Renin-Angiotensin-Aldosterone System Inhibitors, Hypertension, and COVID-19

Background. Angiotensing converting enzyme type 2 (ACE2), a key enzyme of the renin-angiotensin-aldosterone system (RAAS), is the receptor of SARS-CoV-2 for cell entry into lungs. Because ACE2 may be modulated by RAAS inhibitors, such as angiotensin converting enzyme inhibitors (ACEi) and angiotensin II receptor blockers (ARBs), there is concern that patients treated with ACEi and ARBs may be at higher risk for COVID-19 infection and severity. Aim. To analyze the associations between COVID-19 and hypertension, and treatments with ACEi and ARBs. Methods. In this retrospective observational study, consecutive patients hospitalized for suspected COVID-19 pneumonia will be divided into 2 groups, whether or not COVID-19 is confirmed. The two groups will be compared for baseline characteristics, mainly prior treatment with ACEi and ARBs, and clinical outcome at 1-month follow-up. The main hypothesis is that ACEi and ARBs, which interact differently with ACE2, may have different relationships with COVID-19 infection or severity.