Atrial fibrillation and the risk of 30-day incident thromboembolic events, and mortality in adults ≥ 50 years with COVID-19

Background: There are limited data on the outcomes of adults with coronavirus disease 2019 (COVID-19) and atrial fibrillation (AF). The objectives were to (i) examine associations between AF, 30-day thromboembolic events and mortality in adults with COVID-19 and (ii) examine associations between COVID-19, 30-day thromboembolic events and mortality in adults with AF. Methods: A study was conducted using a global federated health research network. Adults aged ≥50 years who presented to 41 participating healthcare organizations between 20 January 2020 and 1 September 2020 with COVID-19 were included. Results: For the first objective, 6589 adults with COVID-19 and AF were propensity score matched for age, gender, race, and comorbidities to 6589 adults with COVID-19 without AF. The survival probability was significantly lower in adults with COVID-19 and AF compared to matched adults without AF (82.7% compared to 88.3%, Log-Rank test P <.0001; Risk Ratio (95% confidence interval) 1.61 (1.46, 1.78)) and risk of thromboembolic events was higher in patients with AF (9.9% vs 7.0%, Log-Rank test P <.0001; Risk Ratio (95% confidence interval) 1.41 (1.26, 1.59)). For the second objective, 2454 adults with AF and COVID-19 were propensity score matched to 2454 adults with AF without COVID-19. The survival probability was significantly lower for adults with AF and COVID-19 compared to adults with AF without COVID-19, but there was no significant difference in risk of thromboembolic events. Conclusions: AF could be an important risk factor for short-term mortality with COVID-19, and COVID-19 may increase risk of short-term mortality amongst adults with AF.