Mortality in Patients with COVID-19 on Renin Angiotensin System Inhibitor Long-Term Treatment: An Observational Study Showing that Things Are Not Always as They Seem

INTRODUCTION: At the beginning of the coronavirus disease 2019 (COVID-19) pandemic, controversial data were reported concerning angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) that induced a number of physicians to stop using them in patients with COVID-19. Although large-scale studies have ruled out this concern, it is common experience that patients with COVID-19 taking ACE inhibitors or ARBs are at increased risk of death. The aim of this study was to investigate the reasons for this apparently high mortality rate. METHODS: During the first wave of the pandemic, we conducted a field study of 427 consecutive patients with COVID-19 upon their admission to the emergency department of a hospital in one of the most severely hit cities in northern Italy, and 30 days later. The disease was defined as being mild, moderate or severe on the basis of clinical, laboratory and imaging data, and a multivariate model was used to analyse the determinants of mortality. RESULTS: Within 30 days of admission, 31.6% of the patients treated with ACE inhibitors or ARBs and 15.2% of those not treated with these drugs had died. Multivariate analysis showed that the determinants of mortality were age (p = 0.0001), hypertension (p = 0.0120) and diabetes (p = 0.0129), whereas ACE inhibitors or ARBs had no effect on mortality. There was no significant difference between the patients treated with ACE inhibitors and those treated with ARBs. CONCLUSION: The apparently increased mortality of patients with COVID-19 receiving long-term treatment with ACE inhibitors or ARBs is not due to the drugs themselves, but to the conditions associated with their use.