Risk of bleeding in pulmonary embolism patients concomitant with COVID-19 undergoing extended anticoagulation: A multicenter cohort study.

Introduction: The impact of Coronavirus disease 2019 (COVID-19) on clinical outcomes in pulmonary embolism (PE) patients receiving extended anticoagulation therapy is not fully understood. The study aimed to investigate the impact of the Omicron outbreak on patients with PE receiving extended anticoagulation therapy.

Materials And Methods: This prospective multicenter cohort study was conducted during the Omicron pandemic. Patients diagnosed with PE between January 1, 2016, and September 1, 2022, who were on extended anticoagulation therapy, were recruited. The study compared VTE recurrence and bleeding events between COVID-19 and non-COVID-19 patients, using the propensity score weighting with overlap weights (PSOW) method for the final analysis.

Results: A total of 521 patients with PE receiving extended anticoagulation therapy were enrolled. Patients suffering from COVID-19 had significantly higher bleeding rates (10.5 % vs 2.1 %, p = 0.001), with consistent results after PSOW (OR = 4.79, 95%CI [1.04-22.21], p = 0.045). No significant differences in VTE recurrence were observed between these two groups before and after weighting. During follow-up, 31 % of patients developed long COVID, with higher bleeding rates (14.6 % vs 3.5 %, p < 0.001). After PSOW, there was a significantly increased bleeding risk in patients with long COVID (HR = 3.29, 95%CI [1.28, 8.49]); Log-Rank test p < 0.001). Furthermore, a prior history of active malignancy (OR = 9.3; 95%CI [1.38, 59.98]), chronic kidney disease (OR = 13.98; 95%CI [1.59, 122.27]) and bleeding occurred during the acute phase of COVID-19 (OR = 23.73; 95%CI [5.20, 108.35]) were independent predictors of bleeding in patients with long COVID.

Conclusions: COVID-19 and long COVID are associated with an increased bleeding risk in PE patients undergoing extended anticoagulation therapy. This study emphasizes the need for close monitoring and optimization of anticoagulation strategies in PE patients.