Combination is better than monotherapy with ACE inhibitor or angiotensin receptor antagonist at recommended doses

Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers for adults with early (stage 1 to 3) non-diabetic chronic kidney disease

BACKGROUND

Chronic kidney disease (CKD) is a long-term condition that occurs as a result of damage to the kidneys. Early recognition of CKD is becoming increasingly common due to widespread laboratory estimated glomerular filtration rate (eGFR) reporting, raised clinical awareness, and international adoption of the Kidney Disease Improving Global Outcomes (KDIGO) classifications. Early recognition and management of CKD affords the opportunity to prepare for progressive kidney impairment and impending kidney replacement therapy and for intervention to reduce the risk of progression and cardiovascular disease. Angiotensin-converting enzyme inhibitors (ACEi) and angiotensin receptor blockers (ARB) are two classes of antihypertensive drugs that act on the renin-angiotensin-aldosterone system. Beneficial effects of ACEi and ARB on kidney outcomes and survival in people with a wide range of severity of kidney impairment have been reported; however, their effectiveness in the subgroup of people with early CKD (stage 1 to 3) is less certain. This is an update of a review that was last published in 2011.

OBJECTIVES

To evaluate the benefits and harms of ACEi and ARB or both in the management of people with early (stage 1 to 3) CKD who do not have diabetes mellitus (DM).

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 6 July 2023 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and Embase, conference proceedings, the International Clinical Trials Registry Platform (ICTRP) Search Portal, and ClinicalTrials.gov.

SELECTION CRITERIA

Randomised controlled trials (RCTs) reporting the effect of ACEi or ARB in people with early (stage 1 to 3) CKD who did not have DM were selected for inclusion. Only studies of at least four weeks duration were selected. Authors independently assessed the retrieved titles and abstracts and, where necessary, the full text to determine which satisfied the inclusion criteria.

DATA COLLECTION AND ANALYSIS

Data extraction was carried out by two authors independently, using a standard data extraction form. The methodological quality of included studies was assessed using the Cochrane risk of bias tool. Data entry was carried out by one author and cross-checked by another. When more than one study reported similar outcomes, data were pooled using the random-effects model. Heterogeneity was analysed using a Chi² test and the I² test. Results were expressed as risk ratios (RR) and their 95% confidence intervals (CI) for dichotomous outcomes and mean difference (MD) and 95% CI for continuous outcomes. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach MAIN RESULTS: Six studies randomising 9379 participants with CKD stages 1 to 3 (without DM) met our inclusion criteria. Participants were adults with hypertension; 79% were male from China, Europe, Japan, and the USA. Treatment periods ranged from 12 weeks to three years. Overall, studies were judged to be at unclear or high risk of bias across all domains, and the quality of the evidence was poor, with GRADE rated as low or very low certainty. In low certainty evidence, ACEi (benazepril 10 mg or trandolapril 2 mg) compared to placebo may make little or no difference to death (any cause) (2 studies, 8873 participants): RR 2.00, 95% CI 0.26 to 15.37; I² = 76%), total cardiovascular events (2 studies, 8873 participants): RR 0.97, 95% CI 0.90 to 1.05; I² = 0%), cardiovascular-related death (2 studies, 8873 participants): RR 1.73, 95% CI 0.26 to 11.66; I² = 54%), stroke (2 studies, 8873 participants): RR 0.76, 95% CI 0.56 to 1.03; I² = 0%), myocardial infarction (2 studies, 8873 participants): RR 1.00, 95% CI 0.84 to 1.20; I² = 0%), and adverse events (2 studies, 8873 participants): RR 1.33, 95% CI 1.26 to 1.41; I² = 0%). It is uncertain whether ACEi (benazepril 10 mg or trandolapril 2 mg) compared to placebo reduces congestive heart failure (1 study, 8290 participants): RR 0.75, 95% CI 0.59 to 0.95) or transient ischaemic attack (1 study, 583 participants): RR 0.94, 95% CI 0.06 to 15.01; I² = 0%) because the certainty of the evidence is very low. It is uncertain whether ARB (losartan 50 mg) compared to placebo (1 study, 226 participants) reduces: death (any-cause) (no events), adverse events (RR 19.34, 95% CI 1.14 to 328.30), eGFR rate of decline (MD 5.00 mL/min/1.73 m2, 95% CI 3.03 to 6.97), presence of proteinuria (MD -0.65 g/24 hours, 95% CI -0.78 to -0.52), systolic blood pressure (MD -0.80 mm Hg, 95% CI -3.89 to 2.29), or diastolic blood pressure (MD -1.10 mm Hg, 95% CI -3.29 to 1.09) because the certainty of the evidence is very low. It is uncertain whether ACEi (enalapril 20 mg, perindopril 2 mg or trandolapril 1 mg) compared to ARB (olmesartan 20 mg, losartan 25 mg or candesartan 4 mg) (1 study, 26 participants) reduces: proteinuria (MD -0.40, 95% CI -0.60 to -0.20), systolic blood pressure (MD -3.00 mm Hg, 95% CI -6.08 to 0.08) or diastolic blood pressure (MD -1.00 mm Hg, 95% CI -3.31 to 1.31) because the certainty of the evidence is very low.

AUTHORS' CONCLUSIONS

There is currently insufficient evidence to determine the effectiveness of ACEi or ARB in patients with stage 1 to 3 CKD who do not have DM. The available evidence is overall of very low certainty and high risk of bias. We have identified an area of large uncertainty for a group of patients who account for most of those diagnosed as having CKD.

Efficacy and safety of dual vs single renin-angiotensin-aldosterone system blockade in chronic kidney disease: An updated meta-analysis of randomized controlled trials

BACKGROUND

To lower albuminuria and to achieve blood pressure (BP) goals, dual renin-angiotensin-aldosterone system (RAAS) inhibitors are sometimes used in clinical practice for the treatment of CKD. However, the efficacy and safety of dual RAAS blockade therapy remains controversial.

METHODS

PubMed, EMBASE, and Cochrane Library were searched, and random effects model was used to calculate the effect sizes of eligible studies. Potential sources of heterogeneity were detected by meta-regression and subgroup analysis.

RESULTS

The present meta-analysis of 72 randomized controlled trials with 10,296 patients demonstrated that dual RAAS blockade therapy was superior to monotherapy in reducing the urine albumin excretion, urine protein excretion, and BP. These beneficial effects were related to the decrease of glomerular filtration rate, the increase of serum potassium level, and higher rates of hyperkalemia and hypotension. Meanwhile, these effects did not lead to improvements in short-term or long-term outcomes, including doubling of serum creatinine, acute kidney injury, end-stage renal disease, mortality, and hospitalization. Compared with the single therapy, angiotensin-converting enzyme inhibitor (ACEI) in combination with angiotensin-receptor blocker (ARB) was a better dual therapy than ACEI or ARB in combination with renin inhibitor or aldosterone receptor antagonist in decreasing urine albumin excretion, urine protein excretion and BP, and the combination was not associated with a lower glomerular filtration rate.

CONCLUSION

Compared with the single therapy, ACEI in combination with ARB was a better dual therapy than ACEI or ARB in combination with renin inhibitor or aldosterone receptor antagonist. Although ACEI in combination with ARB was associated with higher incidences of hyperkalemia and hypotension, careful individualized management and potassium binders may further expand its application (PROSPERO number CRD42020179398).

Efficacy and Safety of Angiotensin-Converting Enzyme Inhibitor in Combination with Angiotensin-Receptor Blocker in Chronic Kidney Disease Based on Dose: A Systematic Review and Meta-Analysis

Background: The purpose of this meta-analysis was to evaluate the controversy of angiotensin-converting enzyme inhibitor (ACEI) in combination with angiotensin-receptor blocker (ARB) in the treatment of chronic kidney disease (CKD) based on dose.

Methods: PubMed, EMBASE, and Cochrane Library were searched to identify randomized controlled trials (RCTs) from inception to March 2020. The random effects model was used to calculate the effect sizes. Potential sources of heterogeneity were detected using sensitivity analysis and meta-regression.

Results: This meta-analysis of 53 RCTs with 6,375 patients demonstrated that in patients with CKD, ACEI in combination with ARB was superior to low-dose ACEI or ARB in reducing urine albumin excretion (SMD, −0.43; 95% CI, −0.67 to −0.19; p = 0.001), urine protein excretion (SMD, −0.22; 95% CI, −0.33 to −0.11; p < 0.001), and blood pressure (BP), including systolic BP (WMD, −2.89; 95% CI, −3.88 to −1.89; p < 0.001) and diastolic BP (WMD, −3.02; 95% CI, −4.46 to −1.58; p < 0.001). However, it was associated with decreased glomerular filtration rate (GFR) (SMD, −0.13; 95% CI, −0.24 to −0.02; p = 0.02) and increased rates of hyperkalemia (RR, 2.07; 95% CI, 1.55 to 2.76; p < 0.001) and hypotension (RR, 2.19; 95% CI, 1.35 to 3.54; p = 0.001). ACEI in combination with ARB was more effective than high-dose ACEI or ARB in reducing urine albumin excretion (SMD, −0.84; 95% CI, −1.26 to −0.43; p < 0.001) and urine protein excretion (SMD, −0.24; 95% CI, −0.39 to −0.09; p = 0.002), without decrease in GFR (SMD, 0.02; 95% CI, −0.12 to 0.15; p = 0.78) and increase in rate of hyperkalemia (RR, 0.94; 95% CI, 0.65 to 1.37; p = 0.76). Nonetheless, the combination did not decrease the BP and increased the rate of hypotension (RR, 3.95; 95% CI, 1.13 to 13.84; p = 0.03) compared with high-dose ACEI or ARB.

Conclusion: ACEI in combination with ARB is superior in reducing urine albumin excretion and urine protein excretion. The combination is more effective than high-dose ACEI or ARB without decreasing GFR and increasing the incidence of hyperkalemia. Despite the risk of hypotension, ACEI in combination with ARB is a better choice for CKD patients who need to increase the dose of ACEI or ARB (PROSPERO CRD42020179398).

Combined Treatment With Angiotensin-Converting Enzyme Inhibitors and Angiotensin II Receptor Blockers: A Review of the Current Evidence

Several studies have shown that angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers are useful in the treatment of hypertension, cardiovascular disease, chronic heart failure, and some types of nephropathy. In this context, dual renin-angiotensin system blockade with both angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers may be more effective than treatment with each agent alone. Many clinical trials have demonstrated the beneficial effect of this combined treatment on proteinuria, hypertension, heart failure, and cardiovascular events. Moreover, these studies demonstrated that dual renin-angiotensin system blockade is generally safe and well tolerated. Long-term studies are under way to confirm these effects and also investigate the effectiveness of dual reninangiotensin system blockade on cerebrovascular disease and prevention of type 2 diabetes mellitus. These studies are expected to define the optimal use of combination treatment in everyday clinical practice. This review considers the most important clinical trials that evaluated the effect of dual renin-angiotensin system blockade on blood pressure, heart failure, and renal function.

Drug therapies to delay the progression of chronic kidney disease

Chronic kidney disease (CKD) is associated with significant morbidity and mortality, impacted not alone by progression to end-stage kidney disease, but also by the high associated incidence of cardiovascular events and related mortality. Despite our current understanding of the pathogenesis of CKD and the treatments available, the reported incidence of CKD continues to rise worldwide, and is often referred to as the silent public healthcare epidemic. The significant cost to patient wellbeing and to the economy of managing the later stages of CKD have prompted efforts to develop interventions to delay the development and progression of this syndrome. In this article, we review established and novel agents that may aid in delaying the progression of CKD and improve patient outcomes.

Meta-analysis: the efficacy and safety of combined treatment with ARB and ACEI on diabetic nephropathy

OBJECTIVE

Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) reduce proteinuria in diabetic nephropathy (DN). Some studies have suggested that dual blockade of the renin-angiotensin system provides additive benefits in DN but others showed increased adverse events. We performed a meta-analysis to evaluate the efficacy and safety of combination therapy for DN.

METHODS

Studies were identified by searching MEDLINE, EMBASE, PubMed, and CNKI. All trials involved ACEI + ARB (combination therapy), and ACEI or ARB alone (monotherapy) for DN. The outcomes measured were urinary total proteinuria (UTP), urinary albumin excretion rate (UAER), serum creatinine, glomerular filtration rate (GFR), end-stage renal disease (ESRD), hyperkalemia, hypotension, and acute kidney injury (AKI).

RESULTS

In the 32 included trials, 2596 patients received combination therapy and 3947 received monotherapy. UTP and UAER were significantly reduced by combined treatment compared with monotherapy. It was notable that low doses of combination therapy reduced UTP more than high doses. Serum creatinine, GFR, and ESRD were not significantly different between the two groups. In severe DN, the occurrence of hyperkalemia and AKI were higher with combination therapy. However, in mild DN, the prevalence of hyperkalemia and AKI were the same in both the groups. In mild DN, the occurrence of hypotension was higher with combination therapy; however, in severe DN, it was not different between the two groups.

CONCLUSION

Our meta-analysis suggests that combination therapy can be used on DN with proteinuria, but should be used with caution in those with decreased renal function, especially with severe renal failure.

Efficacy and safety of combined vs. single renin-angiotensin-aldosterone system blockade in chronic kidney disease: a meta-analysis

BACKGROUND

Although dual blockade of the renin-angiotensin-aldosterone system (RAAS) has gained popularity for the treatment of kidney disease, its benefits and potential risks have not been fully elucidated. We conducted a meta-analysis of all randomized controlled trials comparing the efficacy and safety of combined vs. single RAAS blockade therapy in chronic kidney disease (CKD).

METHODS

We performed a literature search using MEDLINE, the Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, scientific abstracts from meetings, and bibliographies of retrieved articles. We used random-effects models to compute net changes and rate differences in variables.

RESULTS

Fifty-nine (25 crossover and 34 parallel-arm) randomized controlled trials (RCTs) comparing the efficacy and safety of combined vs. single RAAS blockade therapy in CKD were identified (4,975 patients). Combined RAAS blockade therapy was associated with a significant net decrease in glomerular filtration rate (GFR) (-1.8ml/min or ml/min/1.73 m(2); P = 0.005), albuminuria (-90mg/g of creatinine; P = 0.001 or -32mg/day; P = 0.03), and proteinuria (-291mg/g; P = 0.003 or -363mg/day; P < 0.001). Combined RAAS blockade therapy was associated with a 9.4% higher rate of regression to normoalbuminuria and a 5% higher rate of achieving the blood pressure (BP) goal (as defined in individual trials). However, combined RAAS blockade therapy was associated with a significant net increase in serum potassium level, a 3.4% higher rate of hyperkalemia, and a 4.6% higher rate of hypotension. There was no effect on doubling of the serum creatinine level, hospitalization, or mortality.

CONCLUSIONS

Although combined RAAS blockade therapy in CKD is associated with a decrease in albuminuria and proteinuria, it is associated with a decrease in GFR and a higher incidence of hyperkalemia and hypotension relative to monotherapy. The potential long-term kidney benefits of combined RAAS blockade therapy require further study.

Angiotensin-converting enzyme inhibitors, angiotensin receptor blockers and combined therapy in patients with micro- and macroalbuminuria and other cardiovascular risk factors: a systematic review of randomized controlled trials

BACKGROUND

A recent clinical trial showed harmful renal effects with the combined use of angiotensin-converting enzyme inhibitors (ACEI) and angiotensin-II receptor blockers (ARB) in people with diabetes or vascular disease. We examined the benefits and risks of these agents in people with albuminuria and one or more cardiovascular risk factors.

METHODS

MEDLINE, EMBASE and Renal Health Library were searched for trials comparing ACEI, ARB or their combination with placebo or with one another in people with albuminuria and one or more cardiovascular risk factor.

RESULTS

Eighty-five trials (21,708 patients) were included. There was no significant reduction in the risk of all-cause mortality or fatal cardiac-cerebrovascular outcomes with ACEI versus placebo, ARB versus placebo, ACEI versus ARB or with combined therapy with ACEI + ARB versus monotherapy. There was a significant reduction in the risk of nonfatal cardiovascular events with ACEI versus placebo but not with ARB versus placebo, ACEI versus ARB or with combined therapy with ACEI + ARB versus monotherapy. Development of end-stage kidney disease and progression of microalbuminuria to macroalbuminuria were reduced significantly with ACEI versus placebo and ARB versus placebo but not with combined therapy with ACEI + ARB versus monotherapy.

CONCLUSIONS

ACEI and ARB exert independent renal and nonfatal cardiovascular benefits while their effects on mortality and fatal cardiovascular disease are uncertain. There is a lack of evidence to support the use of combination therapy. A comparative clinical trial with ACE, ARB and its combination in people with albuminuria and a cardiovascular risk factor is warranted.

Diuretic uptitration with half dose combined ACEI + ARB better decreases proteinuria than combined ACEI + ARB uptitration

BACKGROUND

Residual proteinuria is a strong modifiable risk factor for renal failure progression. We previously showed that the antiproteinuric effect of combined half doses of angiotensin-converting enzyme inhibitor (ACEI) and angiotensin receptor blocker (ARB) is increased by raising diuretic dosage. Methods. We tested whether uptitration of loop diuretics on top of combined half doses of ACEI and ARB would better decrease proteinuria than uptitration to combined full doses of ACEI and ARB in a randomized, crossover, three periods of 6-week controlled study. Eighteen patients with stable proteinuria over 1 g/day with combined ramipril at 5 mg/day and valsartan at 80 mg/day in addition to conventional antihypertensive treatments were randomized to receive combined ramipril at 5 mg/day and valsartan at 80 mg/day, or combined ramipril at 10 mg/day and valsartan at 160 mg/day, or combined ramipril at 5 mg/day, valsartan at 80 mg/day and increased furosemide dosage in random order. The primary end point was the mean urinary protein/creatinine ratio in two 24-hour urine collections at the end of the three treatment periods. Secondary end points included mean 24-hour proteinuria, home systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial blood pressure (MAP) and estimated glomerular filtration rate (eGFR) levels.

RESULTS

The geometric mean urinary protein/creatinine ratio was lower with combined ramipril at 5 mg/day, valsartan at 80 mg/day and increased furosemide dosage compared to combined ramipril at 5 mg/day and valsartan at 80 mg/day, but also to combined ramipril at 10 mg/day and valsartan at 160 mg/day. These differences remained significant after adjustment for SBP, DBP or MAP and 24-hour natriuresis but not after adjustment on eGFR. Diuretic dosage uptitration did not increase the number of home systolic blood pressure measurements below 100 mmHg, but led to a statistically significant increase in the number of symptomatic hypotension episodes.

CONCLUSIONS

A cautious uptitration of loop diuretic dosage in addition to combined half doses of ACEI and ARB better decrease proteinuria in patients with CKD and high residual proteinuria than uptitration to full dose of combined ACEI and ARB. This antiproteinuric effect of diuretics was partly explained by an eGFR decrease, suggesting the contribution of haemodynamic modifications, whose safety on the long term still need to be addressed.

Renal protective effect of RAAS blockade across the renal continuum, with a review of the efficacy and safety of valsartan

Abstract Objective: The purpose of this report is to review key data on the angiotensin receptor blocker (ARB) valsartan, along with data from several pivotal studies with other ARBs and angiotensin-converting enzyme (ACE) inhibitors, to highlight the beneficial class effects of renin-angiotensin-aldosterone system (RAAS) blockade throughout the renal continuum.

METHODS

The selection of articles was based on a search of PubMed for clinical trials published between 1997 (the year in which valsartan was approved for sale in the US) and 2009 that involved valsartan and reported effects on renal function, plus a select range of articles on other agents acting on the RAAS, including key guidance documents issued during this time.

SUMMARY

Valsartan has been studied extensively and is widely used for the management of hypertension. Data from clinical studies involving valsartan and other ARBs and ACE inhibitors provide evidence of an additional renal protective effect. This renal protection apparently arises from hemodynamic, endothelial, and anti-inflammatory actions.

LIMITATIONS

Given the extent of the available literature on this topic, this review included only a subset of available publications. This report may reflect inherent heterogeneity between patient populations from these studies and also incorporate the limitations of these individual publications. The inclusion of guidance documents from several organizations may have resulted in apparent minor conflicts in the approaches of the different groups.

ACE inhibitors, angiotensin receptor blockers and direct renin inhibitors in combination: a review of their role after the ONTARGET trial

BACKGROUND

Clinical trials have shown organ-protective effects of angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs); however, cardiovascular mortality and morbidity rates, and decline in renal function remain high. In the ONTARGET trial in patients with hypertension at high cardiovascular risk, ACE inhibitor/ARB combination therapy provided no significant clinical outcome benefits over monotherapy, and was associated with a worse safety and tolerability profile. These results raise the question of whether ACE inhibitor/ARB, direct renin inhibitor (DRI)/ACE inhibitor and DRI/ARB combinations are of clinical value.

SCOPE

Using PubMed and EMBASE databases, we conducted a systematic review of clinical trials published before June 2008 evaluating dual intervention with ACE inhibitors and ARBs, and compared these with trials of DRI/ACE inhibitor or DRI/ARB combinations.

FINDINGS

A total of 70 studies met the inclusion criteria for this analysis. In patients with hypertension, ACE inhibitor/ARB combinations provided limited additional reductions in blood pressure (BP) over monotherapy. Outcomes benefits were unclear: VALIANT and ONTARGET demonstrated no enhanced outcome benefit of combination therapy over monotherapy; Val-HeFT and CHARM-Added showed reduced morbidity/mortality in patients with heart failure, but at the expense of poorer tolerability. Combination therapy with the DRI aliskiren and an ACE inhibitor or ARB provided significant additional BP reductions over monotherapy in patients with mild-to-moderate hypertension, and reduced surrogate markers of organ damage in patients with heart failure or diabetic nephropathy, with generally similar safety and tolerability to the component monotherapies. No morbidity and mortality data for DRI/ACE inhibitor or DRI/ARB combinations are currently available.

CONCLUSIONS

ACE inhibitor/ARB combinations showed equivocal effects on clinical outcomes. DRI/ACE inhibitor and DRI/ARB combinations reduced markers of organ damage, but longer-term trials are required to establish whether more complete renin--angiotensin--aldosterone system control with aliskiren-based therapy translates into improved outcome benefits.

A comparative study of the prevalence of hyperkalemia with the use of angiotensin-converting enzyme inhibitors versus angiotensin receptor blockers

Background and objectives

Angiotensin-converting enzyme inhibitors (ACEI) and angiotensin receptor blockers (ARB) are increasingly used in a variety of settings including heart failure, renal failure, arterial hypertension, and diabetic nephropathy. The objective of this study was to investigate the prevalence of hyperkalemia with ACEI and ARB use, in a population of the United States veterans.

Design, settings, material, and measurements

Retrospective observational cohort study of 1163 patients on ACEIs and 1168 patients on ARBs in a single Veterans Affairs Medical Center. Electronic medical records were reviewed over a 12-month period with data collected on various demographic, laboratory, comorbidity, and medication related variables.

Results

Hyperkalemia (>5 mEq/L) was observed in 20.4% of patients on ACEIs and 31.0% on ARBs. Severe hyperkalemia (6 mEq/L or higher), was observed in 0.8% of ACEI and 2.8% of ARB users. In univariate logistic regression analyses, diabetes mellitus; serum glucose, total carbon dioxide content, creatinine, and estimated glomerular filtration rate (GFR) were significantly associated with hyperkalemia. ARB use, when compared to ACEI, was associated with a 42% increase in odds of hyperkalemia (odds ratio [OR] = 1.42; p = 0.001) in a model including adjustment for GFR and a 56% increase in odds of hyperkalemia (OR = 1.56; p < 0.001) in a model including adjustment for serum creatinine.

Conclusions

Hyperkalemia, associated with the use of ACEIs and ARBs, is usually mild and severe hyperkalemia is rare. Hyperkalemia is more common with ARBs than ACEIs. ARB use, when compared to ACEI use, may significantly and independently be associated with increased odds of hyperkalemia.

Review: Renal protection by inhibition of the renin-angiotensin-aldosterone system

Renin-angiotensin-aldosterone system (RAAS) inhibition exerts a renoprotective effect independent of blood pressure reduction. Many studies using an end-point of proteinuria compared the effects of angiotensin-converting enzyme inhibitor (ACE-I) or angiotensin receptor blocker (ARB) monotherapy with combination ACE-I/ARB therapy. Despite methodological limitations, most studies suggest that combination therapy provides a greater antiproteinuric effect than monotherapy, perhaps because of more prolonged and complete RAAS inhibition. COOPERATE and ONTARGET used more robust end-points to study renoprotective effects. In COOPERATE, combination therapy resulted in significantly longer times to doubling serum creatinine or developing end-stage renal disease than trandolapril or losartan monotherapy. However, a secondary ONTARGET finding was that combination therapy significantly increased the risk for renal dysfunction compared with ramipril or telmisartan alone. Eventually, the VA NEPHRON-D trial should provide definitive data relating to patients with diabetic nephropathy. Results of AVOID suggest the renoprotective benefits of combination therapy extend to the direct renin inhibitors (DRI). In AVOID, combination therapy with aliskiren, a DRI, and losartan resulted in 20% greater protein excretion decrement than losartan monotherapy. Future trials should examine higher RAAS inhibitor doses, facilitate differentiation of renoprotective and antihypertensive effects of RAAS blockade, and use end-points that robustly demonstrate renoprotective effects.

Improvement of blood pressure control in hypertensive patients with renal diseases

For hypertensive patients with renal diseases (RD), strict blood pressure (BP) control has been recommended in recent hypertension guidelines, such as JNC VI, JNC 7, WHO/ISH 1999 and ESH-ESC 2003. We assessed the current status of BP control and the changes of BP control before and after the publication of these guidelines in 489 hypertensive patients with or without RD (age, 19-89 years, mean 59+/-13 years) who visited the hypertension and kidney outpatient clinic at Kyushu University Hospital. The clinical characteristics of RD and non-RD patients were assessed (RD patients: age, 20-89 years, mean 60+/-13 years, n=311; non-RD patients: age, 19-86 years, mean 58+/-13 years, n=178). In addition, we compared the BP control status in 2003 to that in 1996. In 2003, the BP in RD patients was 134+/-16/78+/-10 mmHg and that in non-RD patients was 138+/-12/83+/-9 mmHg. When strict BP control was defined as <130/80 mmHg, the frequency of strict BP control in RD patients was 28.9% in 2003. In addition, the BP levels of RD patients in 2003 were significantly lower than those in 1996 (134+/-16/78+/-10 mmHg vs. 141+/-17/85+/-10 mmHg, p<0.05 for both systolic blood pressure [SBP] and diastolic blood pressure [DBP]), and the frequency of strict BP control in RD patients was higher in 2003 than in 1996 (28.9% vs. 11.8%, p<0.01). The BP levels of non-RD patients in 2003 tended to be lower than those in 1996 (138+/-12/83+/-9 mmHg vs. 141+/-13/85+/-9 mmHg, n.s.). In 2003, angiotensin II receptor blockers (ARBs) were more frequently prescribed to RD patients than to non-RD patients. Furthermore, the use of ARBs was markedly increased in 2003 compared with 1996. In conclusion, in our outpatient clinic, BP levels in hypertensive patients with RD have improved in recent years, and were lower than those in hypertensive patients without RD, which may in part reflect the physicians' awareness of the importance of strict BP control in RD patients, as suggested by several recent hypertension guidelines.

Combination Angiotensin-Converting Enzyme Inhibitor and Angiotensin Receptor Blocker Therapy: Its Role in Clinical Practice

Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers are commonly prescribed for the management of hypertension. In addition, each of these drug classes has been shown to be effective in the treatment of congestive heart failure, proteinuric chronic kidney disease, and most recently the high-cardiac-risk profile patient. The individual success of each of these drug classes has fueled the theory that given together, the overall biologic effect of both would surpass that of either given alone. The foundation of this premise, although biologically plausible, has yet to be proven in a compelling enough fashion to support the everyday use of these two drug classes in combination. Additional clarifying studies are required to establish whether specific patient subsets exist that might benefit from such combination therapy.

Comparison of higher dose of losartan treatment with losartan plus carvedilol and losartan plus ramipril in patients with glomerulonephritis and proteinuria

BACKGROUND

Proteinuria may cause a worsening of accompanying renal disease or even lead to glomerulosclerosis. There is no data about the effect of carvedilol on patients with proteinuric (>0.5 g/day) glomerulonephritis. This study aimed to compare the effects of carvedilol with ramipril and losartan in patients with proteinuric glomerulonephritis.

METHODS

Twenty-one glomerulonephritis patients were followed for 12 months. Patients were divided into three groups. All patients were treated with losartan 50 mg once daily for two weeks. After two weeks (baseline), patients were given additional medications: 50 mg losartan, 5 mg ramipril, and 25 mg carvedilol were given additionally to the patients in groups 1, 2, and 3 respectively.

RESULTS

Baseline mean proteinuria values of patients in groups 1, 2 and 3 were 1.6 +/- 1.1 g/day, 2.1 +/- 1.3 g/day, and 1.4 +/- 1.2 g/day, respectively. These values decreased to 0.5 +/- 0.7 g/day, 0.6 +/- 0.7 g/day, and 0.9 +/- 0.9 g/day, respectively, at the end of the 12th month. These results were statistically significant only in group 1 (p = 0.04). The rational variation of proteinuria between the first and 12th month of losartan, ramipril, and carvedilol were -61%, -62%, and -27%, respectively. The decreases in blood pressures between baseline and the first, sixth, and twelfth-month measurements were significant in all groups.

CONCLUSIONS

Thee results showed that angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (AT1ras) provide marked decreases in proteinuria, making their use indisputable in patients with glomerulonephritis. Carvedilol was not found to be as effective as ACEIs and AT1ras in decreasing proteinuria and preserving renal function.

The Future of Antihypertensive Treatment

Despite progress in recent years in the prevention, detection, and treatment of high blood pressure (BP), hypertension remains an important public health challenge. Hypertension affects approximately 1 billion individuals worldwide. High BP is associated with an increased risk of mortality and morbidity from stroke, coronary heart disease, congestive heart failure, and end-stage renal disease; it also has a negative impact on the quality of life. Hypertension cannot be eliminated because there are no vaccines to prevent the development of hypertension, but, its incidence can be decreased by reducing the risk factors for its development, which include obesity, high dietary intake of fat and sodium and low intake of potassium, physical inactivity, smoking, and excessive alcohol intake. For established hypertension, efforts are to be directed to control BP by lifestyle modification (LSM). However, if BP cannot be adequately controlled with LSM, then pharmacotherapy can be instituted along with LSM. Normalization of BP reduces cardiovascular risk (for cardiovascular death, myocardial infarction, and cardiac arrest), provides renoprotection (prevention of the onset or slowing of proteinuria and progression of renal dysfunction to end-stage renal disease in patients with hypertension, diabetes mellitus types 1 and 2, and chronic renal disease), and decreases the risk of cerebrovascular events (stroke and cognition impairment), as has been amply demonstrated by a large number of randomized clinical trials. In spite of the availability of more than 75 antihypertensive agents in 9 classes, BP control in the general population is at best inadequate. Therefore, antihypertensive therapy in the future or near future should be directed toward improving BP control in treated hypertensive patients with the available drugs by using the right combinations at optimum doses, individually tailored gene-polymorphism directed therapy, or development of new modalities such as gene therapy and vaccines. Several studies have shown that BP can be reduced by lifestyle/behavior modification. Although, the reductions appear to be trivial, even small reductions in systolic BP (for example, 3-5 mm Hg) produce dramatic reduction in adverse cardiac events and stroke. On the basis of the results of clinical and clinical/observational studies, it has been recommended that more emphasis be placed on lifestyle/behavior modification (obesity, high dietary intake of fat and sodium, physical inactivity, smoking, excessive alcohol intake, low dietary potassium intake) to control BP and also to improve the efficacy of pharmacologic treatment of high BP. New classes of antihypertensive drugs and new compounds in the established drug classes are likely to widen the armamentarium available to combat hypertension. These include the aldosterone receptor blockers, vasodilator beta-blockers, renin inhibitors, endothelin receptor antagonists, and dual endopeptidase inhibitors. The use of fixed-dose combination drug therapy is likely to increase. There is a conceptual possibility that gene therapy may yield long-lasting antihypertensive effects by influencing the genes associated with hypertension. But, the treatment of human essential hypertension requires sustained over-expression of genes. Some of the challenging tasks for successful gene therapy that need to be mastered include identification of target genes, ideal gene transfer vector, precise delivery of genes into the required site (target), efficient transfer of genes into the cells of the target, and prompt assessment of gene expression over time. Targeting the RAS by antisense gene therapy appears to be a viable strategy for the long-term control of hypertension. Several problems that are encountered in the delivery of gene therapy include 1) low efficiency for gene transfer into vascular cells; 2) a lack of selectivity; 3) problem in determining how to prolong and control transgene expression or antisense inhibition; and 4) difficulty in minimizing the adverse effects of viral or nonviral vectors. In spite of the hurdles that face gene therapy administration in humans, studies in animals indicate that gene therapy may be feasible in treating human hypertension, albeit not in the near future. DNA testing for genetic polymorphism and determining the genotype of a patient may predict response to a certain class of antihypertensive agent and thus optimize therapy in individual patients. In this regard, there are some studies that report the effectiveness of antihypertensive therapy based upon the genotype of selected patients. Treatment of human hypertension with vaccines is feasible but is not likely to be available in the near future.

Combination ACE Inhibitor and Angiotensin Receptor Blocker Therapy-Future Considerations

Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers are regularly prescribed for the management of hypertension. Each of these drug classes has also been shown to provide survival benefits for patients with heart failure, proteinuric chronic kidney disease, and/or a high cardiac risk profile. The individual gains seen with each of these drug classes have led to speculation that their combination might offer additive if not synergistic outcome benefits. The foundation of this hypothesis, although biologically possible, has thus far not been sufficiently well proven to support the everyday use of these 2 drug classes in combination. Additional outcomes trials, which are currently proceeding to their conclusion, may provide the necessary proof to support an expanded use of these 2 drug classes in combination.

Rational design of a selective antagonist of epsilon protein kinase C derived from the selective allosteric agonist, pseudo-RACK peptide

We have previously shown that domains involved in binding of protein kinase C (PKC) isozymes to their respective anchoring proteins (RACKs) and short peptides derived from these domains are PKC isozyme-selective antagonists. We also identified PKC isozyme-selective agonists, named psiRACK peptides, derived from a sequence within each PKC with high homology to its respective RACK. We noted that all the psiRACK sequences within each PKC isozyme have at least one non-homologous amino acid difference from their corresponding RACK that constitutes a charge change. Based on this information, we have devised here a new approach to design an isozyme-selective PKC antagonist, derived from the psiRACK sequence. We focused on epsilonPKC psiRACK peptide, where the pseudo-epsilonRACK sequence (psiepsilonRACK; HDAPIGYD; corresponding to epsilonPKC85-92) is different in charge from the homologous RACK-derived sequence (NNVALGYD; corresponding to epsilonRACK285-292) in the second amino acid. Here we show that changing the charge of the psiepsilonRACK peptide through a substitution of only one amino acid (aspartate to asparagine) resulted in a peptide with an opposite activity on the same cell function and a substitution for aspartate with an alanine resulted in an inactive peptide. These data support our hypothesis regarding the mechanism by which pseudo-RACK peptide activates PKC in heart cells and suggest that this approach is applicable to other signaling proteins with inducible protein-protein interactions.

Combination Therapy With an Angiotensin Receptor Blocker and an ACE Inhibitor in Proteinuric Renal Disease: A Systematic Review of the Efficacy and Safety Data

Blockade of the renin-angiotensin system with either an angiotensin-converting enzyme (ACE) inhibitor or an angiotensin receptor blocker (ARB) was shown to decrease urinary protein excretion and slow the progression of both diabetic and nondiabetic proteinuric renal disease. The safety and efficacy of combined ACE-inhibitor and ARB therapy is not well established. We conducted a systematic review and meta-analysis of randomized trials evaluating the combination of an ACE inhibitor and an ARB in patients with chronic proteinuric renal disease. Twenty-one randomized controlled studies (n = 654 patients) were identified using MEDLINE, EMBASE, and Cochrane Central databases. Five trials had a parallel-group design and 16 trials used a crossover design. Combination therapy with an ACE inhibitor and an ARB resulted in a small, but significant, increase in serum potassium levels (weighted mean difference, 0.11 mEq/L [0.11 mmol/L]; 95% confidence interval [CI], 0.05 to 0.17) and a nonsignificant decrease in glomerular filtration rate (weighted mean difference, 1.4 mL/min [0.02 mL/s]; 95% CI, -2.6 to 0.2). Addition of an ARB resulted in a further decrease in proteinuria (weighted mean difference, 440 mg/d; 95% CI, 289 to 591) compared with an ACE inhibitor alone. This effect was observed in patients with diabetic (210 mg/d; 95% CI, 84 to 336) and nondiabetic (582 mg/d; 95% CI, 371 to 793) renal disease. In conclusion, the combination of ACE-inhibitor and ARB therapy in patients with chronic proteinuric renal disease is safe, without clinically meaningful changes in serum potassium levels or glomerular filtration rates. Combination therapy also was associated with a significant decrease in proteinuria, at least in the short term. Additional trials with longer follow-up are needed to determine whether the decrease in proteinuria will result in significant preservation of renal function.

Long-Term Renoprotective Effects of Standard Versus High Doses of Telmisartan in Hypertensive Nondiabetic Nephropathies

BACKGROUND

This report describes an open randomized study intended to evaluate the long-term renoprotective effects of "standard" (80 mg once daily) versus "high" (80 mg twice daily) doses of telmisartan in hypertensive patients without diabetes with biopsy-proven chronic proteinuric nephropathies.

METHODS

We included 78 patients (age, 43.5 +/- 13.2 years; 71.8% men). After a 4-week wash-out period, patients were randomly assigned to telmisartan, 80 mg once daily (n = 40) or 80 mg twice daily (n = 38), during a mean follow-up of 24.6 +/- 2.2 months.

RESULTS

Baseline characteristics were similar in both groups, including blood pressure, renal function, and proteinuria. Blood pressure control did not differ between groups during follow-up. In the group administered telmisartan, 80 mg once daily, serum creatinine level increased from 1.6 +/- 0.6 to 2.7 +/- 0.9 mg/dL (141 +/- 52 to 239 +/- 80 micromol/L), and estimated creatinine clearance declined from 68 +/- 30 to 50 +/- 34 mL/min (1.13 +/- 0.50 to 0.83 +/- 0.57 mL/s), whereas in those administered 80 mg twice daily, serum creatinine (1.6 +/- 0.7 to 1.6 +/- 0.8 mg/dL [141 +/- 62 to 141 +/- 71 micromol/L]) and estimated creatinine clearance values (67 +/- 38 to 74 +/- 38 mL/min [1.12 +/- 0.63 to 1.23 +/- 0.63 mL/s]) did not change during the study. The decrease in proteinuria was more pronounced (P < 0.01) in patients administered the high dose of telmisartan compared with those treated with the standard dose. Serum potassium levels and lipid profiles did not change significantly in either group.

CONCLUSION

Long-term administration of high doses of telmisartan seems to improve the efficacy of the drug to decrease proteinuria and slow the progression to end-stage renal failure in nondiabetic hypertensive renal disease.

Primary and secondary prevention of chronic kidney disease

The incidence and prevalence of chronic kidney disease (CKD) is on the rise worldwide. End-stage renal disease (ESRD) is the most advanced form of CKD, requiring some form of renal replacement therapy to ensure survival. Interventions to prevent or slow the progression of CKD, irrespective of the original cause, are thus of significant importance. The most effective of these interventions is based on the inhibition of the renin-angiotensin system (RAS) and is the main focus of this review.

Valsartan: the past, present and future

Valsartan (Diovan) is a widely use angiotensin receptor blocker that prevents angiotensin II from binding to the subtype 1 receptor. Stimulation of the subtype 1 receptor is believed to mediate many of the deleterious effects accompanied by increased angiotensin II levels. Valsartan is effective in the treatment of hypertension, alone and in combination with hydrochlorothiazide. Valsartan is similarly as effective as angiotensin-converting enzyme (ACE) blockers following myocardial infarction accompanied with left ventricular dysfunction, and/or heart failure. For the treatment of congestive heart failure with left ventricular dysfunction, valsartan offers a reduction in mortality in patients not able to tolerate an ACE inhibitor and in combination with an ACE inhibitor, valsartan reduces morbidity (hospitalization for heart failure).

Minor abnormalities of renal function: a situation requiring integrated management of cardiovascular risk

Changes in renal function related with essential hypertension are associated with an elevated cardiovascular morbidity and mortality. Indices of altered renal function (e.g. microalbuminuria, increased serum creatinine concentrations, decrease in estimated creatinine clearance or overt proteinuria) are independent predictors of cardiovascular morbidity and mortality. The Framingham Heart Study documented the relevance of proteinuria for cardiovascular prognosis in the community. The Intervention as a Goal in Hypertension Treatment (INSIGHT) Study assessed the role of proteinuria as a very powerful risk factor. It has also been shown that microalbuminuria along with primary hypertension poses a high risk for cardiovascular diseases. Recent data indicate that even minor derangements of renal function are associated with the clustering of cardiovascular risk factors observed in metabolic syndrome, that promote progression of atherosclerosis. All these parameters should be routinely evaluated in clinical practice, and considered in any stratification of cardiovascular risk in hypertensive patients. The high prevalence of chronic kidney disease in the general and in the hypertensive populations implies the need for an integrative therapeutic approach to fully protect renal and cardiovascular systems simultaneously.

Strategies to retard the progression of chronic kidney disease

Chronic kidney disease (CKD) is a common and, in advanced cases, highly morbid disorder. The most severe form of CKD is end-stage renal disease (ESRD), in which the patient requires some form of renal replacement therapy to survive. The increasing incidence, prevalence, and costs of ESRD are major national health care concerns; interventions that may prevent or slow the progression of CKD towards ESRD are extremely important and the focus of this article.

Diuretic and Enhanced Sodium Restriction Results in Improved Antiproteinuric Response to RAS Blocking Agents

Angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and diuretics may exert synergistic antiproteinuric effects. Eighteen patients with a proteinuria >1 g/24 h after 6 mo of treatment with ramipril at 5 mg/d were assigned to receive in random order ramipril at 10 mg/d, valsartan at 160 mg/d, or combined ramipril at 5 mg/d and valsartan at 80 mg/d in addition to their antihypertensive treatment. The treatment periods lasted 4 wk and were separated by a 4-wk washout with ramipril at 5 mg/d. At the end of this crossover sequence, patients received combined ramipril at 5 mg/d, valsartan at 80 mg/d, and an increased furosemide dosage for an additional 4-wk period. The primary end point was the urinary protein/creatinine ratio for two 24-h urine collections at the end of each treatment period. No significant differences were noted between the study end points of the ramipril 10, valsartan 160, and combined ramipril 5 and valsartan 80 treatment groups. However, the urinary protein/creatinine ratio was lower with combined ramipril 5 and valsartan 80-increased furosemide dosage than with valsartan 160 and combined ramipril 5 and valsartan 80, with a similar tendency compared with ramipril 10. Combined ramipril 5 and valsartan 80-increased furosemide dosage decreased systolic home BP and increased serum creatinine but did not significantly increase the number of symptomatic hypotension cases compared with the other three treatments. Thus, in patients with severe proteinuria and hypertension, a cautious increase in diuretic dosage in addition to combined angiotensin-converting enzyme inhibitors and angiotensin receptor blockers decreases proteinuria and BP but may expose the patient to prerenal failure.

How to titrate ACE inhibitors and angiotensin receptor blockers in renal patients: according to blood pressure or proteinuria?

The inhibition of the effects of angiotensin II is necessary to ensure the best degree of renal protection by the simultaneous control of blood pressure (BP) and the achievement of the maximal antiproteinuric capacity. The inhibition can be attained through the administration of either an angiotensin-converting enzyme (ACE) inhibitor or an angiotensin II receptor blocker (ARB). Uptitration of antihypertensive therapy is frequently required to achieve the desired BP goal in patients presenting with renal disease, with or without proteinuria. Control of BP is good for both cardiovascular and renal protection. Sometimes, in particular when BP levels are high in the absence of therapy, the simple control of BP without inhibiting the renin- angiotensin system can be accompanied by a significant drop in proteinuria. On the other hand, the possibility that an ACE inhibitor or an ARB diminishes protein excretion in urine in the absence of changes in BP has been considered after the known evidence that these classes of drugs are renoprotective independently of their effect on BP control. The aim of this paper is to briefly review the evidence in favor of uptitration of either class of inhibitors of the renin-angiotensin system as compared with the combination of the two for the control of either BP or proteinuria.