EDN1 and Hyperinsulinemia: Based on the results of univariate analysis, multivariate regression analysis was performed and showed that six variables were significantly associated with amlodipine responsiveness, including hyperinsulinemia, IR, serum creatinine concentrations, eGFR, ET-1_b (calculated as 4 × plasma ET-1/SD [standard deviation]) and amlodipine dosages.