Amlodipine blood pressure regulation, Hypertension management with Amlodipine, Blood Pressure
Hypertension stands as the leading factor contributing to the increasing rates of mortality and disability linked to cardiovascular diseases.[1] With almost 220 million people living with elevated blood pressure, hypertension poses a substantial health challenge in India.[2]
A recent national survey reported that almost one out of every three individuals have hypertension with only one-fifth of them being successful in managing it.[3]
Major guidelines recommend calcium channel blockers, either as monotherapy or in combination with other antihypertensives, for the management of hypertension. Amlodipine stands as the most preferred choice among calcium channel blockers, with approximately 76% of Indian physicians favoring it, according to a study.[4] It is widely considered the benchmark in the management of hypertension by most physicians.[5]
The primary factor preventing the attainment of treatment objectives in antihypertensive therapy is the patient's adherence to the prescribed dosing regimen.5 Because of its high oral bioavailability ranging from 60% to 80% and a long half-life of 35–50 hours, amlodipine is prescribed once daily, which is beneficial in ensuring patient adherence.[6],[7] It induces a gradual and sustained decrease in blood pressure owing to its extended elimination half-life and slow receptor dissociation kinetics.3 Blood pressure regulation remains effective even in instances where a dose has been inadvertently skipped, which represents the most prevalent form of non-adherence in hypertension management.[7]
Inadequate blood pressure control has been associated with complications, such as stroke, myocardial infarction, and renal failure. Maintaining persistent and effective control of blood pressure is crucial in preventing these complications. A single daily dose of amlodipine has been documented to sustain blood pressure control consistently over 24 hours, exhibiting minimal fluctuations.7 Numerous studies have emphasized the persistent qualitative and quantitative impact of amlodipine in maintaining effective 24-hour blood pressure regulation, which is a key factor for reducing the cardiovascular risk associated with it.[8]
As per a randomized trial published in the American Journal of Cardiology, a 5 mg daily dose of amlodipine was found to be well-tolerated and proved to be efficient in keeping both systolic and diastolic blood pressure below the baseline values at each hour during the 24-hour monitoring period.3,[9]Another multicenter, multinational, randomized, double-blind, placebo-controlled study conducted by Zhang et al. assessing the 24-hour ambulatory blood pressure of 577 patients reported that amlodipine demonstrated effectiveness and tolerability consistently across all time intervals, even when accounting for the overall reduction in mean blood pressure.3,[10]A pooled analysis of five different studies found that the blood pressure variability was markedly and significantly lower (p<0.0001) when using amlodipine compared to atenolol, lisinopril, and enalapril.3 In a multicenter, randomized trial investigating the efficacy of amlodipine and the gastrointestinal therapeutic system formulation of nifedipine, amlodipine demonstrated greater effectiveness in lowering the 24-hour blood pressure, with a reduction of 2–3 mmHg.3,[11]
The smoothness index (SI) offers a more advanced measure for gauging the effectiveness of the antihypertensive treatment throughout the 24-hour dosing cycle. A higher SI value typically signifies a steady and favorable reduction in blood pressure with minimal variability. Consequently, it indicates enhanced cardiovascular protection and improved prevention from damage to the target organ. Numerous studies have assessed the effectiveness of amlodipine on 24-hour blood pressure monitoring using SI as a metric.[3]
A meta-analysis of 11 randomized trials involving 5188 individuals with hypertension, which examined the therapeutic efficacy of losartan, valsartan, telmisartan, ramipril, and amlodipine, revealed that amlodipine at a dosage of 5 mg exhibited superior SI compared to all other antihypertensives. Evidence suggests that amlodipine maintains a steady reduction in blood pressure over the course of 24 hours due to its high trough-to–peak ratio of 0.85 and a robust SI.[3]
In summary, an ideal treatment for hypertension should encompass a multifaceted strategy. It should possess a long half-life, regulate blood pressure persistently throughout the 24-hour dosing interval, diminish blood pressure variability, and have a high SI.[3] Amlodipine stands true to all these parameters, making it an ideal choice for 24-hour blood pressure regulation, either alone or in combination with other antihypertensives.
References
[1] Lee J, Wilkens J, Meijer E, et al. Hypertension awareness, treatment, and control and their association with healthcare access in the middle-aged and older Indian population: A nationwide cohort study. PLoS Med. 2022;19(1):e1003855.
[2] India Hypertension Control Initiative, a high impact and low-cost solution. Available at: https://www.who.int/india/news/detail/02-06-2022-india-hypertension-control-initiative--a-high-impact-and-low-cost-solution. Accessed on: 30 August 2023.
[3] Nair T, Sreenivas Kumar A, Unni TG, et al. 24-hour blood pressure control with amlodipine: A review of the current scenario. J Card Crit Care. 2022;6:59–68.
[4] Khan MY, Pandit S, Ray S, et al. Effectiveness of amlodipine on blood pressure control in hypertensive patients in India: A real-world, retrospective study from electronic medical records. Drugs Real World Outcomes. 2020;7(4):281–293.
[5] Neutel JM, Smith DH. Evaluation of angiotensin II receptor blockers for 24‐hour blood pressure control: Meta‐analysis of a clinical database. J Clin Hypert. 2003;5(1):58–63.
[6] DP, Guha S, Rathod R, et al. Effectiveness of amlodipine in the control of 24-hour blood pressure in mild-to-moderate essential hypertension: A Prospective, multicenter, observational real-world study from India. Cureus. 2023;15(4):e38272.
[7] Wang J, Palmer B, Anderson KV, et al. Amlodipine in the current management of hypertension. J Clin Hypertens. 2023;25(9):801–807.
[8] Dorairaj P, Guha S, Sharma S, et al. PS-C10-9: Effectiveness of amlodipine on 24-hour ambulatory blood pressure in adult patients with mild-moderate essential hypertension: A multicentre observational, real-world study. J Hypertension. 2023;41(Suppl 1):e213–e214.
[9] Burris JF, Allenby KS, Mroczek WJ. The effect of amlodipine on ambulatory blood pressure in hypertensive patients. AmJ Cardiol. 1994;73(03):39A–43A.
[10] Zhang Y, Agnoletti D, Safar ME, et al. Effect of antihypertensive agents on blood pressure variability: The Natrilix SR versus candesartan and amlodipine in the reduction of systolic blood pressure in hypertensive patients (X-CELLENT) study. Hypertension. 2011;58(2):155–160.
[11] Huang QF, Sheng CS, Li Y, et al. A randomized controlled trial on the blood pressure-lowering effect of amlodipine and nifedipine-GITS in sustained hypertension. J Clin Hypertens (Greenwich). 2019;21(5):648–657.
