Antithrombotic therapy in lower extremity peripheral artery disease patients with venous thromboembolism: a nationwide cohort study

Background: Antithrombotic therapy (ATT) is recommended for patients with symptomatic lower extremity peripheral arterial disease (PAD). Optimal management of "breakthrough" venous thromboembolic events (VTEs) in these patients remains unclear. This study aims to describe current ATT prescription patterns in PAD patients before, during, and after VTE (treatment) and subsequent clinical outcomes. Methods: Using Dutch nationwide data, this cohort study identified patients with a reimbursement code for PAD between 2013 and 2021. Within this source population, patients with an International Classification of Diseases-10 code for VTE were identified and followed from VTE date until end-of-study date or death, whichever occurred first. ATT prescriptions, determined from pharmacy records, were mapped in 3 timeframes: 3 months before VTE, during VTE treatment, and 4 to 12 months after VTE. Results: Patients with PAD ( = 1866) and a concurrent VTE were included, with a mean age of 71.7 years and a median survival of 3.8 years. Before the VTE, 64% used antiplatelet therapy only, in contrast to 12% after VTE treatment. During the VTE treatment period, direct oral anticoagulants were the most frequently dispensed ATT type (40%), whereas 27% received anticoagulation plus antiplatelet therapy during this time. The one-year cumulative incidences of arterial thromboembolic events and clinically relevant bleedings were 6.1% (95% CI: 4.9-7.3) and 1.8% (95% CI, 1.2-2.4), respectively. Conclusion: Immediate treatment of VTE and long-term ATT use in PAD patients were heterogeneous in our cohort. A substantial proportion of patients had prescriptions for both antiplatelet therapy and anticoagulation during the VTE treatment period. Our findings highlight the need for consensus on this complex clinical dilemma.