Abstract
Background Several observational studies have reported the rate of venous and arterial thrombotic events in patients infected with COVID-19, with conflicting results. The aim of this study was to estimate the rate of thrombotic and bleeding events in hospitalized patients diagnosed with Coronavirus disease 2019 (COVID-19). Methods This was a multicenter study of 636 patients admitted between 20 March 2020 and 31 May 2020 with confirmed COVID-19 in four hospitals. Results Over a median length of stay in the non-ICU group of 7 days and of 19 days in the ICU group, twelve patients were diagnosed with Venous thromboembolism (VTE) (1.8 %) (95 % CI, 1.1-3). The rate in the non-ICU group was 0.19 % (95 % CI, 0.04-0.84), and that in the ICU group was 10.3 % (95 % CI, 6.4-16.2). The overall rate of arterial event is 2.2 % (95 % CI, 1.4-3.3). The rates in the non-ICU and ICU groups were 0.94 % (95 % CI, 0.46-0.1.9) and 8.4 % (95 % CI, 5.0-14.0). The overall composite event rate was 2.9 % (95 % CI, 2.0-4.3). The composite event rates in the non-ICU and ICU groups were 0.94 % (95 % CI, 0.46-0.1.9) and 13.2 % (95 % CI, 8.7-19.5). The overall rate of bleeding is 1.7 % (95 % CI, 1.0-2.8). The bleeding rate in the non-ICU group was 0.19 % (95 % CI, 0.04-0.84), and that in the ICU group was 9.4 % (95 % CI, 5.7-15.1). The baseline D-dimer level was a significant risk factor for developing VTE (OR 1.31, 95 % CI, 1.08-1.57, p = 0.005) and composite events (OR 1.32, 95 % CI, 1.12-1.55, p = 0.0007). Conclusions In this study, we found that the VTE rates in hospitalized patients with COVID-19 might not be higher than expected. In contrast to the risk of VTE, we found a high rate of arterial and bleeding complications in patients admitted to the ICU. An elevated D-dimer level at baseline could predict thrombotic complications in COVID-19 patients and may assist in the identification of these patients. Given the high rate of bleeding, the current study suggests that the intensification of anticoagulation therapy in COVID-19 patients beyond the standard of care be pursued with caution and would best be evaluated in a randomized controlled study.