Before revision:   These results highlight the urgent need for prospective trials testing whether prophylactic \alpha-blockers improve outcomes in diseases with a prominent hyperinflammatory component such as COVID-19.
After revision:  We replicated these methods on three pneumonia cohorts, all with similar effects on both outcomes. All results were robust to various sensitivity analyses. These results highlight the urgent need for prospective trials testing whether prophylactic \alpha-blockers improve outcomes in diseases with a prominent hyperinflammatory component such as COVID-19.