Patients with severe COVID-19 have reduced circulating levels of angiotensin-(1–7): A cohort study

Abstract

Background and Aims: Angiotensin-converting enzyme 2 (ACE2) acts as a functional receptor for the entry of severe acute respiratory syndrome coronavirus 2 into host cells. Angiotensin (1–7) (Ang (1–7)) obtained from the function of ACE2 improves heart and lung function. We investigated the relationship between Ang (1–7) level and disease severity in patients with coronavirus disease 2019 (COVID-19). Methods: This cohort study was carried out at Masih Daneshvari Hospital in Tehran, Iran from September 2020 to October 2020. To do so, the Ang (1–7) levels of 331 hospitalized COVID-19 patients with and without underlying disease were measured by ELISA kit. The need for oxygen, intubation, and mechanical ventilation were recorded for all the patients. Results: Results showed a significant inverse relationship between the levels of Ang 1–7 and the severity of the disease (needed oxygen, intubation, and mechanical ventilation). According to the results, median (interquartile range) of Ang (1–7) levels was significantly lower in patients who needed oxygen versus those who needed no oxygen (44.50 (91) vs. 82.25 (68), p = 0.002), patients who needed intubation and mechanical ventilation versus those who did not (9.80 (62) vs. 68.70 (102), p < 0.000) and patients hospitalized in an intensive care unit (ICU) than people hospitalized in other wards. We also found that the older patients were more in need of ICU and mechanical ventilation than younger patients. Conclusions: Higher levels of Ang (1–7) have been associated with decreased disease severity. Besides this, we perceived that synthetic Ang 1–7 peptides may be useful to treat and reduce the complications of COVID-19.