Bleeding risks with novel oral anticoagulants especially rivaroxaban versus aspirin: a meta-analysis

Background This pairwise meta-analysis determines the difference in bleeding risks associated with the use of novel oral anticoagulants (NOACs) and aspirin. Methods PubMed, the Cochrane Library database, clinicaltrial.gov, and related studies were searched for randomized control trials (RCTs) comparing NOAC and aspirin published between January 1, 2000 and May 10, 2021. The primary endpoint was intracranial hemorrhage (ICH). Results Eleven studies involving 57,645 patients were included. Compared to aspirin, rivaroxaban (5 mg/day) had a similar risk of ICH, major bleeding, and fatal bleeding; rivaroxaban (10 mg/day) had higher risks of gastrointestinal hemorrhage (OR: 1.41; 95% CI: 1.03–1.94; P = 0.032; I2 = 0%) and a similar risk of ICH, major bleeding, and fatal bleeding; and rivaroxaban (15–20 mg/day) had higher risks of ICH (OR: 3.21; 95% CI: 1.36–7.60; P = 0.008; I2 = 0%), major bleeding (OR: 2.64; 95% CI: 1.68–4.16; P < 0.001; I2 = 0%), and fatal bleeding (OR: 2.26; 95% CI: 1.25–4.08; P = 0.007; I2 = 0%) and a similar risk of gastrointestinal hemorrhage. Bleeding outcomes between other NOACs (apixaban and dabigatran etexilate) and aspirin were not different. Conclusions The bleeding risks associated with NOACs depend on drug type and dosage. For ≥15 mg/day of rivaroxaban, the risk of ICH was significantly higher than that with aspirin. However, further studies comparing dabigatran etexilate and apixaban versus aspirin are warranted to draw a definite conclusion.

The Novel Oral Anticoagulants (NOACs) for the Treatment of Cerebral Venous Thrombosis: A Case Study of 32 Vietnamese Patients

Background and Purpose: Cerebral venous thrombosis (CVT) is a rare cause of cerebral infarction with diverse clinical presentations and outcomes. Novel oral anticoagulants (NOACs) provide an alternative option of systemic anticoagulation in various thromboembolic conditions, but uncertainty exists over the use of NOACs among patients with CVT. We present our initial experience with the use of NOACs for CVT in Vietnam. Methods: We included consecutive patients diagnosed with CVT presenting to 115 People’s Hospital in Vietnam between May 2016 and July 2017 and who were treated with NOACs. Data on patient demographics, vascular risk factors, clinical presentations, and outcomes at 180 days follow-up were obtained and analyzed. Modified Rankin scale (mRS) scores on admission, at discharge, and 180 days were assessed. Recanalization was assessed using magnetic resonance venography at 180 days follow-up. Venous thrombo-embolism events were defined as primary outcome, while bleeding complications were defined as safety outcome. Results: Among 32 patients with CVT (72% females; mean age: 40 ± 9.7 years), 15 were treated with rivaroxaban and 17 with dabigatran. A common risk factor was the usage of oral contraception (70%) on presentation. The mean mRS score on admission was 3.1 points (± 1.4). At FUP (median 8.5 months, IQR 5.5-9.5), clinical outcome (mRS ≤ 1) was excellent in most patients. All patients had at least partial recanalization and half of them achieved complete recanalization at 180 days follow-up. There were no bleeding complications. Conclusion: NOACs may offer clinical benefits with minimal complications in the treatment of CVT. Further prospective assessment with randomized controlled studies is warranted.

Rivaroxaban Causing Thrombocytopenia in a Case of Deep Vein Thrombosis (DVT)

Novel oral anticoagulants (NOACs) are used as alternative to intravenous anticoagulants. It includes apixaban, dabigatran, rivaroxaban and edoxaban.1 Some of the complications induced by these drugs are gastrointestinal haemorrhage, cerebral haemorrhage and rarely thrombocytopenia. We present a rare case report of a selective factor Xa inhibitor rivaroxaban, which induced thrombocytopenia in a case of deep vein thrombosis (DVT) of right lower limb. Drugs commonly used to prevent embolization of systemic circulation are warfarin and novel oral anticoagulants, such as rivaroxaban and dabigatran.