A population-based case-control study in Lombardy, Italy, investigated the association between the use of renin-angiotensin-aldosterone system (RAAS) blockers (ACE inhibitors and ARBs) and the risk of coronavirus disease 2019 (Covid-19). The study included 6272 case patients confirmed with SARS-CoV-2 infection and 30,759 controls. The mean age of both groups was 68 ± 13 years, with 37% being women. The use of ACE inhibitors and ARBs was more common among case patients than controls, as was the use of other antihypertensive and non-antihypertensive drugs. However, no significant association was found between the use of ARBs or ACE inhibitors and the risk of Covid-19, either in the general population or among patients with severe or fatal disease. The study also found no association between these drugs and the severity of the disease according to sex. The study concluded that while the use of ACE inhibitors and ARBs was more frequent among patients with Covid-19 due to their higher prevalence of cardiovascular disease, there was no evidence that these drugs affected the risk of Covid-19. The findings suggest that RAAS blockers do not independently increase or decrease the risk of Covid-19. The study also found that other antihypertensive drugs, such as calcium-channel blockers, beta-blockers, and diuretics, were more commonly used among patients with Covid-19, but these drugs were not significantly associated with the risk of infection. The study highlights the importance of considering the clinical profiles of patients when evaluating the impact of antihypertensive drugs on the risk of Covid-19. The results indicate that the use of RAAS blockers is not independently associated with the susceptibility to or severity of Covid-19 in humans.A population-based case-control study in Lombardy, Italy, investigated the association between the use of renin-angiotensin-aldosterone system (RAAS) blockers (ACE inhibitors and ARBs) and the risk of coronavirus disease 2019 (Covid-19). The study included 6272 case patients confirmed with SARS-CoV-2 infection and 30,759 controls. The mean age of both groups was 68 ± 13 years, with 37% being women. The use of ACE inhibitors and ARBs was more common among case patients than controls, as was the use of other antihypertensive and non-antihypertensive drugs. However, no significant association was found between the use of ARBs or ACE inhibitors and the risk of Covid-19, either in the general population or among patients with severe or fatal disease. The study also found no association between these drugs and the severity of the disease according to sex. The study concluded that while the use of ACE inhibitors and ARBs was more frequent among patients with Covid-19 due to their higher prevalence of cardiovascular disease, there was no evidence that these drugs affected the risk of Covid-19. The findings suggest that RAAS blockers do not independently increase or decrease the risk of Covid-19. The study also found that other antihypertensive drugs, such as calcium-channel blockers, beta-blockers, and diuretics, were more commonly used among patients with Covid-19, but these drugs were not significantly associated with the risk of infection. The study highlights the importance of considering the clinical profiles of patients when evaluating the impact of antihypertensive drugs on the risk of Covid-19. The results indicate that the use of RAAS blockers is not independently associated with the susceptibility to or severity of Covid-19 in humans.