombin complex concentrate or plasma for warfarin-related bleeding.

Limited data exist in large, representative populations about whether the risk of thromboembolic events varies after receiving four-factor human prothrombin complex concentrate (4F-PCC) versus treatment with human plasma for urgent reversal of oral vitamin K antagonist therapy. We conducted a multicenter observational study to compare the 45-day risk of thromboembolic events in adults with warfarin-associated major bleeding after treatment with 4F-PCC (Kcentra®) or plasma. Hospitalized patients in two large integrated healthcare delivery systems who received 4F-PCC or plasma for reversal of warfarin due to major bleeding from January 1, 2008 to March 31, 2020 were identified and were matched 1:1 on potential confounders and a high-dimensional propensity score. Arterial and venous thromboembolic events were identified up to 45 days after receiving 4F-PCC or plasma from electronic health records and adjudicated by physician review. Among 1119 patients receiving 4F-PCC and a matched historical cohort of 1119 patients receiving plasma without a recent history of thromboembolism, mean (SD) age was 76.7 (10.5) years, 45.6% were women, and 9.4% Black, 14.6% Asian/Pacific Islander, and 15.7% Hispanic. The 45-day risk of thromboembolic events was 3.4% in those receiving 4F-PCC and 4.1% in those receiving plasma (P = 0.26; adjusted hazard ratio 0.76; 95% confidence interval 0.49-1.16). The adjusted risk of all-cause death at 45 days post-treatment was lower in those receiving 4F-PCC compared with plasma. Among a large, ethnically diverse cohort of adults treated for reversal of warfarin-associated bleeding, receipt of 4F-PCC was not associated with an excess risk of thromboembolic events at 45 days compared with plasma therapy.

Health-related quality of life associated with warfarin and direct oral anticoagulants in venous thromboembolism.

INTRODUCTION: Venous thromboembolism (VTE) is commonly treated with oral anticoagulants, including warfarin or direct oral anticoagulants (DOACs). Although DOACs are associated with favorable treatment satisfaction, few studies have assessed whether quality of life differs between DOAC and warfarin users. MATERIALS AND METHODS: We invited adults enrolled in two California-based integrated health care delivery systems and with a history of VTE between January 1, 2015 and June 30, 2018 to complete a survey on their experience with anticoagulants. Health-related quality of life (QOL) was assessed using the RAND 36-item Short Form Health Survey (SF-36), which measures QOL in 2 general component scores (physical and mental). We used multivariable linear regression to compare mean QOL component scores between DOAC-users and warfarin-users, adjusting for patient and clinical characteristics. RESULTS: Overall, 2230 patients (43.1 % women and 31.8 % >75 years of age) taking anticoagulants answered at least 1 question on the SF-36, 975 taking DOACs and 1255 taking warfarin. After adjustment for patient-level factors, there were no significant differences in either physical component scores (39.2 v 38.3, p = 0.24) or mental component scores (48.5 v 49.0, p = 0.42) between DOAC and warfarin users. CONCLUSIONS: Health-related QOL did not significantly differ between DOAC and warfarin users with a history of VTE.

Effect of post-discharge pharmacist-led follow-up on drug treatment in patients with deep venous thrombosis in primary hospitals in China.

Warfarin and rivaroxaban were the two most commonly-used anticoagulant drugs for Deep venous thrombosis (DVT). The aim of this study was to explore the effects of post-discharge pharmacist-led follow-up on drug treatment in patients with DVT in primary hospitals from a pharmacological perspective. A total of 125 patients were recruited from July 2017 to June 2019 and randomized to either a control group or an intervention group. The control group was given routine medication guidance, clinical pharmacists followed up at 3 and 6 months after discharge. The intervention group was based on the control group and was followed up weekly for 6 months after discharge. For patients taking warfarin, the percentage of time in therapeutic range (TTR) and TTR>65% were significantly higher in the intervention group (p<0.05) and they also had less frequent dose changes. For patients taking warfarin or rivaroxaban, vascular ultrasonography showed better improvement rate in the intervention group (p<0.05). Pharmacist-led follow-up showed that the medication adherence (p<0.05) were significantly improved. There were lower risks of total and minor hemorrhage events and thrombosis events in the intervention group (p<0.05). Pharmacist-led follow-up not only reduced the risk of hemorrhage and thrombosis events, but also improved adherence to anticoagulation drugs.

A Cohort Study on the Safety and Efficacy of Warfarin and Rivaroxaban in Anticoagulant Therapy in Patients with Atrial Fibrillation Study.

Objective: To observe the safety and efficacy of warfarin and rivaroxaban in anticoagulation therapy in patients with atrial fibrillation (AF). Methods: A total of 96 patients with AF treated in our hospital from June 2019 to February 2021 were enrolled in this study. According to the different modes of drug administration, the patients were divided into the warfarin group and rivaroxaban group. Demographic and clinical data such as age, body weight, and previous drug use were collected. The blood routine, liver and kidney function, blood coagulation routine, and cardiac color ultrasound were accessed. The valvular atrial fibrillation and anticoagulant taboos were excluded, and the risk of embolism and bleeding was evaluated. Among them, 48 patients in the warfarin group were given warfarin once a day, and the international ratio (INR) was used to adjust the dose, and the INR was controlled between 2.0 and 3.0. In contrast, 48 patients in the rivaroxaban group received a fixed dose of rivaroxaban 20 mg or 15 mg once a day. After administration, regular telephone or outpatient follow-up was given once a month, to monitor patients' drug compliance and ask if there was bleeding, and to detect blood routine, urine routine, fecal routine+occult blood, and liver and kidney function. In addition, at the beginning of 3, 6, and 12 months of follow-up, each patient was given cardiac color Doppler ultrasound, peripheral vascular color ultrasound, and brain CT to determine whether there were mural thrombosis, stroke, and peripheral arterial thromboembolism. The INR attainment rate, coagulation index, thromboembolism, bleeding, and adverse reactions were compared between the two groups. Results: There was no significant difference in serum Dmurd and NT-proBNP levels between the two groups before treatment and 3, 6, and 9 months after treatment. There was no significant difference in the number of venous embolism, pulmonary embolism, cerebral embolism, and total embolism between the two groups (P > 0.05). There was no significant difference in the number of mild, moderate, and severe bleeding between the two groups (P > 0.05), but the total number of bleeding in the rivaroxaban group was lower than that in the warfarin group (P < 0.05). During the treatment, side effects such as nausea and vomiting, elevated transaminase, glutamyl transpeptidase, and diarrhea occurred between the two groups, and there was no significant difference in the number of adverse reactions between the two groups (P > 0.05). Conclusion: Compared with warfarin, rivaroxaban anticoagulant therapy has the same advantage in tolerance and prevention of thromboembolism in patients with AF, but rivaroxaban can effectively reduce the risk of bleeding in patients with AF.

Evaluation of safety and efficacy outcomes of direct oral anticoagulants versus warfarin in normal and extreme body weights for the treatment of atrial fibrillation or venous thromboembolism.

Despite evolving evidence, the use of direct oral anticoagulants (DOACs) in patients with extremes of body weight remains controversial. This study aimed to measure the impact of DOACs compared to warfarin on safety and efficacy outcomes in extreme body weight patients. This multi-center, health system, retrospective study examined the outcomes of patients with all body weights and extreme body weights prescribed a DOAC (rivaroxaban, apixaban, dabigatran, edoxaban) or warfarin for atrial fibrillation or venous thromboembolism over a 9-year period. The primary outcome was a composite of thromboembolism, symptomatic recurrent VTE, or severe bleeding; analyzed by pre-determined BMI cutoffs. A total of 19,697 patients were included in the study: 11,604 in the DOAC group and in the 8093 in the warfarin group. 295 patients were underweight and 9108 patients were pre-obese to obese class 3. After adjusting for potential confounders, warfarin patients had higher odds of experiencing the composite outcome compared to DOAC patients (OR 1.337, 95% CI 1.212-1.475). Additionally, obese patients were 24.6% more likely to experience the outcome compared to normal BMI patients. Adjusted modeling showed that warfarin patients experienced higher bleed rates compared to DOAC patients (OR 1.432, 95% CI 1.266-1.620). Obese patients were less likely to be diagnosed with a bleed (OR 0.749, 95% CI 0.658-0.854), and underweight patients were more likely to be diagnosed with a bleed (OR 1.522, 95% CI 1.095-2.115) compared to normal BMI patients. In conclusion, DOACs for atrial fibrillation or VTE in patients with extreme body weights appear safe and effective when compared to warfarin.

High versus low fixed-dose four factor-prothrombin complex concentrate for warfarin reversal in patients with intracranial hemorrhage.

BACKGROUND: Four-factor prothrombin complex concentrate 4F-PCC is the standard of care for warfarin reversal in patients with major bleed or requiring urgent surgery. Although the 4F-PCC dose is weight and international normalized ratio (INR) based, for practical purposes, a fixed-dose approach has been explored, especially for rapid reversal. We report our experience using two different fixed-dose 4F-PCC for warfarin reversal in patients presenting with intracranial hemorrhage (ICH). STUDY DESIGN AND METHODS: We completed a retrospective chart review comparing high (4000 units) versus low (2000 units) dose 4F-PCC by evaluating patient characteristics, laboratory data, and pre-and post-4F-PCC brain imaging. RESULTS: There was no significant difference between patient characteristics or INR correction (≤1.5) between the two groups. Eighty percent (12/15) of patients who received the low dose 4F-PCC had either improved or stable brain imaging as compared to 88% (14/16) of patients who received the high dose PCC. When the eight patients (4 from each arm of the study) who required neurosurgery were excluded, only two patients in each arm had worse imaging after 4F-PCC. CONCLUSION: There was no significant difference between the INR correction and the brain imaging changes in patients with an ICH who received either the high or the low fixed-dose 4F-PCC for warfarin reversal.

Association of Type of Oral Anticoagulant Dispensed With Adverse Clinical Outcomes in Patients Extending Anticoagulation Therapy Beyond 90 Days After Hospitalization for Venous Thromboembolism.

Importance: Guidelines for managing venous thromboembolism (VTE) recommend at least 90 days of therapy with oral anticoagulants. Limited evidence exists about the optimal drug for continuing therapy beyond 90 days. Objective: To compare having prescriptions dispensed for apixaban, rivaroxaban, or warfarin after an initial 90 days of anticoagulation therapy for the outcomes of hospitalization for recurrent VTE, major bleeding, and death. Design, Setting, and Participants: This exploratory retrospective cohort study used data from fee-for-service Medicare (2009-2017) and from 2 commercial health insurance (2004-2018) databases and included 64 642 adults who initiated oral anticoagulation following hospitalization discharge for VTE and continued treatment beyond 90 days. Exposures: Apixaban, rivaroxaban, or warfarin prescribed after an initial 90-day treatment for VTE. Main Outcomes and Measures: Primary outcomes included hospitalization for recurrent VTE and hospitalization for major bleeding. Analyses were adjusted using propensity score weighting. Patients were followed up from the end of the initial 90-day treatment episode until treatment cessation, outcome, death, disenrollment, or end of available data. Weighted Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% CIs. Results: The study included 9167 patients prescribed apixaban (mean [SD] age, 71 [14] years; 5491 [59.9%] women), 12 468 patients prescribed rivaroxaban (mean [SD] age, 69 [14] years; 7067 [56.7%] women), and 43 007 patients prescribed warfarin (mean [SD] age, 70 [15] years; 25 404 [59.1%] women). The median (IQR) follow-up was 109 (59-228) days for recurrent VTE and 108 (58-226) days for major bleeding outcome. After propensity score weighting, the incidence rate of hospitalization for recurrent VTE was significantly lower for apixaban compared with warfarin (9.8 vs 13.5 per 1000 person-years; HR, 0.69 [95% CI, 0.49-0.99]), but the incidence rates were not significantly different between apixaban and rivaroxaban (9.8 vs 11.6 per 1000 person-years; HR, 0.80 [95% CI, 0.53-1.19]) or rivaroxaban and warfarin (HR, 0.87 [95% CI, 0.65-1.16]). Rates of hospitalization for major bleeding were 44.4 per 1000 person-years for apixaban, 50.0 per 1000 person-years for rivaroxaban, and 47.1 per 1000 person-years for warfarin, yielding HRs of 0.92 (95% CI, 0.78-1.09) for apixaban vs warfarin, 0.86 (95% CI, 0.71-1.04) for apixaban vs rivaroxaban, and 1.07 (95% CI, 0.93-1.24) for rivaroxaban vs warfarin. Conclusions and Relevance: In this exploratory analysis of patients prescribed extended-duration oral anticoagulation therapy after hospitalization for VTE, prescription dispenses for apixaban beyond 90 days, compared with warfarin beyond 90 days, were significantly associated with a modestly lower rate of hospitalization for recurrent VTE, but no significant difference in rate of hospitalization for major bleeding. There were no significant differences for comparisons of apixaban vs rivaroxaban or rivaroxaban vs warfarin.

Safety and Effectiveness of Direct Oral Anticoagulants Versus Warfarin for Treating Left Ventricular Thrombus.

BACKGROUND: Patients with left ventricular thrombus are at high risk for ischemic stroke and systemic embolization. The mainstay of treatment is anticoagulation, but it remains unclear if direct-acting oral anticoagulants (DOACs) are a safe and effective treatment strategy compared to warfarin. We conducted a population-based retrospective cohort study to evaluate the effectiveness and safety of DOACs compared to warfarin in an integrated health system in the United States. METHODS: Consecutive patients with left ventricular thrombus on transthoracic echocardiogram from May 2010 to April 2020 were identified. Comparative effectiveness and safety of DOACs and warfarin were evaluated using multivariable Cox proportional hazard models and inverse probability of treatment weighting. RESULTS: Among 433 patients with left ventricular thrombus, 134 (30.9%) were treated with DOACs and 299 (69.1%) were treated with warfarin. Patients were followed for a median of 3.4 years. For the primary effectiveness outcome of ischemic stroke, systemic embolism, and transient ischemic attack, no significant difference was observed between use of DOACs compared to warfarin (adjusted hazard ratio [HR] of 0.75, 95% confidence interval [CI] 0.48-1.18, p = 0.21). For the primary safety outcome of intracranial hemorrhage, gastrointestinal bleeding, and other bleed requiring hospitalization, DOAC usage was associated with a lower risk of bleeding (HR 0.58, 95% CI 0.39-0.87, p = 0.0008). CONCLUSIONS: In this diverse population-based cohort of patients, DOAC treatment for left ventricular thrombus appears to be as safe and effective as warfarin treatment. These findings support the use of DOACs for patients with left ventricular thrombus.

Non-persistence to Oral Anticoagulation Treatment in Patients with Non-valvular Atrial Fibrillation in the USA.

BACKGROUND: Studies have shown that patients with non-valvular atrial fibrillation (NVAF) who discontinue oral anticoagulants (OACs) are at higher risk of complications such as stroke. OBJECTIVE: This analysis compared the risk of non-persistence with OACs among patients with NVAF. METHODS: Adult patients with NVAF who initiated apixaban, dabigatran, rivaroxaban, or warfarin were identified using 01JAN2013-30JUN2019 data from Centers for Medicare and Medicaid Services and four US commercial claims databases. Non-persistence was defined as discontinuation (no evidence of index OAC use for ≥ 60 days from the last days' supply) or switch to another OAC. Kaplan-Meier curves were generated to illustrate time to non-persistence along with cumulative incidences of non-persistence. Baseline and time-varying covariates were evaluated, and adjusted Cox proportional hazards models were used to evaluate non-persistence risk. RESULTS: In total, 363,823 patients receiving apixaban, 57,121 receiving dabigatran, 282,831 receiving rivaroxaban, and 317,337 receiving warfarin were included. Of these, 47-72% discontinued/switched OAC therapy within an average 9-month follow-up. Apixaban was associated with a lower risk of non-persistence than were dabigatran (hazard ratio [HR] 0.62; 95% confidence interval [CI] 0.61-0.62), rivaroxaban (HR 0.76; 95% CI 0.75-0.76), and warfarin (HR 0.74; 95% CI 0.74-0.75). Dabigatran was associated with a higher risk of non-persistence than were warfarin (HR 1.21; 95% CI 1.19-1.22) and rivaroxaban (HR 1.23; 95% CI 1.22-1.25), and rivaroxaban was associated with a lower risk of non-persistence than was warfarin (HR 0.98; 95% CI 0.97-0.98). Clinical events (stroke/systemic embolism and major bleeding [MB]) during follow-up were predictors of non-persistence (stroke HR 1.57; 95% CI 1.53-1.61; MB HR 2.96; 95% CI 2.92-3.00). CONCLUSION: In over one million patients with NVAF, our results suggest differences in anticoagulation treatment persistence across OAC agents, even after accounting for clinical events after OAC initiation. It is important for clinicians and patients to take these differences into consideration, especially as non-persistence to OAC therapy is associated with thromboembolic complications.

Effectiveness and Safety of Dabigatran in Atrial Fibrillation Patients with Severe Obesity: a Real-World Retrospective Cohort Study.

BACKGROUND: Direct oral anticoagulants such as dabigatran are the preferred anticoagulant in treating atrial fibrillation (AF) patients due to their effectiveness and safety. Whether this applies to severely obese patients needs to be determined. OBJECTIVE: To compare the effectiveness and safety of dabigatran with warfarin among AF patients with severe obesity. DESIGN: Retrospective cohort study. PARTICIPANTS: AF patients with a BMI >40kg/m2 or a weight >120kg receiving dabigatran or warfarin between 10/01/2010 and 12/31/2019 in a large integrated health system and followed through 08/01/2020. INTERVENTIONS: Not applicable. MAIN MEASURES: Primary effectiveness outcome was composite thromboembolism including transient ischemic attack, ischemic stroke, or systemic embolism. Primary safety outcome was composite bleeding including gastrointestinal bleeding, intracranial bleeding, or other bleeding. Secondary outcomes included the individual outcomes and all-cause mortality. Propensity score matching (PSM) was performed to create a 1:1 matched cohort and Cox proportional hazards model was used to estimate the hazard ratio (HR) of each outcome for dabigatran users compared to warfarin users. KEY RESULTS: A total of 6848 patients receiving either dabigatran or warfarin were identified. In a 1:1 matched cohort, dabigatran users had a HR of 0.71 (95% confidence interval (CI): 0.56-0.91) for composite thromboembolism, a HR of 1.24 (95%CI: 1.07-1.42) for composite bleeding, and a HR of 0.57 (95% CI: 0.45-0.71) for all-cause mortality when compared to warfarin users. CONCLUSIONS: Among AF patients with a BMI >40kg/m2 or a weight >120kg in a real-world clinical setting, dabigatran was effective in reducing the risk of thromboembolism and mortality but was associated with an increased risk of bleeding when compared to warfarin. Dabigatran may be a reasonable option for AF patients with severe obesity.