Deep vein thrombosis in COVID-19 patients in general wards: prevalence and association with clinical and laboratory variables

BACKGROUND: Preliminary reports suggest a hypercoagulable state in COVID-19. Deep vein thrombosis (DVT) is perceived as a frequent finding in hospitalized COVID-19 patients, but data describing the prevalence of DVT are lacking. OBJECTIVES: We aimed to report the prevalence of DVT in COVID-19 patients in general wards, blinded to symptoms/signs of disease, using lower extremities duplex ultrasound (LEDUS) in random patients. We tested the association of DVT with clinical, laboratory and inflammatory markers and also reported on the secondary endpoint of in-hospital mortality. PATIENTS/METHODS: n = 263 COVID-19 patients were screened with LEDUS between March 01, 2020 and April 05, 2020 out of the overall n = 1012 admitted with COVID-19. RESULTS: DVT was detected in n = 67 screened patients (25.5%), n = 41 patients (15.6%) died during the index hospitalization. Multiple logistic regression demonstrated that only C-reactive protein (odds ratio 1.009, 95% CI 1.004–1.013, p < 0.001) was independently associated with the presence of DVT at LEDUS. Both age (odds ratio 1.101, 95% CI 1.054–1.150, p < 0.001) and C-reactive protein (odds ratio 1.012, 95% CI 1.006–1.018, p < 0.001) were instead significantly independently associated with in-hospital mortality. CONCLUSIONS: The main study finding is that DVT prevalence in COVID-19 patients admitted to general wards is 25.5%, suggesting it may be reasonable to screen COVID-19 patients for this potentially severe but treatable complication, and that inflammation, measured with serum C-reactive protein, is the main variable associated with the presence of DVT, where all other clinical or laboratory variables, age or D-dimer included, are instead not independently associated with DVT.