Risk of venous thromboembolism in patients with COVID-19 during 2020; a retrospective cross-sectional study in a Swedish health care system.

To establish the impact of COVID-19 on the pre-test probability for VTE in patients with suspected VTE. This was a retrospective, observational, cross-sectional study of patients 18 years and older undergoing diagnostic tests for VTE in an integrated healthcare system covering a population of 465,000 during the calendar year of 2020. We adjusted for risk factors such as age, sex, previous VTE, ongoing anticoagulant treatment, malignancy, Charlson score, ward care, ICU care and wave of COVID-19. In total, 303 of 5041 patients had a positive diagnosis of COVID-19 around the time of investigation. The prevalence of VTE in COVID-positive patients was 10.2% (36/354), 14.7% (473/3219) in COVID-19 negative patients, and 15.6% (399/2589) in patients without a COVID-19 test. A COVID-positive status was not associated with an increased risk for VTE (crude odds ratio 0.64, 95% CI 0.45-0.91, adjusted odds ratio 0.46, 95%CI 0.19-1.16). We found no increased VTE risk in COVID-positive patients. This indicates that COVID-19 status should not influence VTE workup.The study was pre-registered on May 26, 2020 at ClinicalTrials.gov with identifier NCT04400877.

Evidence of overtesting for venous thromboembolism in patients with COVID-19 – results of a retrospective observational multicenter study from Sweden

ObjectivesEpidemiological data and studies on hospitalized patients from the beginning of the SARS-CoV-2 pandemic have shown an increased prevalence of Venous Thromboembolism (VTE) in patients with COVID19 and several guidelines advocate a higher vigilance for VTE in outpatients with COVID19. However, studies have found no increased risk of VTE when adjusting for other risk factors. As COVID19 becomes endemic, its impact on the pre-test probability for VTE needs to be established to prevent unwarranted workups for VTE in patients with COVID19. In this study we wanted to investigate the predictive value of COVID19 in patients with suspected VTE during 2020 in a whole Swedish county (Östergötland) with 465000 inhabitants.MethodsThis was a retrospective observational cross-sectional study of patients within an integrated healthcare system in Sweden, covering a population of 465 000. Patients 18 years and older with a diagnostic test for VTE between 1 of January and 31 of December 2020 were included. Testing for VTE was performed with ultrasound for deep venous thrombosis (DVT) and with pulmonary angiography for pulmonary embolism (PE). COVID19 positive status was defined as a positive PCR test for SARS-CoV-2 within 14 days prior, to 7 days after testing for VTE. Risk for VTE with COVID19 was assessed by logistic regression, adjusting for risk factors such as age, sex, previous VTE, ongoing anticoagulant treatment, malignancy, Charlson score, ward care, and ICU care.ResultsDuring 2020, 6523 patients were investigated for possible VTE of which 354 had a positive diagnosis of COVID19 around the time of investigation. The prevalence of VTE in COVID19 positive patients was 10.2% (36/354) compared to 14.7% (473/3219) in COVID19 negative patients and 15.6% (399/2589) in patients without a COVID19 test. The prevalences of PE were 10.7% (32/299), 15.6% (308/1969) and 17.4% (158/906) and the prevalences of DVT was 8.6% (5/58), 13.1% (168/1281) and 14.4% (246/1713), for COVID19 positive, negative and untested patients respectively. A COVID-positive test was not associated with an increased risk for VTE (crude odds ratio 0.64, 95%CI 0.45 - 0.91, adjusted odds ratio 0.46, 95%CI 0.19 - 1.16).ConclusionsWe found no increased risk of VTE in COVID19 positive patients, suggesting that COVID19 status should not influence VTE workup. In the logistic regression analysis the odds for a VTE was lower for patients with COVID19. This is likely an indication of overtesting in this group of patients and stresses the importance of accurate pre-test assessment when considering a VTE workup in patients with COVID19 infection.

Risk of venous thromboembolism in a Swedish healthcare system during the COVID-19 pandemic: A retrospective cross-sectional study.

OBJECTIVE: The objective of this study was to investigate the risk and prevalence of venous thromboembolism (VTE) for patients undergoing a diagnostic test for VTE with confirmed COVID-19 infection compared with patients with no COVID-19 infection. METHODS: This was a retrospective cross-sectional study of patients in an integrated healthcare system in Sweden, covering a population of 465,000, with a diagnostic test for VTE between March 1 and May 31 in the years 2015 to 2020. Risk for VTE with COVID-19 was assessed by logistic regression, adjusting for baseline risk factors. RESULTS: A total of 8702 patients were included, and 88 of those patients tested positive on the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) polymerase chain reaction test. A positive SARS-CoV-2 test did not increase the odds for VTE (odds ratio, 0.97; 95% confidence interval [CI], 0.55-1.74) and did not change when adjusting for sex, previous VTE, previous malignancy, Charlson score, hospital admission, intensive care, or ongoing treatment with anticoagulation (odds ratio, 0.72; 95% CI, 0.16-3.3). The prevalence of VTE was unchanged in 2020 compared with 2015 to 2019 (16.5% vs 16.1%, respectively), and there was no difference in VTE between the SARS-CoV-2 positive, negative, or untested groups in 2020 (15.9%, 17.6%, and 15.7%, respectively; P = 0.85). CONCLUSIONS: We found no increased prevalence of VTE in the general population compared with previous years and no increased risk of VTE in patients who were SARS-CoV-2 positive, suggesting that SARS-CoV-2 status should not influence VTE workup in the emergency department. The prevalence of VTE was high in patients with SARS-CoV-2 treated in the intensive care unit (ICU), where the suspicion for VTE should remain high.