ACE and heart failure: In models that included other risk factors for CA-AKI, including hypertension, diabetes, prior heart failure, contrast volume, eGFR, log CRP, and medications (angiotensin-converting enzyme inhibitors/angiotensin receptor blockers and loop diuretics), the highest versus lowest tertile of FGF-23 was associated with a 6.82-fold greater risk for CA-AKI (95% CI, 2.22–21.01), and a 90% higher risk per doubling of FGF-23 levels.