ACE inhibitors, beta-blockers, calcium blockers, and diuretics for the control of systolic hypertension

The objective of this study was to determine which of the common groups of antihypertensive drugs is most effective at lowering systolic blood pressure (SBP) in elderly patients with previously untreated hypertension and the percentage of patients controlled with single or sequential monotherapy. Subjects were recruited from patients attending other outpatient clinics and entered into the study if their SBP was more than 150 mm Hg after three visits. Patients were given a low and high dose of each of the main classes of drugs or placebo for 1 month each. The study was a balanced, randomized crossover design with five periods: placebo; angiotensin converting enzyme inhibitors; beta-blocking drugs; calcium-blocking drugs; and thiazide diuretics. Blood pressure (BP) was measured 24 to 26 h after the previous dose. A questionnaire for side effects was administered at each visit. Seventy-four patients entered the study. beta-Blockers could not be used in 15 patients because of asthma or bronchospasm and these had two placebo periods. There were 9 of 66 patients on P, 9 of 46 on beta-blockers, 4 of 65 on calcium-blocking drugs, 4 of 65 on diuretic, and 1 of 62 patients on ACE inhibitors who did not progress to the higher dose because of side effects. Decreases in SBP compared to randomized placebo were calcium-blocking drugs 15 mm Hg = diuretic 13 mm Hg > ACE inhibitors 8 mm Hg = beta-blockers 5 mm Hg. Blood pressure decrease correlated with placebo BP (P < .0005, r = 0.53 to 0.70). When corrected for placebo, target SBP (<140 mm Hg) was reached in between 6% to 15% of patients on monotherapy. Sequential monotherapy achieved target in 29%. Angiotensin converting enzyme inhibitors, calcium-blocking drugs, and diuretics had no more side effects than placebo. Patients on beta-blockers had more side effects and the well-being score was reduced. Diuretics and calcium-blocking drugs are more effective in elderly patients at lowering SBP pressure. beta-Blockers were relatively ineffective, were frequently contraindicated, and had more side effects. Monotherapy achieved control in only a small number of patients. In elderly people with essential hypertension, therapy should be instituted with diuretics or calcium-blocking drugs, but combination therapy will usually be required to achieve goal.     

Sudden death: ACE inhibitors and beta-blockers

Sudden death is extremely common in patients suffering from cardiovascular diseases. At least one third of those with hypertension and probably about half of those who survive a myocardial infarction or suffer from cardiac failure who die in a clinical trial, die suddenly. Beta-blockers reduce the risk of sudden death in patients with cardiovascular disease, particularly in those who have had a myocardial infarction or heart failure. ACE inhibitors are perhaps less effective. Other cardiovascular drugs have not been shown to reduce the risk of sudden death.     

ACE inhibitors versus diuretics: When to choose which drug?

Summary ACE inhibitors and diuretics should be used in combination in the majority of patients with clinical congestive heart failure. The broad spectrum of heart failure should include the phase of significant left ventricular dysfunction without overt clinical heart failure for which ACE inhibitor treatment alone may be beneficial in selected cases.     

Beneficial action of candesartan cilexetil plus amlodipine or ACE inhibitors in chronic nondiabetic renal disease

Although multiple antihypertensive agents are required to control blood pressure (BP) in chronic renal disease, it remains undetermined whether the combination therapy with angiotensin receptor blockers (ARB) plus calcium antagonists or angiotensin-converting enzyme inhibitors (ACEI) confers more preferable action on renal disease than the ARB monotherapy. In the present study, we compared the effect of the combination therapy with ARB plus calcium antagonists/ACEI on proteinuria with that of the ARB monotherapy in chronic nondiabetic renal disease. At 1 month of the drug treatment, the candesartan monotherapy (n=19) reduced BP from 154+/-3/93+/-2 to 146+/-3/88+/-2 mmHg (P<0.05), and a similar magnitude of BP reductions was observed with the combination therapy with candesartan plus ACEI/amlodipine (from 153+/-2/95+/-2 to 144+/-2/88+/-2 mmHg, P<0.05, n=39). The depressor action of these therapies was sustained throughout the 12-month treatment. In contrast, the reduction in proteinuria was greater with the combination therapy (-52+/-3% at 12 months, n=39) than with the candesartan monotherapy (-25+/-3%, n=19), although the baseline values of proteinuria were nearly the same in the candesartan monotherapy group (1.74+/-0.22 g/day) and the combination therapy group (2.10+/-0.19 g/day, P>0.2). Of note, the proteinuria-sparing effect did not differ between the candesartan+ACEI group and the candesartan+amlodipine group. In conclusion, the present study suggests more beneficial action of the combination therapy with ARB plus ACEI/amlodipine than the ARB monotherapy in nondiabetic renal disease. Since the reduction in BP was achieved to the same level, the distinct proteinuria-sparing action of these therapies is attributed to BP-independent mechanisms, which should vary depending on the agents used.     

Effect of ACE inhibitors and beta-blockers on homocysteine levels in essential hypertension

Recent studies have shown that antihypertensive drugs like diuretics increase plasma homocysteine (Hcy) levels. However, the effect of other antihypertensive drugs on plasma Hcy levels has not been tested extensively. The aim of present study was to investigate the effect of antihypertensive therapy (AHT) on Hcy levels in essential hypertensive subjects. A case-control study of 273 patients with essential hypertension (EH) and 103 normotensive controls was undertaken. Plasma Hcy levels were measured before and after 6 weeks of AHT. The genotyping of MTHFR C677T polymorphism was performed by polymerase chain reaction-restriction fragment length polymorphism. Angiotensin-converting enzyme (ACE) inhibitors and beta-blockers significantly decreased and hydrochlorothiazides significantly increased the plasma Hcy levels in hypertensive patients (P<0.05). No significant association between MTHFR C677T genotypes and changes in Hcy levels in response to antihypertensive was observed in EH patients. The decrease in Hcy induced by beta-blockers and ACE inhibitors observed in our study may be due to the improvement of endothelial function along with improved renal function. Thus, our results suggest that ACE inhibitors and beta-blockers may provide additional beneficial therapeutic effects to the EH patients by decreasing Hcy levels.     

Practical recommendations for the use of ACE inhibitors, beta-blockers, aldosterone antagonists and angiotensin receptor blockers in heart failure: putting guidelines into practice

Surveys of prescribing patterns in both hospitals and primary care have usually shown delays in translating the evidence from clinical trials of pharmacological agents into clinical practice, thereby denying patients with heart failure (HF) the benefits of drug treatments proven to improve well-being and prolong life. This may be due to unfamiliarity with the evidence-base for these therapies, the clinical guidelines recommending the use of these treatments or both, as well as concerns regarding adverse events. ACE inhibitors have long been the cornerstone of therapy for systolic HF irrespective of aetiology. Recent trials have now shown that treatment with beta-blockers, aldosterone antagonists and angiotensin receptor blockers also leads to substantial improvements in outcome. In order to accelerate the safe uptake of these treatments and to ensure that all eligible patients receive the most appropriate medications, a clear and concise set of clinical recommendations has been prepared by a group of clinicians with practical expertise in the management of HF. The objective of these recommendations is to provide practical guidance for non-specialists, in order to increase the use of evidenced based therapy for HF. These practical recommendations are meant to serve as a supplement to, rather than replacement of, existing HF guidelines.     

Individual responses to converting enzyme inhibitors and calcium antagonists

This study was designed to assess whether the acute blood pressure response of an individual hypertensive patient to a calcium antagonist or an angiotensin converting enzyme (ACE) inhibitor is a good predictor of the long-term efficacy of these drug classes in this particular patient. The concept that good responses to ACE inhibitors and calcium antagonists may be mutually exclusive was also tested. Sixteen patients were included in a randomized crossover trial of enalapril, 20 mg daily, and diltiazem, 120 mg daily, for 6 weeks each. Blood pressure was measured by ambulatory blood pressure recording. During the washout phase, the acute effect of nifedipine, 10 mg p.o., and enalaprilat, 5 mg i.v., was evaluated. Nifedipine and enalaprilat reduced blood pressure equally well. The long-term blood pressure reduction induced by enalapril and diltiazem was similar. The acute blood pressure response to a given drug was not a good predictor of the result obtained with long-term therapy. No age dependency of the antihypertensive effect of either drug class was apparent. There was no evidence that a good response to one drug excluded a similarly good response to the other.     

Endothelial dysfunction, angiotensin-converting enzyme inhibitors and calcium antagonists

The endothelium plays a crucial role in the pathogenesis of cardiovascular disease. Endothelial function is attenuated by the presence of different well known cardiovascular risk factors. Evaluation of endothelial vasodilator function serve as an index integrating the overall stress imposed by cardiovascular risk factors and reinforce the suggestion that endothelial dysfunction is an early marker of cardiovascular disease that precedes clinical manifestations. Angiotensin-converting enzyme inhibitors have been shown to reduce the cardiovascular mortality, an effect that could be the consequence of an improvement in the endothelial function. Recent studies have shown that a calcium antagonist might improve the endothelial function, however, there is controversy about this action and also about the potential mechanisms for the effect of a calcium antagonist in the regulation of endothelial function.     

Clinical efficacy and tolerability of candesartan cilexetil. Candesartan Study Groups in Japan

Clinical trials of candesartan cilexetil conducted in Japan are reviewed. Candesartan cilexetil inhibited the pressor response to intravenous angiotensin II in healthy volunteers, with peak effects observed at 4 or 8 h after oral dosing; suppressing effects persisted up to 24 h. In 14 multicentre studies with 928 hypertensive patients treated for 8 to 12 weeks, candesartan cilexetil had an efficacy rate (reduction of systolic/diastolic blood pressure > or = 20/10 mm Hg and/or mean blood pressure > or = 13 mm Hg) of 72% and 63%, and an adverse effect rate of 9.9% and 7.3%, in patients with mild-to-moderate essential hypertension and those with impaired renal function, respectively. When data for elderly patients were analysed, there was no difference in efficacy and tolerability compared to non-elderly patients. In a double-blind comparative study, candesartan cilexetil was superior to enalapril in hypertensive patients: efficacy rate, 74% vs 66% (NS); adverse symptom rate, 10.4% vs 27.3% (P < 0.01); incidence of cough, 1.5% vs 14.8% (P < 0.01). Treatment with 2-8 mg of candesartan cilexetil once daily for 8 to 12 weeks reduced the left ventricular mass index without deterioration of cardiac function. In conclusion, 4-12 mg of candesartan cilexetil once daily is effective and well tolerated in patients with essential hypertension, including elderly patients, those with severe hypertension, and hypertensive patients with renal insufficiency. Its improved tolerability profile over angiotensin-converting enzyme inhibitors, as well as its end-organ protective effects, suggest that candesartan cilexetil is useful as a first-line antihypertensive drug.