PB0424 - Post thrombotic syndrome: quality of life and incidence in patients under treatment with direct oral anticoagulants.

Background: Post-thrombotic syndrome(PTS) is a disabling complication of venous thrombotic disease. It is still unclear wheter treatment with direct oral anticoagulants (DOACs) reduces the incidence of PTS compared to treatmen with vitamin K antagonist (vKA). There is no effective treatment strategy, but the use of compression stockings is recommended, with conflicting results.

Aims: The primary aim was to compare the incidence of PTS in DOACs vs warfarin, according also with the presence of thrombophilia. The second aim was to assess the quality of life of affected patients by investigating the role of compression stockings.

Methods: 538 patients with deep vein thrombosis of the lower limbs, evaluated at the Thrombotic and Hemorrhagic Diseases Unit of the University Hospital of Padua, between 2014 and 2020, were enrolled, treated with DOACs for at least 3 months and compared with a historical sample of 538 patients, referred to our centre, treated with vKA. The possible onset of PTS (Villalta criteria) was recorded in the following months. The quality of life was investigated through the VEINES questionnaire, recording also the use of elastic stockings.

Results: The Hazard ratio (HRa) was statistically significant for DOACs than vKA (HRa 2.49; 95% CI; 1.94-3.20), especially for rivaroxaban (HRa 2.68; 95% CI; 1.92-3.74). Thrombophilia was not statistically associated with the risk of PTS regardless of the type of anticoagulant used (p < 0.05). Symptoms most suffered were heaviness in the lower limbs (60%), severe limitation of social activities (25.7%). 46 (65.7%) patients reported a limited use of elastic stockings. Even with low compliance, more people reported an improvement of the symptoms (18.6%) than those who reported a worsening (5.7%).

Conclusion(s): DOACs reduce the incidence of PTS more than vKA, thrombophilia does not influence the risk. The graduated elastic compression improves the quality of life of patients with PTS, that is strongly affected by symptoms.