Coronavirus disease 2019 (COVID-19) is a pandemic infection caused by a virus called severe
acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Because SARS-CoV-2 is known to require
the angiotensin-converting enzyme 2 (ACE-2) receptor for uptake into the human body, there
have been questions about whether medications that upregulate ACE-2 receptors might increase
the risk of infection and subsequent complications. One such group of medications are
anti-hypertensives that block the renin-angiotensin system, including both angiotensin
converting enzyme inhibitors (ACEi) and angiotensin II receptor blockers (ARB). Both ACEi and
ARB are widely used for the treatment of hypertension. Early reports from China and Italy
suggest that many of those who die from COVID-19 have a coexisting history of hypertension.
Consequently, there have been questions raised as to whether these 2 types of blood pressure
medication might increase the risk of death among patients with COVID-19. However, it is well
known that the prevalence of hypertension increases linearly with age. Therefore, it is
possible that the high prevalence of hypertension and ACEi/ARB use among persons who die from
COVID-19 is simply confounded by age (older people are at risk of both a history of
hypertension and dying from COVID-19). Whether these commonly prescribed blood pressure
medications increase the risk of COVID-19 or not remains unanswered. Statements from
professional cardiology societies on both sides of the Atlantic have called for urgent
research into this question. Our study aims to randomize patients with primary (essential)
hypertension who are already taking ACEi/ARB to either switch to an alternative BP medication
or continue with the ACEi/ARB that they have already been prescribed. Adults with compelling
indications for ACEi/ARB will not be enrolled.