Endocrine Abstracts

Introduction: The year 2020 has witnessed a new global pandemic caused by an encased single-stranded RNA virus identified as the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The exceptionally infectious capability of the virus, along with case fatality rate ranging from 0.99% to above 3%, have raised major global concerns.

COVID19 and Risk factors

Evidence from several observational studies suggests risk factors for poor COVID-19 patients’ outcome. Among these, both Diabetes and hypertension are associated with increased risk. hypertension was the most frequent comorbidity with an estimated prevalence of 15% – 30%.

The renin-angiotensin-aldosterone system (RAAS)

The renin-angiotensin-aldosterone system plays an important role in controlling blood pressure. Angiotensin-converting enzyme (ACE) inhibitors or blockers (ARBs) are highly recommended for the management of patients with cardiovascular diseases. They are also widely used to slow the progress of renal insufficiency in Diabetic patients. These medications together with NSAIDs and Thiazolidinediones can cause upregulation of ACE2 (Angiotensin-converting enzyme 2). Evidence showed increased cardiac ACE2 activity with ACEi/ARBs and increased urinary ACE2 with Olmesartan. ACE2 has been recognized as SARS-CoV-2 binding site to cells. It is not clear if this upregulation of ACE2 is beneficial or harmful. It has been argued that this upregulation could lead to increased patient susceptibility to viral dissemination. Conversely, there is a suggestion that ARB treatment helped reversing the lung injury due to reduction in ACE2 caused by SARS-CoV (the cause of the 2003 pandemic) in mice. A preliminary trial of ACE2 administration to individuals with acute respiratory distress syndrome demonstrated no improvement in lung function. This is a review of the most recent relevant literature on the matter examining several recent observational studies that examined the relationship between ACEI/ARB and COVID19. The reviewed 8 observational studies (with risks of confounding factors) reached the conclusion that there is no sufficient data to advocate stopping ACE/ARB treatment in patients with COVID-19. There were some contradictory findings regarding possible different effects of the two drug classes.

Conclusion: The strong beneficial effects of ACEI/ARB for some patients currently outweigh the theoretical risks. This review supports the British cardiovascular society recent statement that ‘Patients should continue treatment with ACEi and ARBs unless advised to stop by their medical team’. This also echoes the American Heart association view on the subject.