Anticoagulation in atrial fibrillation: NOAC's the word

Shorter hospital stays in epistaxis patients with atrial fibrillation when taking rivaroxaban or apixaban versus phenprocoumon

Patients taking oral anticoagulants (OACs) currently represent one-third of all patients treated for epistaxis and an upward trend is expected. New direct oral anticoagulants (DOACs) have been on the market for approximately 10 years. DOACs are favoured over Vitamin K-Antagonists (VKAs) in the current guidelines. There are barely studies that investigate the impact of DOACs on patients with epistaxis. A retrospective study was performed analysing all patients who had stationary treatment for epistaxis from 01.01.2011 to 01.01.2018 in a tertiary care centre. In a total of 466 patients, 46.1% were on OACs. The main indication was atrial fibrillation (AF, 67.4%).The number of DOACs taken surpassed that of the VKAs during the past 2 years. The length of hospital stay was significantly longer in the phenprocoumon group (3 ± 0.2 days) in comparison to both the rivaroxaban (2.3 ± 0.1) and the apixaban (2.2 ± 0.1) groups (p = 0.005). Posterior epistaxis occurred more frequently in the phenprocoumon group (10.8%) than in the rivaroxaban (0%) and apixaban (0%) groups (p = 0.03). A correlation between CHA₂DS₂-VASc score (risk score for apoplexy in patients with AF, p = 0.01), HAS-BLED score (score for assessment of major bleeding in patients taking anticoagulants with AF, p = 0.006), and length of hospital stay (p = 0.002) with recurrence of epistaxis was found. Shorter hospital stays and exclusively anterior bleeding was noted in AF patients taking rivaroxaban and apixaban, whereas AF patients taking phenprocoumon stayed in hospital longer and had more posterior bleeding.

Cost-effectiveness of edoxaban compared to warfarin for the treatment and secondary prevention of venous thromboembolism in the UK

Background: Venous thromboembolism (VTE), which includes pulmonary embolism (PE) and deep vein thrombosis (DVT), is the third most common acute cardiovascular disease and represents an important burden for patients and payers. Objective: The aim was to estimate the cost-effectiveness of edoxaban, a non-VKA oral anticoagulant vs. warfarin, the currently most prescribed treatment for VTE in the UK. Study design: A Markov model was built using data from the Hokusai-VTE randomised controlled trial to estimate the lifetime costs and quality-adjusted life years (QALYs) in patients with VTE treated with edoxaban or warfarin over a lifetime horizon, from the UK National Health Services perspective. The model included VTE recurrences, VTE-related complications (post-thrombotic syndrome and chronic thromboembolic pulmonary hypertension), and several types of bleeds associated with anticoagulation treatment. Patients were treated during a period of 6 months after the first VTE event, followed by flexible treatment duration (from 6 months to lifetime) after recurrence, i.e., tertiary prevention. Results: Edoxaban was found dominant vs. warfarin with 0.033 additional QALY and £55 less costs. The reduction of patient management costs, specifically monitoring costs, outweighed the higher drug costs. Edoxaban was dominant in all subgroups (index DVT only, all PE cases (PE with or without DVT), PE without DVT and PE with DVT). Cost-savings ranged from £54 to £81 while additional QALYs ranged from 0.031 to 0.046. Edoxaban was found dominant in 88.6% of cases and cost-effective in additional 10.9% of cases considering a £20,000 threshold in the probabilistic sensitivity analysis. Conclusion: Edoxaban may improve patients' quality of life in a lifetime horizon without additional costs for the healthcare system due to lower bleeding risk and no monitoring cost compared to warfarin.

Anticoagulant effect and safety assessment of an aqueous extract of Pseudocedrela kotschyi (Schweinf.) harms and Adenia cissampeloides (Planch. Ex Hook.) harms

BACKGROUND

Currently available therapeutic options for thromboembolic disorders are often very expensive and are associated with unfavorable side effects.

AIM

To establish the anticoagulant effect and safety profile of an extract made from of the root bark of Pseudocedrela kotschyi (Schweinf.) Harms and the aerial part of Adenia cissampeloides (Planch. ex Hook.) Harms (PAE).

MATERIALS AND METHODS

PAE (0.5-2.0 g/L) effect on prothrombin time (PT) and activated partial thromboplastin time (aPTT) were evaluated on whole blood drawn from the marginal ear vein of New Zealand White rabbits. Effect of PAE (250-2000 mg/kg) on bleeding time (BT) and clotting time (CT) in Sprague-Dawley rats were also assessed. Histopathological, hematological, and liver function studies were also carried out to assess the safety for use of PAE (250-2000 mg/kg).

RESULTS

PAE had no significant effect (P > 0.05) on PT, but resulted in a significant increase (P ≤ 0.05-0.0001) in aPTT. The PAE treatment resulted in a significant increase (P ≤ 0.05-0.0001) in BT and CT in vivo compared with control. Safety studies indicated no deaths with PAE treatment with hematological and liver function tests being normal. Histological studies revealed pathological changes in the liver at a PAE treatment dose of 2000 mg/kg but all doses had no detrimental effect on kidney and stomach tissue. The no-observed-adverse-effect-level was <2000 mg/kg when given orally.

CONCLUSION

PAE has anticoagulant effect in vitro and is safe to use at oral doses <2000 mg/kg.