Is Stopping Anticoagulation Too Risky?

FLORENCE, Italy — Should anticoagulant therapy be discontinued or continued in patients with unprovoked deep vein thrombosis (DVT)? This question was at the center of a debate between Francesco Dentali, MD, president of the Italian Federation of Associations of Hospital Doctors on Internal Medicine and professor of internal medicine at the University of Insubria in Varese, Italy, and Manuel Monreal, MD, PhD, director of the Chair for the Study of Thromboembolic Disease at the Universidad Católica San Antonio de Murcia, Murcia, Spain, and founder of the RIETE registry, the largest global database of patients with DVT.

During the 23rd European Congress of Internal Medicine (ECIM) 2025, held from 5 to 8 March, the two experts presented scientific evidence and clinical insights while arguing for and against continuing anticoagulation beyond 3-6 months in these patients. Both acknowledged that the boundaries between these two perspectives are often unclear, and that individualized treatment remains the best approach.

Evidence Favors Extended Anticoagulation: Dentali

Dentali opened the discussion with an overview of anticoagulant therapy in DVT, recalling that since the early 1990s, research has consistently demonstrated the need for at least 3 months of anticoagulation. Early studies showed that 3 months of treatment significantly reduces recurrence rates compared to a 4-week regimen, with no significant increase in major bleeding.

A comparison of 6-week vs 6-month treatment durations further reinforced the need for extended therapy, showing that recurrence rates were reduced by half in the 6-month treatment group (20.8% vs 10.3%).

The CHEST guidelines currently recommend a minimum of 3 months of anticoagulation, emphasizing that after this period, patients should be reassessed to determine whether continuing therapy is necessary.

What remains to be determined is whether and how to continue anticoagulation beyond 3-6 months. The debate highlights the need for careful patient evaluation to balance the risk for recurrence against the potential for bleeding complications.

• After discontinuing anticoagulant therapy, the 10-year recurrence risk in patients with unprovoked DVT or pulmonary embolism (PE) is approximately 50% compared with 20% in patients with transient risk factors. This suggests that unprovoked DVT may be considered a chronic disease.
• Meta-analyses indicate that the risk for venous thromboembolism (VTE) recurrence is significantly higher with short-term anticoagulant therapy (4-6 weeks) than with extended treatment (> 3 months).
• Although major bleeding is a concern, its incidence rate after prolonged anticoagulation with direct-acting oral anticoagulants (DOACs) is relatively low (1.2 per 100 person-years).
• Real-world data from the GARFIELD-VTE registry indicate that at 36 months, the risk for VTE recurrence exceeds that of major bleeding, favoring extended anticoagulant therapy in high-risk patients.
• Risk stratification models may help identify patients at low risk for recurrence who may safely discontinue anticoagulation therapy, although defining an optimal threshold for treatment cessation remains a challenge.
• The current CHEST guidelines recommend extended DOAC treatment for patients with DVT or DVT associated with persistent risk factors.
• The AMPLIFY-EXT trial demonstrated that a reduced dose of apixaban (2.5 mg twice daily) effectively prevents recurrence without increasing the risk for major bleeding.
• Risk assessment tools, such as the VTE-PREDICT risk score, help evaluate recurrence and bleeding risks for better decision-making.

Against Continuation: Monreal

• When deciding whether to continue or discontinue anticoagulation therapy, it is essential to consider not only the risk of bleeding during treatment but also the post-anticoagulation bleeding risk, which is not negligible.
• Analyses, including the RIETE registry data, show that the VTE-PREDICT score provides reasonable estimates but may underestimate the bleeding risk.
• Both VTE recurrence and bleeding risks should be considered when deciding on anticoagulant therapy for patients with VTE.
• Data from a RIETE registry-based study of over 8000 patients who discontinued anticoagulation after isolated DVT or PE confirmed that while recurrent DVT and PE were more common, bleeding episodes were often severe.
• The 30-day mortality rates were 0.4% for recurrent DVT, 4.6% for recurrent PE, and 24% for major bleeds.

Monreal declared no conflicts of interest. Dentali disclosed receiving conference funding from Bayer, Sanofi, Bristol Myers Squibb/Pfizer, Boehringer Ingelheim, Daiichi Sankyo, Alfa Wassermann, Eli Lilly and Company, and Sandoz.

Cristina Ferrario, a molecular biologist by training, holds a master’s degree in communication and health from the University of Milan, and in cancer genetics from the University of Pavia, Italy. After conducting research in molecular oncology, she has been involved in scientific journalism and medical writing for over 20 years.

This story was translated from Univadis Italy using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.