Background: The association between use of renin-angiotensin-aldosterone (RAAS) inhibitors and both SARS-CoV-2 infection and the development of severe COVID-19 has been presented in the recent medical literature with inconsistent results.

Objectives: To assess the association between RAAS inhibitor use and two outcomes: infection with SARS-CoV-2 (Model 1) and severe COVID-19 among those infected (Model 2).

Methods: We accessed used electronic health records of individuals from Israel who were receiving anti-hypertensive medications for this retrospective study. For Model 1 we used a case-control design. For Model 2 we used a cohort design. In both models, inverse probability weighting adjusted for identified confounders as part of doubly robust outcome regression.

Results: We tested 38,554 individuals for SARS-CoV-2 who had hypertension and were being treated with medication; 691 had a positive test result. Among those with a positive test, 119 developed severe illness. There was no association between RAAS inhibitor use and a positive test. Use of RAAS inhibitors was associated with a decreased risk for severe COVID-19 (adjusted odds ratio [OR] 0.47, 95% confidence interval [95%CI] 0.29–0.77) compared with users of non-RAAS anti-hypertensive medication. The association remained significant when use of angiotensin-converting-enzyme inhibitors (adjusted OR 0.46, 95%CI 0.27–0.77) and angiotensin II receptor blockers (adjusted OR 0.39, 95%CI 0.16–0.95) were analyzed separately.

Conclusions: Among individuals with hypertension using RAAS inhibitors, we found a lower risk of severe disease compared to those using non-RAAS anti-hypertensive medications. This finding suggests that RAAS inhibitors may have a protective effect on COVID-19 severity among individuals with medically treated hypertension.