The effect of a losartan-based treatment regimen on isolated systolic hypertension

Rice Bran Supplement Containing A Functional Substance, the Novel Peptide Leu-Arg-Ala, has Anti-Hypertensive Effects: A Double-Blind, Randomized, Placebo-Controlled Study

The anti-hypertensive effect of processed rice bran (PRB) was recently reported, for which the novel peptide Leu-Arg-Ala (LRA) was identified as the functional substance. The purpose of this study was to assess the anti-hypertensive effects of a rice bran supplement containing PRB in individuals with high-normal blood pressure (systolic blood pressure (SBP): 130–139 mmHg and/or diastolic blood pressure (DBP): 85–89 mmHg) or grade 1 hypertension (SBP: 140–159 mmHg and/or DBP: 90–99 mmHg). One hundred individuals with high-normal blood pressure or grade 1 hypertension were recruited to participate in this double-blind, randomized, placebo-controlled study. Participants were randomly allocated to the placebo group (n = 50) or the test group (n = 50). Each group took four test tablets (43 μg LRA/day) or four placebo tablets daily. The decrease in blood pressure in the test group compared with the placebo group was the primary outcome. Adverse events were recorded and hematological/urinary parameters measured to determine the safety of the supplement, which was the secondary outcome. In total, 87 participants completed the study. The SBP of the test group at 12 weeks was significantly lower than that of the placebo group (p = 0.0497). No serious adverse events were observed. Daily consumption of a rice bran supplement containing PRB can safely improve mildly elevated blood pressure.

Identifying patients with resistant hypertension and options for clinical management

In addition to the increasing prevalence of hypertension, the number of patients with treatment-resistant hypertension is also rising. It is important to identify these patients in order to improve the treatment outcomes and to screen for potential secondary causes. Clinical characteristics of patients with resistant hypertension include advanced age, male gender, obesity, high salt intake and alcohol consumption. Those with high baseline blood pressure, diabetes, chronic kidney disease or obstructive sleep apnea are also prone to developing resistant hypertension. Physicians should initiate close monitoring and aggressive treatment for those patients, as resistant hypertension is associated with a higher risk of cardiovascular morbidities, regardless of the control of blood pressure. However, treatment of resistant hypertension is currently a great challenge in clinical practice as all of these patients are already taking multiple antihypertensive medications, including the first-line treatments advocated in guidelines. In patients who have been presented multiple drugs, the room for further titration is often limited. Spironolactone has been demonstrated to be effective as an add-on therapy for patients with resistant hypertension. In addition to drug treatment, baroreceptor stimulation therapy and renal sympathetic denervation are promising new approaches in this group of patients. Further studies on the pathogenesis and the treatment of resistant hypertension would help to improve the outcome of this patient subgroup.

Clinic and ambulatory blood pressure lowering effect of aliskiren/amlodipine/hydrochlorothiazide combination in patients with moderate-to-severe hypertension: a randomized active-controlled trial

OBJECTIVES

To evaluate the clinic and ambulatory blood pressure (BP)-lowering efficacy and safety of an aliskiren/amlodipine/hydrochlorothiazide (HCT) triple combination compared with the component dual combinations, in patients with moderate-to-severe hypertension.

METHODS

This 8-week, double-blind, randomized, active-controlled study, after 1-4 weeks single-blind placebo run-in period, randomized 1191 patients to receive once-daily aliskiren/amlodipine 150/5 mg (n = 287), aliskiren/HCT 150/12.5 mg (n = 298), amlodipine/HCT 5/12.5 mg (n = 296), or aliskiren/amlodipine/HCT 150/5/12.5 mg (up-titrated from aliskiren/HCT 150/12.5 mg after initial 3 days) (n = 310) for 4 weeks, followed by forced titration to double the initial dose for the next 4 weeks.

RESULTS

Baseline mean sitting SBP and DBP (msSBP/msDBP) was comparable among treatment groups. The aliskiren/amlodipine/HCT combination resulted in significant least squares mean reduction in msSBP/msDBP from baseline to endpoints (week 4, -30.7/-15.9  mmHg; week 8, -37.9/-20.6  mmHg), superior (P < 0.001) to each of the dual combinations. The triple combination was associated with -27.8  mmHg reduction in msSBP at week 2, significantly better than the dual combinations (P < 0.05). Significantly greater mean SBP/DBP-lowering effect for triple vs. dual combinations was also demonstrated through 24-h, daytime, and night-time ambulatory BP measurements. Significantly greater (P < 0.001) BP control (msSBP/msDBP < 140/90  mmHg) was achieved with triple combination in patients with moderate-to-severe (62.3%) and severe (57.5%) hypertension.

CONCLUSION

Aliskiren/amlodipine/HCT at 150/5/12.5 mg (week 4) and 300/10/25 mg (week 8) provided statistically superior reductions in msSBP/msDBP and greater BP control rates vs. the dual combinations, and was well tolerated. The improved efficacy of BP reduction was evident within 2 weeks of initiating triple therapy even at low dose.

Blood pressure effects of high-dose amlodipine-benazepril combination in Black and White hypertensive patients not controlled on monotherapy

Background

Black hypertensive patients are more resistant to angiotensin-converting enzyme (ACE) inhibitor monotherapy than White patients. This resistance can be overcome with the combination of ACE inhibitors with diuretics or calcium-channel blockers (CCBs).

Objectives

The objective of this clinical investigation was to evaluate the antihypertensive effectiveness of monotherapy with the ACE inhibitor benazepril or the CCB amlodipine and their combination in Black and White hypertensive patients in two separate studies.

Methods

This was a post hoc analysis of data from two separate studies, pooled because of their similarities, to increase the sample size. Outpatient Black and White hypertensive patients were selected for these studies. In study H2303, 201 patients of both sexes and races, whose mean seated diastolic blood pressure (MSDBP) was ≥95 mmHg after 4 weeks of single-blind treatment with benazepril 40mg/day, were randomized into two groups. Group 1 received benazepril 40mg/day and group 2 received amlodipine/benazepril 5/40mg/day, which was uptitrated to amlodipine/benazepril 10/40 mg/day at week 4 of the study. In study H2304, 812 similar patients, whose MSDBP was ≥95 mmHg after 4 weeks of single-blind treatment with amlodipine 10 mg/day, were randomized into three groups. Group 1 received amlodipine/benazepril 10/20 mg/day, uptitrated to amlodipine/benazepril 10/40 mg/day after 2 weeks. Group 2 received amlodipine/benazepril 10/20 mg/day. Group 3 received amlodipine 10 mg/day. All three groups were followed up for 6 additional weeks.

Results

This report presents the results of post hoc analysis of pooled data from two separate but similar studies. Combination therapy resulted in greater lowering of MSDBP and mean seated systolic blood pressure (MSSBP) than monotherapy with either benazepril or amlodipine (p< 0.001). With respect to combination therapy, the combination of amlodipine/benazepril 10/20 mg/day resulted in greater blood pressure (BP) reductions in White patients than in Black patients (p<0.004). In contrast, the combination of amlodipine/benazepril 10/40 mg/day resulted in similar BP reductions in both Black and White hypertensive patients. There were no serious clinical or metabolic side effects noted, with the exception of pedal edema, which was more common with amlodipine monotherapy.

Conclusion

This study showed that combination therapy with amlodipine/benazepril is more effective in BP lowering than monotherapy with the component drugs. Black hypertensive patients are responsive to the combination of amlodipine/benazepril; however, they require higher dose combinations for BP reductions similar to those achieved in White hypertensive patients.

Therapy of hypertension in African Americans

Hypertension in African Americans is a major clinical and public health problem because of the high prevalence and premature onset of elevated blood pressure (BP) as well as the high burden of co-morbid factors that lead to pharmacological treatment resistance (obesity, diabetes mellitus, depressed glomerular filtration rate, and albuminuria). BP control rates are lower in African Americans, especially men, than in other major race/ethnicity-sex groups; overall control rates are 29.9% for non-Hispanic Black men. Optimal antihypertensive treatment requires a comprehensive approach that encompasses multifactorial lifestyle modifications (weight loss, salt and alcohol restriction, and increased physical activity) plus drug therapy. The most important initial step in the evaluation of patients with elevated BP is to appropriately risk stratify them to allow determination of whether they are truly hypertensive and also to determine their goal BP levels. The overwhelming majority of African American hypertensive patients will require combination antihypertensive drug therapy to maintain BP consistently below target levels. The emphasis is now appropriately on utilizing the most effective drug combinations for the control of BP and protection of target-organs in this high-risk population. When BP is >15/10 mmHg above goal levels, combination drug therapy is recommended. The preferred combination is a calcium antagonist/angiotensin-converting enzyme inhibitor or, alternatively, in edematous and/or volume overload states, a thiazide diuretic/angiotensin-converting inhibitor.

Acute vascular effects of the angiotensin II receptor antagonist olmesartan in normal subjects: relation to the renin-aldosterone system

The extent to which the clinical effects of angiotensin receptor blockers (ARB) are related to ambient renin system activity remains poorly defined. Therefore, we measured blood pressure (BP), large (C1) and small (C2) arterial compliance, systemic vascular resistance (SVR), plasma renin activity (PRA), and the 24-h urinary excretion of sodium (UNaV) and aldosterone before and 1, 2, 4, and 24 h after administration of single doses of placebo, and 5, 20, and 40 mg of the ARB olmesartan medoxomil to 12 unmedicated normotensive subjects. In the basal state, SVR was inversely related to UNaV (r=-0,3,p=0,04); the greater the UNaV, the more vasodilated the subject. Indices of arterial compliance, both C1 (r=-0,32,p=0,03) and C2 (r=-0,35,p=0,02) were inversely related to the basal PRA. Renin also predicted olmesartan-induced changes in C1 (r=0,43,p=0,004) and C2r=0,33,p=0,04). The greater the basal PRA, the less the arterial compliance, and the more compliance improved after olmesartan. Both systolic (p=0,003) and diastolic (p<0,0001) BP fell significantly on olmesartan compared with placebo (MANOVA with time), and relations were observed between the basal PRA and olmesartan-induced changes in pressure (systolic BP:r=-0,414,p=0,012; diastolic BP:r=-0.561,p<0,0001) — the greater the initial PRA, the more olmesartan lowered BP. Furthermore, the more pressure fell, the more PRA rose reciprocally (r=-0,44,p=0,007). Finally, aldosterone excretion fell (sig=0,05) on each dose of olmesartan compared with placebo. We conclude that 1) the inverse relation of UNaV and SVR illustrates the reciprocal role of volume versus constrictor factors in maintaining normal BP; and 2) PRA is a physiologic determinant of arterial compliance in normal individuals and of the response to the ARB olmesartan. Measurement of PRA may help to predict clinical ARB responses in individual subjects.

Irbesartan/hydrochlorothiazide for the treatment of isolated systolic hypertension: a subgroup analysis of the INCLUSIVE trial

This post hoc analysis of the Irbesartan/Hydrochlorothiazide (HCTZ) Blood Pressure Reductions in Diverse Patient Populations (INCLUSIVE) trial evaluated the efficacy and safety of fixed-dose irbesartan/HCTZ in patients with isolated systolic hypertension. Adults with uncontrolled systolic blood pressure (SBP) (140-179 mm Hg; 130-179 mm Hg in type 2 diabetes) after 4 weeks or more of antihypertensive monotherapy once-daily treatment with placebo for 4-5 weeks, followed by HCTZ 12.5 mg for 2 weeks, irbesartan/HCTZ 150/12.5 mg for 8 weeks, and then irbesartan/HCTZ 300/25 mg for 8 weeks, in a prospective, multicenter, open-label, single-arm study. In patients with isolated systolic hypertension (n = 443) and the total study population (n = 736), irbesartan/HCTZ treatment for 16 weeks provided comparable mean blood pressure (BP) reductions from baseline (21.4/10.1 mm Hg vs 21.5/10.4 mm Hg; p < .001 vs baseline) and high SBP control rates (74% vs 77%). Patients with isolated systolic hypertension and concomitant type 2 diabetes experienced smaller BP reductions (17.9/8.7 mm Hg vs 22.9/10.7 mm Hg) and lower rates of SBP control (< 130 mm Hg, 47%) than those without diabetes (< 140 mm Hg, 87%). BP reductions from baseline and SBP control rates were similar across isolated systolic hypertension subgroups (> or = 65 vs < 65 years, sex, race, and metabolic syndrome status). Irbesartan/HCTZ was well tolerated, with drug-related adverse events (dizziness, < or = 3%; upper respiratory tract infection, < or = 2%) occurring with similar rates in the isolated systolic hypertension and total population. Fixed-dose irbesartan/HCTZ combination treatment provided effective and well-tolerated BP lowering in a diverse population of patients with isolated systolic hypertension.

Blood pressure lowering efficacy of angiotensin receptor blockers for primary hypertension

BACKGROUND

Angiotensin receptor blockers (ARBs) are widely prescribed for hypertension so it is essential to determine and compare their effects on blood pressure (BP), heart rate and withdrawals due to adverse effects (WDAE).

OBJECTIVES

To quantify the dose-related systolic and/or diastolic BP lowering efficacy of ARBs versus placebo in the treatment of primary hypertension.

SEARCH STRATEGY

We searched CENTRAL (The Cochrane Library 2007, Issue 1), MEDLINE (1966 to February 2007), EMBASE (1988 to February 2007) and reference lists of articles.

SELECTION CRITERIA

Double-blind, randomized, controlled trials evaluating the BP lowering efficacy of fixed-dose monotherapy with an ARB compared with placebo for a duration of 3 to 12 weeks in patients with primary hypertension.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted data. We contacted study authors for additional information. WDAE information was collected from the trials.

MAIN RESULTS

Forty six RCTs evaluated the dose-related trough BP lowering efficacy of 9 ARBs in 13 451 participants with a baseline BP of 156/101 mm Hg. The data do not suggest that any one ARB is better or worse at lowering BP. A dose of 1/8 or 1/4 of the manufacturers' maximum recommended daily dose (Max) achieved a BP lowering effect that was 60 to 70% of the BP lowering effect of Max. A dose of 1/2 Max achieved a BP lowering effect that was 80% of Max. ARB doses above Max did not significantly lower BP more than Max. Due to evidence of publication bias, the largest trials provide the best estimate of the trough BP lowering efficacy for ARBs as a class of drugs: -8 mm Hg for SBP and -5 mm Hg for DBP. ARBs reduced BP measured 1 to 12 hours after the dose by about 12/7 mm Hg.

AUTHORS' CONCLUSIONS

The evidence from this review suggests that there are no clinically meaningful BP lowering differences between available ARBs. The BP lowering effect of ARBs is modest and similar to ACE inhibitors as a class; the magnitude of average trough BP lowering for ARBs at maximum recommended doses and above is -8/-5 mmHg. Furthermore, 60 to 70% of this trough BP lowering effect occurs with recommended starting doses. The review did not provide a good estimate of the incidence of harms associated with ARBs because of the short duration of the trials and the lack of reporting of adverse effects in many of the trials.

Efficacy and safety of fixed combinations of irbesartan/hydrochlorothiazide in older vs younger patients with hypertension uncontrolled with monotherapy

Subgroup analysis of the Irbesartan/Hydrochlorothiazide Blood Pressure Reductions in Diverse Patient Populations (INCLUSIVE) trial evaluated the efficacy and safety of irbesartan/hydrochlorothiazide (HCTZ) fixed combinations in patients aged 65 years or older with uncontrolled systolic blood pressure (SBP) after >or= 4 weeks of antihypertensive monotherapy. The INCLUSIVE trial was a prospective, open-label, single-arm trial carried out in 119 sites. Of 844 patients completing placebo treatment, 212 were aged 65 years or older. Participants received treatment with placebo (4-5 weeks), HCTZ 12.5 mg (2 weeks), irbesartan/HCTZ 150/12.5 mg (8 weeks), and then irbesartan/HCTZ 300/25 mg (8 weeks). From baseline to week 18 (n=184, intent-to-treat population), mean change in SBP was -23.0+/-13.3 mm Hg (P<.001) and diastolic BP (DBP) was -10.9+/-7.7 mm Hg (P<.001). Mean SBP/DBP at study end was 134.0+/-14.7/75.1+/-8.4 mm Hg, and SBP, DBP, and SBP/DBP goal was achieved in 73%, 96%, and 72% of patients, respectively. Irbesartan/HCTZ combination therapy allowed SBP goal attainment in 73% of patients aged 65 years or older whose hypertension was previously uncontrolled with antihypertensive monotherapy.

The treatment of hypertension in the elderly

Following a hypertension symposium in San Francisco in September 2007, an expert panel was convened to discuss the treatment of hypertension in the elderly. Based on recent data, new recommendations may be indicated. The session was moderated by Marvin Moser, MD, Clinical Professor of Medicine at Yale University, New Haven, CT. Participants were William Cushman, MD, Professor of Preventive Medicine and Medicine at the University of Tennessee in Memphis, and Michael Ziegler, MD, Professor of Medicine, University of California at San Diego. The discussion was supported by Novartis Pharmaceuticals and Merck & Company, and each author received an honorarium from Novartis Pharmaceuticals and Merck & Company for time and effort spent participating in the discussion and reviewing the transcript for intellectual content before publication. The authors maintained full control of the discussion and the resulting content of this article.

Risk-based classification of hypertension and the role of combination therapy

The recognition of a continuous relationship between elevated blood pressure (BP) and cardiovascular risk has influenced national and international guidelines for the classification, prevention, and management of hypertension. The most recent report (2003) of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure uses BP thresholds to define categories of normal, prehypertension, and hypertension. A new definition proposed by the Hypertension Writing Group in 2005 offers an approach to diagnosis and management based on global or total risk. Thus, even in the absence of sustained elevations in BP, patients may have a moderate to high risk of vascular events due to the presence of additional cardiovascular risk factors, disease markers, and target organ damage. The 2007 European guidelines continue to classify hypertension based on cutoffs while also placing emphasis on multivariate formulations for cardiovascular risk assessment and goals of therapy. All 3 sets of guidelines acknowledge the necessity of using > or =2 antihypertensive agents to attain BP goals in many patients.

What factors contribute to the inadequate control of elevated blood pressure?

Inadequate control of blood pressure may be attributed to both provider-related and patient-related factors. Health care provider-related factors may include an excessive reliance on monotherapy and reluctance to increase drug doses or add additional antihypertensive agents to the treatment regimen. The primary patient-related factor is nonadherence with the prescribed antihypertensive medication. Although the high cost of therapy is sometimes a reason for poor adherence, drug side effects or dosing considerations may be more important factors. Better adherence with antihypertensive medication is associated with a significantly greater likelihood of achieving blood pressure control and, consequently, with lower costs and reduced utilization of health care resources. Therefore, strategies that improve long-term adherence should be adopted. Single-pill, or fixed-dose, combination therapy is one approach that improves adherence, while also providing the antihypertensive efficacy needed to help patients achieve their blood pressure goals.

Rationale for Combination Therapy in Hypertension Management: Focus on Angiotensin Receptor Blockers and Thiazide Diuretics

Despite recognition that hypertension is a major risk factor for cardiovascular events and mortality, blood pressure control rates remain low in the US population. Reflecting clinical trial results, hypertension management guidelines assert the clinical benefit of achieving current blood pressure goals and indicate that most patients will require 2 or more drugs to reach goal. Well-designed drug combinations counter hypertension via complementary mechanisms that increase antihypertensive efficacy, potentially with lower rates of adverse events than higher dose monotherapy regimens. Lower adverse event rates, in turn, may contribute to greater adherence with treatment. The combination of a low-dose diuretic with agents that block the effects of the renin-angiotensin system (RAS), such as angiotensin receptor blockers, has been found in numerous clinical trials to be highly effective for lowering blood pressure in patients with uncomplicated as well as high-risk hypertension, with a comparable favorable side effect profile compared with monotherapy. Moreover, agents that block the RAS are associated with a lower risk of new-onset diabetes mellitus than other antihypertensive classes. Complementary combinations of antihypertensive agents provide an efficient and effective approach to hypertension management.

Hypertension: trends in prevalence, incidence, and control

Hypertension is the leading cause of cardiovascular disease worldwide. Prior to 1990, population data suggest that hypertension prevalence was decreasing; however, recent data suggest that it is again on the rise. In 1999-2002, 28.6% of the U.S. population had hypertension. Hypertension prevalence has also been increasing in other countries, and an estimated 972 million people in the world are suffering from this problem. Incidence rates of hypertension range between 3% and 18%, depending on the age, gender, ethnicity, and body size of the population studied. Despite advances in hypertension treatment, control rates continue to be suboptimal. Only about one third of all hypertensives are controlled in the United States. Programs that improve hypertension control rates and prevent hypertension are urgently needed.

Angiotensin II antagonists--therapeutic benefits spanning the cardiovascular disease continuum from hypertension to heart failure and diabetic nephropathy

BACKGROUND

The cardiovascular benefits of angiotensin II antagonists (AIIAs) have been evaluated not only in terms of their ability to lower blood pressure but also on their ability to prevent strokes, cardiac events, and target organ damage. This review summarizes the body of evidence-based data demonstrating the efficacy of AIIAs across the spectrum of cardiovascular disease.

METHODS

A PubMed/MEDLINE search of English-language articles (1990 to September 2005) was used to identify articles describing clinical studies, particularly outcome trials, or mechanisms of therapeutic action pertinent to the therapy of cardiovascular disease or nephropathy.

FINDINGS

The antihypertensive efficacy of AIIAs is apparent across a wide spectrum of hypertensive patients, including black and Asian patients and patients with isolated systolic hypertension. More importantly, large outcome-based studies have demonstrated the efficacy of AIIAs across the continuum of cardiovascular disease, including hypertension, heart failure, post-myocardial infarction, and diabetic nephropathy. The Losartan Intervention For Endpoint reduction in hypertension study (LIFE), Reduction of Endpoints in Non-insulin-dependent Diabetes Mellitus with the AII Antagonist Losartan (RENAAL), and the Irbesartan Type 2 Diabetic Nephropathy Trial (IDNT) indicate that AIIAs confer cardiovascular and renal protective effects beyond their ability to lower blood pressure. These bloodpressure independent protective benefits of AIIAs may arise not only by blocking the deleterious effects of AII mediated via the AT1-receptor but may also be due to beneficial molecule-specific effects. As a class, AIIAs are well tolerated with an overall adverse event profile generally comparable to placebo and superior to that typically seen with calcium channel blockers, ACE inhibitors, diuretics, and beta-blockers.

CONCLUSIONS

By utilizing the body of clinical trial evidence as a guide to rational prescribing of AIIAs, practitioners can expect to deliver clinical benefits to their patients in terms of survival, prognosis, and quality of life.

Treatment of systolic hypertension: spotlight on recent studies with angiotensin II antagonists

Systolic blood pressure has a continuous, graded, strong, independent, and aetiologically significant relationship to mortality from coronary heart disease, stroke, and all cardiovascular diseases, as well as to all-cause mortality and life expectancy. Angiotensin II (AII) may be intimately involved in the pathogenesis of systolic hypertension through multiple mechanisms, including decreasing the elastin content and increasing the collagen content of the arterial wall, thickening and fibrotic remodelling of the vascular intima, and proliferating smooth muscle cells in the arterial wall, resulting in increased thickness, stiffening, and partial loss of contractility. AII antagonists may therefore offer hitherto unrecognized benefits (independent of blood pressure) on age-related vascular damage and provide particular benefits in patients with systolic hypertension. Recent evidence has demonstrated that losartan offers cardiovascular outcomes benefits in isolated systolic hypertension (ISH) associated with an excellent tolerability profile. This, in patients with ISH, AII antagonists more facilitate systolic BP control, providing cardiovascular protection and offering an excellent risk-benefit profile.

Angiotensin receptor blockade in the challenging era of systolic hypertension

Systolic blood pressure is a major cardiovascular risk factor which is often associated with arterial stiffness. Markers of arterial stiffness, such as pulse pressure and carotid-femoral pulse wave velocity, have been proved independent predictors of cardiovascular risk. Recent evidence suggests that the renin-angiotensin system is involved in the pathogenesis of systolic hypertension and arterial stiffness. Outcome trials have shown impressive cardiovascular protection by reducing systolic blood pressure (BP) with drug treatment. However, in clinical practice systolic hypertension remains largely uncontrolled, first, because systolic BP goal is more difficult to be reached than diastolic and, second, because physicians are often reluctant to intensify treatment in patients with systolic BP close to 150 mmHg. Recent trials have focused on the effects of antihypertensive drugs not only on blood pressure, but also on pulse pressure and pulse-wave velocity. Blockade of the renin-angiotensin-aldosterone system, using angiotensin-converting enzyme inhibitors and more recently angiotensin receptor blockers, has been shown to provide beneficial effects on arterial stiffness that appear to be independent of their antihypertensive effects. Recent outcome trials have shown significant cardiovascular protection with angiotensin receptor blockers. These drugs have an excellent placebolike profile of adverse effects which is maintained when these drugs are combined with low-dose diuretics. Therefore, an angiotensin receptor blocker-based treatment strategy appears to be an attractive and evidence-based approach for the management of systolic hypertension, the reduction of arterial stiffness and the prevention of cardiovascular disease.

Medication adherence: a key factor in achieving blood pressure control and good clinical outcomes in hypertensive patients

PURPOSE OF REVIEW

Patients' adherence to antihypertensive drug regimens is a complex but important factor in achieving blood pressure control and reducing adverse cardiovascular outcomes. Approximately one half of patients with hypertension adhere to prescribed medications, and fewer than one in three patients have controlled blood pressure.

RECENT FINDINGS

Several recent studies have highlighted the importance of patient medication adherence and have outlined factors that affect patient compliance with prescribed therapy.

SUMMARY

On the basis of published studies, a conceptual framework of factors that affect patient adherence is presented. Recognizing patient nonadherence to medical therapy as a factor leading to poor blood pressure control and adverse outcomes remains a key challenge for clinicians caring for patients with hypertension.

Comparison of the blood pressure-lowering effects and tolerability of Losartan- and Amlodipine-based regimens in patients with isolated systolic hypertension

BACKGROUND

Elevated systolic blood pressure is a more important risk factor for cardiovascular and renal disease than elevated diastolic blood pressure. Isolated systolic hypertension (ISH) is the predominant form of hypertension in the elderly. Effects of angiotensin II on the vascular wall and endothelium may contribute to development of ISH.

OBJECTIVE

The primary objective of this study was to compare the effects on trough sitting systolic blood pressure (SiSBP) of a regimen of losartan, a selective angiotensin II-receptor antagonist, and an amlodipine-based regimen in patients with ISH.

METHODS

This multicenter, prospective, randomized, double-blind, parallel-group study consisted of a 4-week placebo phase and an 18-week active-treatment phase. The losartan-based regimen consisted of losartan 50 mg, increased as needed to losartan 50 mg/hydrochlorothiazide (HCTZ) 12.5 mg at week 6 and to losartan 100 mg/HCTZ 25 mg at week 12 to achieve a target SiSBP <140 mm Hg. the amlodipine-based regimen consisted of amlodipine 5 mg, increased as needed to amlodipine 10 mg at week 6 and to amlodipine 10 mg/HCTZ 25 mg at week 12. The primary efficacy measure was change in trough SiSBP from baseline to week 18. Information on the tolerability of study treatments was collected at each visit, including the investigator's and patient's observations of clinical adverse experiences (CAEs), laboratory adverse experiences, and responses to a symptom questionnaire.

RESULTS

Eight hundred fifty-seven patients (65.6% female) were randomized to treatment, 432 in the losartan group and 425 in the amlodipine group. Their mean age was 67.6 years, and they had a mean duration of hypertension of 6.7 years at baseline. The losartan and amlodipine groups (intent-to-treat population) had baseline mean SiSBP values of 171.2 and 171.9 mm Hg, respectively. At week 18 (the primary end point), the mean change from baseline in SiSBP was -27.4 mm Hg for 426 patients who received losartan and -28.1 mm Hg for 419 patients who received amlodipine (estimated least-square mean difference, 0.3 mm Hg; 95% CI, -1.4 to 2.0), indicating that losartan's effect on systolic blood pressure was noninferior to that of amlodipine. The proportion of patients who responded (SiSBP <140 mm Hg or a > or =20-mm Hg decrease in SiSBP from baseline) was comparable between groups (73.9% losartan, 75.4% amlodipine). The incidence of CAEs and drug-related CAEs was significantly greater in the amlodipine group (amlodipine, 79.8% and 43.8%, respectively; losartan, 67.8% and 25.5%; P < or = 0.001). In addition, more patients in the amlodipine group discontinued therapy due to a drug-related CAE compared with patients in the losartan group (12.9% vs 4.4%, respectively; P < or = 0.001). Lower-extremity edema was the most common drug-related CAE in the amlodipine group (24.0% amlodipine, 2.5% losartan; P < or = 0.001); dizziness was the most common drug-related CAE in the losartan group (6.0% losartan, 4.0% amlodipine).

CONCLUSIONS

In these patients with ISH, losartan and amlodipine produced comparable clinically relevant reductions in SiSBP; however, losartan was better tolerated, as evidenced by fewer CAEs and discontinuations compared with amlodipine. Losartan may be considered for the initial treatment of ISH.

A multicenter, randomized, double-blind, placebo-controlled, 8-week trial of the efficacy and tolerability of once-daily losartan 100 mg/hydrochlorothiazide 25 mg and losartan 50 mg/hydrochlorothiazide 12.5 mg in the treatment of moderate-to-severe essential hypertension

BACKGROUND

Many patients with moderate-to-severe hypertension require multiple drug therapy to achieve blood-pressure goals. Fixed-dose combination therapy with losartan and hydrochlorothiazide may be useful in this population.

OBJECTIVE

This study was conducted to obtain additional data on the antihypertensive efficacy and tolerability of once-daily, fixed-dose combinations of losartan and hydrochlorothiazide.

METHODS

This was a multicenter, randomized, double-blind, parallel-group, placebo-controlled trial. Patients > or = 21 years of age with moderate-to-severe essential hypertension, defined as a mean trough sitting diastolic blood pressure (SiDBP) of 105 to 115 mm Hg, were randomly assigned in a 2:2:1 ratio to receive losartan 100 mg/hydrochlorothiazide 25 mg (L100/25), losartan 50 mg/hydrochlorothiazide 12.5 mg (L50/12.5), or placebo (PBO) once daily for 8 weeks. The primary efficacy measurement was the mean change from baseline in trough SiDBP in the L100/25 versus L50/12.5 treatment groups. Responders were defined as patients with mean trough SiDBP <90 mm Hg or a > or = 10-mm Hg decrease in mean trough SiDBP.

RESULTS

A total of 446 patients were randomly assigned to receive L100/25 (n = 173), L50/12.5 (n = 184), or PBO (n = 89). At week 8, mean trough SiDBP was significantly lower than at baseline in the L100/25 (-17.5 mm Hg), L50/12.5 (-15.2 mm Hg), and PBO groups (-8.5 mm Hg) (all P < 0.001). The difference between the active-treatment groups was statistically significant (-2.2 mm Hg; 95% Cl, range -3.8 to -0.6) (P = 0.006), as was the difference between the L100/25 and PBO groups (-9.0 mm Hg; 95% CI, range -I1.0 to -7.0) (P < 0.001) and the L50/12.5 and PBO groups (-6.7 mm Hg; 95% CI, range -8.7 to -4.8) (P < 0.001). At week 8, the percentages of responders were 86.7% (144 of 166), 78.9% (142 of 180), and 50.0% (42 of 84) in the L100/25, L50/12.5, and PBO groups, respectively. The incidence of adverse experiences (AEs) was 34.7% (60 of 173) in the L100/25 group, 23.9% (44 of 184) in the L50/12.5 group, and 32.6% (29 of 89) in the PBO group. The incidence of drug-related AEs was similar among the treatment groups (L100/25, 7.5% [13 of 173]; L50/12.5, 7.1% [13 of 184]; and PBO, 11.2% [10 of 89]).

CONCLUSIONS

This study demonstrates the antihypertensive efficacy and tolerability of the once-daily, fixed-dose combination L50/12.5 in patients with moderate-to-severe essential hypertension. In this study, L100/25 provided additional anti-hypertensive efficacy beyond that of L50/12.5 (and both were more efficacious than PBO). Approximately 4 of 5 patients (78.9%) treated with L50/12.5 responded to therapy, as did nearly 9 of 10 patients (86.7%) treated with L100/25. The tolerability profiles of L50/12.5 and L100/25 were similar to that of PBO.