A research team at Chung-Ang University Hospital said it has discovered that the renin-angiotensin-aldosterone system (RAAS) inhibitors used for hypertension drugs have no relationship to Covid-19 patients’ risk of death in Korea.
The team, led by Professor Kim Won-young, disclosed their finding in a paper published recently with the title of "Association of renin-angiotensin-aldosterone system inhibitors with COVID-19-related outcomes in Korea: a nationwide population-based cohort study."
The researchers compared and analyzed 762 patients who took RAAS inhibitors and 4,417 patients who did not among the 5,179 Korean Covid-19 patients based on data at the Korea Health Insurance Review and Assessment Service.
The average age of patients who received the anti-hypertension drug inhibitors was 62.5 years, 21 years older than patients who did not take medicine. Also, the RAAS inhibitor group included more men, many of whom had comorbidities, such as hypertension, myocardial infarction, heart failure, and cerebrovascular disease.
According to the analysis, after adjusting for patients' age, gender, underlying disease, immunity, and the type of hospital at the time of diagnosis, taking RAAS inhibitors did not affect the mortality rate among Covid-19 patients.
The Covid-19 virus binds to the angiotensin-converting enzyme 2 (ACE2) receptor, a protein on the surface of human cells, and transmits to humans. The presence of ACE2 receptors in the lungs, mainly in epithelial cells, can theoretically raise ACE2 and make it more susceptible to infection when using RAAS inhibitors, a treatment for hypertension and heart failure.
However, medical experts suggested that changing medication for hypertension is unnecessary as there is no evidence that RAAS inhibitors are an independent risk factor in existing clinical studies.
"In-hospital mortality rate was somewhat higher among RAAS inhibitor users than nonusers, but considering the age and comorbidities, we believe that RAAS inhibitor use was not independently associated with a higher risk of mortality among Covid-19 patients," Professor Kim said.
Kim also said that most previous studies were limited because they did not investigate the use of hypertension drugs during hospitalization and evaluate the exposure of drugs before the Covid-19 outbreak.
The study was published on the online edition of Clinical Infectious Diseases of the Infectious Disease Society of America, a science citation index (SCI)-grade journal with an impact factor of 9.055.