Comparison of Incidence of Venous Thromboembolism (VTE) to Baseline During the COVID-19 Pandemic in a Community-Based Healthcare System

Rationale: The SARS-CoV-2 virus responsible for COVID-19 is known to cause coagulopathy and thrombotic events in affected patients. In a recent meta-analysis, the rate of venous thromboembolism (VTE) in hospitalized COVID-19 patients was estimated to be about 17%. However, the incidence of VTE in COVID-19 is not clearly reported at the population level. We examined the incidence of VTE in COVID-19 at a population level in order to calculate incidence rates and make a comparison to rates from the same population in the previous year. Methods: We performed a retrospective analysis across a multi-center community-based hospital system for all adult patients (age ≥18 years) admitted with a positive COVID-19 test from March 1, 2020 to September 18, 2020. Patients were identified in the electronic medical record (EMR) using ICD10 codes for VTE (both pulmonary embolism and deep venous thrombosis). Chart review of the EMR was also used to obtain relevant demographic, clinical, and laboratory data. Patients with VTE confirmed by imaging studies were included. Incidence rates were calculated using total COVID-19 case count per county. The same methodology was then used to evaluate VTE from March 1, 2019 to September 18, 2019 in adult patients from the same counties. Comparison incidence rates were calculated using 2019 county population data. Results: During the 2020 study period, there were 1,258 total admissions for COVID-19. Of these, 51 patients with VTE were identified from 11 counties: 22 developed DVT and 29 developed PE (total = 51). The average calculated incidence rate of VTE in COVID-19 was 252 per 100,000 population (Graph 1). During the 2019 study period, 526 patients from the same 11 counties were diagnosed with VTE. The average incidence rate of total VTE was 60 per 100,000 population. The incidence rate of VTE in the same population was 4.2 times higher in patients with COVID-19. Conclusions: The incidence of VTE in COVID-19 is approximately 4.2 times higher than incidence rates among the same population without COVID-19 in 2019.