Differences in glucose tolerance between fixed-dose antihypertensive drug combinations in people with metabolic syndrome

Spironolactone prevents chlorthalidone-induced sympathetic activation and insulin resistance in hypertensive patients

Recent studies from our laboratory indicate that chlorthalidone triggers persistent activation of the sympathetic nervous system and promotes insulin resistance in hypertensive patients, independent of serum potassium. Mechanisms underlying these adverse effects of chlorthalidone remain unknown, but increasing evidence in rodents suggests the role of angiotensin and aldosterone excess in inducing both sympathetic overactivity and insulin resistance. Accordingly, we conducted studies in 17 subjects with untreated stage 1 hypertension, measuring sympathetic nerve activity at baseline and after 12 weeks of chlorthalidone alone (25 mg/d), chlorthalidone plus spironolactone, and chlorthalidone plus irbesartan, using randomized crossover design. We found that chlorthalidone alone decreased 24-hour ambulatory blood pressure from 135±3/84±2 to 124±2/78±2 mm Hg and significantly increased sympathetic nerve activity from baseline (from 41±3 versus 49±4 bursts per minute; P<0.01). The addition of spironolactone to chlorthalidone returned sympathetic nerve activity value to baseline (42±3 bursts per minute; P>0.05), whereas the addition of irbesartan failed to alter the sympathetic nerve activity response to chlorthalidone in the same subjects (52±2 bursts per minute; P<0.01) despite a similar reduction in ambulatory blood pressure (121±2/75±2 and 121±2/75±2 mm Hg, respectively). Chlorthalidone alone also increased indices of insulin resistance, which was not observed when used in combination with spironolactone. In conclusion, our study demonstrates beneficial effects of spironolactone in attenuating both chlorthalidone-induced sympathetic activation and insulin resistance in humans, independent of blood pressure reduction. Because sympathetic overactivity and insulin resistance contribute to the poor prognosis in patients with cardiovascular disease, combination therapy of chlorthalidone with mineralocorticoid receptor antagonists may constitute a preferable regimen than chlorthalidone alone in hypertensive patients.

A double-blind, placebo-controlled, crossover trial comparing the effects of amiloride and hydrochlorothiazide on glucose tolerance in patients with essential hypertension

Hypertension guidelines advise limiting the dose of thiazide diuretics and avoiding combination with β-blockade, because of increased risk of diabetes mellitus. We tested whether changes in the 2-hour oral glucose tolerance test could be detected after 4 weeks of treatment with a thiazide and could be avoided by switching to amiloride. Two double-blind, placebo-controlled, crossover studies were performed. In study 1 (41 patients), we found that changes in glucose during a 2-hour oral glucose tolerance test could be detected after 4 weeks of treatment with bendroflumethiazide. In study 2, 37 patients with essential hypertension received, in random order, 4 weeks of once-daily treatment with hydrochlorothiazide (HCTZ) 25 to 50 mg, nebivolol 5 to 10 mg, combination (HCTZ 25-50 mg+nebivolol 5-10 mg), amiloride (10-20 mg), and placebo. Each drug was force titrated at 2 weeks and separated by a 4-week placebo washout. At each visit, we recorded blood pressure and performed a 75-g oral glucose tolerance test. Primary outcome was the difference in glucose (over the 2 hours of the oral glucose tolerance test) between 0 and 4 weeks, when HCTZ and amiloride were compared by repeated-measures analysis. For similar blood pressure reductions, there were opposite changes in glucose between the 2 diuretics (P<0.0001). Nebivolol did not impair glucose tolerance, either alone or in combination. There was a negative correlation between Δpotassium and Δ2-hour glucose (r=-0.28; P<0.0001). In 2 crossover studies, 4 weeks of treatment with a thiazide diuretic impaired glucose tolerance. No impairment was seen with K(+)-sparing diuretic or β(1)-selective blockade. Substitution or addition of amiloride may be the solution to preventing thiazide-induced diabetes mellitus.

Evidence-based hypertension treatment in patients with diabetes

Both impaired glucose tolerance and diabetes are associated with substantially increased prevalence of hypertension, cardiovascular and renal disease. The goal for hypertension treatment in diabetic patients is in evolution, because of recent clinical trials. For example, the results of the recent Action to Control Cardiovascular Risk in Diabetes-BP Arm (ACCORD BP) trial failed to show an additional benefit on cardiovascular event reduction at a mean systolic BP of 119 mm Hg. A post hoc analysis of 6,400 patients with type 2 diabetes from the International Verapamil-Trandolapril Study (INVEST) also failed to show additional cardiovascular risk reduction among patients who achieved a BP <130/80 mm Hg. While the evidence fails to support a lower BP goal to reduce coronary events, there was a risk reduction in stroke events both in ACCORD and the Appropriate Blood Pressure Control in NIDDM (ABCD) trial. A number of other clinical trials also demonstrate that when systolic pressures fall to less than 130 mm Hg, a reduction in stroke but not coronary disease events occurs. Thus, the precise BP goal for diabetic patients remains unresolved. We would posit that a BP goal of 135/85 mm Hg may be a reasonable compromise when viewing the impact of BP reduction on composite stroke and coronary artery disease in extant trials.

Potassium and risk of Type 2 diabetes

The rising incidence and prevalence of Type 2 diabetes worldwide requires us to try to identify the determinants of this epidemic and to identify improved measures to prevent and treat this condition. While obesity is a major risk factor for diabetes, there are other risk factors that could potentially be corrected more easily. Potassium, both serum levels and to a lesser extent dietary intake levels, has been associated with incident diabetes. Lower levels of potassium have been found to be associated with a higher risk of diabetes in some studies. This article will review the literature available describing these associations and will help to identify where further research is needed.

Impact of trandolapril therapy and its combination with a calcium channel blocker on plasma adiponectin levels in patients with type 2 diabetes and hypertension

INTRODUCTION

Adiponectin is secreted from adipose tissue and exhibits a protective effect against cardiovascular disease; plasma adiponectin concentrations are decreased in type 2 diabetic and in hypertensive patients.

OBJECTIVE

The aim of this study was to compare the effect of trandolapril (T) and its fixed-dose combination with verapamil (FDTV) on adiponectin levels in hypertensive type 2 diabetic patients.

METHODS

A total of 40 type 2 diabetic patients with never-treated hypertension were randomly assigned to two groups. One group received FDTV 180 mg + T 2 mg, once a day; the other group received T 2 mg once a day, administered for 3 months in both groups. Adiponectin was measured by enzyme-linked immunosorbent assay (ELISA) at the beginning and end of the study. Patients were evaluated monthly for blood pressure, fasting serum glucose and adverse events. Statistical analysis was performed with analysis of variance (ANOVA).

RESULTS

All patients experienced a significant reduction of blood pressure. Both therapeutics regimens increased the levels of adiponectin, However, FDTV produces a higher increase in the levels of the hormone (8.15 ± 4.6 to 10.96 ± 5.6 µg/ml) when compared with the T treatment (7.64 ± 3.8 to 8.92 ± 4.4 µg/ml), p < 0.05. None of the patients suffered adverse events.

CONCLUSION

Our results show that the addition of FDTV to T produced a greater increase on adiponectin levels than trandolapril alone.

Switching therapy from variable-dose multiple pill to fixed-dose single-pill combinations of angiotensin II receptor blockers and thiazides for hypertension

The efficacy and tolerability of switching therapy from free combinations of angiotensin II receptor blocker (ARB) and thiazide (A/T) to a fixed-dose of losartan and hydrochlorothiazide (L/H) has not been evaluated in Japan. We examined effects of switching therapy from variable-dose multiple-pill A/T to a fixed-dose L/H on blood pressure (BP) along with medication adherence and the degree of satisfaction in 91 hypertensive outpatients (mean age, 65.2 ± 9.6 years). After 6 months, a significant BP reduction (132 ± 9/76 ± 10 vs. 126 ± 12/72 ± 11 mm Hg), along with an improvement of attaining target BP (44.0 vs. 61.5%) and that of adherence, were observed. The magnitude of BP reduction in the participants increased their degree of satisfaction more significantly than in the participants who worsened their degree of satisfaction. The estimated glomerular filtration rate and the serum uric acid (UA) level decreased slightly but significantly. The hemoglobin A1c of participants with diabetes mellitus increased slightly but significantly. In conclusion, a switch in therapy from variable-dose, multiple-pill A/T combinations to a fixed-dose, single-pill L/H was effective in decreasing BP and serum UA in Japanese clinical practice. Metabolic side effects of L/H in patients with diabetes mellitus remain to be investigated.

Valsartan improves {beta}-cell function and insulin sensitivity in subjects with impaired glucose metabolism: a randomized controlled trial

OBJECTIVE

Recently, the Nateglinide and Valsartan in Impaired Glucose Tolerance Outcomes Research Trial demonstrated that treatment with the angiotensin receptor blocker (ARB) valsartan for 5 years resulted in a relative reduction of 14% in the incidence of type 2 diabetes in subjects with impaired glucose metabolism (IGM). We investigated whether improvements in β-cell function and/or insulin sensitivity underlie these preventive effects of the ARB valsartan in the onset of type 2 diabetes.

RESEARCH DESIGN AND METHODS

In this randomized controlled, double-blind, two-center study, the effects of 26 weeks of valsartan (320 mg daily; n = 40) or placebo (n = 39) on β-cell function and insulin sensitivity were assessed in subjects with impaired fasting glucose and/or impaired glucose tolerance, using a combined hyperinsulinemic-euglycemic and hyperglycemic clamp with subsequent arginine stimulation and a 2-h 75-g oral glucose tolerance test (OGTT). Treatment effects were analyzed using ANCOVA, adjusting for center, glucometabolic status, and sex.

RESULTS

Valsartan increased first-phase (P = 0.028) and second-phase (P = 0.002) glucose-stimulated insulin secretion compared with placebo, whereas the enhanced arginine-stimulated insulin secretion was comparable between groups (P = 0.25). In addition, valsartan increased the OGTT-derived insulinogenic index (representing first-phase insulin secretion after an oral glucose load; P = 0.027). Clamp-derived insulin sensitivity was significantly increased with valsartan compared with placebo (P = 0.049). Valsartan treatment significantly decreased systolic and diastolic blood pressure compared with placebo (P < 0.001). BMI remained unchanged in both treatment groups (P = 0.89).

CONCLUSIONS

Twenty-six weeks of valsartan treatment increased glucose-stimulated insulin release and insulin sensitivity in normotensive subjects with IGM. These findings may partly explain the beneficial effects of valsartan in the reduced incidence of type 2 diabetes.

Hypertension 2010: what was new for the cardiologist?

IMPORTANCE OF THE FIELD

Despite extensive clinical research, still there is some uncertainty regarding management of hypertension, in particular initial and goal blood pressure levels and selection of optimal pharmacotherapy, as well as concomitant medications, to reduce other risk factors.

AREAS COVERED IN THIS REVIEW

An overview of recent findings from major clinical trials in hypertension (until July 2010), along with a reappraisal of the European Society of Hypertension 2009 guidelines.

WHAT THE READER WILL GAIN

Practical overview of the management of hypertension, including threshold and goal blood pressure in specific situations, choice of antihypertensive medications and indications for treatment of concomitant risk factors.

TAKE HOME MESSAGE

Primary benefits of antihypertensive therapy are mediated by blood pressure reduction and the majority of patients will require at least two drugs, with the preference of fixed-dose combinations for effective blood pressure control.

The role of Angiotensin receptor blocker and calcium channel blocker combination therapy in treating hypertension: focus on recent studies

Hypertension remains a significant health problem, affecting approximately 30% of the US population. Of these, only 36.8% have BP controlled to recommended levels of <140/90 mmHg for uncomplicated hypertension and <130/80 mmHg for patients with diabetes mellitus or renal disease. For those with uncontrolled hypertension, the risk of diabetes, renal disease, stroke, and cardiovascular disease is increased. Therapeutic options for the treatment of hypertension include several major classes of drugs: diuretics, β-adrenoceptor antagonists (β-blockers), ACE inhibitors, angiotensin II type 1 receptor antagonists (angiotensin receptor blockers [ARBs]), renin inhibitors, calcium channel blockers, and central sympatholytics, alone or in combination. Guidelines recommend thiazide diuretics as preferred first-line monotherapy. However, only 50% of patients will respond adequately to this therapy and the rest will require two or more antihypertensive agents to achieve BP goals. Clinical evidence demonstrates that some drugs have advantages when used in combination rather than as monotherapy. Drugs that block the renin-angiotensin-aldosterone system not only provide BP control but may also provide vascular protection and are metabolically neutral. This is a concise review of the safety and efficacy of ARBs in combination with amlodipine for the treatment of hypertension, with focus on the telmisartan-amlodipine combination. A MEDLINE search of the English literature from 2006 to 2009 of amlodipine in combination with ARBs revealed six publications, which are included in this review.

Olmesartan/amlodipine vs olmesartan/hydrochlorothiazide in hypertensive patients with metabolic syndrome: the OLAS study

We studied the effects of treatment with olmesartan/amlodipine and olmesartan/hydrochlorothiazide on inflammatory and metabolic parameters (including new-onset diabetes as a secondary endpoint) in non-diabetic hypertensive patients with metabolic syndrome (MetS). A total of 120 patients with MetS and stage I and II hypertension were randomized to olmesartan 20 mg/amlodipine 5 mg or olmesartan 20 mg/hydrochlorothiazide 12.5 mg. If target systolic blood pressure (<140 mm Hg) was not reached, doses were doubled after 13 weeks; doxazosin 4 mg was added after 26 weeks, and doubled after 39 weeks; follow-up ended at 78 weeks. At each visit, blood pressure (BP), fasting plasma glucose, insulin, adiponectin, tumour necrosis factor-α, C-reactive protein (CRP), intercellular adhesion molecule-1, vascular cell adhesion molecule-1, interleukins-1β, -6 and -8, and albuminuria were measured; BP was similarly reduced in both groups; 80% of patients reached target BP. Reductions in albuminuria were also similar (50%). Only olmesartan/amlodipine reduced the insulin resistance index (24%, P<0.01), increased plasma adiponectin (16%, P<0.05) and significantly reduced all of the inflammation markers studied, except CRP, which showed a similar reduction in each group. The risk of new-onset diabetes was significantly lower with olmesartan/amlodipine (P=0.02). Both olmesartan-based combinations were effective, but the amlodipine combination resulted in metabolic and anti-inflammatory effects that may have advantages over the hydrochlorothiazide combination.

Increasing the doses of both diuretics and angiotensin receptor blockers is beneficial in subjects with uncontrolled systolic hypertension

BACKGROUND

Blood pressure (BP) control is frequently difficult to achieve in patients with predominantly elevated systolic BP. Consequently, these patients frequently require combination therapy including a thiazide diuretic such as hydrochlorothiazide (HCTZ) and an agent blocking the renin-angiotensin-aldosterone system. Current clinical practice usually limits the daily dose of HCTZ to 25 mg. This often leads to the necessity of using additional antihypertensive agents to control BP in a high proportion of patients.

OBJECTIVES

To compare the efficacy of two doses of losartan (LOS)⁄HCTZ combinations in patients with uncontrolled ambulatory systolic hypertension after six weeks of treatment with LOS 100 mg⁄HCTZ 25 mg (LOS100⁄HCTZ25).

METHODS

Following a two- to four-week washout period, subjects with a mean clinic sitting systolic BP of 160 mmHg or higher and a mean ambulatory daytime systolic BP (MDSBP) of 135 mmHg or higher on LOS100⁄HCTZ25 (n=105; 33 women and 72 men) were randomly assigned to receive LOS 150 mg⁄HCTZ 25 mg (group 1; n=53) or LOS 150 mg⁄HCTZ 37.5 mg (LOS150⁄HCTZ37.5, group 2; n=52). The primary end point was the difference in MDSBP reductions.

RESULTS

At the end of the six-week treatment period, the respective additional decreases in MDSBP were 1.2 mmHg (P=0.335) on LOS 150 mg⁄HCTZ 25 mg and 5.6 mmHg (P<0.0001) on LOS150⁄HCTZ37.5 (difference of 4.4 mmHg; P=0.011). Daytime systolic ambulatory BP goal (lower than 130 mmHg) achievement tended to be higher (25% versus 17%; P=0.313) with LOS150⁄HCTZ37.5, while it was significantly higher (65% versus 43%; P=0.024) for mean daytime diastolic BP (lower than 80 mmHg). No deleterious metabolic changes were observed.

CONCLUSIONS

In patients with uncontrolled systolic ambulatory hypertension receiving LOS100⁄HCTZ25, increasing both HCTZ and LOS dosages simultaneously to LOS150⁄HCTZ37.5 may be an effective strategy that does not affect metabolic parameters.

Angiotensin receptor blocker/diuretic combination preserves insulin responses in obese hypertensives

BACKGROUND

Thiazide diuretics can impair glucose metabolism and increase new-onset diabetes. Adding an angiotensin receptor blocker to diuretics may protect against these metabolic effects; however, the mechanism of this protection is unclear.

METHOD

To explore potential mechanisms, a 16-week multicenter trial was conducted to ascertain the relative glucose metabolism effects of combined hydrochlorothiazide and angiotensin receptor blocker (valsartan) therapy compared with hydrochlorothiazide and calcium channel blocker (amlodipine) treatment in 412 centrally obese hypertensive individuals (BMI = 35 +/- 7 kg/m, seated BP = 159 +/- 8/94 +/- 8 mmHg, and mean age 56 years). Individuals were randomized to valsartan/hydrochlorothiazide, with force-titration to 320/25 mg or hydrochlorothiazide, with titration to hydrochlorothiazide 25 mg and amlodipine 10 mg, respectively. Changes from baseline to week 16 in fasting and 2-h postprandial glucose and insulin levels after an oral glucose load were measured.

RESULTS

At week 16, clinic blood pressure reductions were similar (P > 0.05) in both groups. Fasting and 2-h glucose levels increased (P < 0.05) with the amlodipine combination but not with the valsartan combination. In concert with these glucose responses, postprandial insulin increases from baseline were substantially greater with valsartan than with amlodipine plus hydrochlorothiazide group (P = 0.001). The glucose responses were inversely related to insulin responses at the study conclusion.

CONCLUSION

The novel observation of this investigation was that the combination of valsartan and hydrochlorothiazide was associated with greater glucose-stimulated insulin secretory and lesser glycemic excursion responses than the amlodipine combination group. Thus, this data suggests that adding an angiotensin receptor blocker attenuates the negative effects of thiazides on pancreatic beta-cell glucose-induced insulin secretion.

Combination therapy in hypertension: An update

Meticulous control of blood pressure is required in patients with hypertension to produce the maximum reduction in clinical cardiovascular end points, especially in patients with comorbidities like diabetes mellitus where more aggressive blood pressure lowering might be beneficial. Recent clinical trials suggest that the approach of using monotherapy for the control of hypertension is not likely to be successful in most patients. Combination therapy may be theoretically favored by the fact that multiple factors contribute to hypertension, and achieving control of blood pressure with single agent acting through one particular mechanism may not be possible. Regimens can either be fixed dose combinations or drugs added sequentially one after other. Combining the drugs makes them available in a convenient dosing format, lower the dose of individual component, thus, reducing the side effects and improving compliance. Classes of antihypertensive agents which have been commonly used are angiotensin receptor blockers, thiazide diuretics, beta and alpha blockers, calcium antagonists and angiotensin-converting enzyme inhibitors. Thiazide diuretics and calcium channel blockers are effective, as well as combinations that include renin-angiotensin-aldosterone system blockers, in reducing BP. The majority of currently available fixed-dose combinations are diuretic-based. Combinations may be individualized according to the presence of comorbidities like diabetes mellitus, chronic renal failure, heart failure, thyroid disorders and for special population groups like elderly and pregnant females.

Current concepts in combination therapy for the treatment of hypertension: combined calcium channel blockers and RAAS inhibitors

Recent guidelines for the management of hypertension recommend target blood pressures <140/90 mmHg in hypertensive patients, or <130/80 mmHg in subjects with diabetes, chronic kidney disease, or coronary artery disease. Despite the availability and efficacy of antihypertensive drugs, most hypertensive patients do not reach the recommended treatment targets with monotherapy, making combination therapy necessary to achieve the therapeutic goal. Combination therapy with 2 or more agents is the most effective method for achieving strict blood pressure goals. Fixed-dose combination simplifies treatment, reduces costs, and improves adherence. There are many drug choices for combination therapy, but few data are available about the efficacy and safety of some specific combinations. Combination therapy of calcium antagonists and inhibitors of the renin-angiotensin-aldosterone system (RAAS) are efficacious and safe, and have been considered rational by both the JNC 7 and the 2007 European Society of Hypertension – European Society of Cardiology guidelines for the management of arterial hypertension. The aim of this review is to discuss some relevant issues about the use of combinations with calcium channel blockers and RAAS inhibitors in the treatment of hypertension.

Trends in hypertension treatment in diabetes

This review discusses current concepts and future trends in the optimal control of elevated blood pressure and hypertension in persons with diabetes, specifically type 2 diabetes mellitus. Although the primary management for persons with type 2 diabetes mellitus, especially with lower levels of blood pressure elevation, is modification or reversal of adverse lifestyles, including weight management and increased physical activity, pharmacologic antihypertensive treatment is usually necessary to optimally control cardiovascular and renal risks. Therapies that modulate the renin-angiotensin-aldosterone system may be beneficial in reducing associated cardiovascular and renal diseases, but control of elevated blood pressure remains an essential target of any antihypertensive therapy. Blood pressure goal attainment, even with pharmacologic therapy, is distressingly low. Certain racial or ethnic groups in the United States have a higher prevalence of diabetes, and greater associated rates of hypertension are noted in African Americans, with increased cardiovascular morbidity and mortality. Clinical evidence may soon confirm or refute the outcomes benefit of blood pressure targets of 120/80 mm Hg or lower.

Should diuretics always be included as initial antihypertensive management in early-stage CKD?

PURPOSE OF REVIEW

This review focuses on the need for combined antihypertensive therapy drugs in patients with chronic kidney disease and the relevance of diuretics.

RECENT FINDINGS

Chronic kidney disease is a high-risk situation characterized by the presence of volume overload-related hypertension, micro/macroalbuminuria and other traditional and nontraditional risk factors. To achieve the blood pressure goal in these patients, combined antihypertensive therapy (including diuretics) is usually required.

SUMMARY

Extracellular volume expansion is an important, if not the most important, contributing factor to hypertension seen in chronic kidney disease. Protection against progression of renal dysfunction has two main requirements: strict blood pressure control and lowering proteinuria to values as near to normal as possible. Diuretics have been a useful tool to manage volume overload and to achieve strict blood pressure control in patients with chronic kidney disease. Albeit other blood pressure-lowering agents offer additional favorable effects independently of blood pressure changes, diuretics will continue to be used in these patients.

The role of fixed-dose combinations in the management of hypertension: focus on lercanidipine-enalapril

Achieving optimal blood pressure (BP) control is the most important single issue in the management of hypertension, and in most patients, it is difficult or impossible to achieve target levels with one drug. Blocking two or more regulatory systems provides a more effective and more physiologic reduction in BP, and current guidelines have recommended the use of combination therapy as first-line treatment, or early in the management of hypertension. Fixed-dose combination therapy is an efficacious, relatively safe and cost-effective treatment option in most patients with essential hypertension. Of note, the once-daily administration of a fixed-dose enalapril/lercanidipine, by bringing together two distinct and complementary mechanisms of action, reduces BP effectively and has the potential for improved target organ protection relative to either class agent alone.

[Hypertension 2007-2008]

Hypertension still represents a leading cause of mortality worldwide and a main modifiable risk factor for cardiovascular, cerebrovascular and renal diseases. Therefore, guideline writing groups have proposed new recommendations regarding diagnosis and treatment. Nevertheless, a series of large-scale clinical trials have been published thereafter. Their results, namely the risk associated with the combination of angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs), the benefits of an initial therapy with a fixed-dose combination of calcium channel blocker and ACE inhibitor, the effectiveness of blood pressure reduction in patients > 80 years, and the introduction of oral renin inhibitors in the market will enormously impact clinical practice.

Effectiveness and tolerability of fixed-dose combination enalapril plus nitrendipine in hypertensive patients: results of the 3-month observational, post-marketing, multicentre, prospective CENIT study

BACKGROUND AND OBJECTIVE

Monotherapy with any class of antihypertensive drug effectively controls blood pressure (BP) in only about 50% of patients. Consequently, the majority of patients with hypertension require combined therapy with two or more medications. This study aimed to evaluate the effectiveness (systolic BP [SBP]/diastolic BP [DBP] control) and tolerability of the fixed-dose combination enalapril/nitrendipine 10 mg/20 mg administered as a single daily dose in hypertensive patients.

METHODS

This was a post-authorization, multicentre, prospective, observational study conducted in primary care with a 3-month follow-up. Patients throughout Spain with uncontrolled hypertension (> or =140/90 mmHg for patients without diabetes mellitus, or > or =130/85 mmHg for patients with diabetes) on monotherapy or with any combination other than enalapril + nitrendipine, or who were unable to tolerate their previous antihypertensive therapy, were recruited. Change from previous to study treatment was according to usual clinical practice. BP was measured once after 5 minutes of rest in the sitting position. Therapeutic response was defined as follows: 'controlled' meant controlled BP (<140/90 mmHg for nondiabetic patients, or <130/85 mmHg for diabetic patients); 'response' meant controlled BP, or a decrease in SBP of > or =20 mmHg and in DBP of > or =10 mmHg. The main laboratory test parameters were documented at baseline and after 3 months. Patients aged >65 years, with diabetes, with isolated systolic hypertension (ISH; SBP > or =140 mmHg for patients without diabetes, SBP > or =130 mmHg for patients with diabetes) and who were obese (body mass index [BMI] > or =30 kg/m2) were analysed separately.

RESULTS

Of 6537 patients included, 5010 and 6354 patients were assessed in effectiveness and tolerability analyses, respectively. In the tolerability analysis population, there were 3023 men (47.6%) and 3321 women (52.4%). The mean (+/- SD) age of the tolerability analysis group was 62.8 (+/- 10.7) years. A total of 71.1% of the patients presented at least one clinical cardiovascular risk factor other than hypertension, with the most frequent being dyslipidaemia (42.3%), obesity (29.2%) and diabetes (23.9%). After 3 months of treatment, SBP and DBP showed mean (+/- SD) decreases of 26.5 (+/- 14.4) mmHg and 14.9 (+/- 9.0) mmHg, respectively, and 73.0% of patients responded to treatment while 40.9% achieved BP control (70.8%/36.1% in 2658 patients aged >65 years; 61.7%/46.8% in 1521 patients with diabetes; 55.3%/44.2% in 731 patients with ISH; 72.0%/36.4% in 1762 obese patients). Adverse events were reported in 10.8% of patients (n = 689). During the follow-up period, ten patients died and seven patients had serious adverse events; in no case was a causal relationship attributed to the study product.

CONCLUSIONS

The rate of SBP/DBP control achieved demonstrates the effectiveness of the fixed-dose enalapril/nitrendipine 10 mg/20 mg combination administered as a single daily dose in patients with essential hypertension not adequately controlled with monotherapy or with any combination other than enalapril + nitrendipine. The proportion and type of adverse events reported were as expected and have already been described for both components of the enalapril/nitrendipine 10 mg/20 mg combination. These results confirm the effectiveness of a strategy based on a fixed-dose enalapril/nitrendipine 10 mg/20 mg combination in reducing BP and achieving BP control goals.

Manidipine in hypertensive patients with metabolic syndrome: the MARIMBA study

OBJECTIVES

To evaluate the effects of manidipine versus amlodipine on blood pressure, albuminuria, insulin sensitivity, adiponectin, TNF-alpha and C-reactive protein in nondiabetic subjects with metabolic syndrome (ATP-III definition), including impaired fasting glucose (>5.6 mmol/l) and hypertension.

METHODS

In total, 64 patients were recruited and randomly assigned to manidipine 20 mg versus amlodipine 10 mg (for 12 +/- 2 weeks).

RESULTS

Blood pressure was reduced to a similar extent (p < 0.001) by both treatments. Albuminuria was significantly reduced by manidipine (-37.3%; p = 0.003), but not by amlodipine. C-reactive protein was reduced similarly (p < 0.01) by both treatments. Plasma adiponectin was increased (32.9%; p = 0.011) and plasma TNF-alpha was reduced by manidipine (-37.1%; p = 0.019), but neither was significantly changed by amlodipine. The HOMA insulin resistance index was significantly reduced by manidipine (-21.3%; p = 0.007), but not by amlodipine (-8.3%; p = 0.062). Tolerability with manidipine was superior to that with amlodipine (p = 0.04).

CONCLUSION

These data support the added value of manidipine in renal and metabolic protection beyond blood pressure reduction in the treatment of hypertensive patients with metabolic syndrome.

Choice of ACE inhibitor combinations in hypertensive patients with type 2 diabetes: update after recent clinical trials

The diabetes epidemic continues to grow unabated, with a staggering toll in micro- and macrovascular complications, disability, and death. Diabetes causes a two- to fourfold increase in the risk of cardiovascular disease, and represents the first cause of dialysis treatment both in the UK and the US. Concomitant hypertension doubles total mortality and stroke risk, triples the risk of coronary heart disease and significantly hastens the progression of microvascular complications, including diabetic nephropathy. Therefore, blood pressure reduction is of particular importance in preventing cardiovascular and renal outcomes. Successful antihypertensive treatment will often require a combination therapy, either with separate drugs or with fixed-dose combinations. Angiotensin converting enzyme (ACE) inhibitor plus diuretic combination therapy improves blood pressure control, counterbalances renin-angiotensin system activation due to diuretic therapy and reduces the risk of electrolyte alterations, obtaining at the same time synergistic antiproteinuric effects. ACE inhibitor plus calcium channel blocker provides a significant additive effect on blood pressure reduction, may have favorable metabolic effects and synergistically reduce proteinuria and the rate of decline in glomerular filtration rate, as evidenced by the GUARD trial. Finally, the recently published ACCOMPLISH trial showed that an ACE inhibitor/calcium channel blocker combination may be particularly useful in reducing cardiovascular outcomes in high-risk patients. The present review will focus on different ACE inhibitor combinations in the treatment of patients with type 2 diabetes mellitus and hypertension, in the light of recent clinical trials, including GUARD and ACCOMPLISH.

Efficacy of low-dose hydrochlorothiazide in combination with telmisartan on early morning blood pressure in uncontrolled hypertensive patients

Hypertensive patients whose BP was uncontrolled despite the use of antihypertensive agents, including an ARB (candesartan 8 mg/day or valsartan 80 mg/day), were enrolled. The patients were randomly assigned to combination therapy with telmisartan 40 mg/day (changed from current ARB) and hydrochlorothiazide (HCTZ) 12.5 mg/day (T + H, n = 32) or to no change in their current drug regimen (CTL, n = 32). The observation period was 12 weeks. The office and home BPs were significantly reduced in the T + H compared to those in the CTL. A sufficient and long-acting BP lowering effect, as reflected in decreased early morning BP, was obtained with the combination of low-dose HCTZ and telmisartan without apparent metabolic deterioration.

Obesity and hypertension: mechanisms, cardio-renal consequences, and therapeutic approaches

The increasing prevalence of obesity in the industrialized world is causing an alarming epidemic. Almost 70% of American adults are overweight or obese. The link between increasing body weight and hypertension is well established. Obesity hypertension through metabolic, endocrinic, and systemic hemodynamic alteration causes structural vascular and cardiac adaptations that trigger concentric, eccentric left ventricular hypertrophy and electrophysiological changes, which may increase the risk for congestive heart failure and sudden cardiac death as a result of arrhythmias. The increased renal blood flow in conjunction with a decreased renal vascular resistance causes renal hyperperfusion and hyperfiltration. Such changes lead to glomerulomegaly, focal segmental glomerulosclerosis, tubulointerstitial inflammation, and fibrosis that characterize the renal damage in obese hypertensive subjects. We propose that weight reduction, with the addition of other nonpharmacological approaches that included exercise and reduction in alcohol intake, should be the first choice to treat obesity hypertension. Salt restriction may be helpful only in salt-sensitive patients. The benefits of diet in obese patients include improvement of insulin sensitivity, reduction in sympathetic nervous and renin angiotensin system activities, and restoration of leptin sensitivity. As a consequence of these and other metabolic changes, the previously described systemic and renal hemodynamic alterations improved and the cardiovascular and renal morphological changes induced by obesity were lessened. After reviewing the medications available, we believe that owing to the cardiovascular and renal morbidity and mortality that characterized obesity hypertension, the ACEI or ARBs offer the best cardio-renal protection and should be the pharmacologic treatment of choice. If these alone do not control BP adequately, then a low-dose diuretic should be added as a second approach. Although we strongly believe in our proposal, more multicenter long-term clinical pharmacological trials are needed to evaluate the efficacy and safety of the antihypertensive approaches in the treatment of obesity hypertension.

Fixed combination of irbesartan and hydrochlorothiazide in the management of hypertension

Approximately 25% of the adult population worldwide is hypertensive and thus at risk of cardiovascular morbidity and mortality. Despite the availability of many antihypertensive drugs, at least 50% of patients do not achieve blood pressure (BP) targets and thus remain at increased cardiovascular risk. Fixed-dose (FD) irbesartan/hydrochlorothiazide (HCTZ) is an antihypertensive combination therapy approved for the treatment of patients whose BP is not adequately controlled on monotherapy and for initial treatment of patients likely to need multiple drugs to achieve their BP goal. The efficacy and tolerability of FD irbesartan/HCTZ has been demonstrated in both patient populations in large multicenter studies. In patients failing antihypertensive monotherapy, FD irbesartan/HCTZ (150/12.5 mg) has been shown to be more effective than FD valsartan/HCTZ (80/12.5 mg) and at least comparable to FD losartan/HCTZ (50/12.5 mg). In patients with moderate or severe hypertension receiving FD irbesartan/HCTZ as initial therapy, this combination achieved more rapid BP reductions compared with irbesartan monotherapy and enabled a greater proportion of patients with severe hypertension to achieve their BP target. FD irbesartan/HCTZ is thus a valuable addition to the clinician’s armamentarium for the management of hypertension and should help more patients achieve their BP target.

Risk factor assessment for new onset diabetes: literature review

Metabolic syndrome (MS), typified by hypertension, abdominal obesity, dyslipidaemia and impaired glucose metabolism, is a precursor of type 2 diabetes. Thiazide diuretics (TD) and beta-blockers are associated with increased risk of diabetes in patients with hypertension; however, the role of these agents in development of diabetes in MS patients is unknown. We reviewed the literature regarding risk factors for diabetes development and compared this with data from the Study of Trandolapril/Verapamil SR And Insulin Resistance (STAR), which investigated the effects of two fixed-dose combinations (FDCs) [trandolapril/verapamil SR and losartan/hydrochlorothiazide (L/H)] on glucose control and new diabetes in MS patients. In STAR, logistic regression modelling identified haemoglobin A1c [odds ratio (OR) 4.21 per 1% increment; p = 0.003), L/H treatment (OR 4.04; p = 0.002) and 2-h oral glucose tolerance test glucose levels (OR 1.39 per 10 mg/dl increments; p < 0.001) as baseline predictors of diabetes. These data support prior analyses and suggest that choice of antihypertensive agent is important. Patients with MS may be at lower risk of diabetes when using a FDC calcium channel blocker + angiotensin-converting enzyme inhibitor compared with an angiotensin receptor blocker + TD.

Fixed-dose manidipine/delapril versus losartan/hydrochlorothiazide in hypertensive patients with type 2 diabetes and microalbuminuria

INTRODUCTION

Patients with diabetes complicated by hypertension and microalbuminuria have elevated cardiovascular risk, and controlling blood pressure in these patients is an urgent clinical priority. The present study aimed to examine the effects of a fixed-dose combination of antihypertensives on blood pressure and microalbuminuria.

METHODS

Patients with type 2 diabetes, mild-to-moderate hypertension (diastolic blood pressure 85-105 mmHg, systolic blood pressure <160 mmHg, and 24-hour mean systolic blood pressure >130 mmHg), and microalbuminuria were randomized to 1 year of doubleblind treatment with fixed-dose manidipine/delapril (n=54) or losartan/hydrochlorothiazide (HCTZ) (n=56).

RESULTS

Blood pressure was significantly reduced at 1 year in both groups (-22.2/-14.6 mmHg and -19.5/-14.3 mmHg, for systolic and diastolic blood pressure respectively, P<0.001 for each), with no significant between-group difference. Reductions in microalbuminuria occurred in both groups, with mean changes at 1 year of -3.9 mg/mmol creatinine (95% CI -5.3, -2.5) for manidipine/delapril (P<0.001 vs. baseline) and -2.7 mg/mmol creatinine (95% CI -4.0, -1.3) for losartan/HCTZ (P<0.001 vs. baseline and P=0.199 between groups). Glycemia over the 1-year study was largely unaffected; the blood glucose concentration was reduced from baseline with manidipine/delapril, although not statistically significant (mean change -0.2 mmol/L, P=0.064). Both treatments were well tolerated, with discontinuation for adverse events for one (1.9%) patient in the manidipine/delapril group and two (3.6%) in the losartan/HCTZ group.

CONCLUSIONS

A fixed-dose manidipine/delapril combination represents a useful addition to the treatment options available to control hypertension complicated by diabetes and microalbuminuria.

ASH position paper: treatment of hypertension in patients with diabetes-an update

This report updates concepts on hypertension management in patients with diabetes. It focuses on clinical outcomes literature published within the last 3 years and incorporates these observations into modifications of established guidelines. While the fundamentals of treatment and goal blood pressures remain unchanged, approaches to specific patient-related issues has changed. This update focuses on questions such as what to do when a patient has an elevated potassium level when therapy is initiated and whether combinations of agents that block the renin-angiotensin system still be used. In addition, there are updates from trials, just published and in press, that focus on related management issues influencing cardiovascular outcomes in persons with diabetes. Last, an updated algorithm is provided that incorporates many of the new findings and is suggested as a starting point to achieve blood pressure goals.

The metabolic syndrome in hypertension: European society of hypertension position statement

The metabolic syndrome considerably increases the risk of cardiovascular and renal events in hypertension. It has been associated with a wide range of classical and new cardiovascular risk factors as well as with early signs of subclinical cardiovascular and renal damage. Obesity and insulin resistance, beside a constellation of independent factors, which include molecules of hepatic, vascular, and immunologic origin with proinflammatory properties, have been implicated in the pathogenesis. The close relationships among the different components of the syndrome and their associated disturbances make it difficult to understand what the underlying causes and consequences are. At each of these key points, insulin resistance and obesity/proinflammatory molecules, interaction of demographics, lifestyle, genetic factors, and environmental fetal programming results in the final phenotype. High prevalence of end-organ damage and poor prognosis has been demonstrated in a large number of cross-sectional and a few number of prospective studies. The objective of treatment is both to reduce the high risk of a cardiovascular or a renal event and to prevent the much greater chance that metabolic syndrome patients have to develop type 2 diabetes or hypertension. Treatment consists in the opposition to the underlying mechanisms of the metabolic syndrome, adopting lifestyle interventions that effectively reduce visceral obesity with or without the use of drugs that oppose the development of insulin resistance or body weight gain. Treatment of the individual components of the syndrome is also necessary. Concerning blood pressure control, it should be based on lifestyle changes, diet, and physical exercise, which allows for weight reduction and improves muscular blood flow. When antihypertensive drugs are necessary, angiotensin-converting enzyme inhibitors, angiotensin II-AT1 receptor blockers, or even calcium channel blockers are preferable over diuretics and classical beta-blockers in monotherapy, if no compelling indications are present for its use. If a combination of drugs is required, low-dose diuretics can be used. A combination of thiazide diuretics and beta-blockers should be avoided.

Optimizing the treatment of hypertension and stable coronary artery disease: clinical evidence for fixed-combination perindopril/amlodipine

BACKGROUND

Optimized management of hypertension and coronary artery disease (CAD) improves cardiovascular risk and outcomes, and prevents complications. This article reviews evidence for the fixed combination of the angiotensin-converting enzyme (ACE) inhibitor perindopril and the calcium channel blocker amlodipine.

METHODS

A literature search was performed in PubMed/MEDLINE to identify articles published in English between 1988 and March 2008 describing clinical trials, particularly outcome trials, or mechanisms of therapeutic action relevant to the use of combination therapy in patients with hypertension or stable coronary artery disease with an ACE inhibitor (perindopril) and a calcium channel blocker (amlodipine).

FINDINGS

Clinical trials indicate that this combination may have a positive impact on cardiovascular mortality and morbidity in hypertensive individuals. The two complementary mechanisms of action appear to work in synergy, leading to more efficient blood pressure lowering, improved fibrinolytic function, and reduction of secondary effects. This also represents a simplified management strategy for stable CAD. Perindopril has proven efficacy in the prevention of cardiovascular events and mortality in CAD patients, while amlodipine is widely used in the symptomatic management of CAD. Both aspects of guideline-recommended management of CAD are therefore addressed in a single tablet.

CONCLUSIONS

The clinical evidence for fixed-combination perindopril/amlodipine indicates it as a credible option for the optimization of the management of hypertension and CAD.

Hydrochlorothiazide, but not Candesartan, Aggravates Insulin Resistance and Causes Visceral and Hepatic Fat Accumulation

Treatment with angiotensin II receptor blockers is associated with lower risk for the development of type 2 diabetes mellitus compared with thiazide diuretics. The Mechanisms for the Diabetes Preventing Effect of Candesartan Study addressed insulin action and secretion and body fat distribution after treatment with candesartan, hydrochlorothiazide, and placebo. Twenty-six nondiabetic, abdominally obese, hypertensive patients were included in a multicenter 3-way crossover trial, and 22 completers (by predefined criteria; 10 men and 12 women) were included in the analyses. They underwent 12-week treatment periods with candesartan (C; 16 to 32 mg), hydrochlorothiazide (H; 25 to 50 mg), and placebo (P), respectively, and the treatment order was randomly assigned and double blinded. Intravenous glucose tolerance tests and euglycemic hyperinsulinemic (56 mU/m 2 per minute) clamps were performed. Intrahepatic and intramyocellular and extramyocellular lipid content and subcutaneous and visceral abdominal adipose tissue were measured using proton magnetic resonance spectroscopy and MRI. Insulin sensitivity (M-value) was reduced following H versus C and P (6.07±2.05, 6.63±2.04, and 6.90±2.10 mg/kg of body weight per minute, mean±SD; P ≤0.01). Liver fat content was higher ( P <0.05) following H than both P and C. The subcutaneous to visceral abdominal adipose tissue ratio was reduced following H versus C and P ( P <0.01). Glycosylated hemoglobin, alanine aminotransferase, aspartate aminotransferase, and high-sensitivity C-reactive protein levels were higher ( P <0.05) after H, but not C, versus P. There were no changes in body fat, intramyocellular lipid, extramyocellular lipid, or first-phase insulin secretion. Blood pressure was reduced similarly by C and H versus P. In conclusion, visceral fat redistribution, liver fat accumulation, low-grade inflammation, and aggravated insulin resistance were demonstrated after hydrochlorothiazide but not candesartan treatment. These findings can partly explain the diabetogenic potential of thiazides.