The concept of the cardio-renal continuum proposes that cardiovascular (CV) and renal disease reinforce each other, with deteriorations in either system having an effect on the other. As the early stages of the cardio-renal continuum are not associated with symptoms, the early assessment of respective risk factors (such as dyslipidaemia, hypertension, diabetes, visceral obesity, smoking) is critical. Microalbuminuria is an early, sub-clinical sign of target-organ damage and is correlated with specific cardio-renal outcomes.The interrelated nature of the different elements of the cardio-renal continuum also has implications for treatment strategies. Intensified, multifactorial treatment targeted at hyperglycaemia, hypertension and dyslipidaemia can lower the risk of both CV and renal disease.Reference:Dzau VJ, et al. The cardiovascular disease continuum validated: clinical evidence of improved patient outcomes: part I: Pathophysiology and clinical trial evidence (risk factors through stable coronary artery disease). Circulation. 2006;114:2850–70.
The normal physiological role of the renin-angiotensin-aldosterone system (RAAS) is to maintain the sodium balance in the body and it, therefore, plays a major role in blood pressure (BP) control. If it is inappropriately activated, hypertension may result.The RAAS is activated when renin is released in response to reduced BP or sodium concentrations.Renin is an enzyme that converts angiotensinogen into angiotensin I, which is in turn converted by angiotensin-converting enzyme (ACE) into the hormone angiotensin II, the active form.Angiotensin II binds to an angiotensin II receptor in the muscle cells of blood-vessel walls, causing these cells to contract and hence narrowing of the vessels.Production of angiotensin II, increases systemic BP as a consequence of vasoconstriction of arterioles and, over several days, also releases aldosterone by the adrenal cortex. Aldosterone stimulates water retention via reabsorption of sodium and excretion of potassium from the nephron.It is well established that activation of the RAAS, through the actions of angiotensin II on the angiotensin II type 1 (AT1) receptor, plays a major role in endothelial dysfunction. Pathways include the induced synthesis and release of the inflammatory cytokine interleukin 6 (IL-6), increased generation of reactive oxygen species, and induction of adhesion molecules. In relation to albuminuria, angiotensin II has been shown to directly affect the integrity of the ultrafiltration barrier by decreasing the synthesis of negatively charged proteoglycans. It also stimulates proliferation of mesangial and glomerular endothelial cells, which may reduce the glomerular filtration surface and therefore the rate of filtration. In people with diabetes, increased activity of the RAAS has been observed in the circulation and in various organs.-In those with diabetes and microalbuminuria, inhibition of the RAAS with an angiotensin receptor blocker (ARB) has been shown to reduce markers of low-grade inflammation (notably IL-6) that may lead to endothelial damage in association with changes in albumin excretion.RAAS-inhibiting drugs were originally developed to control hypertension and thereby reduce cardiovascular risk. However, they are also nephroprotective, slowing down progression to end-stage renal disease. Indeed, blockade of the RAAS provides nephroprotection beyond the effects of BP-lowering alone. Reference:Basi S and Lewis JB. Microalbuminuria as a target to improve cardiovascular and renal outcomes. Am J Kidney Dis. 2006;47(6):927-46.
Both microalbuminuria (MAU) and estimated glomerular filtration rate (eGFR) are independent predictors of a progressive loss of renal function. GFR estimation using equations may also have a certain degree of inaccuracy; however, the use of the Cockcroft-Gault equation, corrected for ideal body weight, provides an acceptable way to estimate GFR in the clinical setting. When MAU is present and detectable, the phase of glomerular hyperfiltration shifts to that of a progressive loss in renal function. At this time, GFR typically is normal, elevated or only modestly impaired (stage 1 or 2 CKD). Hence, it is less appropriate to measure eGFR to detect early risk of cardiovascular events in the general population.References:Ninomiya T, Perkovic V, de Galan BE, Zoungas S, Pillai A, Jardine M, Patel A, Cass A, Neal B, Poulter N, Mogensen CE, Cooper M, Marre M, Williams B, Hamet P, Mancia G, Woodward M, Macmahon S, Chalmers J; ADVANCE Collaborative Group. Albuminuria and kidney function independently predict cardiovascular and renal outcomes in diabetes. J Am Soc Nephrol. 2009;20(8):1813-21. Epub 2009 May 14.De Jong PE, Curhan GC. Screening, monitoring, and treatment of albuminuria: public health perspectives J Am Soc Nephrol. 2006;17:2120-6.
In individuals with microalbuminuria (MAU), the main aim of treatment is to manage the associated risk factors. Management of these factors individually is beneficial, hence they should be treated aggressively. Cross-sectional studies have demonstrated that the primary risk factors related to MAU are high blood pressure and diabetes, leading to renal disease. Obesity and smoking, however, have also been implicated as determinants of MAU in some studies. Secondary risk factors for MAU include pathophysiological changes in the kidneys, such as acute or focal glomerulonephritis, amyloidosis, and thickening of the glomerular and tubular basal membrane with progressive mesangial expansion which may lead to end-stage renal disease. Factors such as minimal-change disease may predispose the kidney to nephrotic syndrome and loss of renal function which precedes the development of MAU. Increased dietary protein intake also seems to be associated with the presence of higher urinary albumin excretion values. In addition, salt sensitivity in high-risk patients may cluster with other factors that are likely to play an important role in the pathogenesis of MAU.Reference:Zelmanovitz T, Gerchman F, Balthazar AP, et al. Diabetic nephropathy. Diabetol Metab Syndr. 2009;1(1):10.
Treatment guidelines recommend the frequency at which high-risk patients should be screened for microalbuminuria (MAU).The current ESH-ESC guidelines, revised in 2009, consider all people with hypertension (SBP 140 mmHg or DBP 90 mmHg and all individuals with the metabolic syndrome and high-normal blood pressure (SBP 130-139 mmHg or DBP 85-89 mmHg) to be at high-risk, requiring routine assessment for subclinical organ damage (including assessment of MAU) at screening for cardiovascular risk and during treatment. Patients should be assessed routinely using:Serum creatinineEstimated creatinine clearance Urinalysis (complemented by MAU via dipstick test and microscopic examination)Electrocardiogram.MAU should also be assessed during treatment as well as during screening of patients.References:Mancia G, De Backer G, Dominiczak A, Cifkova R, Fagard R, Germano G, et al.2007 ESH-ESC Practice Guidelines for the Management of Arterial Hypertension: ESH-ESC Task Force on the Management of Arterial Hypertension. J Hypertens. 2007;25(9):1751-62.Mancia G, Laurent S, Agabiti-Rosei E, Ambrosioni E, Burnier M, Caulfield MJ, et al. Reappraisal of European guidelines on hypertension management: a European Society of Hypertension Task Force document. J Hypertens. 2009;27(11):2121-58.
Three large-scale, population-based studies – two in Europe (PREVEND and the HUNT study) and one in the United States (NHANES III) – reported similar prevalence data for microalbuminuria (MAU) in the general population, with or without the inclusion of individuals with concomitant diabetes and/or hypertension.In study populations that included participants with diabetes or hypertension, MAU was present in 7.2−7.8% of individuals. In those with neither concomitant diabetes or hypertension, prevalence was 5.1−6.6%. The majority of the study population were from the advancing middle-age group in all three studies. A further subanalysis of the PREVEND study showed that restricting screening to high-risk groups (e.g. individuals with hypertension, diabetes, CVD and the elderly) failed to identify 45% of individuals with MAU and macroalbuminuria.References:Hillege HL, Janssen WM, Bak AA, et al. Microalbuminuria is common, also in a non-diabetic, non-hypertensive population, and an independent indicator of cardiovascular risk factors and cardiovascular morbidity. J Intern Med. 2001;249:519-56. Jones CA, Francis ME, Eberhardt MS, et al. Microalbuminuria in the US population: third National Health and Nutrition Examination Survey. Am J Kidney Dis. 2002;39(3):445-59.Romundstad S, Holmen J, Kvenild K, et al. Microalbuminuria and all-cause mortality in 2,089 apparently healthy individuals: A 4.4-year follow-up study The Nord-Trondelag Health Study (HUNT), Norway. Am J Kidney Dis. 2003;42:466-73.Menne J, Chatzikyrkou C, Haller H. Microalbuminuria as a risk factor: the influence of renin-angiotensin system blockade. J Hypertens. 2010;28(10):1983-94.
Subgroup analyses of large-scale, population-based studies have found the prevalence of microalbuminuria (MAU) in people with diabetes (type 1 or type 2) to be in the range of 16−29% in European and US populations in the PREVEND Study and NHANES III. The DEMAND Study was a global, clinic/medical centre-based study, conducted mainly in a primary-care setting. Patients aged 18−80 years with type 2 diabetes without known nephropathy were randomly screened for micro- and macro-albuminuria (urinary albumin/creatinine ratio 30−299 mg/g and ≥300 mg/g respectively). Overall, 39% of subjects had MAU and 10% had macroalbuminuria.References:Hillege HL, Janssen WM, Bak AA, et al. Microalbuminuria is common, also in a nondiabetic, nonhypertensive population, and an independent indicator of cardiovascular risk factors and cardiovascular morbidity. J Intern Med. 2001;249:519-56.Jones CA, Francis ME, Eberhardt MS, et al. Microalbuminuria in the US population: third National Health and Nutrition Examination Survey. Am J Kidney Dis. 2002;39(3):445-59.Parving HH, Lewis JB, Ravid M, et al. Prevalence and risk factors for microalbuminuria in a referred cohort of type II diabetic patients: a global perspective. Kidney Int. 2006;69(11):2057-63.Tapp RJ, Shaw JE, Zimmet PZ, et al. Albuminuria is evident in the early stages of diabetes onset: results from the Australian Diabetes, Obesity, and Lifestyle Study (AusDiab). Am J Kidney Dis. 2004;44(5):792-8.
The Australian Diabetes, Obesity and Lifestyle (AusDiab) study was a population-based study of 11,247 individuals aged ≥25 years who were randomly selected from urban and rural areas of Australia. All participants were screened for diabetes, microalbuminuria (MAU; urinary albumin:creatinine ratio 22−20 mg/g in males and 31−220 mg/g in females) and macroalbuminuria (urinary albumin:creatinine ratio ≥220 mg/g).In participants with diabetes (known and newly-diagnosed type 1 or type 2 diabetes; n=913), MAU was present in 21.0% and macroalbuminuria in 4.3% of individuals, respectively.Analysis of data from the complete general population sample (excluding those with type 1 diabetes; n=34) also showed increased prevalence of albuminuria with increasing glucose intolerance. Impaired fasting glucose, as well as type 2 diabetes, was associated with a significant increased risk of albuminuria after adjusting for age, sex and other known albuminuria risk factors.Reference:Tapp RJ, Shaw JE, Zimmet PZ, et al. Albuminuria is evident in the early stages of diabetes onset: results from the Australian Diabetes, Obesity, and Lifestyle Study (AusDiab). Am J Kidney Dis. 2004;44(5):792-8.
This slide lists the key clinical studies evaluating the predictive value of MAU on CV risk, using MAU as a predictor.
This slide lists the key clinical studies that have evaluated the predictive value of the change in microalbuminuria (MAU) on cardiovascular and renal risk.
As well as in individuals with diabetes and hypertension, MAU also seems to be associated with all-cause and cardiovascular (CV) mortality in the general population.This observation was originally reported in the ‘Prevention of Renal and Vascular End Stage Disease (PREVEND)’ study, which was designed to investigate the natural course of increased levels of urinary albumin and the relationship with renal and CV events in the general population. The figure on the slide demonstrates that the association between increasing albuminuria and renal events is similar to that of albuminuria and CV events, providing compelling evidence that MAU is a strong predictor of CV mortality, independent of other CV risk factors.Reference:Gansevoort RT, de Jong PE. The case for using albuminuria in staging chronic kidney disease. J Am Soc Nephrol. 2009;20(3):465-8.
The Losartan Intervention For Endpoint reduction in hypertension (LIFE) substudy investigated whether urine albumin:creatinine ratio (UACR) and left ventricular (LV) mass – both being associated with diabetes and increased blood pressure – were independent predictors of cardiovascular (CV) events in patients with hypertension.It was found that UACR and LV mass predicted the composite endpoint (CV death, nonfatal stroke or nonfatal myocardial infarction) as well as CV death, independently of each other. The fact that UACR and LV mass supplemented each other in the prediction of CV endpoints, supports the hypothesis that albuminuria and LV hypertrophy, although both reflecting subclinical hypertensive target organ damage, may be markers of damage in different parts of the CV system. Albuminuria may not only reflect glomerular damage but also systemic damage of the small arteries and capillaries, whereas high LV mass reflects damage of the heart, probably in the large arteries. Reference:Olsen MH, Wachtell K, Bella JN, Palmieri V, Gerdts E, Smith G, et al. Albuminuria predicts cardiovascular events independently of left ventricular mass in hypertension: a LIFE substudy. J Hum Hypertens. 2004;18(6):453-9.
In a large community-based cohort study of over 920,000 adults receiving routine clinical care, the risk of adverse renal outcomes increased with the presence and severity of proteinuria. In this study, the prognosis associated with a given level of estimated glomerular filtration rate (eGFR) varied considerably based on the presence and severity of proteinuria. In fact, patients with heavy proteinuria, but without overtly abnormal eGFR, appeared to have worse clinical outcomes than those with moderately reduced eGFR without proteinuria. In addition, adjusted mortality rates were more than 2-fold higher among individuals with heavy proteinuria (whether determined by urine dipstick or UACR) and eGFR of 60 ml/min/1.73 m2 or greater, compared with those with eGFR of 45–59.9 ml/min/1.73 m2 and normal protein excretion. Furthermore, each 10-fold increase in UACR was associated with a 1.92-increased risk for the initiation of renal replacement therapy (signalling end-stage renal disease) and a 1.76-fold increased risk of doubling of serum creatinine. Interestingly, the adverse prognosis associated with proteinuria was seen at all levels of eGFR. This study demonstrates that the risks of mortality, myocardial infarction, and progression to kidney failure associated with a given level of eGFR are independently increased in patients with higher levels of proteinuria. Thus, the status of albuminuria is a more sensitive predictor of risk than eGFR.Reference:Hemmelgarn BR, Manns BJ, Lloyd A, et al. for the Alberta Kidney Disease Network. Relation between kidney function, proteinuria, and adverse outcomes. JAMA. 2010;303(5):423-9.
This slide lists the key clinical studies that have evaluated the predictive value of the change in microalbuminuria (MAU) on cardiovascular and renal risk.
The figure on this slide shows the cardiovascular (CV) prognosis (CV event or congestive heart failure) following reduction of microalbuminuria in individuals with type 2 diabetes in the Reduction in Endpoints in Non–insulin dependent diabetes mellitus with the Angiotensin II Antagonist Losartan (RENAAL) study – a double-blind, randomised trial in 1513 type 2 diabetic patients with nephropathy. Both the high (3.0 g/g) and middle (1.53.0 g/g) groups show significantly more cardiovascular events.In this study, albuminuria was the strongest risk marker for CV events in type 2 diabetic subjects with nephropathy. Suppression of albuminuria was found to be the strongest predictor oflong-term protection from CV events, underlying that treatment reduction lowers the risk for CV endpoints.ReferenceDe Zeeuw D, et al. Kid Int. 2004;65:2309-20.
Increasing albuminuria is associated with an increased risk of cardiovascular (CV) events.Previously the LIFE Study showed that the angiotensin II receptor blocker (ARB), losartan, prevented more CV morbidity and mortality than the beta-blocker, atenolol, in patients with hypertension and left ventricular hypertrophy (a known predictor of CV events).A post-hoc analysis of the relationship between baseline albuminuria and the effects of treatment on CV events showed that the benefit of losartan compared with atenolol tended to be more pronounced in patients with above median albuminuria at baseline.During the study, there was a significantly greater decrease in albuminuria with losartan versus atenolol from baseline; this was reported to explain one-fifth of the reduction in CV events with losartan compared with atenolol.The slide shows that the risk of a subsequent CV endpoint increased 3- to 4-fold from the lowest (≤0.5 mg/mmol) to the highest (>3 mg/mmol) strata. The number of at-risk patients in the strata indicates that patients tended to shift from a higher level of UACR at baseline to a lower level at Years 2 and 4. This implies that when UACR is reduced from the >3 mg/mmol level to the ≤0.5 mg/mmol level, the associated risk is reduced accordingly.Reference:Ibsen H, Olsen MH, Wachtell K, et al. Reduction in albuminuria translates to reduction in cardiovascular events in hypertensive patients: losartan intervention for endpoint reduction in hypertension study. Hypertension. 2005;45(2):198-202.
Few data are available to confirm whether changes in albuminuria over time translate to changes in cardiovascular (CV) risk.The Losartan Intervention For Endpoint reduction in hypertension (LIFE) study examined whether changes in albuminuria during 4.8 years of antihypertensive treatment were related to changes in risk in 8,206 patients with hypertension and left ventricular hypertrophyUrinary albumin:creatinine ratio (UACR) was measured at baseline and annually. Time-varying albuminuria was closely-related to risk for the primary composite endpoint (i.e. when UACR decreased during treatment, risk was reduced accordingly). When the population was divided according to median baseline value (1.21 mg/mmol) and median Year 1 UACR (0.67 mg/mmol), risk increased stepwise and significantly for the primary composite end point from those with low baseline/low year 1 (5.5%), to low baseline/high year 1 (8.6%), to high baseline/low Year 1 (9.4%), and to high baseline/high year 1 (13.5%) values. Similar significant, stepwise increases in risk were seen for the components of the primary composite endpoint (CV mortality, stroke, and myocardial infarction). Changes in UACR during antihypertensive treatment over time translated to changes in risk for CV morbidity and mortality was not explained by in-treatment level of blood pressure. The authors proposed that monitoring of albuminuria should be an integrated part of the management of hypertension. If albuminuria is not reduced by the patient’s current antihypertensive and other treatment, further intervention directed toward blood pressure control and other modifiable risks should be considered. Reference: Ibsen H, Olsen MH, Wachtell K, et al. Reduction in Albuminuria Translates to Reduction in Cardiovascular Events in Hypertensive PatientsLosartan Intervention for Endpoint Reduction in Hypertension Study. Hypertension.2005;45:198-202.
This slides shows the change in microalbuminuria (MAU) as a predictor of cardiovascular (CV) and renaloutcomes in patients with vascular disease in the ONTARGET studyAnalyses were performed (N=23,480) and adjusted for age, gender, BMI, smoking, alcohol consumption, eGFR, plasma glucose, blood pressure (BP) and HR at baseline, BP change within 2 years and baseline albuminuria.The risk of CV and renal outcomes increases significantly if MAU is increased and is decreases if MAU is reduced. Reference:Schmieder R, Mann, JFE, Schumacher H, et al. Changes in albuminuria predict mortality and morbidity in patients with vascular disease. JASN 2011; In press.
This slides shows the change in microalbuminuria (MAU) as a predictor of all-cause mortality in patients with vascular disease in the ONTARGET studyAnalyses were performed (N=23,480) and adjusted for age, gender, BMI, smoking, alcohol consumption, eGFR, plasma glucose, blood pressure (BP) and HR at baseline, BP change within 2 years and baseline albuminuria.The risk of all-cause mortality increases significantly if MAU is increased and is decreases if MAU is reduced. Reference:Schmieder R, Mann, JFE, Schumacher H, et al. Changes in albuminuria predict mortality and morbidity in patients with vascular disease. JASN 2011; In press.
This slide summarises the main conclusions of this section.
The large-scale Bergamo Nephrologic Diabetes Complications Trial (BENEDICT) study was a multicentre double-blind, randomised trial designed to assess whether ACE inhibitors and non-dihydropyridine calcium-channel blockers, alone or in combination, prevent microalbuminuria (MAU) in individuals with hypertension, type 2 diabetes (T2D), and normal urinary albumin excretion.Persistent MAU developed in 17 of the 300 participants receiving trandolapril plus verapamil (5.7%), compared with 30 of 300 participants receiving placebo (10.0%) – see the graph on the slide. Kaplan–Meier curves for these two treatment groups clearly separated at three months. The estimated acceleration factor when controlled for predefined baseline variables was 0.39 (95% confidence interval, 0.19 to 0.80; p=0.01) in the trandolapril-plus-verapamil group as compared with the placebo group. Thus, the combination of trandolapril and verapamil significantly delayed the onset of MAU, by a factor of 2.6.Additionally, the primary outcome was reached in 6.0% of participants receiving trandolapril alone, 11.9% of participants receiving verapamil alone, and 10.0% of participants receiving placebo. Trandolapril alone, delayed the onset of MAU by a factor of 2.1. Thus, in participants with T2D and hypertension but with normoalbuminuria, the use of trandolapril plus verapamil and trandolapril alone reduces the incidence of MAU to a similar extent. The effect of trandolapril plus verapamil and trandolapril alone in preventing MAU exceeded expectations based on changes in blood pressure alone.Reference:Ruggenenti P, Fassi A, Ilieva AP, Bruno S, Iliev IP, Brusegan V, et al. Preventing microalbuminuria in type 2 diabetes. N Engl J Med. 2004;351(19):1941-51.
This slide summarises the main conclusions of this section.
This slide summarises the key clinical studies conducted to date to evaluate prevention and treatment of different levels of albuminuria and kidney disease.
Several treatments can significantly ameliorate the course of nephropathy in people with diabetes and microalbuminuria (MAU). Importantly, the earlier that treatment is initiated the greater the benefit observed. The joint European Society of Hypertension/European Society of Cardiology (ESH/ESC) guidelines recommend that patients with hypertension and microalbuminuria (MAU) should receive angiotensin converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) as first-line treatment, due to their inherent renoprotective effects.1The American Diabetes Association recommends ACE inhibitors or ARBs as the treatments of choice for nephropathy in people with diabetes.2 References: Mancia G, De Backer G, Dominiczak A, et al. 2007 Guidelines for the Management of Arterial Hypertension: The Task Force for the Management of Arterial Hypertension of the European Society of Hypertension (ESH) and of the European Society of Cardiology (ESC). J Hypertens. 2007;25(6):1105-87. Nathan DM, Buse JB, Davidson MB, et al. Medical management of hyperglycaemia in type 2 diabetes: a consensus algorithm for the initiation and adjustment of therapy. A consensus statement of the American Diabetes Association and the European Association for the Study of Diabetes. Diabetes Care. 2009;32:193-203.
This slide summarises the main conclusions of this section.
The evolving role of Microalbuminuria (MAU)MAU as an early and reliable marker of organ damageand a strong predictor of cardiovascular risk
Pathologic Processes Leading to Glomerular Injury and Proteinuria Glucose Urinary proteinGlycoxidation(glycation) AGEs =angiotensin AT1 receptor Increased glomerular Efferent pressure arteriolar constriction Ang II Ang II
Pathways Leading To Progressive Renal Failure Renal injury Renal growth factor & cytokine activation Systemic Nephron mass hypertension Filtration of plasma Glomerular hypertension proteins (Proteinuria) Transdifferentiation of Progressive Loss ofrenal cells to fibroblast Filtration Surface Area phenotype Proximal tubule protein uptake Influx of monocytes Hyperlipidemia and macrophages GFR Renal microvascular Fibrogenesis Renal scarring injuryBrenner BM, Keane WF. 2001.
Angiotensin II and thrombospodin(TSP1)both can stimulate the production oftransforming growth factor-b (TGF-) by tubuloepithelial cells and fibroblasts. TGF- TGF- plays a key role in extracellular matrix formation in mesangium and interstitium that leads to fibrosis and loss of nephron units
• O2Ang II bFGF PDGF TSP1 TGF- • O2 TGF- plays a key role in extracellular matrix formation in mesangium and interstitium that leads to fibrosis and loss of nephron units
Aldosterone Promotes Renal Fibrosis by Multiple Mechanisms Angiotensin II Adrenal Vascular AldosteronePAI-1 Stimulates Nitric oxide Inhibits synthesis Na+ influx into VSMC Fibroblast collagen Norepinephrine synthesis uptake AT1R binding into VSMC of Ang II
MAU in the cardio-renal continuum: A strong and independent risk factor for cardio-renal disease Clinical Disease Established Diabetes Subclinical Claudication Recent Organ Damage Diabetes Cardiovascular Angina Event LVH Proteinuria TIA IMT Myocardial Risk End Organ Moderate Infarction Factors Failure Renal Disease Stroke Mild Renal Microalbuminuria End-Stage Chronic Disease Renal Disease Heart Failure (MAU) Hypertension Diabetes/Metabolic Syndrome Increased LDL Smoking IMT = intima media thickness; LVH = left ventricular hypertrophy; TIA = transient ischaemic event; LDL = low-density lipoprotein; CV = cardiovascular The cardio-renal continuum is the interrelated progression of CV and renal disease MAU is an early integrated sign of target organ damageDzau VJ, et al. Circulation. 2006;114:2850-70.
Albuminuria: The role of the RAAS Evidence points to a major role for the RAAS in pathophysiological changes that lead to progressive renal and cardiovascular disease Renin inhibitor Angiotensinogen Ang I Renin ACEIs ACE Compensatory Ang II feedback ARBs AT1 receptor Aldosterone Aldosterone Reactive oxygen species inhibitor Inflammatory mediators (e.g. IL-6) Adhesion molecules (e.g. IL-6) Cellular growth and apoptosis Endothelial dysfunction ALBUMINURIA Ang = angiotensin; AT1 = angiotensin II type 1; ACEI = ACE inhibitor; ARB = AT receptor blocker; IL-6 = interleukin 6; ICAN-1 = intercellular adhesion molecule.Basi S , et al. Am J Kidney Dis. 2006;47(6):927-46.
MAU: an important and sensitive marker of early kidney dysfunction Albumin is one of the smallest plasma proteins and accounts for ~60% of total plasma protein1 Clinical significance of albuminuria Albumin is the first to appear in the urine during kidney dysfunction2 MAU occurs in the earliest stages of kidney disease and reflects vascular damage3 MAU can indicate dysfunction, even during early chronic kidney disease (CKD), while eGFR may remain within the normal range21. Gekle M. News Physiol Sci. 1998;13:5-11. 2. Levey AS. Ann Intern Med. 2003;139:137-47. 3. Cerasola G, et al. J Hypertens. 2010 Sep 16.
Measuring MAU: Sampling Methods for sampling/measuring albumin:1 Measures Practicalities Recommended, most practical, reliable Morning spot-urine sample (mg/l) and easy to use method Still gold standard but not practical 24-hour urine collection (mg/24h) and subject to collection errors Timed overnight urine collection (µg/min) Easy but not practical A urine dipstick test in a morning spot-urine sample is the recommended method for initial screening21. De Jong PE, Curhan GC. J Am Soc Nephrol. 2006;17:2120-6. 2. Busby DE , et al. J Clin Hypertens 2004;6(11 suppl. 3):8-12.
MAU is emerging as an early and more sensitive marker than eGFR MAU eGFR CV risk factors Both MAU and eGFR are independent predictors of a progressive loss in renal function1 When MAU is present and detectable, GFR is typically normal, elevated or only modestly impaired (stage 1 or 2 CKD)2 MAU = microalbuminuria; CV = cardiovascular; eGFR = estimated glomerular filtration rate; CKD = chronic kidney disease.1. Ninomiya T, et al. J Am Soc Nephrol. 2009;20(8):1813-21. 2. De Jong PE, et al. J Am Soc Nephrol. 2006;17:2120-6.
Conventional threshold levels for MAU using different methods 24-hour Overnight (First morning void) spot urine urinary urinary albumin albumin Albumin* Urinary albumin/creatinine ratio (UACR) excretion excretion (mg/L) (mg/24 h) (µg/min) Gender mg/mmol mg/g M 1.25 to <2.5 10 to <20 High normal 15 to <30 10 to <20 10 to <20 F 1.75 to <3.5 15 to <30 Micro- M 2.5 to <25 20 to <200 albuminuria 30 to <300 20 to <200 20 to <200 F 3.5 to <35 30 to <300 (MAU)*Measured, for example, using dipstick test. MAU is defined as a spot urinary albumin measurement of 20 to <200 mg/lDe Jong PE, Curhan GC. J Am Soc Nephrol. 2006;17:2120-6.
Who should be screened? People at risk of MAU In individuals with MAU, the aim of treatment is to manage the risk factors Major risk factors for MAU Hypertension* Diabetes Obesity Gender and age Family history of chronic kidney disease Smoking Genetic factors * Primary risk factors Management of these risk factors individually is beneficial, hence they should be treated aggressivelyZelmanovitz T, et al. Diabetol Metab Syndr. 2009;1(1):10.
When to screen? Guideline recommendations for MAU testing Organisation Patient Group Frequency ESH-ESC All people with: • Routine assessment at screening for Guidelines CV risk and during treatment 2009 Reappraisal • Hypertension (SBP 140 mmHg or DBP • Patient should be assessed routinely 90 mmHg) using: – Serum creatinine • Metabolic syndrome & – Estimated creatinine clearance – Urinalysis (complemented by MAU via high-normal BP (SBP 130–139 dipstick test and microscopic examination) mmHg or DBP 80–85 mmHg) – Electrocardiogram • MAU should be examined during treatment as well as during screeningESH/ESC = European Society of Hypertension/European Society of Cardiology; SBP = systolic blood pressure; DBP = diastolic blood pressure;CV = cardiovascular; MAU = microalbuminuria; BP = blood pressure. Current ESH-ESC guidelines recommend routine testing for MAU in patients with hypertension and in metabolic syndrome with high-normal BP1. Mancia G, et al. J Hypertens. 2007;25:1105-87. 2. Mancia G, et al. J Hypertens. 2009;27:2121-58.
Prevalence of MAU in the general population, and in diabetic and hypertensive patients
MAU* is present in ~5−7% of the general population† PREVEND (Netherlands)1 n=40,619 NHANES III (USA)2 n=22,244 HUNT (Norway)3 n=2,089 10 in general population (%) 7.8 8 7.2 Prevalence of MAU 6.6 6 5.1 5.2 4 2 0 General population Non-diabetic, non-hypertensive‡ * Morning urinary albumin 20–200 mg/L in the PREVEND Study, urinary albumin/creatinine ratio 30–299 mg/g in NHABES III, and urinary albumin/creatinine ratio >22 µg in the HUNT Study. † Aged 28–75 years in the PREVEND Study, ≥6 years in NHANES III, and ≥20 years in the HUNT Study. ‡ In NHANES III, the non-diabetic, non-hypertensive cohort also excluded subjects with cardiovascular disease or elevated serum creatinine levels. Restricting screening to high-risk groups in PREVEND (e.g. hypertension, diabetes, CVD and the elderly) failed to identify 45% of individuals with MAU and macroalbuminuria41. Hillege HL, et al. J Intern Med. 2001;249:519-26. 2. Jones CA, et al. Am J Kidney Dis. 2002;39(3):445-59. 3. Romundstad S, et al. Am J Kidney Dis. 2003;42:466-73. 4. Menne J, et al.J Hypertens. 2010;28(10):1983-94.
MAU* is present in ~16−40% of the population with diabetes†‡ 45 in population with diabetes (%) 39.0 40 35 Prevalence of MAU 28.8 30 25 21.0 20 16.4 15 10 5 0 PREVEND NHANES III DEMAND AusDiab (Netherlands)1 (US)2 (Global)3 (Australia)4 * Morning urinary albumin 20–200 mg/L in the PREVEND Study, urinary albumin/creatinine ratio 22–220 mg/g in males and 31–220 mg/g in females in the AusDiab study, urinary albumin/creatinine ratio 31–299 mg/g in NHANES III and the DEMAND Study. † Aged 28–75 years in the PREVEND Study, ≥6 years in NHANES III, and 18–80 years in the DEMAND Study. ‡ PREVEND, AusDiab and NHANES III were true population based studies; DEMAND studied a clinical /medical centre-based referred cohort (mainly in a primary-care setting). The DEMAND study, in patients with type 2 diabetes and no known nephropathy, identified MAU in 39% and macroalbuminuria in 10% of participants, respectively31. Hillege HL, et al. J Intern Med. 2001;249:519-26. 2. Jones CA et al. Am J Kidney Dis. 2002;39(3):445-59. 3. Parving HH, et al. Kidney Int. 2006;69(11):2057-63. 4. Tapp RJ, Am JKidney Dis. 2004;44(5):792-8.
Hypertension and glucose status are associated with increased risk for MAU: The AusDiab Study No HTN HTN 30 n=10,596 patients 25.4 Proportion with MAU (%) 25 20 18.3 13.8 15 10.3 10 8.3 3.7 4.8 5 2.5 0 DM IGT IFG NG AusDiab = Australian Diabetes, Obesity and Lifestyle; MAU = microalbuminuria; DM = diabetes mellitus; IGT = impaired glucose tolerance; IFG = impaired fasting glucose; NG = normal glucose; HTN = hypertension; T2D = type 2 diabetes. Impaired fasting glucose − as well as type 2 diabetes − is associated with a significantly increased risk of albuminuria after adjusting for age, sex and other known albuminuria risk factorsTapp RJ, et al. Am J Kidney Dis. 2004;44(5):792-8.
Albuminuria – a marker of renal damage – is associated with increased CV morbidity and mortality The UKPDS Annual transition rates through stages of albuminuria in patients with type 2 diabetes No nephropathy 1.4% 2.0% (1.3-1.5%) (1.9-2.2%) Microalbuminuria (MAU) Death 3.0% 2.8% (2.6-3.4%) (2.5-3.2%) Macroalbuminuria 4.6% 2.3% (3.6-5.7%) (1.5-3.0%) ↑ Plasma creatinine or renal replacement therapy 19.2% (14.0-24.4%)Data from the United Kingdom Prospective Diabetes Study (UKPDS). Data presented as annual transition rates with 95% confidence intervals. Adler A, et al. Kidney Int. 2003;63:225-32.
Albuminuria indicates vascular damage at different stages of renal impairment leading to end-organ damage Renal event Cardiovascular event Odds ratio (age and sex adjusted) Odds ratio (age and sex adjusted) * 6 6 * 4 4 * * * * 2 2 * 0 0 <15 15-30 30-150 150-300 >300 <15 15-30 30-150 150-300 >300 UAE (mg/24hr) UAE (mg/24hr) N 4,132 796 574 51 57 N 6,013 1,279 1,023 121 134 n 143 42 49 9 13 n 252 121 150 20 25 *P < 0.05 versus patients with a urinary albumin excretion (UAE) 15 mg/day. N = Number of patients with follow-up data available. n = Number of patients with an event.Gansevoort RT, et al. J Am Soc Nephrol. 2009;20(3):465-8.
LIFE sub-study: Kaplan-Meier plots on accumulated freedom of CV events according to UACR and LV mass UACR ≥1.406, LV mass ≥ 264 UACR ≥1.406, LV mass <194 UACR <1.406, LV mass <194 1.00 0.95 Freedom of CV events 0.90 0.85 0.80 0 12 24 36 48 60 Months CV = cardiovascular; UACR = urine albumin: creatinine ratio; LV = left ventricular; MI = myocardial infarction. CV events – CV death, non-fatal stroke or non- fatal MI – increase throughout the LV mass, both in patients with UACR above and below the median valueOlsen MH, et al. J Hum Hypertens. 2004;18:453-59.
Urinary albumin excretion is a strong predictor of all-cause mortality in the general population The PREVEND study High Normal MAU (UAC = 20 to <200 mg/L) Macroalbuminuria 6.0 5.5 CV death 5.0 4.5 4.0 Hazard ratio 3.5 Non-CV 3.0 death 2.5 2.0 1.5 1.0 0.5 0.0 1 10 100 1000 Urinary albumin concentration (mg/L) The relationship between urinary albumin concentration and CV mortality is already apparent at albuminuria levels considered to be normalHillege HL, et al. Circulation 2002;106:1777-82.
MAU and gross proteinuria associated with significantly higher risks of CV mortality in T2D The WESDR study Normoalbuminuria (n=460) (<30 mg/L urinary albumin) MAU (n=208) (30–300 mg/L urinary albumin) Gross proteinuria (n=172) (>300 mg/L urinary protein) 1.0 Proportion surviving 0.8 0.6 0.4 0.2 0 0 2 4 6 8 10 12 Years of follow up Log-Rank test p<0.001 Gross proteinuria (>300 mg/L) > Macroalbuminuia (>200 mg/L) The relative risk of CV mortality associated with MAU (30–300 mg urinary albumin) was 1.8Valmadrid CT, et al. Arch Intern Med. 2000;160:1093-100.
Risk associated with a given level of eGFR is independently increased in patients with higher levels of proteinuria The Alberta study End-stage renal disease Doubling of serum creatinine Normal Microalbuminuria Macroalbuminuria Rate per 1000 person years 100 60 Rate per 1000 person years 50 80 40 60 30 40 20 20 10 0 0 ≥60 45-59.9 30-44.9 15-29.9 ≥60 45-59.9 30-44.9 15-29.9 eGFR (mL/min/1.73 m2) eGFR (mL/min/1.73 m2) The risks of mortality, myocardial infarction, and progression to kidney failure associated with a given level of eGFR are independently increased in patients with higher levels of proteinuriaHemmelgarn BR, et al. JAMA. 2010;303(5):423-9.
Key clinical studies evaluating the predictive value of MAU on CV and renal riskChange of MAU as a predictorYear Study name Author/s Title Patient # Proteinuria, a target for renoprotection in patients De Zeeuw D,2004 RENAAL with type 2 diabetic nephropathy: lessons from N=1,513 et al. RENAAL. De Zeeuw D, Albuminuria, a therapeutic target for CV protection N=1,5132004 RENAAL et al. in type 2 diabetic patients with nephropathy. Reduction in albuminuria translates to reduction in Ibsen H, CV events in hypertensive patients: losartan2005 LIFE N=8,206 et al. intervention for endpoint reduction in hypertension study. Schmieder R, Changes in albuminuria predict mortality and2010 ONTARGET N=23,480 et al. morbidity in patients with vascular disease.
Antiproteinuric effect predicts nephroprotection in patients with type 2 diabetes The RENAAL study <0% (increase) 0%-30% >30% decrease 70 60 0-30% vs <0% p=0.0118 % with renal endpoint 50 >30% vs <0% p<0.0001 40 30 20 10 0 0 12 24 36 48 Months of follow-up The larger the treatment reduction of proteinuria, the lower the risk for renal endpointsDe Zeeuw D, et al. Kid Int. 2004;65:2309-20.
Reduction of proteinuria predicts cardiovascular prognosis in people with type 2 diabetes The RENAAL study Cardiovascular event Congestive heart failure >0 <30% <0% >30% >0 <30% <0% >30% 60 60 Patients (%) 40 40 Patients (%) 20 20 0 0 0 12 24 36 48 0 12 24 36 48 Months Months Kaplan-Meier Curves of CV events and congestive heart failure stratified according to the change of proteinuria after 6 months: <0% (n=631), >0 and <30% (n=393) and >30% (n=489). The larger the treatment reduction of proteinuria, the lower the risk for CV endpointsde Zeeuw D, et al. Circulation. 2004;11:921-7.
Increasing albuminuria is associated with an increased risk of CV events The LIFE study Composite CV endpoint rates stratified baseline albuminuria measurement (UACR)*3 X 8.84 to US measures, mg/g 24 >3 mg/mmol (n=2435, 1708, 1760) 22 1-3 mg/mmol (n=2219, 1827, 1946) 20 0.5-1 mg/mmol (n=1591, 1587, 1814) ≤ 0.5 mg/mmol (n=1961, 3385, 2458) Endpoint rate (%) 18 16 14 12 10 8 6 4 2 0 0 6 12 18 24 30 36 42 48 54 60 66 Month *Composite endpoint = first occurrence of cardiovascular death, nonfatal stroke, and nonfatal myocardial infarction; UACR = urinary albumin/creatinine ratio; The numbers in parentheses are the numbers of at-risk patients in each range of UACR at baseline, Years 2 and4. Reducing UACR is associated with a reduction in CV events in patients with hypertensionIbsen H, et al. Hypertension. 2005;45:198-202.
Controlling progression of MAU as a means of reducing CV risk The LIFE study Prognosis after reduction of albuminuria Composite endpoint of CV death, stroke and myocardial infarction 0.20 N= 9,193 hypertensive patients with LVH High Alb at BL/High at Yr 1 13.5% Proportion reaching composite endpoint 0.15 High Alb at BL/Low at Yr 1 9.4% 0.10 Low Alb at BL/High at Yr 1 8.6% 0.05 Low Alb at BL/Low at Yr 1 5.5% 0.00 0 20 40 60 Time (Months) CV = cardiovascular; LVH = left ventricular hypertrophy; Ab at BL = albuminuria at baseline/value after 1 year (Yr 1) Reducing UACR during treatment is associated with a reduction in CV death, stroke and myocardial infarction in patients with hypertensionIbsen H, et al. Hypertension 2005;45:198-202.
Change in MAU as a predictor of CV and renal outcomes in patients with vascular disease The ONTARGET/TRANSCEND study programme A) CV death decrease >50% vs minor change 0.140 minor change increase >100% vs minor change <0.0001 B) Composite CV endpoint decrease >50% vs minor change 0.032 minor change increase >100% vs minor change <0.0001 C) Combined renal endpoint decrease >50% vs minor change 0.019 minor change increase >100% vs minor change 0.005 0 1 2 Adjusted HR* (95 CI%) of changes in UACR from baseline to 2 year visit Analyses were adjusted for age, gender, BMI, smoking, alcohol consumption, eGFR, plasma glucose, BP and HR at baseline, BP change within 2 years and for baseline albuminuria. The risk of CV and renal outcomes is increased significantly if MAU is increased and is decreased if MAU is reducedSchmieder RE, et al. JASN 2011; In press.
Change in MAU as a predictor of all-cause mortality in patients with vascular disease The ONTARGET/TRANSCEND study programme All-cause mortality Decrease >50% vs minor change 0.026 Minor change Increase >100% vs minor change <0.0001 0 1 2 Adjusted HR* (95 CI%) of changes in UACR from baseline to 2 year visit Analyses were adjusted for age, gender, BMI, smoking, alcohol consumption, eGFR, plasma glucose, BP and HR at baseline, BP change within 2 years and for baseline albuminuria. The risk of all-cause mortality is increased significantly if MAU is increased and is decreased if MAU is reducedSchmieder RE, et al. JASN 2011; In press.
Understanding the clinical implications of MAUSummary• The RAAS plays a major role in development of albuminuria in accordance with the Steno hypothesis (Albuminuria reflects widespread vascular damage ). MAU is a strong and independent risk factor for cardio-renal disease UACR and eGFR are multiplicatively and independently associated with mortality risk without evidence of interaction Albumin is a continuous predictor of mortality starting at low levels, whereas eGFR is predictive only above a certain threshold Reducing proteinuria/MAU leads to a decreased risk in CV and renal outcomes and all-cause mortality.
Combining antihypertensive therapy prevents MAU in people with T2D and HT and normoalbuminuria The BENEDICT Study Proportion (%) of participants with MAU during treatment with trandolapril or placebo Placebo Trandolapril 15 microalbuminuria (%) Subjects with 10 5 0 0 6 12 18 24 30 36 42 48 Follow-up (Months) MAU = microalbuminuria; T2D = type 2 diabetes; HT = hypertension; BP = blood pressure; RAAS = renin-angiotensin-aldosterone system *Defined as UACR ≥20g/min in at least 2 of 3 consecutive overnight urine collections and confirmed after approx. 2 months in at least 3 consecutive overnight urine collections; †Significant difference (p=0.01) vs. placebo after adjusting for pre-specified covariates. Treatment with an ACE inhibitor reduces the incidence of MAU in individuals with T2D and hypertension verapamilRuggenenti P, et al. N Engl J Med. 2004;351(19):1941-51.
ARB therapy delays/prevents first occurrence of MAU The ROADMAP Study Placebo Olmesartan n=4,447 Cumulative proportion of patients 0.22 0.20 Hazard Ratio Risk reduction P value with microalbuminuria 0.18 0.16 0.770 -23% 0.0104 0.14 0.12 0.10 0.08 0.06 0.04 0.02 0.00 0 3 6 12 18 24 30 36 42 48 Time (months) Subjects: type 2 diabetes (T2D) and ≥1 additional CV risk factor (e.g. dyslipidaemia, hypertension, obesity, smoking). 94% of participants had blood pressure below 130/80 mmHg or were receiving antihypertensive treatment with a non-RAAS medication ARB therapy significantly delays the onset of MAU – by 23% compared with placebo in individuals with T2D (After correction for diastolic and systolic blood pressure, the risk reduction with olmesartan dropped to 18% and 17%, respectively, losing statistical significance )Haller H et al. Olmesartan for the Delay or Prevention of Microalbuminuria in Type 2 Diabetes. New Engl J Med 2011; 364:907-17.
Time to first occurrence of MAU ROADMAP: Correction for BP differencesBP-independent olmesartan effect: Analysis HR RR P-value DBP AUC DBP last mean Treatment 0.770 -23% p=0.0104 SBP AUC SBP last mean Treatment DBP 0 corrected* 0.823 -18% p=0.0596 (AUC) -5Risk reduction (%) SBP corrected* (AUC) 0.834 -17% p=0.0789 -10 DBP -15 corrected 0.810 -19% p=0.0398 (Last mean) -20 -17% -18% -19% -19% SBP corrected (Last mean) 0.814 -19% p=0.0451 -25 -23% * AUC = Area under the curve (SBP/DBP) from baseline to last assessment in DB period. Last mean SBP/DBP before MAU event.Haller H et al. Olmesartan for the Delay or Prevention of Microalbuminuria in Type 2 Diabetes. New Engl J Med 2011; 364:907-17.
Prevention of MAU: Realistic achievements in dailyclinical practiceSummary Current guidelines advocate early and aggressive individual management of risk factors in order to prevent progression to MAU Lifestyle modifications are important in the early intervention of CV risk MAU acts as a target for RAAS inhibition and prevention of cardio-renal damage Large clinical studies provide evidence that intervening in the development of MAU in high-risk patients prevents or delays renal and CV complications RAAS inhibitors (ARBs and ACE inhibitors) prevent/delay the development of MAU in patients with hypertension and/or diabetes
Key clinical studies evaluating prevention and treatmentof different levels of albuminuria and kidney disease Normal Microalbuminuria Proteinuria Proteinuria ESRD Stage 1 Stage 2 Stage 3 Stage 4 Stage 5 Mild Moderate Severe Dialysis IRMA 2 IDNTBENEDICT MARVAL RENAAL
Nephroprotective effects of olmesartan in hypertension: Reducing inflammatory markers Decreased serum hsCRP Decreased serum TNF-a Change of serum hsTNF-alpha (%) 15 15 Change of serum hsCRP (%) 10 Week 6 Week 12 10 Week 6 Week 12 Olmesartan Placebo Olmesartan Placebo Olmesartan Placebo Olmesartan Placebo 5 5 0 0 -5 -5 -10 -10 * -15 -15 #§ -20 * -20 -25 ** -25 Weeks 0−6: olmesartan (20 mg/day) or placebo Weeks 7−12: pravastatin 20 mg added to both treatment regimens *p<0.05, **p<0.02, #p<0.01 vs baseline; $p<0.05 olmesartan vs placebo hsCRP = high sensitivity C-reactive protein; TNF-α = tumor necrosis factor- α ARB treatment significantly reduces vascular microinflammation in patients with hypertension by as early as Week 6 of therapyFliser D, et al. Circulation. 2004;110:1103-7.
Achieving treatment goals in MAU-positive people: ESH-ESC guideline recommendations ESH-ESC guidelines: recommended intervention (patients with subclinical organ damage) Microalbuminuria ACEI , ARB, Renal dysfunction ACEI , ARB Left ventricular hypertrophy ACEI, CA, ARB Asymptomatic atherosclerosis CA, ACEI ACEI = Angiotensin converting enzyme inhibitor; ARB = Angiotensin II receptor blocker; CA = Calcium antagonist. RAAS inhibition by ACEIs or ARBs provides nephroprotection beyond blood pressure controlMancia G, et al. J Hypertens. 2007;25(6):1105-87.
Interventions in MAU-positive individuals:Evidence-based data, guidelines and practicalconsiderations for treatmentSummary Recent data have confirmed a link between MAU and CV disease in people with and without diabetes – even at low levels once considered to be ‘normal’ Treatment goals in MAU-positive individuals should be to: − Prevent/delay progression of CV and renal disease − Reduce progression and increase regression of MAU − Provide better control of renal and CV risk progression Therapies that inhibit RAAS (ACEIs and ARBs) have shown to help achieve these treatment goals ESH-ESC guidelines recommend that patients with hypertension and MAU should receive ACEIs and/or ARBs as the first-line treatment.
FDA reviews olmesartan safety record, cites CV deaths in trialsJune 14, 2010 | Steve StilesWashington, DC – The FDA is conducting a safety review of the angiotensin receptor blocker (ARB) olmesartan(Benicar, Daiichi Sankyo) after determining that diabetic patients taking the drug in two completed phase 3 trials may have had an excess risk of cardiovascular death, the regulatory body has announced . The safety announcement says that the FDAs review is "ongoing, and the agency has not concluded that Benicar increases the risk of death. FDA currently believes that the benefits of Benicar in patients with high blood pressure continue to outweigh its potential risks." The agency also notes that "other controlled clinical trials evaluating Benicar and other ARBs have not suggested an increased risk of cardiovascular-related death." The primary end points of the two trials were dominated by measures of renal function. In the Randomized Olmesartan and Diabetes Microalbuminuria Prevention (ROADMAP) study, conducted in Europe, 4447 patients with diabetes and at least one additional cardiovascular risk factor, but no evidence of renal dysfunction, were randomized to receive either olmesartan at 40 mg/day (n=2232) or placebo (n=2215). The trial, sponsored by Sankyo Pharma, ended in July 2009 .
There were 15 cardiovascular deaths—including seven cases of sudden death, five fatal MIs, twofatal strokes, and one death related to coronary revascularization—in the olmesartan groupcompared with a total of three CV deaths—one sudden death and two fatal strokes—in thecontrol group.In the Olmesartan Reducing Incidence of End Stage Renal Disease in Diabetic Nephropathy Trial(ORIENT), conduced in Japan and Hong Kong, 566 patients with diabetes and renal dysfunctionwere randomized to receive olmesartan at 10 mg/day to 40 mg/day (n=282) or placebo (n=284).Of the 10 cardiovascular deaths in the olmesartan group, five were sudden death, one was a fatalMI, three were fatal strokes, and one was of unknown CV cause. Three patients in the controlgroup died, two from sudden death and one from MI. ORIENT, sponsored by Daiichi Sankyo, wascompleted in February 2009 ."In considering the results of these trials, it is important to remember that numerous clinicaltrials with olmesartan as well as trials with other ARBs have not suggested an increased risk ofcardiovascular-related death," the FDA announcement notes. Still, the "FDA plans to review theprimary data from the two trials and the total clinical-trial data on olmesartan. Also, the agencywill evaluate additional ways to understand the findings from ROADMAP and ORIENT, in light ofinformation supporting the use of ARBs and angiotensin-converting enzyme (ACE) inhibitors incertain patients at high risk for cardiovascular events."