A multicenter cohort study of COVID-19 associated venous thromboembolism in admitted patients followed longitudinally 3-months after discharge

ABSTRACT

Background: The incidence of venous thromboembolism (VTE) in patients with COVID-19 during hospitalization and in the post-discharge setting has been reported with wide variability. Many studies have short follow-up, reported the early phase of the pandemic, or did not report bleeding or anticoagulant dosing. Aim(s) We determined the incidence of symptomatic VTE and bleeding in patients admitted to hospital for COVID-19 and their 3-month risk of VTE post-discharge. Method(s) All patients admitted for COVID-19 at 5 regional hospitals were identified between January 1 and December 31, 2020. Data were collected from their hospital admission and for a minimum of 3 months post-discharge. Re-admissions during this period were considered as post-discharge data of the index admission. Standard thromboprophylaxis for critical care and ward patients were enoxaparin 30 mg twice daily or 40 mg once daily. Post-discharge thromboprophylaxis was not given. Patient consent was waived by the institutional research ethics board. Result(s) A total of 565 patients were included. Baseline demographics are reported in Table 1. Median length-of- stay was 9.0 days (range 5-131). 178 patients (31.5%) required critical care support and 79 patients (14%) died during index admission. 25 patients (4.4%) had VTE during hospitalization, of which 17 occurred within first 2 weeks and none occurred in those on therapeutic anticoagulation. There were no fatal bleeds. 5 patients (0.88%) developed critical site bleeding. Patient characteristics, anticoagulant use and bleeding rates during hospitalization are reported in Table 2. Among 486 discharged patients, median length of follow-up was 163 days (range 3-600) 63.5% had at least 90 days of follow-up data and 18.7% were lost to follow-up. 5 patients (1.3%) had symptomatic VTE diagnosed within 3 months after discharge. Conclusion(s) The in-hospital incidence of VTE in COVID-19 was lower but post-discharge incidence was higher than other studies. Therapeutic anticoagulation appeared protective against symptomatic VTE. (Table Presented).