Is fixed combination therapy appropriate for initial hypertension treatment?

Antihypertensive agent utilization patterns among patients with uncontrolled hypertension in the United States

Hypertension affects approximately one-third of the US adults. This study investigated antihypertensive utilization patterns among hypertensive patients who were prescribed treatment, yet still experienced uncontrolled hypertension. Data from the Decision Resources Group Real World Evidence Data Repository US database (2015-2016) were used to construct a cohort of uncontrolled hypertension patients to observe antihypertensive utilization patterns. Results for 5059 patients, with an average age of 57.8 (SD = 13.7), who had, on average 2.4 agents prescribed. Approximately half (51.9%) were female, and most were White (86.8%). More than one-third (N = 1877; 37.1%) of patients were diagnosed with diabetes mellitus (DM) or chronic kidney disease (CKD) that could independently contribute to increased cardiovascular complications. Overall, the most common treatments prescribed, as percent of agents and as percent of patients, respectively, were diuretics (24.9%; 59.6%), followed by angiotensin-converting enzyme inhibitors (ACEIs) (23.8%; 56.9%), beta-blockers (BBs) (18.7%; 44.8%), calcium channel blockers (CCBs) (15.4%; 36.8%), and angiotensin II receptor blockers (ARBs) (13.5%; 32.3%). Approximately one-tenth (10.5%) of the prescriptions were written for fixed-dose combination therapies. Among patients diagnosed with DM and CKD (N = 200), the order of the most common agents was the same as the overall cohort. Only 5.6% of prescriptions written for these patients were fixed-dose combination therapy. Based on clinical guidelines, which suggest using ACEIs, ARBs, or CCBs as first-line therapy, and fixed-dose combination therapy to increase adherence, this indicates over-prescribing of BBs and under-prescribing of fixed-dose combination therapy. These findings illustrate the need to further investigate challenges faced by patients and providers in treatment decision-making.

A multicenter, randomized, and double-blind phase IV clinical trial to compare the efficacy and safety of fixed-dose combinations of amlodipine orotate/valsartan 5/160 mg versus valsartan/hydrochlorothiazide 160/12.5 mg in patients with essential hypertension uncontrolled by valsartan 160 mg monotherapy

BACKGROUND

To determine whether the effectiveness and safety of fixed-dose combinations (FDCs) of amlodipine orotate/valsartan (AML/VAL) 5/160 mg are noninferior to those of valsartan/hydrochlorothiazide (VAL/HCTZ) 160/12.5 mg in hypertensive patients with inadequate response to valsartan 160 mg monotherapy.

METHODS

This 8-week, active-controlled, parallel-group, fixed-dose, multicenter, double-blind randomized controlled, and noninferiority trial was conducted at 17 cardiovascular centers in the Republic of Korea. Eligible patients had mean sitting diastolic blood pressure (msDBP) ≥90 mm Hg despite monotherapy with valsartan 160 mg for 4 weeks. Patients were randomly assigned to treatment with AML/VAL 5/160 mg FDC (AML/VAL) group or VAL/HCTZ 160/12.5 mg FDC (VAL/HCTZ) group once daily for 8 weeks. A total of 238 patients were enrolled (AML/VAL group, n = 121; VAL/HCTZ group, n = 117), of whom 228 completed the study.

RESULTS

At 8 weeks after randomization, msDBP was significantly decreased in both groups (-9.44 ± 0.69 mm Hg in the AML/VAL group and -7.47 ± 0.71 mm Hg in the VAL/HCTZ group, both P < .001 vs baseline). Between group difference was -1.96 ± 1.00 mm Hg, indicating that AML/VAL 5/160 mg FDC was not inferior to VAL/HCTZ 160/12.5 mg FDC at primary efficacy endpoint. Control rate of BP defined as the percentage of patients achieving mean sitting SBP (msSBP) <140 mm Hg or msDBP <90 mm Hg (target BP) from baseline to week 8 was significantly higher in the AML/VAL group than that in the VAL/HCTZ group (84.3% [n = 102] in the AML/VAL group vs 71.3% [n = 82] in the VAL/HCTZ group, P = .016). At 8 weeks after randomization, mean uric acid level was significantly increased in the VAL/HCTZ group compared to that at baseline (0.64 ± 0.08 mg/dL; P < .001). However, it was slightly decreased from baseline in the AML/VAL group (-0.12 ± 0.08 mg/dL; P = .085). The intergroup difference was significant (P < .001).

CONCLUSION

The effectiveness and safety AML/VAL 5/160 mg FDC are noninferior to those of VAL/HCTZ 160/12.5 mg FDC in patients with hypertension inadequately controlled by valsartan 160 mg monotherapy.

Effect of Diuretic or Calcium-Channel Blocker Plus Angiotensin-Receptor Blocker on Diastolic Function in Hypertensive Patients

BACKGROUND

Hypertension increases the risk of left ventricular (LV) diastolic dysfunction, and anti-hypertensive therapy may improve LV relaxation. The aim of this study was to investigate whether combining an angiotensin-receptor blocker (ARB) with either hydrochlorothiazide (HCTZ) or a calcium-channel blocker (CCB) improves LV relaxation in patients with hypertension and diastolic dysfunction.

METHODS AND RESULTS

Hypertensive patients who had not achieved their target blood pressure with at least 4 weeks of ARB therapy were randomly assigned to receive either a fixed-dose combination of losartan and HCTZ (losartan/HCTZ; n=110) or a combination of amlodipine and a typical ARB dosage (CCB/ARB; n=121) and followed for 24 weeks. The primary endpoint was change in early diastolic mitral annular velocity (e', cm/s). Systolic blood pressure decreased in both groups after switch to the combination therapies. E' velocity increased both in the losartan/HCTZ (0.52 cm/s) and in the CCB/ARB (0.59 cm/s) groups. The mean (95% CI) treatment difference was -0.02 (-0.37 to 0.34) cm/s, indicating that improvement in LV relaxation was similar between the groups. The ratio of early mitral inflow velocity to e' velocity and left atrial volume index were significantly decreased in the losartan/HCTZ group.

CONCLUSIONS

The combination of losartan and HCTZ is as effective as amlodipine plus ARB in improving LV relaxation in hypertensive patients.

Prevalence of resistant hypertension and associated factors in Japanese subjects with type 2 diabetes

OBJECTIVE

The prevalence of treatment resistant hypertension (RH) depends on methods used for blood pressure (BP) measurements, goals of BP, and therapeutic efforts in terms of medication and adherence. We focused on diabetic subjects and explored the prevalence of RH in primary care practice.

METHODS

In 1737 subjects with type 2 diabetes who continued regular visits, office BP was evaluated by multiple measurements over one year. RH was defined as using more than four antihypertensive drugs or failure to achieve the goal with three antihypertensive drugs from different classes. The RH prevalence was investigated with BP goals <130/80 and 140/90 mmHg.

RESULTS

The percentage of subjects who achieved BP goals <130/80 and 140/90 were 70.5% and 93.8% with adherence to medication ≥95%, and the corresponding prevalence rates of RH in treated subjects were 28.4% and 21.8%, respectively. Factors independently associated with RH were age (odds ratio 1.02 [95% CI 1.01-1.04]), body mass index (1.10 [1.06-1.13]), variability in systolic BP (1.06 [1.02-1.09]), triglycerides (2.86 [1.34-6.11]), macroalbuminuria (3.33 [2.03-5.48]), estimated glomerular filtration rate (0.98 [0.97-0.99]), retinopathy (1.91 [1.39-2.61]), and family history of hypertension (1.85 [1.23-2.21]). Worsening albuminuria and glomerular filtration rate enhanced the prevalence of RH in a graded manner.

CONCLUSION

Careful estimation of office BP values over one year with a high achievement of BP goals and adequate adherence revealed that the prevalence of RH in type 2 diabetes is high. RH was characterized by accumulation of cardiovascular genetic and environmental risks.

Use of combination antihypertensive therapy initiation in older Americans without prevalent cardiovascular disease

OBJECTIVES

To describe new users of antihypertensive medications and identify predictors of combination therapy initiation in older Americans.

DESIGN

Retrospective observational cohort study.

SETTING

Population-based study using U.S. Medicare fee-for-service healthcare claims (2007-2010).

PARTICIPANTS

Medicare beneficiaries aged 65 and older with no recent diagnoses, procedures, or medications for cardiovascular disease who newly initiated an antihypertensive therapy (n = 275,493; 210,605 initiated monotherapy, 64,888 initiated combination therapy).

MEASUREMENTS

Multivariable Poisson regression was used to assess factors associated with initiation of combination therapy versus monotherapy, including participant characteristics, prescriber characteristics, and participant encounters with the healthcare system.

RESULTS

Initiation of combination therapy increased from 21.9% in 2007 to 24.7% in 2010. The most frequently initiated combinations were angiotensin-converting enzyme inhibitors with thiazide (29.7%) and angiotensin II receptor antagonists with thiazide (18.7%). Blacks (prevalence ratio (PR) = 1.48, 95% confidence interval (CI) = 1.45-1.51 vs. whites), individuals seeing a generalist (PR = 1.10, 95% CI = 1.07-1.14), individuals seeing more than one doctor (PR = 3.38, 95% CI = 3.33-3.44), and participants with no pharmacy claims in the previous 6 months (PR = 1.34, 95% CI = 1.30-1.37 vs. ≥3 unique drug classes) were more likely to initiate combination therapy, whereas those who had more outpatient visits in the previous 12 months were less likely to initiate combination therapy (per five visits, PR = 0.82, 95% CI = 0.80-0.83).

CONCLUSION

Nearly one in four new users of antihypertensive medications aged 65 and older started treatment with combination therapy. Blacks, individuals living in the south, and those with fewer outpatient physician office visits were more likely to initiate combination therapy. Further research is needed to determine whether this approach to managing hypertension is being well targeted to individuals who will require combination treatment.

Efficacy and effects on lipid metabolism of combination treatment with losartan + hydrochlorothiazide versus losartan + amlodipine: a 48-week prospective, multicenter, randomized, open-label trial

BACKGROUND

Both combination therapies of an angiotensin II receptor blocker (ARB) with the thiazide diuretic hydrochlorothiazide (HCTZ) and an ARB with a calcium channel blocker (CCB) are recommended to achieve blood pressure (BP) goals in antihypertensive treatment. However, although HCTZ is known to have unfavorable effects on lipid metabolism, the effects of HCTZ in the ARB + HCTZ combination on lipid metabolism have not been fully elucidated.

OBJECTIVE

The aim of this study was to compare the effects on lipid metabolism of combination treatment with the ARB losartan + HCTZ and losartan + the CCB amlodipine and to assess the efficacy in BP lowering of these 2 combination therapies. The metabolism of glucose, uric acid (UA), and high-sensitivity C-reactive protein (hs-CRP), an inflammation marker of atherosclerosis, were also assessed in association with lipid metabolism.

METHODS

This 48-week, prospective, randomized, open-label trial was conducted at 2 clinics and 2 hospitals in Tokorozawa City (Saitama, Japan) and Shinjuku-ku Ward (Tokyo, Japan). Eligible patients had a systolic BP (SBP) >140 mm Hg and/or diastolic BP (DBP) >90 mm Hg despite a >1-month history of monotherapy with an ARB. Patients were randomly assigned to receive losartan 50 mg/d + HCTZ 12.5 mg/d (LOS + HCTZ) or losartan 50 mg/d + amlodipine 5 mg/d (LOS + CCB) for 48 weeks. Follow-up visits were scheduled at 4, 8, 12, 24, and 48 weeks. Biochemical measurements were centrally measured at a single institute. Tolerability and treatment compliance were assessed by physicians every 4 weeks.

RESULTS

A total of 112 patients were enrolled; 26 were excluded from the final analysis, leaving 42 and 44 patients in the LOS + HCTZ and LOS + CCB groups, respectively, included in the final analysis. At 48 weeks, SBP and DBP were significantly decreased in the 2 treatment groups (both, P < 0.0001). The decrease in SBP was significantly greater in the LOS + HCTZ group than in the LOS + CCB group (P < 0.001). The difference in the decrease in DBP between the 2 groups was nonsignificant. There were no significant differences in the changes from baseline (Δ) in any of the lipid parameters between the 2 groups. The decreases at 8 and 12 weeks in LDL-C, TC, and apolipoprotein (apo) B were significantly greater in the LOS + CCB group compared with those in the LOS + HCTZ group. The between-group differences in ΔTG, ΔHDL-C, ΔapoA-1, and ΔapoE throughout the study were nonsignificant. Changes in fasting plasma glucose (FPG), hemoglobin A1c, and hs-CRP were not significantly different between the 2 groups. The between-group difference in ΔUA in men was not significant, but a significant difference was found in women (LOS + HCTZ, 0.74 mg/dL; LOS + CCB, 0.28 mg/dL [P = 0.0017]). No clinically significant adverse events were reported with either treatment throughout the study.

CONCLUSIONS

The findings from the present study suggest that LOS + HCTZ was more efficacious in decreasing SBP than was LOS + CCB in the management of hypertension refractory to ARB monotherapy. Unfavorable effects on lipid metabolism were not observed with either combination therapy.

Efficacy and safety of linagliptin 2.5 mg twice daily versus 5 mg once daily in patients with type 2 diabetes inadequately controlled on metformin: a randomised, double-blind, placebo-controlled trial

OBJECTIVE

Glycaemic control in patients with type 2 diabetes (T2DM) is often not achieved or not sustained using monotherapy such as metformin, necessitating the addition of other antihyperglycaemic agents. Linagliptin, a dipeptidyl peptidase-4 inhibitor, is licensed for 5 mg once-daily dosing. As metformin is administered twice daily, a fixed-dose combination of these compounds would require twice-daily administration of linagliptin. This study evaluated whether 2.5 mg twice-daily dosing of linagliptin has comparable efficacy and safety to 5 mg once-daily dosing when given in addition to metformin twice daily in patients with inadequate glycaemic control.

METHODS

A total of 491 T2DM patients with glycated haemoglobin (HbA1c) 7.0-10.0% were randomised (5:5:1) to double-blind treatment with linagliptin 2.5 mg twice daily, 5 mg once daily or placebo, respectively, in addition to continuing metformin twice daily (≥1500 mg/day or maximally tolerated dose). The primary endpoint was change from baseline in HbA1c after 12 weeks. ClinicalTrials.gov, NCT01012037.

RESULTS

Mean baseline HbA1c for all patients was 7.97%. After 12 weeks, linagliptin 2.5 mg twice daily and 5 mg once daily both significantly reduced HbA1c (placebo-adjusted changes from baseline -0.74% (95% CI -0.97, -0.52) and -0.80% (95% CI -1.02, -0.58), respectively, both p<0.0001). The treatment difference (twice daily-once daily) between the linagliptin regimens was 0.06 (95% CI -0.07, 0.19), the upper bound of which was less than the predefined noninferiority margin (0.35%). The overall incidence of adverse events with linagliptin 2.5 mg twice daily, 5 mg once daily and placebo was 43.0%, 34.8%, and 38.6% respectively. Hypoglycaemia was rare (3.1% with linagliptin 2.5 mg twice daily, 0.9% with 5 mg once daily, 2.3% with placebo) with no severe episodes. Study limitations include duration, patient population (mainly white) and absence of postprandial glucose data.

CONCLUSIONS

Linagliptin 2.5 mg twice daily had non-inferior HbA1c-lowering effects after 12 weeks compared to 5 mg once daily, with comparable safety and tolerability, in T2DM patients inadequately controlled with metformin.

Revelation on the potency of α(1) -blockers - parallel blockade of angiotensin II receptor: a new finding

CONTEXT

The problem of hypertension has gained enormous proportions in the past decade. Multifactorial etiology and complex pathophysiology of the disease has rendered the treatment of the disease a hard task. Sympathetic nervous system and the renin-angiotensin-aldosterone system are primary contributors of blood pressure homeostasis.

OBJECTIVE

Structural similarities were identified among AT(1) and α(1)-antagonists, initiating a speculation that α(1)-antagonists could possibly block the AT(1) receptor and vice-versa.

METHODS

To corroborate this speculation, we screened prototypical α(1)-antagonists such as prazosin, doxazosin, and terazosin for antagonism of angiotensin II on rat aortic strips. We also examined the AT(1) antagonists losartan, valsartan, and olmesartan for their possible antagonistic effect, on contractions of rat aortic strips induced by phenylephrine.

RESULTS

To our astonishment, we found that prazosin and its analogs which have been reported to have α(1)-antagonistic activity only, were able to shift concentration response curves of angiotensin II.

CONCLUSION

Our findings suggest that the potent antihypertensive effect of prazosin-type α(1)-antagonists is not purely due to α(1)-receptor blocking activity of these compounds but also due to blockade of AT(1) receptors. This finding may lead to the development of more potent dual inhibitors which would prove to be of immense value in the control of the scourge of hypertension.

The therapeutic importance of home blood pressure assessment and combination antihypertensive therapy for achieving target blood pressure control: Ibaraki hypertension assessment trial

Tight blood pressure (BP) control is important for the prevention of cardiovascular disease in hypertensive patients. A cross-sectional study of 2339 patients from 101 clinics and hospitals in Ibaraki Prefecture was performed to evaluate BP control with the patients' current antihypertensive medication. Group A (n=892) included high-risk hypertensive patients with at least one of the following risk factors: diabetes mellitus, chronic kidney disease or a history of myocardial infarction. Group B (n=586) included patients <65 years old and Group C (n=859) included patients ≥65 years old. Both groups B and C included hypertensive patients without the above risk factors. A mean of 1.8±1.0 antihypertensive drugs per patient were prescribed. A total of 35.8% of all patients received monotherapy, 40% received a combination of three therapies and 20.3% received more than three kinds of drugs. The percentage of patients achieving the target BP at the office and at home was significantly higher in Group C than in the other groups (P<0.001). A combination of more than two antihypertensive drugs, including a high dose of either an angiotensin receptor blocker or a calcium channel blocker, was frequently prescribed to Group A to achieve the target office BP. Although the target BP should be lower in Group A (given their comorbidities), the absolute BP value and the number of medications were similar to the other groups. In conclusion, we demonstrated that physicians should treat hypertension more intensively with a combination of more than two antihypertensive drugs, using a high dose to achieve the target BP. In addition, it is important to teach hypertensive patients the clinical importance of monitoring their BP at home and the need to achieve home BP targets.

Combinations of inhibitors of the renin-angiotensin system with calcium channel blockers for the treatment of hypertension: focus on perindopril/amlodipine

BACKGROUND

Combination antihypertensive therapy with an inhibitor of the renin-angiotensin system (RAS) and a calcium channel blocker (CCB) is a rational approach to achieve blood pressure (BP) goals in patients with hypertension, and may provide additional cardiovascular protection compared to other strategies in special populations. This article reviews the rationale for, and evidence supporting, the use of newer fixed-dose combinations of RAS inhibitors and CCBs, with particular emphasis on perindopril/amlodipine.

METHODS

A literature search was performed in Medline and EMBASE databases to identify articles published up to May 2010 describing the impact of combination treatment with angiotensin receptor blocker (ARB)/CCB or angiotensin-converting enzyme (ACE) inhibitor/CCB based antihypertensive strategies on BP or clinical outcomes.

FINDINGS

A substantial body of evidence supports the BP-lowering efficacy of RAS inhibitor/CCB combination therapy in patients with hypertension. RAS inhibitors and CCBs represent two different and complementary mechanisms of actions; their use in combination is associated with effective BP lowering with favourable tolerability and fewer adverse metabolic effects than some other combination therapies. Currently, intervention studies demonstrating the impact of ARB/CCB combinations on cardiovascular mortality and morbidity are lacking. However, evidence from large outcome trials supports the use of ACE inhibitor/CCB combinations for reducing the risk of cardiovascular and renal events, particularly in high-risk patients. There is also evidence that the benefits of ACE inhibitor/CCB combinations may extend beyond those solely associated with brachial BP lowering, by an additional impact on central BP haemodynamics.

CONCLUSIONS

RAS inhibitor/CCB combination therapy is an effective antihypertensive therapy. Strong evidence supports the antihypertensive efficacy of ACE inhibitor/CCB combinations with cardioprotective and renoprotective properties. In particular, evidence suggests that fixed-dose perindopril/amlodipine effectively decreases BP and currently is the only RAS inhibitor/CCB combination proven to decrease all-cause and cardiovascular mortality as well as major cardiovascular events, and thus is a valuable option for the management of hypertension, especially in high-risk patients.

Combination therapy with amlodipine/valsartan in essential hypertension: a 52-week, randomised, open-label, extension study

BACKGROUND

A majority of hypertensive patients require > or = 2 agents to achieve target blood pressure (BP).

METHODS

This 52-week, multicentre, open-label, randomised extension trial to a previously reported double-blind, placebo-controlled study evaluated the safety and efficacy of amlodipine/valsartan (Aml/Val) combination. Patients who successfully completed the core study without serious drug-related adverse events (AEs) and mean sitting systolic BP (MSSBP)/mean sitting diastolic BP (MSDBP) < or = 150/95 mmHg were eligible to enter the extension and be treated with Aml/Val 2.5/80 or 5/80 mg. After 4 weeks of treatment, patients underwent force-titration to receive 5/160 mg (low dose) or 10/160 mg (high dose) for 48 weeks. Addition of hydrochlorothiazide (HCTZ) 12.5 mg was permitted if BP was > or = 140/90 mmHg at Week 8 or later. Patients could be down-titrated to the prior lower combination dose with or without HCTZ if an intolerable AE occurred. Safety evaluations included monitoring of AEs. Efficacy variables were change from baseline in MSDBP (primary) and MSSBP (secondary).

RESULTS

Of 1246 patients randomised, 1075 (86.3%) completed the extension study. At week 52 end-point, change in MSSBP/MSDBP from core study baseline was -22.1/-17.2 mmHg for low-dose regimen and -22.8/-18.1 mmHg for high-dose regimen. For both regimens, reductions in BP were sustained over 52 weeks and mean BP maintained below approximately 135/85 mmHg at all visits. Frequent AEs in the low- and high-dose regimens were peripheral oedema (9.7% and 17.1% respectively), nasopharyngitis (8.1% and 7.2%), and dizziness (5.2% and 7.0%). Incidence of serious AEs was 3.7% with low dose and 4.1% with high dose.

CONCLUSION

The combination of Aml/Val with the optional addition of HCTZ produced clinically significant and persistent reductions in BP over 52 weeks with a favourable tolerability profile.

Efficacy and safety of a single-pill combination of amlodipine/valsartan in Asian hypertensive patients inadequately controlled with amlodipine monotherapy

OBJECTIVE

The antihypertensive efficacy of amlodipine/valsartan combination has not been evaluated in Asian patients as previous large-scale studies enrolled very few patients. This multicentre, randomised, double-blind study assessed the efficacy and safety of a single-pill combination of amlodipine/valsartan versus amlodipine in Asian hypertensive patients.

METHODS

After a 1-4-week washout period, patients (mean sitting diastolic BP [msDBP]: >or=95-<110 mmHg) were treated with amlodipine 5 mg for 4 weeks. Patients inadequately controlled on amlodipine (msDBP >or=90 and <110 mmHg) were randomised to receive amlodipine/valsartan 5/80 mg (n = 349) or amlodipine 5 mg (n = 349) for 8 weeks. Efficacy variables were change in msDBP, mean sitting systolic BP (msSBP) from baseline (at randomisation) to week 8 endpoint, and BP control rate (<140/90 mmHg) at week 8 endpoint. Safety assessments included monitoring and recording of adverse events (AEs).

RESULTS

Baseline characteristics were comparable between the groups. Most patients were Chinese (86.4%), men (65.1%), with a baseline BP 139.5/94.5 mmHg. At week 8 endpoint, the least square mean reduction in BP was significantly greater with amlodipine/valsartan combination than amlodipine monotherapy (-11.4/-9.7 vs. -7.4/-7.1 mmHg; p < 0.0001) with a higher BP control rate (69.2 vs. 57.6%; p = 0.0013). Ambulatory BP monitoring in a subgroup of patients (n = 82), showed a significant 24-h mean BP reduction from baseline with amlodipine/valsartan (-7.3/-6.3 mmHg; p < 0.0001), whereas the reduction was not significant with amlodipine (-0.2/+0.3 mmHg; p > 0.05). The overall incidence of AEs was similar in both groups. Peripheral oedema occurred only in the amlodipine group n = 4 (1.1%) and not in the amlodipine/valsartan combination. Hypotension was reported in only one patient in the amlodipine/valsartan combination. Six patients (0.9%) experienced serious AEs, of which only one SAE, i.e. gastric ulcer, was reported to be related to amlodipine treatment.

CONCLUSION

The single-pill combination of amlodipine/valsartan was efficacious and well-tolerated in Asian hypertensive patients who were inadequately controlled on amlodipine alone. As with all clinical trials, the entry criteria may limit the extrapolation of these results to a broader population. ClinicalTrials.gov Identifier: NCT00413049.

Clinical experience in treating hypertension with fixed-dose combination therapy: angiotensin II receptor blocker losartan plus hydrochlorothiazide

The goal of antihypertensive treatment is to reduce cardiovascular and cerebrovascular events associated with high blood pressure. A combination therapy with different antihypertensive agents is more successful than monotherapy in most hypertensive patients, with the added advantage of a better safety profile. Therefore, treatment of hypertensive patients with fixed-dose combination therapy consisting of the angiotensin II receptor blocker losartan along with hydrochlorothiazide (HCTZ) has several potential benefits over monotherapy with each individual component. It provides more effective blood pressure control, a reduction in the likelihood of adverse effects and facilitation of patient compliance due to a simple once-daily regimen. One of the advantages of the combination of losartan with HCTZ is the potential reduction in HCTZ-induced metabolic disorders; in particular, this combination can have attractive benefits for patients of hyperuricemia. Losartan plus HCTZ fixed-dose combination therapy is frequently recommended for the treatment of hypertension and lowers blood pressure in mild-to-moderate and even severe hypertensive patients to a level comparable with other classes of antihypertensive agents in combination with HCTZ. Fixed-dose combination therapy with losartan plus HCTZ is a logical choice as antihypertensive therapy for patients in whom combination therapy is necessary to achieve additional blood pressure reduction.

Angiotensin-II receptor antagonist combined with calcium channel blocker or diuretic for essential hypertension

To achieve the target blood pressure recommended by the latest guidelines, multiple antihypertensive drugs are needed in most patients. In this study, the efficacy of treatment using an angiotensin II receptor antagonist (ARB) combined with a calcium channel blocker (CCB) or a diuretic was compared from multiple perspectives in patients with hypertension. Twenty-nine patients with essential hypertension, who had failed to achieve their target blood pressure (<130/85 mm Hg for patients <65 years old and <140/90 mm Hg for those >/=65 years) when treated with the ARB olmesartan at 20 mg day(-1), were additionally given 8-16 mg day(-1) of the CCB azelnidipine or 1-2 mg day(-1) of trichlormethiazide (a thiazide diuretic) in a randomized crossover manner for 4 months each. At the end of each combination therapy period, blood and urine samples were collected and arterial stiffness was evaluated by measuring the cardio-ankle pulse wave velocity. Compared with monotherapy, the blood pressure was reduced similarly by adding azelnidipine (-12/-10 mm Hg) or trichlormethiazide (-14/-9 mm Hg). The heart rate was decreased with the CCB by 4 b.p.m. (P<0.05), whereas it was unchanged with the thiazide. Serum K, lipids and blood glucose were not significantly changed with either combination, whereas serum uric acid was increased with the thiazide (P<0.01) but was unchanged with azelnidipine. Plasma levels of renin, angiotensin II and aldosterone were also increased with the thiazide period, whereas high-sensitivity C-reactive protein and oxidized low-density lipoprotein were decreased with azelnidipine. In addition, the cardio-ankle vascular index, a parameter of arterial stiffness, was decreased with the azelnidipine period but was unchanged with the thiazide period (P<0.01). It is suggested that the combination of olmesartan and azelnidipine has advantages over the combination of olmesartan and a thiazide with respect to avoiding hyperuricemia, sympathetic activation, renin-angiotensin-aldosterone system stimulation, inflammation, oxidative stress, and increased arterial stiffness in patients with moderate hypertension. These properties may provide cardiovascular protection in addition to the hypotensive effect.

Effect of switching from amlodipine to combination therapy with telmisartan and low-dose hydrochlorothiazide

One of the most effective pairs in combination therapy is that of an inhibitor of the renin-angiotensin system (RAS) and a low-dose thiazide diuretic. Possible candidates for this combination therapy are hypertensive patients with blood pressure (BP) that is not controlled by a calcium channel blocker (CCB). Thus, we characterized the antihypertensive effect of the combination of telmisartan and low-dose hydrochlorothiazide in patients with hypertension that was not controlled by amlodipine, which is the most common CCB. A total of 75 patients with BP levels higher than 140/90 mm Hg, treated with 5 mg per day of amlodipine for at least 3 months, were divided into groups that were switched to treatment with 40-80 mg per day of telmisartan plus 12.5 mg per day of hydrochlorothiazide (TH, n=37) or that were continuously treated with 5-7.5 mg per day of amlodipine (Am, n=38). After 12 weeks of treatment, the mean BP level was significantly lower in the TH group than in the Am group (decrease in BP: -9.9+/-11.4 vs. -3.7+/-8.9 mm Hg, P<0.02; normalization rate: 67.6 vs. 30.3%, P<0.01). Serum uric acid was slightly higher in the TH group, but other laboratory data were not different between groups. Therefore, it is suggested that the combination of a RAS inhibitor and a low-dose thiazide is useful if treatment with a CCB cannot control BP in patients with hypertension.

The evolution of systolic blood pressure as a strong predictor of cardiovascular risk and the effectiveness of fixed-dose ARB/CCB combinations in lowering levels of this preferential target

Elevated blood pressure is an important cardiovascular risk factor. Although targets for both diastolic blood pressure (DBP) and systolic blood pressure (SBP) are defined by current guidelines, DBP has historically taken precedence in hypertension management. However, there is strong evidence that SBP is superior to DBP as a predictor of cardiovascular events. Moreover, achieving control of SBP is assuming greater importance amongst an aging population. In spite of the growing recognition of the importance of SBP in reducing cardiovascular risk and the emphasis by current guidelines on SBP control, a substantial proportion of patients still fail to achieve SBP targets, and SBP control is achieved much less frequently than DBP control. Thus, new approaches to the management of hypertension are required in order to control SBP and minimize cardiovascular risk. Fixed-dose combination (FDC) therapy is an approach that offers the advantages of multiple drug administration and a reduction in regimen complexity that favors compliance. We have reviewed the latest evidence demonstrating the efficacy in targeting SBP of the most recent FDC products; combinations of the calcium channel blocker (CCB), amlodipine, with angiotensin receptor blockers (ARBs), valsartan or olmesartan. In addition, results from studies with new classes of agent are outlined.

Efficacy and tolerability of amlodipine/valsartan combination therapy in hypertensive patients not adequately controlled on valsartan monotherapy

OBJECTIVE

To demonstrate additional BP-lowering effects of amlodipine/valsartan combination in patients whose BP was not adequately controlled on valsartan alone.

METHODS

This was a multi-centre, randomised, double-blind, active-controlled study in patients with essential hypertension. After a washout period followed by a single-blind valsartan 160 mg run-in period, patients with mean sitting diastolic blood pressure (DBP) >or= 90 mmHg and < 110 mmHg were randomised to receive amlodipine/valsartan (10/160 mg or 5/160 mg o.d.) or valsartan (160 mg o.d.) for 8 weeks.

TRIAL REGISTRATION

NCT00170963 MAIN OUTCOME MEASURES: Primary efficacy variable was change from baseline in mean DBP at study end. Secondary efficacy variables included change from baseline in mean sitting systolic blood pressure (SBP), responder rate (mean DBP < 90 mmHg or >or= 10 mmHg reduction from baseline), and DBP control rate (mean DBP < 90 mmHg). Safety was also assessed.

RESULTS

Of 1136 patients enrolled in single-blind phase, 947 (mean age: 54.6 years) were randomised. Statistically significantly greater reductions in mean SBP/DBP were observed in both amlodipine/valsartan combinations (10/160 mg: 14.3/11.5 mmHg, 5/160 mg: 12.2/9.6 mmHg; both p < 0.0001) compared to valsartan 160 mg (8.3/6.7 mmHg). The 10/160 mg combination (p < 0.05) showed statistically significantly greater reductions in mean SBP/DBP compared to 5/160 mg (p < 0.001). Responder rates were higher in both combination therapy groups (10/160 mg: 81% [p < 0.0001]; 5/160 mg: 68% [p = 0.0018], respectively) compared to monotherapy (57%). Peripheral oedema was the most frequent adverse event, reported in amlodipine/valsartan 10/160 mg (9.1%), 5/160 mg (0.9%), and valsartan 160 mg (1.3%).

CONCLUSIONS

The combination of amlodipine/valsartan in this 8-week double-blind study provided additional BP control and was well-tolerated in patients inadequately controlled with valsartan monotherapy.

Application in the STRATHE trial of a score system to compare the efficacy and the tolerability of different therapeutic strategies in the management of hypertension

A score system integrating the evolution of efficacy and tolerability over time was applied to a subpopulation of the STRATHE trial, a trial performed according to a parallel group design, with a double-blind, random allocation to either a fixed-dose combination strategy (perindopril/indapamide 2 mg/0.625 mg, with the possibility to increase the dose to 3 mg/0.935 mg, and 4 mg/1.250 mg if needed, n = 118), a sequential monotherapy approach (atenolol 50 mg, followed by losartan 50 mg and amlodipine 5 mg if needed, n = 108), or a stepped-care strategy (valsartan 40 mg, followed by valsartan 80 mg and valsartan 80 mg+ hydrochlorothiazide 12.5 mg if needed, n = 103). The aim was to lower blood pressure below 140/90 mmHg within a 9-month period. The treatment could be adjusted after 3 and 6 months. Only patients in whom the study protocol was strictly applied were included in this analysis. At completion of the trial the total score averaged 13.1 ± 70.5 (mean ± SD) using the fixed-dose combination strategy, compared with −7.2 ± 81.0 using the sequential monotherapy approach and −17.5 ± 76.4 using the stepped-care strategy. In conclusion, the use of a score system allows the comparison of antihypertensive therapeutic strategies, taking into account at the same time efficacy and tolerability. In the STRATHE trial the best results were observed with the fixed-dose combination containing low doses of an angiotensin enzyme converting inhibitor (perindopril) and a diuretic (indapamide).

Discontinuation of and changes in drug therapy for hypertension among newly-treated patients: a population-based study in Italy

OBJECTIVES

To assess rates and determinants of treatment discontinuation of or changes in initial antihypertensive drug therapy in a large cohort of patients from Lombardia (Italy).

METHODS

The cohort included 445356 patients aged 40 -80 years who received their first antihypertensive drug prescription (monotherapy) during 1999--2002. Discontinuation was defined by the absence of any antihypertensive prescription during a 90-day period following the end of the latest prescription. If during the same period a drug of a different class was added or replaced the initial prescription, treatment modification was regarded as combination or switching, respectively. Competing risks methodology was used to estimate and compare cause-specific cumulative incidence.

RESULTS

Cumulative incidences of discontinuation, combination and switching were respectively 33, 14 and 15% at 6 months, 41, 18 and 17% at 1 year, and 50, 25 and 19% at 5 years since initial treatment. Compared with patients starting treatment with angiotensin-converting enzyme inhibitors, the rate of discontinuation was less for patients on angiotensin receptor blockers with a hazard ratio of 0.92 (95% confidence interval =0.90-0.94), whereas increased discontinuation was observed for patients starting with other drugs, mainly beta-blockers with a hazard ratio of 1.64 (1.62-1.67); and diuretics with a hazard ratio of 1.83 (1.81-1.85).

CONCLUSION

In the general population of Lombardia, discontinuation of the initial single antihypertensive drug treatment is a common phenomenon, whereas switching to another monotherapy and to combination treatment occur at similarly much lower rates. Blockers of the renin-angiotensin system are associated with the lowest incidence of treatment discontinuation.

Effective and safe reduction of blood pressure with the combination of amlodipine 5 mg and valsartan 160 mg in hypertensive patients not controlled by calcium channel blocker monotherapy

INTRODUCTION

The addition of an angiotensin II receptor blocker to calcium channel blocker-based antihypertensive therapy may be associated with enhanced efficacy and reduced risk of adverse events.

METHODS

This 8-week, open-label, single-arm trial evaluated the efficacy and tolerability of the combination of amlodipine and valsartan in patients not responding adequately to treatment with amlodipine or felodipine alone. Patients aged > or =18 years with moderate essential hypertension (defined as mean sitting systolic blood pressure [MSSBP] > or =160 and <180 mmHg) were treated for 4 weeks with once-daily amlodipine 5 mg or felodipine 5 mg. At week 4, patients not adequately responding were treated for an additional 4 weeks with once-daily amlodipine 5 mg plus valsartan 160 mg. Of 214 patients treated for 4 weeks with amlodipine 5 mg or felodipine 5 mg, 181 failed to achieve MSSBP <140 mmHg. These non-responders were treated for an additional 4 weeks with amlodipine 5 mg and valsartan 160 mg.

RESULTS

A clinically and statistically significant additional reduction in MSSBP of 13.1 mmHg (95% confidence interval [CI]: 11.4, 14.7; P<0.0001) and a mean sitting diastolic blood pressure of 5.3 mmHg (95% CI: 4.3, 6.3; P<0.0001) were observed. Of patients treated with amlodipine 5 mg and valsartan 160 mg, 51.1% achieved target blood pressure levels (<140/90 mmHg) after 4 weeks. Adverse event rates were low in both treatment phases, and most were mild or moderate in severity.

CONCLUSION

The combination of amlodipine/valsartan was effective and well tolerated.

The importance of prompt blood pressure control

Hypertension affects almost one-third of adults in the United States, but blood pressure is adequately controlled in only about 50% to 60% of persons with treated hypertension. Abundant clinical trial evidence has shown that antihypertensive therapy significantly reduces the risk of vascular events, and meta-analyses of observational and clinical trials have shown that greater reductions in blood pressure are associated with greater reductions in risk. Recent trials have also suggested that prompt control of blood pressure is beneficial in high-risk patients with hypertension. A post hoc analysis of a trial comparing an angiotensin II receptor blocker-based program with a calcium channel blocker-based treatment regimen found that the blood pressure response after 1 month (regardless of the drug used) predicted the risk of vascular events and survival. Therapy with > or =2 medications given separately or as a fixed combination is more likely than monotherapy to lower blood pressure to goal in part because drugs from different classes target different mechanisms that regulate blood pressure. Moreover, the likelihood of achieving blood pressure goals is greater if the time to achieve control is shortened, and prompt control of blood pressure is more likely with multiple-drug therapy than with monotherapy.

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.

Two multicenter, 8-week, randomized, double-blind, placebo-controlled, parallel-group studies evaluating the efficacy and tolerability of amlodipine and valsartan in combination and as monotherapy in adult patients with mild to moderate essential hypertension

BACKGROUND

Patients with hypertension may require combination therapy to attain the blood pressure targets recommended by US and European treatment guidelines. Combination therapy with a calcium channel blocker and an angiotensin II-receptor blocker would be expected to provide enhanced efficacy.

OBJECTIVES

Two studies were conducted to compare the efficacy of various combinations of amlodipine and valsartan administered once daily with their individual components and placebo in patients with mild to moderate essential hypertension (mean sitting diastolic blood pressure [MSDBP] >/=95 and < 110 mm Hg). A secondary objective was to evaluate safety and tolerability.

METHODS

The 2 studies were multinational, multicenter, 8-week, randomized, double-blind, placebo-controlled, parallel-group trials. In study 1, patients were randomized to receive amlodipine 2.5 or 5 mg once daily, valsartan 40 to 320 mg once daily, the combination of amlodipine 2.5 or 5 mg with valsartan 40 to 320 mg once daily, or placebo. In study 2, patients were randomized to receive amlodipine 10 mg once daily, valsartan 160 or 320 mg once daily, the combination of amlodipine 10 mg with valsartan 160 or 320 mg once daily, or placebo. The primary efficacy variable in both studies was change from baseline in MSDBP at the end of the study. Secondary variables included the change in mean sitting systolic blood pressure (MSSBP), response rate (the proportion of patients achieving an MSDBP <90 mm Hg or a >/= 10-mm Hg decrease from baseline), and control rate (the proportion of patients achieving an MSDBP <90 mm Hg). Safety was assessed in terms of adverse events (spontaneously reported or elicited by questioning), vital signs, and laboratory values.

RESULTS

A total of 1911 patients were randomized to treatment in study 1 (1022 amlodipine + valsartan; 507 valsartan; 254 amlodipine; 128 placebo); 1250 were randomized to treatment in study 2 (419, 415, 207, and 209, respectively). In all treatment groups in both studies, the majority of patients were white (79.5% study 1, 79.4% study 2) and male (53.5% and 50.3%, respectively). The overall mean age was 54.4 years in study 1 and 56.9 years in study 2. The mean weight of patients in study 1 was higher than that in study 2 (88.8 vs 79.7 kg). The overall baseline mean sitting BP was 152.8/99.3 mm Hg in study 1 and 156.7/99.1 mm Hg in study 2. With the exception of a few combinations that included amlodipine 2.5 mg, the combination regimens in both studies were associated with significantly greater reductions in MSDBP and MSSBP compared with their individual components and placebo (P < 0.05). A positive dose response was observed for all combinations. The highest response rate in study 1 was associated with the highest dose of combination therapy (amlodipine 5 mg + valsartan 320 mg: 91.3%). Amlodipine 5 mg, valsartan 320 mg, and placebo were associated with response rates of 71.9%, 73.4%, and 40.9%, respectively. In study 2, the 2 doses of combination therapy were associated with similar response rates (amlodipine 10 mg + valsartan 160 mg: 88.5%; amlodipine 10 mg + valsartan 320 mg: 87.5%). Amlodipine 10 mg was associated with a response rate of 86.9%; valsartan 160 and 20 mg were associated with response rates of 74.9% and 72.0%, respectively; and placebo was associated with a response rate of 49.3%. Control rates followed a similar pattern. The incidence of peripheral edema with combination therapy was significantly lower compared with amlodipine monotherapy (5.4% vs 8.7%, respectively; P = 0.014), was significantly higher compared with valsartan monotherapy (2.1%; P < 0.001), and did not differ significantly from placebo (3.0%).

CONCLUSIONS

In these adult patients with mild to moderate hypertension, the combination of amlodipine + valsartan was associated with significantly greater blood pressure reductions from baseline compared with amlodipine or valsartan monotherapy or placebo. The incidence of peripheral edema was significantly lower with combination therapy than with amlodipine monotherapy.

Clinical practice and recent recommendations in hypertension management--reporting a gap in a global survey of 1259 primary care physicians in 17 countries

OBJECTIVE

High blood pressure (BP) is a leading risk factor for cardiovascular morbidity and mortality. Effective antihypertensive pharmacotherapy is available but recognition and proper management of hypertension and BP goal achievement is still poor. Therefore, it was hypothesized that physicians' attitude towards high BP, as well as patients' perception and knowledge, may influence actual management of hypertension.

RESEARCH DESIGN AND METHODS

Telephone interviews were carried out with a random sample of 1259 primary care physicians in 17 countries worldwide from 12 December 2005 to 13 January 2006 using a central computer assisted telephone interview methodology (CATI).

RESULTS

(1) Physicians believed that 62 +/- 21% of their patients had their BP controlled. (2) They were mostly in line with guideline recommended BP goals and 96% were aware of the elevated cardiovascular risk of hypertension, but 41% aimed to reduce BP to acceptable levels only. (3) Physicians indicated that in 41% of patients monotherapy controls BP and 71% would escalate to combination therapy after monotherapy failure. (4) 54% regard hypertension management as difficult. (5) Physicians estimated that between 60 and 70% of patients know their BP goal but thought that there was still room for improvement of hypertension management on the patient side.

CONCLUSION

Although many effective treatment options for arterial hypertension exist, BP goal achievement worldwide is suboptimal, leaving patients at an unnecessary cardiovascular risk. An increase in patients' awareness and compliance together with an increased adherence of physicians to current guidelines should help in reducing the long term cardiovascular consequences of hypertension.

Combination drug treatment of hypertension: Have we come full circle?

Only 30% of hypertensive patients achieved and maintained adequate blood pressure control on a single drug in recent clinical trials. For the majority of patients who require two or more drugs to lower blood pressure to the currently recommended goals of 140/90 mm Hg or to 130/80 if they are diabetic or have chronic kidney disease, combinations of two or more drugs in a single pill offers an attractive alternative to taking multiple single drugs each day. Research has shown that the simpler the drug regimen the more likely patients are to be compliant in taking medications. Because a reduction in cardiovascular risk is linked to the extent to which elevated blood pressure is reduced, this benefit is not realized by patients who either discontinue their medications or are noncompliant. Carefully selected low doses of two antihypertensive drugs combined in a single pill offers other advantages including greater efficacy compared with high-dose monotherapy, a lower incidence of adverse effects, improved persistence in taking medications, fewer patient visits, and reduced cost to the health care system.

Achieving goal blood pressure in patients with type 2 diabetes: conventional versus fixed-dose combination approaches

Data from the Third National Health and Nutrition Examination Survey (NHANES III) demonstrate that only 11% of people with diabetes who are treated for high blood pressure achieve the blood pressure goal of <130/85 mm Hg recommended in the sixth report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC VI). The current study tests the hypothesis that initial therapy with a fixed-dose combination will achieve the recommended blood pressure goal in patients with type 2 diabetes faster than conventional monotherapy. This randomized, double-blind, placebo-controlled study had as a primary end point achievement of blood pressure <130/85 mm Hg. Participants (N=214) with hypertension and type 2 diabetes received either amlodipine/benazepril 5/10 mg (combination) or enalapril 10 mg (conventional) once daily for 4 weeks, titrated to 5/20 mg/day or 20 mg/day, respectively at this time, if target blood pressure was not achieved. Hydrochlorothiazide (HCTZ) 12.5 mg/day was added for the final 4 weeks, if target blood pressure was still not reached. Time from baseline to achieve blood pressure <130/85 mm Hg was shorter in the combination group (5.3+/-3.1 weeks combination vs. 6.4+/-3.8 weeks conventional; p=0.001). At 3 months, more participants in the combination group achieved treatment goal (63% combination vs. 37% conventional; p=0.002). Data analysis at 3 months comparing blood pressure control rates between the fixed-dose combination group (without HCTZ) to the conventional group (receiving HCTZ) showed an even greater disparity in blood pressure goal achievement (87% combination without HCTZ vs. 37% conventional group with HCTZ; p=0.0001). We conclude that initial therapy with a fixed-dose combination may be more efficacious than conventional monotherapy approaches for achieving blood pressure goals in the diabetic patient. A fixed-dose combination approach appears as safe as the current conventional approaches.