In summary, by analyzing data from 903 cardiology patients who had various degrees of renal dysfunction, we found that FGF23 levels were associated positively and negatively with, respectively, LVH and low LVEF independent of age, sex, eGFR, corrected calcium, CRP, diuretic use, systolic blood pressure, and history of hypertension not only among patients with CKD (CKD stage G3a/G3b/G4) but also those without (CKD stage G1/G2). Here, CRP is linked to chronic kidney disease.