ACE and acute kidney injury: On the other hand, cluster 2 was mainly characterized by younger age, lower comorbidity burden, especially less history of hypertension, diabetes mellitus, coronary artery disease, and leukemia/lymphoma, less use of angiotensin converting enzyme inhibitors (ACEI)/angiotensin receptor blockers (ARB), and diuretics, less acute kidney injury (AKI), higher eGFR, and lower serum albumin and calcium.