Remote history of VTE is associated with severe COVID-19 in middle and older age: UK Biobank cohort study.

Background: Venous thromboembolism (VTE) is a common, life-threatening complication of COVID-19 infection. COVID-19 risk-prediction models include a history of venous thromboembolism. However, it is unclear whether remote history (>9 years previously) of VTE also confers increased risk of COVID-19. Objectives: To investigate possible association between VTE and COVID-19 severity, independent of other risk factors. Methods: Cohort study of UK Biobank participants recruited between 2006-2010. Baseline data, including history of VTE, were linked to COVID-19 test results, COVID-19 related hospital admissions and COVID-19 deaths. The risk of COVID-19 hospitalisation or death was compared for participants with a remote history VTE versus without. Poisson regression models were run univariately then adjusted stepwise for socio-demographic, lifestyle and comorbid covariates. Results: After adjustment for socio-demographic and lifestyle confounders and comorbid conditions, remote history of VTE was associated with non-fatal community (RR 1.61, 95% CI 1.02-2.54, p=0.039), non-fatal hospitalised (RR 1.52, 95% CI 1.06-2.17, p=0.024) and severe (hospitalised or fatal) (RR 1.40, 95% CI 1.04-1.89, p=0.025) COVID-19. Associations with remote history of VTE were stronger among men (severe COVID-19: RR 1.68, 95% CI 1.14-2.42, p=0.009) than for women (severe COVID-19: RR 1.07, 95% CI 0.66-1.74, p=0.786). Conclusion: Our findings support inclusion of remote history of VTE in COVID-19 risk-prediction scores, and consideration of sex-specific risk scores.