Before revision:  Federated across two ARD cohorts, our main result shows that patients using \alpha_1-AR antagonists, as compared to nonusers , had a 40 \% relative risk reduction for ventilation and dying ( p= 0.014 ).
After revision:  Federated across two ARD cohorts, our main result shows that patients using \alpha_1-AR antagonists, as compared to unexposed patients , had a 40 \% relative risk reduction for ventilation and dying ( p= 0.014 ).