Dual Blockade of the Renin-Angiotensin System in the Progression of Renal Disease: The Need for More Clinical Trials

Dual renin-angiotensin-aldosterone blockade: Implementation of published research and Dear Doctor letters in ambulatory care: A retrospective observational study using prescription data

PURPOSE

This study aims to assess the implementation of published research, contraindications, and warnings on the prescription of dual renin-angiotensin-hormone system (RAS) blockade in ambulatory care in Germany.

METHODS

Cohort study based on health claims data of 6.7 million subjects from 2008 to 2015. Yearly prevalence and incidence for dual RAS blockade with (a) angiotensin-converting enzyme inhibitors and angiotensin-receptor blockers (ACEI + ARB) and (b) aliskiren and ACEI or ARB (aliskiren + ACEI/ARB) were calculated. We assessed prescriber specialty and associations between discontinuing dual RAS blockade with specialist (internal medicine, cardiology, nephrology) visits and hospital discharge in the previous year.

RESULTS

A total of 2 984 517 patients were included (age 51.4 ± SD 18.4 y, 48.5% male). Prescription rates for ACEI + ARB decreased from 0.6% (n = 17 907) to 0.4% (n = 12 237) and for aliskiren + ACEI/ARB from 0.23% (n = 6634) to 0.03% (n = 818). Incident prescriptions decreased from 0.23% (n = 6705) to 0.19% (n = 5055) (ACE + ARB) and from 0.1% (n = 2796) to 0.005% (n = 142) (aliskiren + ACE/ARB); 59% of ACEI + ARB and 48% of aliskiren + ACE/ARB combinations were prescribed only by one physician. Of those, 73% (ACEI + ARB) and 58% (aliskiren + ACE/ARB) were primary care providers (PCPs). Discontinuing dual RAS blockade was associated with specialist care and hospital discharge in the previous year (specialist care: RR 1.4, 95% CI, 1.3-1.6; hospital visit: RR 1.5, 95% CI, 1.3-1.6).

CONCLUSIONS

Our results suggest a delayed uptake of treatment recommendation for ACEI + ARB and a higher impact of Dear Doctor letters addressing PCPs directly compared with published research, contraindications, and warnings. Targeted continuous medical education, practice software alerts, and stronger involvement of pharmacists might improve the implementation of medication safety recommendations in ambulatory care.

Clinical study on Yishen Qufeng Shengshi Recipe () for glomerular proteinuria patients: A randomized controlled trial

OBJECTIVE

To explore the therapeutic effect of Yishen Qufeng Shengshi Recipe (, YQSR) in patients with glomerular proteinuria METHODS: A total of 145 patients with glomerular proteinuria were selected and randomly assigned to the treatment group (108 cases) and the control group (37 cases) according to a random number table in a ratio of 3:1. All patients received conventional and symptomatic treatment. In addition, patients in the treatment and control groups were given YQSR (200 mL, twice per day, orally) and losartan (50 mg/d orally), respectively for 6 months. The 24-h urine protein quantity, blood urea nitrogen, and serum creatinine in the two groups were measured at multiple time points before and after treatment.

RESULTS

At the end of the study, 5 cases were lost to follow-up in the treatment group and 1 in the control group. Finally, the statistical data included 103 cases in the treatment group and 36 cases in the control group. The total effectiveness after 2, 4, and 6 months was 81.6% (84/103), 87.4% (90/103), and 92.2% (95/103), respectively, in the treatment group and 47.2% (17/36), 55.6% (20/36), and 61.1% (22/36), respectively, in the control group, with significant difference between the two groups (P<0.01 at all observation points). In the treatment group, the curative effect after 6 months was better than that after 2 months (P<0.05). The 24-h urine protein quantity was significantly lower in the treatment group at 3, 4, 5, and 6 months than that in the control group (P<0.05 or P<0.01, respectively) CONCLUSION: YQSR could significantly reduce the amount of glomerular proteinuria in the early stage.

Renin-angiotensin-aldosterone system blockade in chronic kidney disease: current strategies and a look ahead

The Renin-Angiotensin-Aldosterone System (RAAS) is profoundly involved in the pathogenesis of renal and cardiovascular organ damage, and has been the preferred therapeutic target for renal protection for over 30 years. Monotherapy with either an Angiotensin Converting Enzime Inhibitor (ACE-I) or an Angiotensin Receptor Blocker (ARB), together with optimal blood pressure control, remains the mainstay treatment for retarding the progression toward end-stage renal disease. Combining ACE-Is and ARBs, or either one with an Aldosterone Receptor Antagonist (ARA), has been shown to provide greater albuminuria reduction, and to possibly improve renal outcome, but at an increased risk of potentially severe side effects. Moreover, combination therapy has failed to provide additional cardiovascular protection, and large prospective trials on hard renal endpoints are lacking. Therefore this treatment should, at present, be limited to selected patients with residual proteinuria and high renal risk. Future studies with novel agents, which directly act on the RAAS at multiple levels or have a more favourable side effect profile, are greatly needed to further explore and define the potential for and the limitations of profound pharmacologic RAAS inhibition.

Combination use of medicines from two classes of renin-angiotensin system blocking agents: risk of hyperkalemia, hypotension, and impaired renal function

European and United States regulatory agencies recently issued warnings against the use of dual renin-angiotensin system (RAS) blockade therapy through the combined use of angiotensin-converting enzyme inhibitors (ACEIs), angiotensin II receptor blockers (ARBs) or aliskiren in any patient, based on absence of benefit for most patients and increased risk of hyperkalemia, hypotension, and renal failure. Special emphasis was made not to use these combinations in patients with diabetic nephropathy. The door was left open to therapy individualization, especially for patients with heart failure, when the combined use of an ARB and ACEI is considered absolutely essential, although renal function, electrolytes and blood pressure should be closely monitored. Mineralocorticoid receptor antagonists were not affected by this warning despite increased risk of hyperkalemia. We now critically review the risks associated with dual RAS blockade and answer the following questions: What safety issues are associated with dual RAS blockade? Can the safety record of dual RAS blockade be improved? Is it worth trying to improve the safety record of dual RAS blockade based on the potential benefits of the combination? Is dual RAS blockade dead? What is the role of mineralocorticoid antagonists in combination with other RAS blocking agents: RAAS blockade?

Efficacy and safety of Shenyankangfu tablets for primary glomerulonephritis: study protocol for a randomized controlled trial

BACKGROUND

Chronic kidney disease is a common disease. Most chronic kidney diseases evolve from primary glomerulonephritis. Proteinuria is an independent risk factor for the progression of chronic kidney disease. The general consensus is that therapy administered to decrease proteinuria should include steroids and/or immunosuppressants, angiotensin-converting enzyme inhibitors, and angiotensin II receptor blockers. However, the side effects of, and adverse reactions to, these agents reduce the benefits to patients. In addition, the cost of these drugs is relatively high. Therefore, identification of inexpensive and effective drugs to decrease proteinuria is urgently needed. Shenyankangfu tablets have been a widely applied Chinese patent medicine for many years to decrease proteinuria. However, there is a lack of research-derived data regarding the clinical use. Therefore, we designed the present randomized controlled clinical trial to compare the efficacy and safety of Shenyankangfu tablets versus losartan potassium for control of proteinuria in patients with primary glomerulonephritis.

METHODS/DESIGN

This study will be a multicenter, prospective, double-blind, double-dummy, randomized controlled clinical trial. We will enroll 720 patients diagnosed with primary glomerulonephritis. The eligible patients will be randomly divided into the following groups at a 1:1:1:1:1 ratio: Shenyankangfu tablets group, losartan potassium 50 mg group, losartan potassium 100 mg group, Shenyankangfu tablets + losartan potassium 50 mg group, and Shenyankangfu tablets + losartan potassium 100 mg group. All groups will be followed up for 48 weeks; follow-up visits will be performed, at weeks 0, 4, 8, 12, 24, 36, and 48. The primary efficacy outcome will be the post-treatment change in the 24-hour proteinuria level, and the secondary efficacy outcomes will be the post-treatment changes in the serum creatinine level, estimated glomerular filtration rate, traditional Chinese medicine syndrome score, and serum albumin level.

DISCUSSION

The results of this trial will provide solid data for use in evidence-based medicine with respect to the efficacy and safety of Shenyankangfu tablets for control of proteinuria in patients with primary glomerulonephritis compared to those of losartan potassium. Moreover, we infer that therapy comprising Shenyankangfu tablets + losartan potassium can decrease proteinuria to a larger extent than Shenyankangfu tablets or losartan potassium can alone.

TRIAL REGISTRATION

This trial was registered on 12 February 2014 at ClinicalTrials.gov (ID number NCT02063100).

'Huang Qi Elixir' for proteinuria in patients with diabetic nephropathy: a study protocol for a randomized controlled pilot trial

BACKGROUND

Diabetic nephropathy (DN) is the major complication of diabetes; proteinuria is the hall mark of DN. Currently, the treatment for proteinuria is mainly limited to angiotensin converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs). According to Traditional Chinese Medicine (TCM) theory, Chinese medicinals 'securing essence and tonifying the kidney' may be appropriate for proteinuria. The most promising Chinese medicinals and formulae are introduced in the present study to form a potent formula for DN proteinuria. To make oral administration convenient, the formula will be processed in the form of granules.

METHODS/DESIGN

A randomized, multi-center pilot trial will be conducted. Forty eight participants with DN will be randomly assigned to one of four treatment groups: 1. A granule group, at 10 grams, three times daily (G10 group, n = 12); 2. A granule group, at 20 grams, three times daily (G20 group, n = 12); 3. A decoction group (D group, n = 12); and 4. An irbesartan group (Aprovel group, n = 12).The following outcome measures will be used: the percentage change of the albumin-to-creatinine ratio; and the changes in serum creatinine, glomerular filtration rate, fasting plasma glucose and hemoglobulin from baseline to the end of the trial.

DISCUSSION

It is notable that most published clinical trials which assessed the efficacy of TCM on DN were of poor methodology and, therefore, their results have been invalidated. It is necessary to carry out well-designed clinical trials to provide sound evidence. The present trial is a study with potentially great value, for it will provide the parameters for future randomized, placebo-controlled, clinical trials with large sample sizes.

TRIAL REGISTRATION

The trial is registered on the Chinese Clinical Trial Registry: ChiCTR-TRC-12002718 (http://www.chictr.org/cn/proj/show.aspx?proj=3820).

Additive antiproteinuric effect of enalapril and losartan in children with hemolytic uremic syndrome

BACKGROUND

Angiotensin-converting enzyme inhibitors or angiotensin II type 1 receptor blockers decrease postdiarrheal hemolytic uremic syndrome (D + HUS) sequelar proteinuria. However, proteinuria may persist in some patients. In nephropathies other than D + HUS, an additive antiproteinuric effect with coadministration of both drugs has been observed.

METHODS

To assess such an effect in D + HUS, 17 proteinuric children were retrospectively studied. After a median period of 1 year post-acute stage (range 0.5-1.9) patients received enalapril alone for a median of 2.6 years (range 0.33-12.0) at a median dose of 0.4 mg/kg/day (range 0.2-0.56). As proteinuria persisted, losartan was added at a median dose of 1.0 mg/kg/day (range 0.5-1.5) during 2.1 years (range 0.5-5.0).

RESULTS

The decrease in proteinuria with enalapril was 58.0 %, which was further reduced to 83.8 % from the initial value after losartan introduction. The percentage of reduction was significantly greater with the association of both drugs (p = 0.0006) compared with the effect of enalapril exclusively (p = 0.023). Serum potassium, glomerular filtration rate, and blood pressure remained unchanged.

CONCLUSIONS

Our results suggest that adding losartan to persisting proteinuric D + HUS children already on enalapril is safe and reduces proteinuria more effectively. Whereas this effect is associated with long-term kidney protection, it should be determined by prospective controlled studies.

High-dose enalapril treatment reverses myocardial fibrosis in experimental uremic cardiomyopathy

AIMS

Patients with renal failure develop cardiovascular alterations which contribute to the higher rate of cardiac death. Blockade of the renin angiotensin system ameliorates the development of such changes. It is unclear, however, to what extent ACE-inhibitors can also reverse existing cardiovascular alterations. Therefore, we investigated the effect of high dose enalapril treatment on these alterations.

METHODS

Male Sprague Dawley rats underwent subtotal nephrectomy (SNX, n = 34) or sham operation (sham, n = 39). Eight weeks after surgery, rats were sacrificed or allocated to treatment with either high-dose enalapril, combination of furosemide/dihydralazine or solvent for 4 weeks. Heart and aorta were evaluated using morphometry, stereological techniques and TaqMan PCR.

RESULTS

After 8 and 12 weeks systolic blood pressure, albumin excretion, and left ventricular weight were significantly higher in untreated SNX compared to sham. Twelve weeks after SNX a significantly higher volume density of cardiac interstitial tissue (2.57±0.43% in SNX vs 1.50±0.43% in sham, p<0.05) and a significantly lower capillary length density (4532±355 mm/mm(3) in SNX vs 5023±624 mm/mm(3) in sham, p<0.05) were found. Treatment of SNX with enalapril from week 8-12 significantly improved myocardial fibrosis (1.63±0.25%, p<0.05), but not capillary reduction (3908±486 mm/mm(3)) or increased intercapillary distance. In contrast, alternative antihypertensive treatment showed no such effect. Significantly increased media thickness together with decreased vascular smooth muscles cell number and a disarray of elastic fibres were found in the aorta of SNX animals compared to sham. Both antihypertensive treatments failed to cause complete regression of these alterations.

CONCLUSIONS

The study indicates that high dose ACE-I treatment causes partial, but not complete, reversal of cardiovascular changes in SNX.

Have the renin-angiotensin-aldosterone system perturbations in cardiovascular disease been exhausted?

The renin-angiotensin-aldosterone system (RAAS) plays an important role in blood pressure control and volume homeostasis. Inappropriate activation of the RAAS has been implicated in the pathogenesis of hypertension and related cardiovascular disease. Several classes of agents that block RAAS signaling have been shown to be effective antihypertensives and to have cardioprotective and renoprotective properties. Because blockade of the RAAS is incomplete with any of the currently available monotherapies, combinations of these agents have been tested and shown to provide additional clinical benefit in patients with hypertension and various forms of cardiovascular and renal disease.

Effects of telmisartan and enalapril on renoprotection in patients with mild to moderate chronic kidney disease

BACKGROUND

Blocking the renin-angiotensin system (RAS) with angiotensin receptor blockers or angiotensin-converting enzyme inhibitors protects against renal injury in patients with chronic kidney disease (CKD). The aim of this study was to compare the chronic effects of telmisartan and enalapril on proteinuria, urinary liver-type fatty acid-binding protein (L-FABP) and endothelin (ET)-1 levels in patients with mild CKD.

MATERIALS AND METHODS

Thirty CKD patients with mild to moderate renal insufficiency (20 men and 10 women; mean age, 37 years; estimated glomerular filtration rate (eGFR) > 60 mL min(-1) and blood pressure > 130/85 mmHg) were included in the study. Patients were randomly assigned to receive telmisartan at 80 mg day(-1) (n = 15) or enalapril at 10 mg day(-1) (n = 15). We measured blood pressure, serum creatinine, eGFR, urinary protein, L-FABP and ET-1 before the start of treatment and 6 and 12 months after the start of treatment.

RESULTS

The blood pressure reduction rate was similar between the two groups. Urinary protein, L-FABP and ET-1 levels were significantly reduced in both groups 6 and 12 months (P < 0.001) after treatment, but the reduction rates were more pronounced in patients receiving telmisartan than in those receiving enalapril (P < 0.001). Estimated glomerular filtration rate was increased similarly in both groups at 12 months.

CONCLUSIONS

The study results suggest that telmisartan results in a greater reduction of urinary markers than does enalapril and that this effect occurs by a mechanism independent of blood pressure reduction. It would be needed to investigate whether the differences may be distinct or not the same when other dosages are used.

Valsartan in combination with lisinopril versus the respective high dose monotherapies in hypertensive patients with microalbuminuria: the VALERIA trial

OBJECTIVES

Microalbuminuria is known as an independent predictor for stroke, myocardial infarction, and death. The purpose of the VALERIA trial was a comparison of the efficacy and safety of combination therapy of valsartan and lisinopril with valsartan and lisinopril high-dose monotherapy in patients with hypertension and microalbuminuria.

METHODS

This was a randomized, double-blind, interventional, parallel-group study. After a washout/placebo-run-in phase of 3 weeks, 133 patients were randomized to treatment (1: 1:1) with either lisinopril 40 mg, valsartan 320 mg, or a combination of valsartan/lisinopril 320/20 mg for 30 weeks.

RESULTS

At baseline, the urine albumin creatinine ratio was similar for the three treatment groups (geometric means, lisinopril 9.6 mg/mmol, valsartan 9.1 mg/mmol, and valsartan/lisinopril 9.5 mg/mmol). After 30 weeks of treatment, the geometric mean urine albumin creatinine ratio had decreased in all three groups by 41, 51, and 62% to 5.7 mg/mmol (lisinopril), 4.5 mg/mmol (valsartan), and 3.6 mg/mmol (valsartan/lisinopril). The decrease for valsartan/lisinopril was statistically significantly greater compared with lisinopril [adjusted ratio 60%, confidence interval (38-94%), P = 0.029]. Normalization of microalbuminuria was greatest with valsartan and valsartan/lisinopril (lisinopril 17%, valsartan 31%, and valsartan/lisinopril 38% of patients) and was statistically significant for lisinopril in contrast with valsartan/lisinopril (P = 0.034). Differences in blood pressure reduction between the groups were not statistically significant. All treatments were safe and well tolerated.

CONCLUSION

The combination of valsartan and lisinopril provided a significantly better reduction of urine albumin creatinine ratio and more than doubled the rate of patients with normalized urine albumin creatinine ratio compared with lisinopril alone. All treatments were safe and well tolerated.

Renal effects of dual renin-angiotensin-aldosterone system blockade in patients with diabetic nephropathy

Evidence from recent studies indicates that in patients with diabetic nephropathy combined therapy with ACE inhibitors (ACEI) and AT1-receptor antagonists (ARB) results in more complete blockade of the renin-angiotensin-aldosterone system (RAS) than monotherapy, and reduces proteinuria. Most of these trials, however, had short follow-up, included a small number of patients, and were heterogeneous, so the opportunity to start this treatment in these patients remains unclear. This review summarizes the results of these studies, describing the renal effects of dual RAS blockade in both type 1 and type 2 diabetic patients.

Current possibilities of ACE inhibitor and ARB combination in arterial hypertension and its complications

The renin-angiotensin-aldosterone system (RAAS) plays a crucial role in blood pressure regulation and hypertension-related complications. Angiotensin-converting enzyme inhibitors (ACEIs) were the first to be used to block the RAAS and now have many compelling indications in the treatment of hypertension and its cardiovascular and renal complications. Angiotensin II receptor blockers (ARBs), introduced 20 years later, have been shown to be equally as effective as antihypertensive treatment and are also associated with a lower number of side effects. Furthermore, in clinical trials ARBs and ACEIs were associated with comparable benefits for their most typical indications. This was confirmed in the 2007 New European Society of Hypertension/European Society of Cardiology (ESH/ESC) guidelines for the management of hypertension by comparable specific recommendations for ARB and ACEI treatment. There is sufficient theoretical background and, in some cases, also clinical evidence that combination therapy with ACEIs and ARBs may be more beneficial than monotherapy with either of the groups alone, both in uncomplicated hypertension and with concomitant heart failure or renal dysfunction. However, the combination of ACEI and ARB was not recommended in the ESH/ESC 2007 Guidelines. This may change after the publication of the Ongoing Telmisartan Alone and in Combination with Ramipril Global End point Trial (ONTARGET) study, the preliminary results of which have just been presented. In heart failure, recent studies have shown that the combination of ACEI and ARB decreases cardiovascular mortality and the number of hospitalizations due to aggravation of heart failure. These results have been reflected in the newest ESC guidelines of the heart failure treatment. Nephroprotective properties of the combination of ACEs and ARBs have been proved both in studies on nondiabetic and diabetic nephropathy. The potential benefits, indications in prespecified groups of patients, the most recent data from clinical trials and latest research regarding dual blockade of RAAS will be reviewed in this article.

Improving outcomes in diabetes and chronic kidney disease: the basis for Canadian guidelines

The prevalence of diabetes is on the rise in Canada, and there has been a corresponding increase in the rate of micro- and macrovascular complications. Among the worst of these is chronic kidney disease (CKD). It may be diagnosed either through the detection of persistent albuminuria or an estimated glomerular filtration rate that is persistently less than 60 mL/min/1.73 m2. Patients with diabetes and CKD have a lower quality of life and higher health care costs, and face the prospect of end-stage renal disease requiring dialysis. More importantly, this group has an extremely elevated cardiovascular risk and correspondingly reduced survival. Research over several decades has led to two important conclusions. First, progressive worsening of kidney disease is not inevitable in people with diabetes; it can be slowed or even stopped. Second, the elevated cardiovascular risk in this population can be significantly reduced through an aggressive approach to cardiovascular risk factor reduction. These conclusions have prompted Canadian guideline groups, such as the Canadian Diabetes Association and the Canadian Hypertension Education Program, to release clinical practice guidelines that address the management of people with diabetes and CKD. In the present article, the studies that have influenced these Canadian guidelines are examined, and areas in which further research is still required are identified.