ACE and lymphopenia: ACE inhibitors (ACEIs) and angiotensin II receptor blockers (ARBs) decrease the level of ACE and increase the level of ACE2 [14], which may increase the risk of SARS-CoV-2 infection, which may be the reason why more patients with hypertension and coronary heart disease also had lymphopenia, as ACEIs and ARBs are commonly used drugs under these circumstances.