Progressive effects of valsartan compared with amlodipine in prevention of diabetes according to categories of diabetogenic risk in hypertensive patients: The VALUE trial

Angiotensin II receptor antagonists in acute coronary syndromes

BACKGROUND

It is well known that inappropriate or exaggerated activity of the renin-angiotensin system might contribute to the development of systemic hypertension with consequent organ injury and associated increased risk of acute cardiovascular (CV) diseases. This review will discuss evidence form basic research and clinical studies, investigating the efficacy of angiotensin II receptor blockers (ARBs) in the management of acute coronary syndromes (ACS).

MATERIALS AND METHODS

This narrative review is based on the material found on MEDLINE and PubMed up to June 2013. We looked for the terms 'angiotensin, AT1 receptor, ACE inhibitors' in combination with 'acute coronary syndromes, acute myocardial infarction, pathophysiology'.

RESULTS

Preclinical studies showed relevant protective effects of ARBs to reduce adverse cardiac remodelling in animal models of acute cardiac ischaemia. However, although recommended in Consensus guidelines as a good alternative to angiotensin-converting enzyme inhibitors (ACEIs), clinical studies did not confirm a superior efficacy of the ARBs as compared to ACEIs. As a matter of fact for some authors, these drugs might potentially have deleterious effects increasing the CV risk.

CONCLUSIONS

Emerging evidence from clinical trials suggests that the use of ARBs in ACS might be controversial, and caution should be used for their clinical use to replace ACEIs in ACS.

Antihypertensive treatment in diabetic patients. Review of current data

Thirty to 50% of diabetic patients suffer from hypertension, exhibiting increased cardiovascular risk. In the present article we review key studies regarding the current knowledge for blood pressure (BP) goals in people with diabetes, the treatment used and the possible diabetogenic effects of antihypertensive drugs, as well as the beneficial and non-beneficial combinations of antihypertensive drugs in diabetic patients. Early placebo controlled trials proved the beneficial outcome of BP lowering in diabetic patients with initially high BP levels. More recent trials examined the impact of intensive compared to less intensive BP goals in diabetic populations. However, initial BP goals had significant differences from final achieved BP levels. Accordingly, current data support initiation of antihypertensive drug treatment in all patients with diabetes and systolic BP ≥ 140 mmHg, with the aim to lower it consistently <140 mmHg, although how far below 140 mmHg the systolic BP goal should be is not clear. Available literature indicates that more than one drug is commonly used to achieve target BP. Drugs acting on the renin-angiotensin-aldosterone axis have been shown to act protectively on diabetic nephropathy, while β-blockers and diuretics seem to have a diabetogenic effect. Interestingly, recent studies examining the role of combined use of available renin-angiotensin-aldosterone axis blockers versus its separate use exhibited an increased incidence of adverse outcome in diabetic patients who used combinations of drugs that act against renin-angiotensin-aldosterone system. More studies need to be conducted in order to establish the best combination therapy to reduce diabetic complications.

Effects of antihypertensive treatments on incidence of diabetes: a case-control study

AIMS

Aim of this case-control study is the assessment of the relationship between antihypertensive treatment and incidence of diabetes in an unselected cohort of subjects participating in a screening program for diabetes.

METHODS

A case-control study nested within a cohort of nondiabetic subjects with a mean follow-up of 27.7 ± 11.3 months was performed, comparing 40 cases of incident diabetes and 160 controls matched for age, sex, body mass index, fasting plasma glucose, 2-h post-load glycemia, smoking and alcohol abuse.

RESULTS

When considering antihypertensive treatment at enrolment, a lower proportion of cases was exposed to ACE-inhibitors/angiotensin receptor blockers (ACE-i/ARB) in comparison with controls. A non-significant trend toward a higher exposure to diuretics, which were mainly represented by thiazide diuretics, was observed in cases. In a multivariate analysis, including both ACE-i/ARB and diuretics, a protective effect of ACEi/ARB, and an increased risk with diuretics were observed. Similar results were obtained in alternative models, after adjusting for systolic and diastolic blood pressure at enrolment, diagnosis of hypertension, concurrent treatment with β-blockers or calcium-channel blockers, and number of antihypertensive medications.

CONCLUSIONS

Diuretics seem to be associated with a higher incidence of diabetes, whereas treatment with ACEi/ARB could have a protective effect.

Angiotensin receptor blockers for prevention of new-onset type 2 diabetes: a meta-analysis of 59,862 patients

BACKGROUND

Angiotensin receptor blockers (ARBs) have been linked to reduced risk of new-onset diabetes, but the evidence was insufficient.

OBJECTIVE AND METHODS

The aim of this study was to evaluate the effect of ARBs on the development of new-onset type 2 diabetes. Randomized controlled trials (RCTs) about ARBs and new-onset diabetes were identified by electronic and manual searches.

RESULTS

Eleven RCTs with 79,773 patients (59,862 non-diabetic patients at baseline) were included in this study. Compared with control group, incidence of new-onset diabetes was significantly reduced in ARBs group [OR 0.79, (0.74, 0.84)] and various categories of ARBs subgroup. ARBs were associated with significant reduction in the risk of new-onset diabetes compared with placebo [OR 0.83, (0.78, 0.89)], beta-blocker [OR 0.73, (0.62, 0.87)], calcium channel blocker [OR 0.76, (0.68, 0.85)] and non-ARB [OR 0.57, (0.36, 0.91)]. ARBs were associated with significant reduction in the risk of new-onset diabetes in patients with hypertension [OR 0.74, (0.68, 0.81)], heart failure [OR 0.70, (0.50, 0.96)], impaired glucose tolerance [OR 0.85, (0.78, 0.92)] or cardiocerebrovascular diseases [OR 0.84, (0.72, 0.97)]. Compared with control group, incidence of new-onset diabetes was significantly reduced in ARBs group, irrespective of achieved blood pressure level. ARBs were associated with a lower incidence of new-onset diabetes in Western population [OR 0.81, (0.76, 0.85)] and Japanese population [OR 0.61, (0.48, 0.79)].

CONCLUSION

There is sufficient evidence that ARBs have beneficial effect in preventing new-onset type 2 diabetes. ARBs should be considered in patients with high risk of developing diabetes.

Prediabetes: the importance of early identification and intervention

Prediabetes is a state of abnormal glucose homeostasis characterized by the presence of impaired fasting glucose, impaired glucose tolerance, or both. Individuals with prediabetes are at increased risk for type 2 diabetes, compared with individuals with normal glucose values (normal fasting plasma glucose, < 100 mg/dL [5.6 mmol/L]). The increased risk for cardiovascular disease in prediabetes is multifactorial, with etiologies including insulin resistance, hyperglycemia, dyslipidemia, hypertension, systemic inflammation, and oxidative stress. The preferred treatment is intensive lifestyle management and aggressive pharmacologic therapies directed toward individual coronary heart disease risk factors. The use of antihyperglycemic agents in this setting is a topic of intense debate. This review discusses the pathophysiology of prediabetes and its clinical implications, highlighting the importance of early identification and intervention.