Controversial Relationship between Renin-Angiotensin System Inhibitors and Severity of COVID-19: Announcing a Large Multicentre Case-Control Study in Italy.

Di Castelnuovo, Augusto; De Caterina, Raffaele; de Gaetano, Giovanni; Iacoviello, Licia

The hypothesis has been proposed that patients COVID-19 positive, under anti-hypertensive treatment with angiotensin enzyme inhibitors or angiotensin receptor-blockers, might have a worse or a better clinical prognosis. This might be due to the fact that ACE2 is the receptor for the virus to enter human cells, but, on the contrary, that ACE2 expression is downregulated following SARS-1 infection, resulting in disproportionate activation of renin-angiotensin-aldosterone system and exacerbated pneumonia progression. However, no solid clinical data are available at the present moment to support or disprove such hypotheses. We announce in this letter that a large multicentre case-control study has been started in Italy that is the country with a very high impact of COVID-19 infection. We hope that our letter will encourage other clinical centres, even outside Italy, to join our study.