Prevention of microalbuminuria in patients with type 2 diabetes and hypertension

Inter-relationships between cardiovascular, renal and metabolic diseases: Underlying evidence and implications for integrated interdisciplinary care and management

Cardiovascular, renal and metabolic (CaReMe) diseases are individually among the leading global causes of death, and each is associated with substantial morbidity and mortality. However, as these conditions commonly coexist in the same patient, the individual risk of mortality and morbidity is further compounded, leading to a considerable healthcare burden. A number of pathophysiological pathways are common to diseases of the CaReMe spectrum, including neurohormonal dysfunction, visceral adiposity and insulin resistance, oxidative stress and systemic inflammation. Because of the shared pathology and common co-occurrence of the CaReMe diseases, the value of managing these conditions holistically is increasingly being realized. A number of pharmacological and non-pharmacological approaches have been shown to offer simultaneous metabolic, cardioprotective and renoprotective benefits, leading to improved patient outcomes across the CaReMe spectrum. In addition, increasing value is being placed on interdisciplinary team-based and coordinated care models built on greater integration between specialties to increase the rate of early diagnosis and adherence to practice guidelines, and improve clinical outcomes. This interdisciplinary approach also facilitates integration between primary and specialty care, improving the patient experience, optimizing resources, and leading to efficiencies and cost savings. As the burden of CaReMe diseases continues to increase, implementation of innovative and integrated care delivery models will be essential to achieve effective and efficient chronic disease management and to ensure that patients benefit from the best care available across all three disciplines.

Effects of angiotensin II receptor blockers on serum potassium level and hyperkalemia risk: retrospective single-centre analysis

OBJECTIVE

To examine the effect of angiotensin II receptor blocker (ARB) treatment on serum potassium level and hyperkalaemia risk in a clinical setting with inpatients and outpatients using calcium channel blockers (CCBs) as a reference standard.

METHODS

The increased risk of hyperkalaemia associated with ARB treatment is known, however only a few studies have used an active comparator to examine this risk. In this retrospective study at a 320-bed general hospital in Japan, the hospital information system was used to identify patients with at least one prescription for an ARB (819 patients) or a CCB (1015 patients) who were naive to these drugs before study initiation. Serum potassium levels before and after ARB treatment were compared. Additionally, the unadjusted and adjusted hazard ratios for the risk of hyperkalaemia in the ARB and CCB users were estimated.

RESULTS

The serum potassium level was higher in patients receiving ARB treatment (0.05 mEq/L, p=0.02) compared with those on CCB treatment. However, there was no significant association between ARB use and hyperkalaemia (adjusted HR 0.91, 95% CI 0.42 to 1.99, p=0.82).

CONCLUSION

The increase in serum potassium level after ARB initiation makes it necessary to monitor serum potassium levels continuously during ARB treatment; however, the risk of hyperkalaemia appeared to be similar for ARB and CCB treatments.

Blood pressure control for diabetic retinopathy

BACKGROUND

Diabetic retinopathy is a common complication of diabetes and a leading cause of visual impairment and blindness. Research has established the importance of blood glucose control to prevent development and progression of the ocular complications of diabetes. Concurrent blood pressure control has been advocated for this purpose, but individual studies have reported varying conclusions regarding the effects of this intervention.

OBJECTIVES

To summarize the existing evidence regarding the effect of interventions to control blood pressure levels among diabetics on incidence and progression of diabetic retinopathy, preservation of visual acuity, adverse events, quality of life, and costs.

SEARCH METHODS

We searched several electronic databases, including CENTRAL, and trial registries. We last searched the electronic databases on 3 September 2021. We also reviewed the reference lists of review articles and trial reports selected for inclusion.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) in which either type 1 or type 2 diabetic participants, with or without hypertension, were assigned randomly to more intense versus less intense blood pressure control; to blood pressure control versus usual care or no intervention on blood pressure (placebo); or to one class of antihypertensive medication versus another or placebo.

DATA COLLECTION AND ANALYSIS

Pairs of review authors independently reviewed the titles and abstracts of records identified by the electronic and manual searches and the full-text reports of any records identified as potentially relevant. The included trials were independently assessed for risk of bias with respect to outcomes reported in this review.

MAIN RESULTS

We included 29 RCTs conducted in North America, Europe, Australia, Asia, Africa, and the Middle East that had enrolled a total of 4620 type 1 and 22,565 type 2 diabetic participants (sample sizes from 16 to 4477 participants). In all 7 RCTs for normotensive type 1 diabetic participants, 8 of 12 RCTs with normotensive type 2 diabetic participants, and 5 of 10 RCTs with hypertensive type 2 diabetic participants, one group was assigned to one or more antihypertensive agents and the control group to placebo. In the remaining 4 RCTs for normotensive participants with type 2 diabetes and 5 RCTs for hypertensive type 2 diabetic participants, methods of intense blood pressure control were compared to usual care. Eight trials were sponsored entirely and 10 trials partially by pharmaceutical companies; nine studies received support from other sources; and two studies did not report funding source. Study designs, populations, interventions, lengths of follow-up (range less than one year to nine years), and blood pressure targets varied among the included trials. For primary review outcomes after five years of treatment and follow-up, one of the seven trials for type 1 diabetics reported incidence of retinopathy and one trial reported progression of retinopathy; one trial reported a combined outcome of incidence and progression (as defined by study authors). Among normotensive type 2 diabetics, four of 12 trials reported incidence of diabetic retinopathy and two trials reported progression of retinopathy; two trials reported combined incidence and progression. Among hypertensive type 2 diabetics, six of the 10 trials reported incidence of diabetic retinopathy and two trials reported progression of retinopathy; five of the 10 trials reported combined incidence and progression. The evidence supports an overall benefit of more intensive blood pressure intervention for five-year incidence of diabetic retinopathy (11 studies; 4940 participants; risk ratio (RR) 0.82, 95% confidence interval (CI) 0.73 to 0.92; I2 = 15%; moderate certainty evidence) and the combined outcome of incidence and progression (8 studies; 6212 participants; RR 0.78, 95% CI 0.68 to 0.89; I2 = 42%; low certainty evidence). The available evidence did not support a benefit regarding five-year progression of diabetic retinopathy (5 studies; 5144 participants; RR 0.94, 95% CI 0.78 to 1.12; I2 = 57%; moderate certainty evidence), incidence of proliferative diabetic retinopathy, clinically significant macular edema, or vitreous hemorrhage (9 studies; 8237 participants; RR 0.92, 95% CI 0.82 to 1.04; I2 = 31%; low certainty evidence), or loss of 3 or more lines on a visual acuity chart with a logMAR scale (2 studies; 2326 participants; RR 1.15, 95% CI 0.63 to 2.08; I2 = 90%; very low certainty evidence). Hypertensive type 2 diabetic participants realized more benefit from intense blood pressure control for three of the four outcomes concerning incidence and progression of diabetic retinopathy. The adverse event reported most often (13 of 29 trials) was death, yielding an estimated RR 0.87 (95% CI 0.76 to 1.00; 13 studies; 13,979 participants; I2 = 0%; moderate certainty evidence). Hypotension was reported in two trials, with an RR of 2.04 (95% CI 1.63 to 2.55; 2 studies; 3323 participants; I2 = 37%; low certainty evidence), indicating an excess of hypotensive events among participants assigned to more intervention on blood pressure.

AUTHORS' CONCLUSIONS

Hypertension is a well-known risk factor for several chronic conditions for which lowering blood pressure has proven to be beneficial. The available evidence supports a modest beneficial effect of intervention to reduce blood pressure with respect to preventing diabetic retinopathy for up to five years, particularly for hypertensive type 2 diabetics. However, there was a paucity of evidence to support such intervention to slow progression of diabetic retinopathy or to affect other outcomes considered in this review among normotensive diabetics. This weakens any conclusion regarding an overall benefit of intervening on blood pressure in diabetic patients without hypertension for the sole purpose of preventing diabetic retinopathy or avoiding the need for treatment for advanced stages of diabetic retinopathy.

Association between antihypertensive treatment and adverse events: systematic review and meta-analysis

OBJECTIVE

To examine the association between antihypertensive treatment and specific adverse events.

DESIGN

Systematic review and meta-analysis.

ELIGIBILITY CRITERIA

Randomised controlled trials of adults receiving antihypertensives compared with placebo or no treatment, more antihypertensive drugs compared with fewer antihypertensive drugs, or higher blood pressure targets compared with lower targets. To avoid small early phase trials, studies were required to have at least 650 patient years of follow-up.

INFORMATION SOURCES

Searches were conducted in Embase, Medline, CENTRAL, and the Science Citation Index databases from inception until 14 April 2020.

MAIN OUTCOME MEASURES

The primary outcome was falls during trial follow-up. Secondary outcomes were acute kidney injury, fractures, gout, hyperkalaemia, hypokalaemia, hypotension, and syncope. Additional outcomes related to death and major cardiovascular events were extracted. Risk of bias was assessed using the Cochrane risk of bias tool, and random effects meta-analysis was used to pool rate ratios, odds ratios, and hazard ratios across studies, allowing for between study heterogeneity (τ2).

RESULTS

Of 15 023 articles screened for inclusion, 58 randomised controlled trials were identified, including 280 638 participants followed up for a median of 3 (interquartile range 2-4) years. Most of the trials (n=40, 69%) had a low risk of bias. Among seven trials reporting data for falls, no evidence was found of an association with antihypertensive treatment (summary risk ratio 1.05, 95% confidence interval 0.89 to 1.24, τ2=0.009). Antihypertensives were associated with an increased risk of acute kidney injury (1.18, 95% confidence interval 1.01 to 1.39, τ2=0.037, n=15), hyperkalaemia (1.89, 1.56 to 2.30, τ2=0.122, n=26), hypotension (1.97, 1.67 to 2.32, τ2=0.132, n=35), and syncope (1.28, 1.03 to 1.59, τ2=0.050, n=16). The heterogeneity between studies assessing acute kidney injury and hyperkalaemia events was reduced when focusing on drugs that affect the renin angiotensin-aldosterone system. Results were robust to sensitivity analyses focusing on adverse events leading to withdrawal from each trial. Antihypertensive treatment was associated with a reduced risk of all cause mortality, cardiovascular death, and stroke, but not of myocardial infarction.

CONCLUSIONS

This meta-analysis found no evidence to suggest that antihypertensive treatment is associated with falls but found evidence of an association with mild (hyperkalaemia, hypotension) and severe adverse events (acute kidney injury, syncope). These data could be used to inform shared decision making between doctors and patients about initiation and continuation of antihypertensive treatment, especially in patients at high risk of harm because of previous adverse events or poor renal function.

REGISTRATION

PROSPERO CRD42018116860.

Influence of pre-treatment blood pressure levels on antihypertensive drug benefits in diabetics: the roadmap experience

Purpose: Most guidelines for treatment of hypertension in the setting of diabetes recommend a blood pressure (BP) target of <130/80 mmHg. However, uncertainty exists about the extent, effectiveness and safety of lowering BP in diabetics. To expand the evidence on this issue, we analysed data from the Randomised Olmesartan and Diabetes MicroAlbuminuria Prevention (ROADMAP) study population.Material: Substudy with blood pressure readings.Methods: The response after initiation of therapy and adequacy of BP control across patients with different BP levels at baseline were analysed.Results: BP at randomisation was 136.2(15.3)/80.6(9.5) [mean (SD)] mmHg with a range of 87-213/37-123 mmHg. At 1 year, mean BP was 127 (11.9)/75 (8.1) mmHg and the overall control rate (<130/80 mmHg) exceeded 61% in this population. The mean reductions in systolic [-9.4 (15.4) mmHg] and diastolic BP [-5.4 (9.5) mmHg] were highly dependent on the BP stage at Visit 1. At 1 year, treatment decreased the prevalence of patients with baseline BP levels of >160/100 from 9 to 2%[[mean BP change -31 (15.7)/ -14 (9.8) mmHg]] and of 140-159/90-99 mmHg from 32 to 11% [[mean BP change -16(12.7)/ -8.9 (8.7) mmHg]], with corresponding increases in the prevalence of patients with baseline BP levels of 120-139/80-99 from 48 to 65% [[mean BP change -4.1 (10.6)/ -3.1 (7.8) mmHg]]and of <120/80 from 11 to 22% [[mean BP change +5.9 (11.8)/+2.5 (8.6) mmHg]]. These effects did not change significantly thereafter and were maintained throughout follow-up.Conclusion: Blood pressure control is feasible in patients with diabetes without nephropathy, independent of baseline BP values. Asymmetric BP-lowering in the first year after starting therapy represents a true antihypertensive effect with sustainable shifts in BP severity.

Bidirectional and Temporal Association Between Hypertension and Microalbuminuria: A Longitudinal Study in Chinese Adults

Background Although hypertension and microalbuminuria are closely interrelated, the magnitude and temporal sequence of the bidirectional association between hypertension and microalbuminuria are largely unknown. We aimed to delineate the bidirectional and temporal relationship between hypertension and microalbuminuria. Methods and Results Leveraging a longitudinal cohort of Chinese adults who had blood pressure and urinary albumin measured twice 4 years apart, we examined the temporal association between hypertension and microalbuminuria by bidirectional and cross-lagged panel analysis. All participants were free of cardiovascular disease and chronic kidney disease at baseline. Bidirectional association analysis found that baseline microalbuminuria predicted the risk of incident hypertension (odds ratio=1.75, P=0.028), and baseline blood pressure also significantly predicted the risk of microalbuminuria (odds ratios=1.27 and 1.21 for a per-SD increase in systolic and diastolic blood pressure, respectively; all P<0.05). Cross-lagged panel analysis demonstrated a bottom-line significant relationship of baseline systolic blood pressure to follow-up urinary albumin ( P=0.079), which is significantly weaker than the other direction of the relationship of baseline urinary albumin to follow-up blood pressures (all P<0.001). Conclusions These findings indicate a significant bidirectional association between microalbuminuria and hypertension in Chinese adults. Elevated urinary albumin excretion is more likely to precede hypertension. The causality between microalbuminuria and hypertension needs further investigation.

Effects of allisartan isoproxil on blood pressure and target organ injury in patients with mild to moderate essential hypertension

Evidence has shown that angiotensin II type 1 receptor antagonists have lower blood pressure and have target organ protective effects, but this is not the case for the drug allisartan isoproxil. The aim of this study was to evaluate the effects of allisartan isoproxil on blood pressure and target organ injury in patients with mild to moderate essential hypertension.In total, 80 essential hypertensive participants were randomly divided into an allisartan group and a nifedipine group (n = 40 per group), and their blood pressure was measured once per month for 6 months. A 2-dimensional echocardiogram was performed at baseline and at the end of the study. The serum levels of renal injury indexes, endothelial function markers, inflammatory factors, blood biochemical assays and urinary measurements were determined at baseline and at 6 months.At the end of the study, both systolic and diastolic blood pressure were significantly decreased in the allisartan group compared with baseline and showed the same antihypertensive effect as the nifedipine group. Meanwhile, the left ventricular remodeling, 24-hours levels of urinary microalbumin, endothelial dysfunction, and arterial stiffness were all significantly improved compared with that of the baseline and the nifedipine group (all P < .05).The present study showed that allisartan isoproxil had favorable blood pressure lowering and heart, renal, and endothelial protective effects in patients with mild to moderate essential hypertension.

Comparison between newly diagnosed hypertension in diabetes and newly diagnosed diabetes in hypertension

BACKGROUND

Hypertension and diabetes mellitus are often jointly present, especially in early onset cases of either disease. We investigated clinical characteristics of hypertensive patients with newly diagnosed diabetes and diabetic patients with newly diagnosed hypertension.

METHODS

Our study subjects were recruited in a China nationwide multicenter registry of hypertension and diabetes (n = 2510). We performed logistic regression to compare patients seen for hypertension in cardiology, with newly diagnosed diabetes (n = 137) and patients seen for diabetes mellitus in endocrinology, with newly diagnosed hypertension (n = 155). Albuminuria was defined as a urinary albumin-to-creatinine ratio of ≥ 30 mg/g, and left ventricular hypertrophy according to the Cornell product index.

RESULTS

These two groups of patients with both hypertension and diabetes mellitus were similar in most of the characteristics (P ≥ 0.06). However, hypertensive patients with newly diagnosed diabetes, compared to diabetic patients with newly diagnosed hypertension, had a significantly greater body mass index (26.3 vs. 25.4 kg/m², P = 0.03) and slower heart rate (73.7 vs. 78.1 beats/min, P = 0.01). In logistic regression analyses adjusted for sex (48.3% women) and age (mean 60.0 ± 11.5 years), the odds ratio for newly diagnosed diabetes mellitus versus newly diagnosed hypertension was 1.27 (95% CI 1.03-1.56) and 0.80 (95% CI 0.66-0.96) for body mass index (+ 3 kg/m²) and heart rate (+ 10 beat/min), respectively. Hypertensive patients with newly diagnosed diabetes also had a lower prevalence of albuminuria (16.0% vs. 30.1%, P = 0.02) and slightly and non-significantly higher prevalence of left ventricular hypertrophy (5.1% vs. 1.9%, P = 0.14) than diabetic patients with newly diagnosed hypertension.

CONCLUSIONS

Earlier or later onset of hypertension than diabetes mellitus may have different risk factors and organ damage.

Comparative Efficacy of Angiotensin II Antagonists in Essential Hypertension: Systematic Review and Network Meta-Analysis of Randomised Controlled Trials

BACKGROUND

Evidence on the long-term clinical benefits of individual members of angiotensin II receptor blockers is limited given the lack of head-to-head studies. We conducted a network meta-analysis to determine the comparative efficacy of different members within this drug class with respect to outcomes of (i) blood pressure reduction (at 24 and 52 weeks) and (ii) prevention of cardiovascular disease (>104 weeks).

METHODS

A systematic literature review was conducted - Protocol registration: (PROSPERO - CRD42014007067) - to identify relevant literature from the following databases: Cochrane Library, PubMed, Medline and EMBASE; searched from inception to July 2016. Randomised controlled trials (RCTs) were included if they reported long-term effectiveness relating to blood pressure, mortality, myocardial infarction or stroke. Eligible studies included those with placebo or specific active-treatment comparators (either another angiotensin II receptor blockers or hydrochlorothiazide). A Bayesian random-effects network model was used to combine direct within-trial comparisons between treatment groups with indirect evidence from other trials.

RESULTS

Thirty-six studies were identified, representing 28 unique trials. Blood pressure reduction, based on 12 studies (n=807) with fixed dosing regimen, was found to be similar amongst members of the angiotensin receptor blocker drug class at both 24 and 52 weeks. A network meta-analysis of five studies (n=16,716) with a treat-to-target approach found that prevention of all-cause mortality, stroke and myocardial infarction was similar across the angiotensin-receptor blockers therapies initiated.

CONCLUSIONS

Current evidence is insufficient to show differences in any members within the angiotensin II receptor blocker drug class with respect to blood pressuring lowering effects or a reduction in cardiovascular diseases.

Improved control of blood pressure and albuminuria among patients with type-2 diabetes in Finnish open care

Risk of cardiovascular events within the diabetic population has decreased and survival increased with patients living longer and thus facing the development of end-stage renal disease (ESRD). This calls for good care of patient with diabetes with a focus on hypertension. Patient data were collected from 42 Finnish primary care centres. Each was asked to enrol 10-12 consecutive patients with type-2 diabetes between March 2011 and August 2012. Along with the office blood pressure measurements and laboratory tests, the presence of albuminuria was measured and glomerular filtration rate estimated (eGFR). The 2013 ESH criteria for diabetic hypertensive patients (<140/85 mmHg) was reached by 39% of all 625 study patients and 38% of the pharmacologically treated 520 patients. The absence of detectable albumin in urine was significantly associated with the control of systolic blood pressure and achievement of treatment goals. Beta blockers were the most common antihypertensive agents and patients treated with them had lower eGFR compared to those not treated with these agents. The blood pressure of patients was not in full concordance with the present guideline recommendations. However, satisfactory improvement in blood pressure control, reduction of albuminuria and hence ESRD prevention was achieved.

Treatment of hypertensive patients with diabetes: beyond blood pressure control and focus on manidipine

Renin-angiotensin system inhibitors should be considered as the first-line therapy in the treatment of patients with hypertension and diabetes. However, most of the diabetic subjects with hypertension require at least two drugs to achieve blood pressure targets. The ACCOMPLISH trial suggested that the best combination in the treatment of high-risk hypertensive patients should include a renin-angiotensin system inhibitor and a dihydropyridine. However, not all dihydropyridines block the same receptors. Those dihydropyridines that block T-type calcium channel blockers may provide additional advantages. A number of studies suggest that compared with amlodipine, manidipine have the same antihypertensive efficacy, but with a lesser risk of ankle edema. In addition, manidipine, but not amlodipine, significantly reduces urinary albumin excretion rates.

Diabetic Kidney Disease: A Syndrome Rather Than a Single Disease

The term "diabetic kidney" has recently been proposed to encompass the various lesions, involving all kidney structures that characterize protean kidney damage in patients with diabetes. While glomerular diseases may follow the stepwise progression that was described several decades ago, the tenet that proteinuria identifies diabetic nephropathy is disputed today and should be limited to glomerular lesions. Improvements in glycemic control may have contributed to a decrease in the prevalence of glomerular lesions, initially described as hallmarks of diabetic nephropathy, and revealed other types of renal damage, mainly related to vasculature and interstitium, and these types usually present with little or no proteinuria. Whilst glomerular damage is the hallmark of microvascular lesions, ischemic nephropathies, renal infarction, and cholesterol emboli syndrome are the result of macrovascular involvement, and the presence of underlying renal damage sets the stage for acute infections and drug-induced kidney injuries. Impairment of the phagocytic response can cause severe and unusual forms of acute and chronic pyelonephritis. It is thus concluded that screening for albuminuria, which is useful for detecting "glomerular diabetic nephropathy", does not identify all potential nephropathies in diabetes patients. As diabetes is a risk factor for all forms of kidney disease, diagnosis in diabetic patients should include the same combination of biochemical, clinical, and imaging tests as employed in non-diabetic subjects, but with the specific consideration that chronic kidney disease (CKD) may develop more rapidly and severely in diabetic patients.

Cause-specific mortality according to urine albumin creatinine ratio in the general population

BACKGROUND

Urine albumin creatinine ratio, UACR, is positively associated with all-cause mortality, cardiovascular disease and diabetes in observational studies. Whether a high UACR is also associated with other causes of death is unclear. We investigated the association between UACR and cause-specific mortality.

METHODS

We included a total of 9,125 individuals from two population-based studies, Monica10 and Inter99, conducted in 1993-94 and 1999-2001, respectively. Urine albumin creatinine ratio was measured from spot urine samples by standard methods. Information on causes of death was obtained from The Danish Register of Causes of Death until 31 December 2010. There were a total of 920 deaths, and the median follow-up was 11.3 years.

RESULTS

Multivariable Cox regression analyses with age as underlying time axis showed statistically significant positive associations between UACR status and risk of all-cause mortality, endocrine nutritional and metabolic diseases, mental and behavioural disorders, diseases of the circulatory system, and diseases of the respiratory system with hazard ratios 1.56, 6.98, 2.34, 2.03, and 1.91, for the fourth UACR compared with the first, respectively. Using UACR as a continuous variable, we also found a statistically significant positive association with risk of death caused by diseases of the digestive system with a hazard ratio of 1.02 per 10 mg/g higher UACR.

CONCLUSION

We found statistically significant positive associations between baseline UACR and death from all-cause mortality, endocrine nutritional and metabolic diseases, and diseases of the circulatory system and possibly mental and behavioural disorders, and diseases of the respiratory and digestive system.

ARB-based single-pill platform to guide a practical therapeutic approach to hypertensive patients

Hypertension is a major modifiable risk for the development of cardiovascular, cerebrovascular and renal diseases. Thus, effective treatment of high blood pressure is an important strategy for reducing disease burden; however, in spite of the availability of numerous effective therapies only 30-40 % of patients with hypertension achieve the recommended blood pressure goals of <140/90 mmHg. Lack of adherence to therapy and reluctance to intensify therapy are cited frequently to explain the discrepancy between potential and attained outcomes. Adherence is closely related to the tolerability, effectiveness and complexity of therapy. Therapeutic inertia may be influenced by concerns over tolerability, as well as the lack of clear preferences for therapies when managing patients with risk factors and comorbidities. Effective and well-tolerated single pill combination therapies are now available that improve adherence and simplify treatment. The combination of a renin-angiotensin system blocker with a calcium channel blocker and a diuretic improves adherence to therapy. We have devised a practical tool for orienting the application of well-tolerated single pill 2/3 drug fixed dose combination therapies in clinical situations commonly encountered when treating hypertensive patients. This approach employs the angiotensin receptor blocker olmesartan alone or in combinations with amlodipine and/or hydrochlorothiazide. This platform is based on clinical evidence, guidelines, best practice, and clinical experience where none of these is available. We believe it will increase the percentage of hypertensive patients who achieve blood pressure control when applied as part of an integrative approach that includes regular follow-up and instruction on lifestyle changes.

Renin-angiotensin system blocking drugs

The two major classes of drugs that target the RAS are the angiotensin-converting enzyme (ACE) inhibitors and the selective AT1 receptor blockers (ARBs). Although both of these drug classes target angiotensin II, the differences in their mechanisms of action have implications for their effects on other pathways and receptors that may have therapeutic implications. Both ACEIs and ARBs are effective antihypertensive agents that have been shown to reduce the risk of cardiovascular and renal events. Direct inhibition of renin -the most proximal aspect of the RAS -became clinically feasible from 2007 with the introduction of aliskiren. This latter drug has been shown to be efficacious for the management of hypertension. Combined therapy of direct renin-inhibitors with ACEIs or ARBs has been tested in some clinical situations as congestive HF and proteinuria with diverse results. This article tries to offer an updated review of current knowledge on the use of RAS blocking drugs in clinical settings.

ANGIOTENSIN II RECEPTOR ANTAGONISTS AND NEPHROPROTECTION: PLACE OF OLMESARTAN

The paper presents the results of experimental studies and clinical trials which demonstrate nephroprotective effects of olmesartan. 

An evaluation of the latest evidence relating to renin-angiotensin system inhibitors

INTRODUCTION

In the last few years, a number of important clinical trials have been completed that have investigated the inhibition of the renin-angiotensin system. New drugs, focusing on this system, have now emerged as a result.

AREAS COVERED

The authors review the most relevant information available, reported from the last 5 years, pertaining to the most important clinical trials on renin-angiotensin system blockers (ARBs). The authors' data review includes the trials of aliskiren, telmisartan, olmesartan and azilsartan. The authors also review the possible risk of cancer with ARBs.

EXPERT OPINION

The results of ASPIRE and ALTITUDE trials strongly suggested that dual inhibition of aliskiren with either ARBS or angiotensin converting enzyme inhibitors (ACEi) should be avoided. Olmesartan is an effective and safe antihypertensive agent, but special attention should be paid to high-risk patients, such as those with coronary disease, to avoid an excessive reduction in blood pressure. The authors also note that while azilsartan is probably the most potent ARB, there is still a lack of data regarding potential organ damage and the incidence of cardiovascular events. Lastly, recent evidence has shown a lack of a relationship between ARB therapy and the occurrence of cancer.

Update on the ROADMAP clinical trial report: olmesartan for the prevention or delay of microalbuminuria development in type 2 diabetes

Albuminuria is associated with renal disease progression and cardiovascular disease development or cardiovascular complications in individuals at low, medium and high risk for these outcomes. Furthermore, in patients with vascular disease, changes in albuminuria independently predict mortality and cardiovascular and renal outcomes, and drug-induced lowering of albuminuria with the use of angiotensin-converting enzyme inhibitors and angiotensin receptor blockers confers long-term cardiovascular and renal protection. However, few studies have directly examined whether these agents might also prevent the development of albuminuria and whether this translates into protection from cardiovascular disease events. The ROADMAP trial was conducted in an attempt to give answers to these questions. The results provide evidence that pharmacological blockade of angiotensin II receptors is effective in reducing the risk of new-onset albuminuria in type 2 diabetic patients. The study was not able to determine if this will also lead to a long-term reduction of cardiovascular morbidity and mortality.

Antihypertensive agents for preventing diabetic kidney disease

BACKGROUND

Various blood pressure-lowering agents, and particularly inhibitors of the renin-angiotensin system (RAS), are widely used for people with diabetes to prevent the onset of diabetic kidney disease (DKD) and adverse cardiovascular outcomes. This is an update of a Cochrane review first published in 2003 and updated in 2005.

OBJECTIVES

This systematic review aimed to assess the benefits and harms of blood pressure lowering agents in people with diabetes mellitus and a normal amount of albumin in the urine (normoalbuminuria).

SEARCH METHODS

In January 2011 we searched the Cochrane Renal Group's Specialised Register through contact with the Trials Search Co-ordinator.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing any antihypertensive agent with placebo or another agent in hypertensive or normotensive patients with diabetes and no kidney disease (albumin excretion rate < 30 mg/d) were included.

DATA COLLECTION AND ANALYSIS

Two investigators independently extracted data on kidney and other patient-relevant outcomes (all-cause mortality and serious cardiovascular events), and assessed study quality. Analysis was by a random effects model was applied to analyse results which were expressed as risk ratio (RR) and 95% confidence intervals (CI).

MAIN RESULTS

We identified 26 studies that enrolling 61,264 participants. Angiotensin-converting enzyme inhibitors (ACEi) reduced the risk of new onset of microalbuminuria, macroalbuminuria or both when compared to placebo (8 studies, 11,906 patients: RR 0.71, 95% CI 0.56 to 0.89), with similar benefits in people with and without hypertension (P = 0.74), and when compared to calcium channel blockers (5 studies, 1253 participants: RR 0.60, 95% CI 0.42 to 0.85). ACEi reduced the risk of death when compared to placebo (6 studies, 11,350 participants: RR 0.84, 95% CI 0.73 to 0.97). No effect was observed for angiotensin receptor blockers (ARB) when compared to placebo for new microalbuminuria, macroalbuminuria or both (5 studies, 7653 participants: RR 0.90, 95% CI 0.68 to 1.19) or death (5 studies, 7653 participants: RR 1.12, 95% CI 0.88 to 1.41); however, meta-regression suggested possible benefits from ARB for preventing kidney disease in high risk patients. There was a trend towards benefit from use of combined ACEi and ARB for prevention of DKD compared with ACEi alone (2 studies, 4171 participants: RR 0.88, 95% CI 0.78 to 1.00).The risk of cough was significantly increased with ACEi when compared to placebo (6 studies, 11,791 patients: RR 1.84, 95% CI 1.24 to 2.72), however there was no significant difference in the risk of headache or hyperkalaemia. There was no significant difference in the risk of cough, headache or hyperkalaemia when ARB was to placebo. On average risk of bias was judged to be either low (27% to 69%) or unclear (i.e. no information available) (8% to 73%). Blinding of participants, incomplete outcome data and selective reporting were judged to be high in 23%, 31% and 31% of studies, respectively.

AUTHORS' CONCLUSIONS

ACEi were found to prevent new onset DKD and death in normoalbuminuric people with diabetes, and could therefore be used in this population. More data are needed to clarify the role of ARB and other drug classes in preventing DKD.

The effect of antihypertensive drugs on chronic kidney disease: a comprehensive review

Data from randomized clinical trials and epidemiological evidence identify systemic hypertension as the second most common modifiable risk factor for chronic kidney disease (CKD) progression after diabetes mellitus. CKD may progress silently over the years and early diagnosis and control of hypertension is of major importance in delaying renal function decline. Recent guidelines for the treatment of hypertension suggest the use of a variety of antihypertensive drugs in order to achieve the desired blood pressure levels. Renin-angiotensin system inhibitors have been undoubtedly studied the most and are suggested by guidelines and experts as first choice in patients with hypertension and renal injury, particularly in those with diabetes, as they have repeatedly shown to significantly reduce proteinuria. Other classes of antihypertensive drugs have been studied to a lesser extent and they have their own unique properties and effects. However, it is now common knowledge that adequate blood pressure control is the most important factor for the preservation of renal function, so every drug that effectively lowers hypertension is believed to be renoprotective. The present article will review the latest data on the role and properties of each class of antihypertensive drugs on CKD.