Superior stroke prevention with angiotensin receptor blockers compared with other antihypertensive drugs

INTRODUCTION

Stroke is a major cause of death and disability and its incidence is linearly increased with the elevation of blood pressure (BP) and the advancement of age in both men and women, with its incidence being higher in older subjects, the blacks and women.

AREAS COVERED

The annual worldwide incidence of stroke is 7.6 million for subjects ≥ 20 years of age with the average direct and indirect annual costs of stroke care, is expected to be $94.3 billion between 2014 and 2015. With respect to the cause of stroke, this is multifactorial, due to atherosclerotic heart disease, inflammation, atrial fibrillation, and hypertension with the latter being the most important cause. Therefore, control of BP is the major factor for its prevention. In order to get a better perspective on the current management of stroke, a Medline search of the English literature was conducted between 2014 and 2022 and 26 pertinent papers were selected.

EXPERT OPINION

Review of data from the selected papers demonstrated that control of SSBP < 130 mmHg was better in stroke prevention than SBP 130-140 mmHg for primary and secondary strokes. Among the drugs used, angiotensin receptor blockers provided superior stroke prevention compared to angiotensin converting enzyme inhibitors and other antihypertensive drugs.

Beta-blockers and cardiovascular outcomes in dialysis patients: a cohort study in Ontario, Canada

BACKGROUND

Beta-blockers may be cardioprotective in patients receiving chronic dialysis. We examined cardiovascular outcomes among incident dialysis patients receiving beta-blocker therapy.

METHODS

We conducted a retrospective cohort study employing linked healthcare databases in Ontario, Canada. We studied all consecutive chronic dialysis patients aged≥66 years who initiated dialysis between 1 July 1991 and 31 July 2007. Patients were divided into three groups according to new medication use after the initiation of chronic dialysis. The three groups were patients initiated on beta-blockers, calcium channel blockers and statins only. Patients in the beta-blocker and calcium channel blocker groups could also be concurrently receiving a statin. The primary outcome was time to a composite endpoint of death, myocardial infarction, stroke or coronary revascularization.

RESULTS

There were a total of 1836 patients (504 beta-blocker, 570 calcium channel blocker and 762 statin-only users). Compared to statin-only use, beta-blocker use was not associated with improved cardiovascular outcomes [adjusted hazard ratio (aHR) 1.07, 95% confidence interval (CI) 0.92-1.23]. As expected, calcium channel blocker use was also not associated with improved cardiovascular outcomes (aHR 0.91, 95% CI 0.79-1.06). Among all subgroup analyses by beta-blocker attributes, only high-dose beta-blocker therapy was associated with better cardiovascular outcomes as compared to low-dose beta-blockers (aHR 0.50, 95% CI 0.29-0.88).

CONCLUSIONS

We observed no beneficial effect of beta-blocker use among patients receiving chronic dialysis relative to our comparator groups. Given current uncertainty around the cardioprotective benefits of beta-blockers in patients receiving dialysis, a large randomized clinical trial is warranted.

Hypertension and its management in countries in Africa and the Middle East, with special reference to the place of β-blockade

BACKGROUND

The prevalence and clinical consequences of hypertension in countries in Africa and the Middle East have not been studied as well as in other regions.

SCOPE

We have reviewed the literature on the epidemiology and management of hypertension and related cardiovascular complications in countries within Africa and the Middle East. A PubMed search for countries in the region and 'hypertension' was supplemented by articles identified from reviews, and by literature suggested by the authors.

FINDINGS

The prevalence of hypertension is >20% in some countries in the Middle East and Africa, despite an average population age that is some 10-15 years lower than those of developed countries. Hypertension in these countries is associated with an increased risk of cardiovascular risk factors and cardiovascular disease, as elsewhere. Awareness rates of hypertension are low. Hypertension and its complications are undertreated, and mortality rates from cardiovascular disease are higher than in developed countries.

CONCLUSION

Available resources should be brought to bear on the management of hypertension in these countries. In particular, a recent downgrading of the importance of β-blockers in hypertension management guidelines needs to be reassessed. These agents are as effective as other antihypertensive classes both on blood pressures and on cardiovascular event rates. General concerns over an increased rate of new-onset diabetes with β-blockers have been overstated, although these agents should be avoided in metabolic syndrome.

Current role of beta-blockers in the treatment of hypertension

IMPORTANCE OF THE FIELD

It is important to know which patients with hypertension will benefit from beta-blocker therapy and which beta-blockers should be used in the treatment of hypertension to reduce cardiovascular events and mortality.

AREAS COVERED IN THIS REVIEW

Studies between 1981 and 2009 using a Medline search are reported. Beta-blockers should be used to treat hypertension in patients with previous myocardial infarction, acute coronary syndromes, angina pectoris, congestive heart failure, ventricular arrhythmias, supraventricular tachyarrhythmias, diabetes mellitus, after coronary artery bypass graft surgery, and in patients who are pregnant, have thyrotoxicosis, glaucoma, migraine, essential tremor, perioperative hypertension, or an excessive blood pressure response after exercise.

WHAT THE READER WILL GAIN

The use of beta-blockers as first-line therapy in patients with primary hypertension has been controversial. However, the 2009 guidelines of the European Society of Hypertension state that large-scale meta-analyses of available data confirm that diuretics, beta-blockers, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers and calcium channel blockers do not significantly differ in their ability to lower blood pressure and to exert cardiovascular protection both in elderly and in younger patients.

TAKE HOME MESSAGE

The key message of this paper is that atenolol should not be used as an antihypertensive drug and that the degree of reduction of mortality, myocardial infarction, stroke and congestive heart failure by antihypertensive therapy is dependent on the degree of lowering of aortic blood pressure. Newer vasodilator beta-blockers such as carvedilol and nebivolol may be more effective in reducing cardiovascular events than traditional beta-blockers, but this needs to be investigated by controlled clinical trials.