Comparison of lercanidipine plus hydrochlorothiazide vs. lercanidipine plus enalapril on micro and macrocirculation in patients with mild essential hypertension

Dihydropyridine calcium channel blockers may possess antioxidant properties, and might improve micro and macrovascular structure and function. Combination treatment with an ACE inhibitor may have additional advantages, compared with a thiazide diuretic. The aim of the present study is to investigate the effects of a short-term treatment with lercanidipine, and to compare two combination treatments: lercanidipine + enalapril vs. lercanidipine + hydrochlorothiazide on structural alterations in retinal arterioles, on skin capillary density and on large artery distensibility. Thirty essential hypertension patients are included in the study, and treated for 4 weeks with lercanidipine 20 mg per day orally. Then, they were treated for 6 months with lercanidipine + enalapril (n = 15) or lercanidipine + hydrochlorothiazide (n = 15) combinations. Investigations were performed on basal condition, after appropriate wash out of previous treatments, after 4 weeks of lercanidipine monotherapy treatment, and at the end of the combination treatment. Non-invasive measurements of wall-to-lumen ratio (WLR) and other morphological parameters of retinal arterioles were performed using either scanning laser Doppler flowmetry or adaptive optics. Capillary density was evaluated by capillaroscopy, while pulse wave velocity was measured, and central blood pressures were assessed by pressure waveform analysis. A significant improvement of WLR and other indices of retinal artery structure is observed with both technical approaches after treatment with lercanidipine alone, with a further improvement after treatment with lercanidipine + enalapril, while after treatment with lercanidipine + hydrochlorothiazide, the improvement is partially blunted. Central systolic and diastolic blood pressures are similarly reduced by both therapeutic strategies. Capillary density is increased only after treatment with lercanidipine + enalapril. In conclusion, lercanidipine both in monotherapy and in combination with enalapril but not with hydrochlorothiazide is able to improve microvascular structure; on the other hand, a decrease in central blood pressure is observed with both therapeutic combinations.

Triple Combination Therapies Based on Olmesartan: A Personalized Therapeutic Approach to Improve Blood Pressure Control

Recent epidemiological surveys have demonstrated that effective and sustained blood pressure (BP) control is achieved in a relatively small proportion of treated hypertensive patients. Indeed, treatment of hypertension represents a key strategy for preventing coronary artery disease, stroke, congestive heart failure and cardiovascular death. Several interventions have been proposed by international guidelines for ameliorating hypertension management and control, mostly including integrated and multi-dimensional pharmacological and non-pharmacological strategies. In particular, numerous evidence demonstrated that a more extensive use of combination therapy may represent a valid therapeutic option for treating hypertensive patients at different risk profile. This strategy has been definitely strengthened by the availability of single pill fixed-dose combinations. Among potential combination therapies, those based on the association of renin-angiotensin system antagonists, thiazide diuretics and calcium channel blockers are very effective in lowering BP levels and well tolerated. We will provide here an overview of clinical evidence supporting the use of triple combination therapy, with a focus on that based on olmesartan medoxomil, a thiazide diuretic (hydrochlorothiazide) and a calcium channel blocker (amlodipine besylate), which is available in multiple dosages. Finally, in view of the recognised importance of single-pill combination therapy for treating hypertension, we will examine the potential benefits of dual (fixed) combination therapy based on olmesartan medoxomil with either thiazide diuretic hydrochlorothiazide or calcium channel blocker amlodipine in terms of efficacy, safety and tolerability profile.

Vascular effects of the lercanidipine/enalapril combination: clinical relevance

Hypertension is associated with alterations in the vascular structure, which in turn enhance the risk of cardiovascular events. Notably, anti-hypertensive treatment may prevent or regress the changes of arterial wall structures. Lercanidipine is a third-generation CCB with peculiar pharmaceutical properties. Enalapril is an effective drug acting on the renin-angiotensin-aldosterone axis. This commentary discusses the vascular effects of the lercanidipine/enalapril combination, and comments on their potential clinical relevance.

Effect of antihypertensive treatment on microvascular structure, central blood pressure and oxidative stress in patients with mild essential hypertension

BACKGROUND

It has been previously demonstrated that dihydropyridine calcium channel blockers may possess antioxidant properties and might improve vascular structure. Combination treatment with an angiotensin-converting enzyme inhibitor may have additional advantages, compared with a thiazide diuretic, in this regard. The aim of the present study was, therefore, to investigate the effects of a short-term treatment with lercanidipine, and to compare two combination treatments: lercanidipine + enalapril vs. lercanidipine + hydrochlorothiazide on structural alterations in retinal arterioles, on skin capillary density and on large artery distensibility.

PATIENTS AND METHODS

Twenty essential hypertensive patients were included in the study and treated for 4 weeks with lercanidipine 20 mg per day orally. Then they were treated for 6 months with lercanidipine + enalapril (n=10) or lercanidipine + hydrochlorothiazide (n=10) combinations. Investigations were performed in basal condition, after appropriate washout of previous treatments, after 4 weeks of lercanidipine monotherapy treatment, and at the end of the combination treatment. Non-invasive measurements of wall-to-lumen ratio (W/L) and other morphological parameters of retinal arterioles using scanning laser Doppler flowmetry were performed (Heidelberg Retina Flowmeter, Heidelberg Engineering). Capillary density was evaluated by capillaroscopy, whereas pulse wave velocity and central blood pressure were assessed by the Sphygmo-Cor device (AtCor Medical West Ryde, Australia).

RESULTS

A significant improvement of W/L and of other indices of retinal artery structure was observed after treatment with lercanidipine alone, with a further improvement after treatment with lercanidipine + enalapril, whereas after treatment with lercanidipine + hydrochlorothiazide the improvement was no longer observed. A similar behaviour was observed for central SBP and DBP. Capillary density was increased only after treatment with lercanidipine + enalapril.

CONCLUSION

Lercanidipine both in monotherapy and in combination with enalapril, was able to improve microvascular structure and to decrease central blood pressure, being thus a useful approach for both reducing blood pressure and improving vascular alterations in hypertension.

Triple combination therapy to improve blood pressure control: experience with olmesartan-amlodipine-hydrochlorothiazide therapy

INTRODUCTION

Effective treatment of hypertension is a key strategy for preventing and reducing the burden of hypertension-related cardiovascular diseases. In spite of these well-established concepts, hypertension remains poorly controlled, worldwide. Among the different pharmacological strategies required to improve blood pressure (BP) control, a more extensive use of combination therapy is progressively emerging as a cornerstone of a more effective treatment of hypertension. Among different drug combinations currently available for the clinical management of hypertension, those based on the association of drugs inhibiting the renin-angiotensin system, thiazide diuretics and calcium channel blockers have demonstrated to be very effective in lowering both systolic and diastolic, clinic and 24-h ambulatory BP levels with a good tolerability and safety profile.

AREAS COVERED

In the present manuscript the authors provide an overview of the evidence supporting the use of triple combination therapy with different classes of antihypertensive drugs, with a particular focus on those based on olmesartan medoxomil, a thiazide diuretic (hydrochlorothiazide) and a calcium channel blocker (amlodipine besylate).

EXPERT OPINION

Available data indicate that triple combination therapy based on olmesartan provides effective and sustained clinical and 24-h BP control in a high proportion of individuals among a broad range of hypertensive patients.

Rationale for triple fixed-dose combination therapy with an angiotensin II receptor blocker, a calcium channel blocker, and a thiazide diuretic

Hypertension is a growing global health problem, and is predicted to affect 1.56 billion people by 2025. Treatment remains suboptimal, with control of blood pressure achieved in only 20%-35% of patients, and the majority requiring two or more antihypertensive drugs to achieve recommended blood pressure goals. To improve blood pressure control, the European hypertension guidelines recommend that angiotensin II receptor blockers (ARBs) or angiotensin-converting enzyme inhibitors (ACEIs) are combined with calcium channel blockers (CCBs) and/or thiazide diuretics. The rationale for this strategy is based, in part, on their different effects on the renin-angiotensin system, which improves antihypertensive efficacy. Data from a large number of trials support the efficacy of ACEIs or ARBs in combination with CCBs and/or hydrochlorothiazide (HCTZ). Combining two different classes of antihypertensive drugs has an additive effect on lowering of blood pressure, and does not increase adverse events, with the ARBs showing a tolerability advantage over the ACEIs. Among the different ARBs, olmesartan medoxomil is available as a dual fixed-dose combination with either amlodipine or HCTZ, and the increased blood pressure-lowering efficacy of these two combinations is proven. Triple therapy is required in 15%-20% of treated uncontrolled hypertensive patients, with a renin-angiotensin system blocker, CCB, and thiazide diuretic considered to be a rational combination according to the European guidelines. Olmesartan, amlodipine, and HCTZ are available as a triple fixed-dose combination, and significant blood pressure reductions have been observed with this regimen compared with the possible dual combinations. The availability of these fixed-dose combinations should lead to improvement in blood pressure control and aid compliance with long-term therapy, optimizing the management of this chronic condition.

Modern clinical management of arterial hypertension: fixed or free combination therapies?

Blood pressure control is a key element in any cardiovascular prevention strategy. However, it is also one of the least frequently achieved goals in modern strategies for the clinical management of cardiovascular diseases, resulting in high impact in terms of cardiovascular morbidity and mortality. Among different factors that can be identified as the causes of poor blood pressure (BP) control in the general population of patients with hypertension, the excessive use of monotherapy, as opposed to combination therapy, is arguably one of the most significant. In this perspective, the use of combination therapies having synergic and complementary actions has been shown to reduce BP levels to increase the percentage of patients who respond to antihypertensive treatment and achieve the recommended BP targets. Moreover, recent studies have demonstrated that these strategies provide effective protection against hypertension-related organ damage, as well as a significant reduction of major cardiovascular events. While currently available evidence supports an increasingly important role of combination therapies compared with monotherapies, several other issues remain to be clarified. Among these, it has not yet been clearly established which classes of drugs should be considered for combination strategies, at what doses each component should be used, and whether combination strategies may be definitively considered as a first choice for the treatment of hypertensive patients at cardiovascular risk. Another relevant aspect concerns the choice between fixed and free combination therapies. This article discusses and analyses the different factors that may contribute to achieve effective BP control. In particular, the potential benefits and drawbacks associated with the use of fixed versus free combination therapies for hypertension treatment will be examined and discussed. The benefits of using combination strategies based on drugs that antagonize the renin-angiotensin system and dihydropyridine calcium antagonists will also be discussed, with a particular focus on amlodipine besylate combination therapies.