Effectiveness and Effect on Renal Parameters of Amlodipine vs. Other Dihydropyridine Calcium Channel Blockers in Patients with Essential Hypertension: Retrospective Observational Study Based on Real-World Evidence from Electronic Medical Records.

Introduction: The renoprotective effects of dihydropyridine calcium channel blockers (CCBs) have been established as non-inferior to other classes of antihypertensive drugs. Studying their effect on renal outcome parameters, specifically for amlodipine as monotherapy, in real-world settings can further help in expanding its usage among Indian patients. This study was performed to assess the effects of amlodipine and other dihydropyridine CCBs (cilnidipine, benidipine and azelnidipine) on renal parameters and effectiveness in blood pressure reduction in Indian patients.

Methods: The retrospective data of adult patients (> 18 years) with essential hypertensive who were prescribed amlodipine (n = 92), cilnidipine (n = 91), benidipine (n = 70) or azelnidipine (n = 71) as monotherapy were analyzed. The renal outcomes, serum creatinine, estimated glomerular filtration rate (eGFR), blood urea nitrogen (BUN), microalbumin, urine albumin-to-creatinine ratio (UACR), sodium and potassium levels, and mean changes in BP were analyzed from baseline to 12 months. Appropriate statistical methods were used to determine the significance (p value < 0.05).

Results: From baseline to the end of the study, mean serum creatinine changed from 0.98 ± 0.17 to 1.07 ± 0.28 mg/dL with amlodipine, 0.97 ± 0.18 to 1.13 ± 0.50 mg/dL with cilnidipine, 0.98 ± 0.30 to 0.97 ± 0.27 mg/dL wi th benidipine, and 0.99 ± 0.23 to 0.98 ± 0.25 mg/dL with azelnidipine (p = 0.01). The mean microalbumin and UACR were reduced from baseline to the end of the study (p = 0.06 and p > 0.05). No significant changes were observed in BUN, sodium or potassium levels. Overall, for all CCBs, the mean systolic blood pressure (SBP) and diastolic blood pressure (DBP) values were reduced from baseline to the end of the study (p = 0.002). At the end of the study, the average dose of amlodipine was 7.25 mg, and the average reduction in SBP and DBP per mg dose was 1.54 and 0.57 mmHg. The corresponding numbers for the other CCBs were as follows: cilnidipine, 14.28 mg, 0.26 and 0.01; benidipine, 5.71 mg, 0.41 and 0.11; azelnidipine, 15.88 mg, 0.13 and 0.06.

Conclusion: Amlodipine and other CCBs demonstrated good efficacy and similar effects on renal parameters from baseline to end of study. Amlodipine also showed higher potency by demonstrating greater BP reduction at a lower dose. Thus, amlodipine can remain a preferred choice among CCBs, even with the advent of the newer CCBs.