Haemodynamic comparison of amlodipine and atenolol in essential hypertension using the quantascope

Effect of amlodipine on systolic blood pressure

BACKGROUND

Systolic hypertension is the most common form of hypertension, particularly in people aged >60 years. Caused by decreased compliance of large arteries, systolic hypertension is an independent risk factor for cardiovascular disease. Recent studies have demonstrated that it is more important to control systolic blood pressure (SBP) than diastolic blood pressure (DBP).

OBJECTIVE

The objective of this study was to perform a systematic literature review to examine the effectiveness of amlodipine in lowering SBP in a variety of patient subgroups and clinical settings.

METHODS

The literature review methodology included identifying, selecting, appraising, extracting, and synthesizing primary research studies. Following an a priori protocol, published literature was searched from 1980 to 2001 using 3 electronic databases. A manual review of the reference lists of recent review articles and all accepted studies was performed. Parallel-group, randomized, controlled trials that included at least 10 adults with baseline hypertension (SBP>or=140 mm Hg, DBP>or=90 mm Hg, or both), included at least 1 arm randomized to initial treatment with amlodipine monotherapy, had a minimum treatment duration of 8 weeks, and reported baseline and end-point blood pressure were included.

RESULTS

Of 696 citations identified, 85 primary studies met all inclusion criteria. Comparable treatment arms were pooled, and weightd mean SBP was calculated. In the amlodipine monotherapy arms, which included >5000 patients, SBP decreased by a mean of 17.5 mm Hg from baseline. The effect of amlodipine in reducing SBP was greater in elderly patients (age>or=60 years) and patients with author-defined isolated systolic hypertension. The dose was titrated to achieve the target blood pressure in 73 of 89 amlodipine treatment arms, whereas 16 treatment arms reported fixed doses. The median daily dose was 5 mg (range, 1.25-15 mg) in both the fixed-dose and dose-titration groups.

CONCLUSIONS

In this review of the published literature, amlodipine monotherapy was effective in reducing SBP. Antihypertensive agents such as amlodipine warrant consideration for the management of patients with inadequately controlled SBP.

Amlodipine. A reappraisal of its pharmacological properties and therapeutic use in cardiovascular disease

Amlodipine belongs to the dihydropyridine class of calcium channel blockers. Both short and long term studies indicate that amlodipine effectively lowers mild to moderately elevated blood pressure and relieves symptoms of angina pectoris. In comparative studies, its antihypertensive efficacy is similar to that of other established agents such as beta-blockers, diuretics, ACE inhibitors and other calcium channel blockers (including the dihydropyridines); limited comparative data are, however, available in patients with angina pectoris. Amlodipine may offer potential in patients with congestive heart failure. Vasodilator adverse events such as oedema, headaches, and flushing are commonly observed with amlodipine. The drug does not appear to cause postural hypotension, reflex tachycardia or cardiac conduction disturbances. Comparative studies suggest that amlodipine is at least as well tolerated as other standard agents. Thus, amlodipine provides an attractive therapeutic option for the treatment of hypertension, and offers potential for patients with angina pectoris. Its beneficial effects in patients with congestive heart failure require confirmation in future studies.