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

Overview

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.

The coronavirus disease 2019 (Covid-19) pandemic is currently the main challenge facing healthcare providers. Data are lacking to guide clinical decision. The renin-angiotensin-aldosterone system (RAAS) is a key process in cardiology. Its inhibition using angiotensin-converting enzyme inhibitors (ACEi) and angiotensin II type 1-receptor blockers (ARBs) is a cornerstone of the long-term management of arterial hypertension, heart failure and acute coronary syndrome. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) uses the angiotensin-converting enzyme 2 (ACE2) as a cellular entry receptor. ACE2 is part of the RAAS and is likely to be modulated by the use of ACEi and ARBs. Therefore, there is concern that patients who are treated with ACEi and ARBs may be at higher risk for Covid-19 infection. However, little is known regarding how ACEi and ARBs could affect Covid-19 infection and severity. First, ACE2 may have a protective effect against lung injury because it degrades angiotensin II to angiotensin-(1-7). Second, the effect of RAAS inhibition on ACE2 expression has been poorly studied in humans. Third, ACE inhibitors and ARB have different effect on the RAAS and therefore their interaction with Covid-19 may differ. The COVHYP study is designed to address part of these issues. This is an analytical retrospective observational study that will collect and analyze data regarding patients hospitalized with suspected Covid-19. We planned to screen for inclusion all consecutive patients referred form 10/03/2020 to 15/04/2020 to the emergency department of the Versailles Hospital, a tertiary center located in greater Paris area - one of the region most affected by Covid-19 in France through this period. The inclusion criteria are as follows: 1) Clinical presentation suggestive of COVID-19 pneumonia, at least fever or influenza-like syndrome AND cough or dyspnea; and 2) Test of the presence of SARS-CoV-2 RNA by RT-PCR in nasopharyngeal or sputum samples. Two groups of patients will be defined, those with confirmed Covid-19 pneumonia, and those without Covid-19. Hospital data will gathered, and patients or relatives will be contacted by phone for a one-month follow-up. We will compare baseline characteristics of patients, especially the previous treatment by ACEi or ARBs, in the two groups of patients, and evaluate whether these characteristics can be associated with diagnosis of SARS-CoV-2 infection and severity. We hope that this study will provide a better understanding of the effect of RAAS inhibitors on Covid-19 pneumonia and its severity.