Does albuminuria predict cardiovascular outcome on treatment with losartan versus atenolol in hypertension with left ventricular hypertrophy? A LIFE substudy

Sonographic Optic Nerve Diameter and Clinical Biomarkers in Patients With Poorly Controlled Diabetes: A Comparative Analysis With Nondiabetic Subjects

Objective:

The study assessed optic nerve diameter (OND) and clinical biomarkers in patients with poorly controlled diabetes compared with healthy nondiabetic volunteers.

Materials and Methods:

There were 1320 adult participants recruited to the study. The cohort was divided into 600 Type 2 diabetic (DM II) patients and 720 apparently healthy, nondiabetic volunteers. The OND was measured using a high-resolution dedicated ultrasound device (Sonoace 5500; Medicol, Medison, Miami, FL, USA) with a 10-MHz linear array transducer. Subjects were examined in a supine position with their eyes closed. Three measurements of the OND were taken and the average recorded. Hemoglobin A1c concentration and lipid profiles were determined using Bio-Rad Diamat analyzer (Bio-Rad, Hercules, CA). Body mass index and age were matched for both cohorts for comparativeness.

Results:

The mean OND of the DM II patients was 3.10 ± 0.14 mm (range of 2.6–4.0 mm), which was significantly ( P < .05) lower than the control volunteers (4.22 ± 0.15 mm). The OND demonstrated a negative significant correlation with HA1c, duration of diabetes and low-density lipoprotein cholesterol level ( P < .05). Lipid profiles, blood urea, serum creatinine, and hemoglobin A1c showed statistical difference between diabetics and control subjects.

Conclusion:

Poorly controlled DM II patients may have significantly narrower OND than nondiabetic patients. This imaging biomarker has the potential to transform visual care for DM II patients.

The Blockade of TACE-Dependent EGF Receptor Activation by Losartan-Erlotinib Combination Attenuates Renal Fibrosis Formation in 5/6-Nephrectomized Rats Under Vitamin D Deficiency

Chronic kidney disease (CKD) has been considered a major public health issue. In addition to cardiovascular diseases and infections, hypovitaminosis D has been considered a non-traditional aggravating factor for CKD progression. Interstitial fibrosis is a hallmark of CKD strongly correlated with deterioration of renal function. Transforming growth factor β (TGF-β) is the major regulatory profibrotic cytokine in CKD. Many injurious stimuli converge on the TGF-β pathway, which has context-dependent pleiotropic effects and interacts with several related renal fibrosis formation (RFF) pathways. Epidermal growth factor receptor (EGFR) is critically involved in CKD progression, exerting a pathogenic role in RFF associated with TGF-β-related fibrogenesis. Among others, EGFR pathway can be activated by a disintegrin and a metalloproteinase known as tumor necrosis factor α-converting enzyme (TACE). Currently no effective therapy is available to completely arrest RFF and slow the progression of CKD. Therefore, we investigated the effects of a double treatment with losartan potassium (L), an AT1R antagonist, and the tyrosine kinase inhibitor erlotinib (E) on the alternative pathway of RFF related to TACE-dependent EGFR activation in 5/6-nephrectomized rats under vitamin D deficiency (D). During the 90-day protocol, male Wistar rats under D, were submitted to 5/6 nephrectomy (N) on day 30 and randomized into four groups: N+D, no treatment; N+D+L, received losartan (50 mg/kg/day); N+D+E, received erlotinib (6 mg/kg/day); N+D+L+E received losartan+erlotinib treatment. N+D+L+E data demonstrated that the double treatment with losartan+erlotinib not only blocked the TACE-dependent EGF receptor activation but also prevented the expression of TGF-β, protecting against RFF. This renoprotection by losartan+erlotinib was corroborated by a lower expression of ECM proteins and markers of phenotypic alteration as well as a lesser inflammatory cell infiltrate. Although erlotinib alone has been emerging as a renoprotective drug, its association with losartan should be considered as a potential therapeutic strategy on the modulation of RFF.

Role of Vitamin D Status in Diabetic Patients with Renal Disease

Diabetes mellitus (DM) poses a major public health problem worldwide, with ever-increasing incidence and prevalence in recent years. The Institute for Alternative Futures (IAF) expects that the total number of people with type 1 and type 2 DM in the United States will increase by 54%, from 19,629,000 to 54,913,000 people, between 2015 and 2030. Diabetic Nephropathy (DN) affects about one-third of patients with DM and currently ranks as the first cause of end-stage kidney disease in the Western world. The complexity of interactions of Vitamin D is directly related with progressive long-term changes implicated in the worsening of renal function. These changes result in a dysregulation of the vitamin D-dependent pathways. Various studies demonstrated a pivotal role of Vitamin D supplementation in regression of albuminuria and glomerulosclerosis, contrasting the increase of glomerular basement membrane thickening and podocyte effacement, with better renal and cardiovascular outcomes. The homeostasis and regulation of the nephron’s function are absolutely dependent from the cross-talk between endothelium and podocytes. Even if growing evidence proves that vitamin D may have antiproteinuric, anti-inflammatory and renoprotective effects in patients with DN, it is still worth investigating these aspects with both more in vitro studies and randomized controlled trials in larger patient series and with adequate follow-up to confirm the effects of long-term vitamin D analogue supplementation in DN and to evaluate the effectiveness of this therapy and the appropriate dosage.

New Areas of Interest: Is There a Role for Omega-3 Fatty Acid Supplementation in Patients With Diabetes and Cardiovascular Disease?

PURPOSE OF REVIEW

Summarize studies on omega-3 fatty acids in prevention of albuminuria in subjects with diabetes.

RECENT FINDINGS

Several small, short-term trials suggested benefit on albuminuria in subjects with diabetes; however, results were not definitive. Welty et al. showed that eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) for 1 year slowed progression of early-stage albuminuria in subjects with diabetes with clinical coronary artery disease on an angiotensin-converting enzyme inhibitor or angiotensin-receptor blocker, the majority of whom had an albumin/creatinine ratio (ACR) < 30 μg/mg. Moreover, significantly more (3-fold) subjects on EPA and DHA had a decrease in ACR compared to control, and three on EPA and DHA had a change in category from > 30 μg/mg to < 30 μg/mg, whereas no controls did. Potential mechanisms for benefit are discussed. These results suggest that there is benefit and perhaps even reversal of albuminuria with EPA and DHA at an early stage of disease in those with ACR < 30 μg/mg and those with microalbuminuria (ACR > 30).

Fifteen years of LIFE (Losartan Intervention for Endpoint Reduction in Hypertension)-Lessons learned for losartan: An "old dog playing good tricks"

There is an unmet need to prevent cardiovascular disease and chronic kidney disease development and progression worldwide. Losartan, the first angiotensin receptor blocker, was shown to exert significant cardioprotective and renoprotective effects in the LIFE (Losartan Intervention for Endpoint Reduction in Hypertension) and RENAAL (Reduction of Endpoints in NIDDM With the Angiotensin II Antagonist Losartan) trials. Losartan significantly prevented stroke and decreased serum uric acid levels and the rates of new-onset diabetes mellitus and atrial fibrillation. The present review discusses the LIFE (and its subanalyses) and RENAAL trials and the translation of their results to clinical practice. The place of losartan in the current guidelines for hypertension management is also discussed. Losartan still represents an efficacious, safe, and cost-effective therapeutic option in patients with hypertension who have left ventricular hypertrophy. Losartan is a useful antihypertensive agent for stroke prevention and in the management of patients with chronic kidney disease, atrial fibrillation, diabetes mellitus, albuminuria, and hyperuricemia.

Microalbuminuria: Correlation With Prevalence and Severity of Coronary Artery Disease in Non-Diabetics

BACKGROUND

Previous studies have shown that microalbuminuria (MAU) is an independent risk factor for cardiovascular diseases in diabetics, hypertensive patients and in the general population. However, the correlation of MAU with the severity of coronary artery disease (CAD) in non-diabetic patients has not been addressed in detail. This study aimed to investigate the relationship between MAU and severity of angiographically confirmed CAD in non-diabetic patients.

METHODS

This was a cross-sectional study, which included 90 non-diabetic patients with documented CAD by coronary angiography. The ratio of urine albumin to creatinine was used to define MAU and severity of CAD was estimated using SYNTAX score. Patients were divided into two groups: group I that included patients without MAU and group II that included patients with MAU.

RESULTS

Out of 90 non-diabetic CAD patients, 62 (68.9%) were in group I (MAU negative) and 28 (31.1%) were in group II (MAU positive). There was statistically significant difference in the median SYNTAX score between the groups (21 vs. 28, P < 0.001). The prevalences of double vessel CAD and triple vessel CAD were significantly higher in MAU positive group. There was a strong relationship between the presence of MAU and the extent and complexity of CAD (r = 0.094; P < 0.001).

CONCLUSION

Thus, we conclude that patients with MAU have more severe angiographically detected CAD than those without MAU, and MAU exhibits a significant association with the presence and severity of CAD.

Eicosapentaenoic and Docosahexaenoic Acids Attenuate Progression of Albuminuria in Patients With Type 2 Diabetes Mellitus and Coronary Artery Disease

Background

Albuminuria is a marker of inflammation and an independent predictor of cardiovascular morbidity and mortality. The current study evaluated whether eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) supplementation attenuates progression of albuminuria in subjects with coronary artery disease.

Methods and Results

Two‐hundred sixty‐two subjects with stable coronary artery disease were randomized to either Lovaza (1.86 g of EPA and 1.5 g of DHA daily) or no Lovaza (control) for 1 year. Percent change in urine albumin‐to‐creatinine ratio (ACR) was compared. Mean (SD) age was 63.3 (7.6) years; 17% were women and 30% had type 2 diabetes mellitus. In nondiabetic subjects, no change in urine ACR occurred in either the Lovaza or control groups. In contrast, ACR increased 72.3% (P<0.001) in diabetic subjects not receiving Lovaza, whereas those receiving Lovaza had no change. In diabetic subjects on an angiotensin‐converting enzyme‐inhibitor or angiotensin‐receptor blocker, those receiving Lovaza had no change in urine ACR, whereas those not receiving Lovaza had a 64.2% increase (P<0.001). Change in ACR was directly correlated with change in systolic blood pressure (r=0.394, P=0.01).

Conclusions

EPA and DHA supplementation attenuated progression of albuminuria in subjects with type 2 diabetes mellitus and coronary artery disease, most of whom were on an angiotensin‐converting enzyme‐inhibitor or angiotensin‐receptor blocker. Thus, EPA and DHA supplementation should be considered as additional therapy to an angiotensin‐converting enzyme‐inhibitor or angiotensin‐receptor blocker in subjects with type 2 diabetes mellitus and coronary artery disease.

Clinical Trial Registration

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01624727.

Subclinical Kidney Damage in Hypertensive Patients: A Renal Window Opened on the Cardiovascular System. Focus on Microalbuminuria

The kidney is one of the major target organs of hypertension.Kidney damage represents a frequent event in the course of hypertension and arterial hypertension is one of the leading causes of end-stage renal disease (ESRD).ESRD has long been recognized as a strong predictor of cardiovascular (CV) morbidity and mortality. However, over the past 20 years a large and consistent body of evidence has been produced suggesting that CV risk progressively increases as the estimated glomerular filtration rate (eGFR) declines and is already significantly elevated even in the earliest stages of renal damage. Data was supported by the very large collaborative meta-analysis of the Chronic Kidney Disease Prognosis Consortium, which provided undisputable evidence that there is an inverse association between eGFR and CV risk. It is important to remember that in evaluating CV disease using renal parameters, GFR should be assessed simultaneously with albuminuria.Indeed, data from the same meta-analysis indicate that also increased urinary albumin levels or proteinuria carry an increased risk of all-cause and CV mortality. Thus, lower eGFR and higher urinary albumin values are not only predictors of progressive kidney failure, but also of all-cause and CV mortality, independent of each other and of traditional CV risk factors.Although subjects with ESRD are at the highest risk of CV diseases, there will likely be more events in subjects with mil-to-moderate renal dysfunction, because of its much higher prevalence.These findings are even more noteworthy when one considers that a mild reduction in renal function is very common in hypertensive patients.The current European Society of Hypertension (ESH)/European Society of Cardiology (ESC) guidelines for the management of arterial hypertension recommend to sought in every patient signs of subclinical (or asymptomatic) renal damage. This was defined by the detection of eGFR between 30 mL/min/1.73 m² and 60 mL/min/1.73 m² or the presence of microalbuminuria (MAU), that is an amount of albumin in the urine of 30-300 mg/day or an albumin/creatinine ratio, preferentially on morning spot urine, of 30-300 mg/g.There is clear evidence that urinary albumin excretion levels, even below the cut-off values used to define MAU, are associated with an increased risk of CV events. The relationships of MAU with a variety of risk factors, such as blood pressure, diabetes and metabolic syndrome and with several indices of subclinical organ damage, may contribute, at least in part, to explain the enhanced CV risk conferred by MAU. Nonetheless, several studies showed that the association between MAU and CV disease remains when all these risk factors are taken into account in multivariate analyses. Therefore, the exact pathophysiological mechanisms explaining the association between MAU and CV risk remain to be elucidated. The simple search for MAU and in general of subclinical renal involvement in hypertensive patients may enable the clinician to better assess absolute CV risk, and its identification may induce physicians to encourage patients to make healthy lifestyle changes and perhaps would prompt to more aggressive modification of standard CV risk factors.

Reduction of microalbuminuria in type-2 diabetes mellitus with angiotensin-converting enzyme inhibitor alone and with cilnidipine

The aim of our study was to find out the antiproteinuric effect of enalapril angiotensin-converting enzyme (ACE inhibitor) alone or in combination with cilnidipine in patients with type-2 diabetes mellitus. The study was conducted on 71 patients with type-2 diabetes mellitus patients with hypertension and microalbuminuria. They were divided into two groups randomly as follows: Group I (enalaprilalone, n = 36) and Group II (enalapril with cilnidipine, n = 35). In both the groups, baseline 24 h urinary albumin was estimated and was repeated every 3 months upto 1-year. After 1-year follow-up, reduction in microalbuminuria was found to be greater in Group II. In Group I microalbuminuria came down by 25.68 ± 21.40 while in Group II it reduced by 54.88 ± 13.84 (P < 0.001). We conclude that in diabetic population, cilnidipine has an additive effect in microalbuminuria reduction over and above the well-proven effect of ACE inhibitors.

Association between urinary albumin excretion and intraocular pressure in type 2 diabetic patients without renal impairment

Background

To assess the relationship between urinary albumin excretion and intraocular pressure (IOP) in type 2 diabetes patients without renal impairment.

Methods

We explored the effects of albuminuria on high IOP in 402 non-glaucomatous type 2 diabetes without renal impairment who participated in the 2011 Korean National Health and Nutrition Examination Survey (KNHANES). Multiple logistic regression analysis was used to assess the relationship between log-transformed albumin/creatinine ratio (ACR) tertiles and an IOP of ≥18 mmHg after adjusting for age, gender, hypertension, body mass index, triglycerides, area of residence, and education level.

Results

Subjects with a high IOP ≥18 mmHg were more likely to be current smokers (P = 0.038), heavy drinkers (P = 0.006), and to have high systolic blood pressure (P = 0.016), triglycerides (P = 0.008), and a higher log-transformed ACR (P = 0.022).In multivariate regression analysis, ACR tertile was associated with the prevalence of high IOP significantly (P = 0.022). The associations between ACR tertiles and high IOP were significant in overweight patients and those with abdominal obesity (P = 0.003 and 0.003, respectively). In contrast, there were no associations in the subgroup of patients who were not overweight and those without abdominal obesity (P = 0.291 and 0.561, respectively).

Conclusions

Urinary albumin excretion is associated with high IOP in the type 2 diabetes population without renal insufficiency. The effect of the albuminuria on IOP was evident in a subgroup of patients with components of metabolic syndrome.

ACE inhibitors or ARBs for diabetic nephropathy: the unrelenting debate

Adequate control of blood pressure is of paramount importance in delaying the progression of renal disease in diabetic patients. Drugs acting on renin angiotensin aldosterone axis are of proven value in diabetes. Particularly angiotensin converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) have benefits beyond blood pressure control. The current article focuses on various studies supporting the use of ACEIs and ARBs in diabetic subjects.

Losartan versus atenolol-based antihypertensive treatment reduces cardiovascular events especially well in elderly patients: the Losartan Intervention For Endpoint reduction in hypertension (LIFE) study

BACKGROUND

The Losartan Intervention For Endpoint reduction in hypertension (LIFE) study has previously demonstrated a beneficial effect of losartan compared to atenolol-based antihypertensive treatment in patients with essential hypertension and left-ventricular hypertrophy (LVH). However, patient age often influences the choice of antihypertensive drugs. Therefore, we investigated the influence of age on the effects of losartan versus atenolol-based antihypertensive treatment.

METHODS

A total of 9193 hypertensive patients with LVH aged 45-83 years were followed for a mean of 4.8 years. Blood pressure, high-density lipoprotein cholesterol (HDL-C), Sokolow-Lyon voltage, Cornell voltage-duration product and urine albumin-creatinine ratio (UACR) were measured yearly throughout the study. Patients were divided into two age groups according to the median age of 67 years and the effects of losartan versus atenolol-based antihypertensive treatment on the primary composite endpoint (CEP) consisting of cardiovascular death, nonfatal stroke or nonfatal myocardial infarction were investigated.

RESULTS

The beneficial effect of losartan versus atenolol-based treatment was greater in the group of patients older than 67 years [hazard ratio 0.79 (0.69-0.91), P = 0.001] compared to the group of patients younger than 67 years [hazard ratio 1.03 (0.82-1.28), P = 0809], P = 0.045 for interaction. The beneficial effects of losartan versus atenolol-based antihypertensive treatment on pulse pressure, HDL-C, UACR, and Cornell and Sokolow-Lyon voltage were not more pronounced in patients older than 67 years compared to patients younger than 67 years. All five risk factors considered as time-varying covariates predicted CEP independently (P < 0.01) with the exception of pulse pressure (P = 0.37) and the interaction between age and treatment on outcome remained significant (P = 0.042).

CONCLUSIONS

We showed a greater beneficial effect of losartan versus atenolol-based antihypertensive treatment in the group of patients older than 67 years compared to the group of patients younger than 67 years. This difference was not explained by a more pronounced effect of losartan-based treatment on any of the cardiovascular risk factors demonstrated to have independent prognostic importance.

Microalbuminuria breakthrough under chronic renin-angiotensin-aldosterone system suppression

OBJECTIVES

Microalbuminuria has been shown to be a potent predictor for future development of cardiovascular and renal events that can be prevented by the use of angiotensin-converting enzyme inhibitors (ACEis) or angiotensin receptor blockers (ARBs). Both classes of drugs are now-a-days widely used in the treatment of arterial hypertension since the very early stages of the cardiorenal continuum when only cardiovascular risk factors are detected. We describe here the development of de-novo microalbuminuria in patients chronically treated with either an ACEi or an ARB at adequate doses.

METHODS

We reviewed the evolution of 1433 patients (mean age 60.5 ± 12.4 years, 50.3% men, 6.6% having type 2 diabetes), arriving in our hospital-based Hypertension Unit previously treated for a least 2 years either with an ACEi or an ARB, at adequate doses, alone or in combination with other antihypertensive drugs.

RESULTS

A total of 184 (16.1%) patients developed new-onset microalbuminuria, whereas macroalbuminuria was detected in 11 (1.0%) patients at the end of follow-up. Albuminuria appeared at any level of blood pressure (BP) from below 130/80 mmHg, albeit the highest percentage was seen when SBP was above 160 mmHg. De-novo microalbuminuria was more frequent in those patients presenting with established cardiovascular disease and predicts the future development of cardiovascular events but was not accompanied by a significant worsening of renal function.

CONCLUSION

These data indicate that a reappraisal of renin-angiotensin-aldosterone system (RAAS) suppression is required when microalbuminuria appears in patients under chronic RAAS suppression.

End-organ protection in patients with hypertension: focus on the role of angiotensin receptor blockers on renal function

The renin-angiotensin system (RAS) plays a key role in a number of pathophysiological mechanisms that are involved in the development and progression of cardiovascular and renal disease. For these reasons, pharmacological antagonism of this system, particularly the blockade of formation or the receptor antagonism of angiotensin II, has been demonstrated to be an effective and safe strategy to reduce the burden of cardiovascular disease. Among different drug classes, angiotensin II type 1 receptor antagonists (angiotensin receptor blockers [ARBs]) have provided an excellent alternative to ACE inhibitors, representing a more selective and a better tolerated pharmacological approach to interfere with the RAS. Results derived from large, international, randomized clinical trials have consistently indicated that ARB-based therapeutic strategies may effectively provide cardiovascular and renal disease prevention and protection in different clinical conditions across the entire cardiovascular continuum. This article reviews the pathophysiological rationale of RAS involvement in the pathogenesis of renal diseases, focusing on the beneficial effects provided by ARBs in terms of renal protection.

The progressive pathway of microalbuminuria: from early marker of renal damage to strong cardiovascular risk predictor

There is clear evidence that urinary albumin excretion levels, even below the cut-off values currently used to diagnose microalbuminuria, are associated with an increased risk of cardiovascular events. The relationships of microalbuminuria with a variety of risk factors, such as hypertension, diabetes and metabolic syndrome and with several indices of subclinical organ damage, may contribute, at least in part, to explain the enhanced cardiovascular risk conferred by microalbuminuria. Nonetheless, several studies showed that the association between microalbuminuria and cardiovascular disease remains when all these risk factors are taken into account in multivariate analyses. Therefore, the exact pathophysiological mechanisms explaining the association between microalbuminuria and cardiovascular risk remain incompletely understood. The simple search for microalbuminuria in hypertensive patients may enable the clinician to better assess absolute cardiovascular risk, and its identification may induce physicians to encourage patients to make healthy lifestyle changes and perhaps would prompt to more aggressive modification of standard cardiovascular risk factors.

Outcomes of antiproteinuric RAAS blockade: high-dose compared with dual therapy

Proteinuria is both a marker and a mediator of progressive renal damage; higher levels are associated with greater cardiovascular and renal risk. At normal and low levels of proteinuria (in the microalbuminuria range), the rate of hard renal events (dialysis and doubling of creatinine) is much lower than the mortality rate. At higher levels of proteinuria, the renal event rate surpasses the mortality rate. In the overt nephropathy range (proteinuria > 0.5 g/L), patients who achieve lower proteinuria with therapy have improved hard renal outcomes, but this result has not been demonstrated in the micro-albuminuria range. For patients with more severe overt nephropathy, there is a basic rationale for additional blockade of the renin-angiotensin-aldosterone system (RAAS). Dual blockade of this system and supramaximal dosing with an angiotensin-converting enzyme (ACE) inhibitor or an angiotensin receptor blocker (ARB) have been demonstrated to reduce proteinuria in these patients more than therapy using the maximum recommended doses of these agents. However, evidence that dual blockade provides additional benefits for hard renal and cardiovascular outcomes is lacking, and only one study shows a benefit for supramaximal dosing. Both treatment strategies increase the risk for complications such as hyperkalemia. Therapy for patients with nephropathy should include treatment with the maximum recommended doses of an ACE inhibitor or ARB in addition to lowering blood pressure to target. For patients with overt nephropathy, more research is required on the role of dual therapy or supramaximal dosing to reduce hard renal and cardiovascular outcomes. Practitioners using either of these strategies to manage proteinuria should monitor their patients carefully.

Cardiorenal risk factors

The chronic renocardiac syndrome, in which chronic kidney disease (CKD) contributes to impairment of cardiac function or structure, is associated with an increased risk of adverse cardiovascular events. The prevalence of CKD in the U.S. population is approximately 11% and has been increasing over time. Numerous studies have demonstrated an association of CKD, defined by the presence of reduced glomerular filtration rate and/or albuminuria with adverse cardiovascular and renal outcomes. These data suggest that both albuminuria and glomerular filtration rate, which can be performed with minimally increased costs, should be included in the assessment of risk stratification for individual patients, in addition to traditional cardiovascular risk factors.

Fifteen years of losartan: what have we learned about losartan that can benefit chronic kidney disease patients?

Losartan, the first AT1 receptor blocker (ARB), was FDA approved 15 years ago. During those years, researchers and clinicians have developed a growing base of knowledge on the benefits of losartan, particularly for hypertension and renal disease. These benefits include decreasing proteinuria, slowing the progression of diabetic nephropathy, controlling hypertension, and decreasing stroke risk in patients with left ventricular hypertrophy. Although many of the benefits of losartan represent a class effect for ARBs, losartan has pharmacokinetic and pharmacodynamic characteristics and effects that are unique and are not a class effect. For example, a shorter duration of action is seen with this first ARB compared with other more recently approved ARBs. Losartan also has a uricosuric effect not seen in other ARBs and attenuates platelet aggregation, which is not seen or is seen to a lesser extent with the other ARBs. This review presents the physiological effects of losartan on the kidney and discusses relevant clinical outcomes.

Microalbuminuria is a predictor of chronic renal insufficiency in patients without diabetes and with hypertension: the MAGIC study

BACKGROUND AND OBJECTIVES

Increased urinary albumin excretion is a known risk factor for cardiovascular events and clinical nephropathy in patients with diabetes. Whether microalbuminuria predicts long-term development of chronic renal insufficiency (CRI) in patients without diabetes and with primary hypertension remains to be documented.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We conducted an 11.8-year follow-up of 917 patients who did not have diabetes and had hypertension and were enrolled in the Microalbuminuria: A Genoa Investigation on Complications (MAGIC) cohort between 1993 and 1997. Urinary albumin-to-creatinine ratio (ACR) was assessed at baseline in untreated patients in a core laboratory. Microalbuminuria was defined as ACR > or =22 mg/g in men and ACR > or =31 mg/g in women.

RESULTS

A total of 10,268 person-years of follow-up revealed that baseline microalbuminuria was associated with an increased risk for developing CRI (relative risk [RR] 7.61; 95% confidence interval [CI] 3.19 to 8.16; P < 0.0001), cardiovascular events (composite of fatal and nonfatal cardiac and cerebrovascular events; RR 2.11; 95% CI 1.08 to 4.13; P < 0.028), and cardiorenal events (composite of former end points; RR 3.21; 95% CI 1.86 to 5.53; P < 0.0001). Microalbuminuria remained significantly related to CRI (RR 12.75; 95% CI 3.62 to 44.92; P < 0.0001) and cardiorenal events (RR 2.58; 95% CI 1.32 to 5.05; P = 0.0056) even after adjustment for several baseline covariates.

CONCLUSIONS

Microalbuminuria is an independent predictor of renal and cardiovascular complications in patients without diabetes and with primary hypertension.

Predictors of cardiovascular events in patients with hypertension and left ventricular hypertrophy: the Losartan Intervention for Endpoint reduction in hypertension study

OBJECTIVE

We assessed readily available patient characteristics, including albuminuria (not included in traditional cardiovascular risk scores), as predictors of cardiovascular events in hypertension with left ventricular hypertrophy (LVH) and developed risk algorithms/scores for outcomes.

METHODS

The Losartan Intervention For Endpoint reduction in hypertension (LIFE) study compared effects of losartan-based versus atenolol-based therapy on cardiovascular events in 9193 patients with hypertension and LVH. Univariate and multivariate analyses identified baseline variables with significant impact on development of the primary composite endpoint (cardiovascular death, stroke and myocardial infarction) and its components. Multivariate analysis used a Cox regression model with stepwise selection process. Risk scores were developed from coefficients of risk factors from the multivariate analysis, validated internally using naïve and jack-knife procedures, checked for discrimination and calibration, and compared with Framingham coronary heart disease and other risk scores.

RESULTS

LIFE risk scores showed increasing endpoint rates with increasing quintile (first to fifth quintile, composite endpoint 2.8-26.7%, cardiovascular death 0.5-14.4%, stroke 1.2-11.3%, myocardial infarction 1.4-8.1%) and were confirmed with a jack-knife approach that adjusts for potentially optimistic bias. The Framingham coronary heart disease and other risk scores overestimated risk in lower risk patients and underestimated risk in higher risk patients, except for myocardial infarction.

CONCLUSION

A number of patient characteristics predicted cardiovascular events in patients with hypertension and LVH. Risk scores developed from these patient characteristics, including albuminuria, strongly predicted outcomes and may improve risk assessment of patients with hypertension and LVH and planning of clinical trials.

Effects of angiotensin II receptor blockers on diabetic nephropathy

Impaired kidney function increases the risk of cardiovascular morbidity and mortality. Coexistence of hypertension and type 2 diabetes increases the risk of kidney damage, hypertension being an independent risk factor for kidney disease progression. Angiotensin II, through its inflammatory, proliferative, and thrombotic effects, adversely affects renal perfusion and increases oxidative stress, thus playing a pivotal role in kidney disease progression. Angiotensin II receptor blockers (ARBs) and angiotensin-converting enzyme (ACE) inhibitors improve markers of kidney disease and slow kidney disease progression in diabetic and nondiabetic patients; this kidney protection may be in addition to their antihypertensive activity in those with advanced proteinuric nephropathy. Key beneficial effects of ARBs and ACE inhibitors throughout the kidney disease continuum are primarily explained by blood pressure lowering effects and partially by their direct blockade of angiotensin II. Recent studies have shown that telmisartan, an ARB with high lipophilicity and the longest half-life compared with other ARBs, provides benefits on markers of cardiovascular risk, that is, microalbuminuria and slowing of early-stage nephropathy.

End-organ dysfunction and cardiovascular outcomes: the role of the microcirculation

Risk factors for cardiovascular disease mediate their effects by altering the structure and function of wall and endothelial components of arterial blood vessels. A pathological change in the microcirculation plays a pivotal role in promoting end-organ dysfunction that not only predisposes to further organ damage, but also increases the risk for future macrovascular events. The microcirculation is recognized as the site where the earliest manifestations of cardiovascular disease, especially inflammatory responses, occur that may play a pivotal role in driving the atherosclerotic process in conduit vessels. Furthermore, the vast surface area of the endothelium compared with conduit vessels means that the vascular effects of endothelial dysfunction or activation will be most apparent in this section of the vasculature. Current techniques providing indices of vascular health focus on large arteries without providing insight into the structure and function of small vessels. Techniques capable of detecting microvascular damage and monitoring the response to therapeutic interventions, especially in vulnerable target organs of interest, may improve risk stratification and represent a valuable surrogate for future cardiovascular outcome.

ASH position paper: treatment of hypertension in patients with diabetes-an update

This report updates concepts on hypertension management in patients with diabetes. It focuses on clinical outcomes literature published within the last 3 years and incorporates these observations into modifications of established guidelines. While the fundamentals of treatment and goal blood pressures remain unchanged, approaches to specific patient-related issues has changed. This update focuses on questions such as what to do when a patient has an elevated potassium level when therapy is initiated and whether combinations of agents that block the renin-angiotensin system still be used. In addition, there are updates from trials, just published and in press, that focus on related management issues influencing cardiovascular outcomes in persons with diabetes. Last, an updated algorithm is provided that incorporates many of the new findings and is suggested as a starting point to achieve blood pressure goals.

The left atrium, atrial fibrillation, and the risk of stroke in hypertensive patients with left ventricular hypertrophy

The Losartan Intervention For Endpoint reduction in hypertension (LIFE) study provided extensive data on predisposing factors, consequences, and prevention of atrial fibrillation (AF) in patients with hypertension and left ventricular (LV) hypertrophy. Randomized losartan-based treatment was superior to atenolol-based treatment for reducing new-onset AF and complications, especially stroke, associated with new-onset or pre-existing AF. Potential mechanisms of AF prevention by angiotensin receptor blockade supported by LIFE results include greater reduction in left atrial size and LV hypertrophy. Differential effects of antihypertensive treatment on the left atrium and left ventricle may help prevent AF and reduce risk of stroke associated with hypertensive heart disease.

Managing hypertension in cardiology practice according to risk profile

Cardiologists play a central role in managing hypertensive patients, although recent surveys reveal a marked discrepancy between cardiologists' appreciation of their patients' risk status and the measures taken to reduce that risk. The diagnosis and the management of hypertension, in fact, must be viewed today not in isolation, but as part of a patients' global cardiovascular (CV) risk, resulting from the concomitant presence of a variety of risk factors, organ damage (left ventricular hypertrophy, carotid or peripheral atherosclerosis, microalbuminuria or impaired glomerular filtration rate), and hypertension-related clinical conditions. The choice of timing and the intensity of antihypertensive treatment should be based on blood pressure (BP)-lowering efficacy and the propensity to favourably impact patient's individual absolute CV disease risk profile. As part of this paradigm shift in CV disease prevention strategy, cardiologists can take several key steps to help improve standards of hypertension control: (i) increase the awareness of total risk management; (ii) initiate an integrated management strategy tailored to the individual patient's global CV risk (e.g. hypertension, hypercholesterolaemia, diabetes, age, smoking and gender); (iii) use any elevation in BP as a gateway to begin total risk management and (iv) utilise combination therapies (particularly fixed-dose combinations) to achieve more rapid and persistent BP control and improve patient compliance/persistence with therapy. To help improve standards of hypertension control in the cardiology setting, this review examines the concept of treating hypertension using a global risk assessment approach and proposes effective hypertensive therapy as part of global risk management in patients typically seen in cardiology practice.

Pulse pressure is an independent determinant of renal function decline during treatment of essential hypertension

BACKGROUND

In large epidemiological studies and using serum creatinine or estimates of glomerular filtration rate (GFR), blood pressure has emerged as a predominant determinant of the age-associated decline in renal function.

METHODS

The present longitudinal study (median follow-up period of 5.8 years) was conducted in 132 never-treated patients with essential hypertension at baseline. The effect of treatment on the GFR and effective renal plasma flow, estimated by urinary clearances of isotopic markers, was assessed.

RESULTS

Satisfactory control of hypertension (<140/90 mmHg) was achieved in 57% of the population. During follow-up, the yearly change in the GFR was -1.72+/-0.21 ml/min per year (mean+/-SEM). In univariate regression analysis, the change in the GFR was correlated with baseline pulse pressure (r=-0.27, P=0.002), whereas no influence of systolic, diastolic or mean blood pressures, as well as baseline albuminuria or left ventricular mass index, was found. Multivariate logistic regression analysis showed that only baseline pulse pressure conveyed a significant odds ratio of accelerated decline of GFR (>median of 1.5 ml/min per year), independently of age, baseline GFR, mean blood pressure and other known cardiovascular risk factors. No influence of the type of antihypertensive treatment (64% of the population had received angiotensin-converting enzyme inhibitor) was detected.

CONCLUSION

Pulse pressure (a marker of arterial stiffening) is suggested as an independent determinant of the treatment-associated decline in renal function in essential hypertension. No influence of target organ damage (albuminuria of left ventricular hypertrophy) was detected.

Microalbuminuria and urinary albumin excretion: French clinical practice guidelines

Urinary albumin excretion (UAE) may be assayed on a morning urinary sample or a 24 h-urine sample. Values defining microalbuminuria are: 1) 24-h urine sample: 30-300 mg/24 h; 2) morning urine sample: 20-200 mg/ml or 30-300 mg/g creatinine or 2.5-25 mg/mmol creatinine (men) or 3.5-35 mg/mmol (women); 3) timed urine sample: 20-200 mug/min. The optimal use of semi-quantitative urine test-strip is not clearly defined. It is generally believed that microalbuminuria reflects a generalized impairment of the endothelium; however, no definite proof has been obtained in humans.

IN DIABETIC SUBJECTS

Microalbuminuria is a marker of increased risk of cardiovascular (CV) and renal morbidity and mortality in type 1 and type 2 diabetic subjects. The increase in UAE during follow-up is associated with greater CV and renal risks in type 1 and type 2 diabetic subjects; its decrease during follow-up is associated with lower risks. IN NON-DIABETIC SUBJECTS: Microalbuminuria is a marker of increased risk for diabetes mellitus, deterioration of renal function, CV morbidity and all-cause mortality. It is a marker of increased risk for the development of hypertension in normotensive subjects, and is associated with unfavorable outcome in patients with cancer and lymphoma. Persistence of elevated UAE during follow-up is associated with poor outcome in some hypertensive subjects. Measurement of UAE may be recommended in hypertensive medium-risk subjects with 1 or 2 CV risk factors in whom CV risk remains difficult to assess, and in those with refractory hypertension: microalbuminuria indicates a high CV risk and must lead to strict control of arterial pressure. Studies focused on microalbuminuria in non-diabetic non-hypertensive subjects are limited; most of them suggest that microalbuminuria predicts CV complications and deleterious outcome. Subjects with a history of CV or cerebrovascular disease have an even greater CV risk if microalbuminuria is present than if it is not; however, in all cases, therapeutic intervention must be aggressive regardless of whether microalbuminuria is present or not. It is not recommended to measure UAE in non-diabetic non-hypertensive subjects in the absence of history of renal disease. Monitoring of renal function (UAE, serum creatinine and estimation of GFR) is recommended annually in all subjects with microalbuminuria.

MANAGEMENT

In patients with microalbuminuria, weight reduction, sodium restriction (<6 g per day), smoking cessation, strict glucose control in diabetic subjects, strict arterial pressure control are necessary; in diabetic subjects: use of maximal doses of angiotensin-converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARB) are recommended; ACEI/ARB and thiazides have synergistic actions on arterial pressure and reduction of UAE; in non-diabetic subjects, any of the five classes of anti-hypertensive medications (ACEI, ARB, thiazides, calcium channel blockers or beta-blockers) can be used.

Use of predictive markers to improve cardiovascular protection

Together with other modifiable cardiovascular risk factors, hypertension heavily contributes to the global burden of cardiovascular morbidity and mortality, as well as to the increase in individual absolute cardiovascular risk. Comparison of the effectiveness of different therapies in reducing the incidence of major cardiovascular events has classically required the evaluation of major 'hard' end points. In view of the long natural history of hypertension, however, it appears very useful to monitor modifications in measurable 'intermediate' end points or 'disease markers'. This approach may provide more accurate individual risk stratification and a better evaluation of the efficacy of a given treatment in preventing or modifying the course of target organ damage. This may represent a valuable and affordable strategy in clinical practice allowing the evaluation of both patient prognosis and the effectiveness of antihypertensive treatment over time.

Impact of telmisartan versus ramipril on renal endothelial function in patients with hypertension and type 2 diabetes

OBJECTIVE

One of the earliest signs of vascular change is endothelial dysfunction, which is also known to provoke albuminuria and to predict cardiovascular prognosis. The aim of this study was to analyze the effects of renin-angiotensin system (RAS) blockade on renal endothelial function.

RESEARCH DESIGN AND METHODS

In a multicenter, prospective, double-blind, forced-titration, randomized study, 96 patients with type 2 diabetes, hypertension, glomerular filtration rate >80 ml/min, and normo- or microalbuminuria were treated once daily with 40/80 mg telmisartan or 5/10 mg ramipril for 9 weeks.

RESULTS

The mean +/- SE fall in renal plasma flow (RPF) in response to intravenous N(G)-monomethyl-L-arginine (L-NMMA), reflecting the magnitude of nitric oxide (NO) activity, increased with telmisartan from 71.9 +/- 9.0 ml/min before therapy to 105.2 +/- 9.7 ml/min at the end of treatment (P < 0.001). With ramipril, RPF response to L-NMMA increased from 60.1 +/- 12.2 to 87.8 +/- 9.2 ml/min (P = 0.018). The adjusted difference between treatments was -17.1 +/- 13.7 ml/min (P = 0.214). In accordance, telmisartan increased RPF at rest (i.e., without L-NMMA) from 652.0 +/- 27.0 to 696.1 +/- 31.0 ml/min (P = 0.047), whereas ramipril produced no significant changes in RPF. The more the basal NO activity improved, the greater was the vasodilatory effect on renal vasculature (r = 0.47, P < 0.001).

CONCLUSIONS

In patients with type 2 diabetes, telmisartan and ramipril both increased NO activity of the renal endothelium significantly, which in turn may support the preservation of cardiovascular and renal function.

Complications of hypertension and the role of angiotensin receptor blockers in hypertension trials

Hypertension is a high-prevalence disease that may affect several organs. In recent years, data have accumulated indicating that angiotensin II receptor blockers (ARBs) may have a supplementary effect beyond lowering blood pressure. The aim of this review is to evaluate the impact of ARBs on the most important complications of hypertension--heart, cerebrovascular and renal diseases, and metabolic complications--based on the findings from large clinical hypertension trials. The results may indicate that ARBs have a superior effect compared with placebo or other antihypertensive drugs in order to prevent left ventricular hypertrophy, atrial fibrillation, stroke, renal disease and diabetes mellitus, while there appears to be no blood pressure-independent superior effect of ARBs regarding prevention of myocardial infarction or heart failure.

Microalbuminuria: what is it? Why is it important? What should be done about it? An update

Microalbuminuria (MA) is defined as a persistent elevation of albumin in the urine of >30 to <300 mg/d (>20 to <200 microg/min). Use of the morning spot urine test for albumin-to-creatinine measurement (mg/g) is recommended as the preferred screening strategy for all patients with diabetes and with the metabolic syndrome and hypertension. MA should be assessed annually in all patients and every 6 months within the first year of treatment to monitor the impact of antihypertensive therapy. It is an established risk marker for the presence of cardiovascular disease and predicts progression of nephropathy when it increases to frank microalbuminuria>300 mg/d. Data support the concept that the presence of MA is the kidney's warning that there is a problem with the vasculature. The presence of MA is a marker of endothelial dysfunction and a predictor of increased cardiovascular risk. MA can be reduced, and progression to overt proteinuria prevented, by aggressive blood pressure reduction, especially with a regimen based on medications that block the renin-angiotensin-aldosterone system, and control of diabetes. The National Kidney Foundation recommends that blood pressure levels be maintained at or below 130/80 mm Hg in anyone with diabetes or kidney disease.

Blood pressure reduction and antihypertensive medication use in the losartan intervention for endpoint reduction in hypertension (LIFE) study in patients with hypertension and left ventricular hypertrophy

OBJECTIVE

To compare blood pressure response and antihypertensive medication use visit-by-visit from baseline in patients receiving losartan-based or atenolol-based therapy in the LIFE study.

RESEARCH DESIGN

LIFE was a randomized, double-blind trial comparing losartan-based and atenolol-based treatment regimens on the primary composite endpoint of death, myocardial infarction (MI), or stroke in 9193 patients aged 55-80 years with hypertension and left ventricular hypertrophy. Systolic and diastolic, pulse, and mean arterial pressures, blood pressure responder rates, distribution of open-label antihypertensive agents utilized, and the proportion of patients on randomized treatment were determined for each group at each clinic visit over a follow-up period of at least 4 years.

RESULTS

Overall blood pressure reductions were comparable in the losartan-based and atenolol-based treatment groups. The mean reductions in sitting trough systolic and diastolic blood pressures from baseline to the end of follow-up (or last visit before a primary endpoint event) were 30.2/16.6 mmHg in the losartan group and 29.1/16.8 mmHg in the atenolol group. The time-averaged difference in overall mean arterial pressure was similar between groups. The proportion of patients on individual dose combinations varied visit by visit but was generally comparable between groups. During the entire study, 56% (2579/4605) of losartan-treated patients received at least one dose of the combination of losartan 100 mg plus hydrochlorothiazide 12.5 mg and 51% of atenolol-treated patients received 100 mg of atenolol plus hydrochlorothiazide 12.5 mg at some time during the study.

CONCLUSIONS

Differences in blood pressure or distribution of add-on medications between treatment groups were not evident in the LIFE trial and, thus, cannot account for the observed outcome difference in the primary endpoint of risk reduction of the composite of cardiovascular death, stroke and MI favoring losartan.