Cardiovascular risk in patients with early renal insufficiency: implications for the use of ACE inhibitors

Fixed-Dose Combination Therapy for the Prevention of Cardiovascular Diseases in CKD: An Individual Participant Data Meta-Analysis

BACKGROUND

Fixed-dose combination treatments reduce cardiovascular disease in primary prevention. We aim to explore whether those benefits differ in the presence of CKD.

METHODS

We conducted an individual participant data meta-analysis in 18,162 participants on the efficacy and safety of treatment for the primary prevention of cardiovascular disease. Combination therapies consisted of at least two BP-lowering drugs and a statin, with or without aspirin versus placebo or minimal care. Here, we examine the differential effect of fixed-dose combination treatment on the risk of developing cardiovascular disease in participants with a low eGFR (<60 ml/min per 1.73 m 2 ; Chronic Kidney Disease Epidemiology Collaboration formula) compared with a normal eGFR (≥60 ml/min per 1.73 m 2 ). The primary composite outcome was time to first occurrence of a combination of cardiovascular death, myocardial infarction, stroke, or arterial revascularization.

RESULTS

At baseline, the mean level of eGFR was 76 ml/min per 1.73 m 2 (SD 17). In total, 3315 (18%) participants had low eGFR at baseline. During a median follow-up of 5 years, among participants with normal eGFR, the primary outcome occurred in 232 (3%) participants in the treatment group compared with 339 (5%) in the control group (hazard ratio, 0.68; 95% confidence interval, 0.57 to 0.81; P < 0.001). In participants with low eGFR, the primary outcome occurred in 64 (4%) participants in the treatment group compared with 130 (8%) in the control group (hazard ratio, 0.49; 95% confidence interval, 0.36 to 0.66; P < 0.001; P for interaction 0.047). The relative risk reduction among participants with low eGFR was larger for combination strategies, including aspirin compared with treatments without aspirin. Apart from dizziness, other side effects did not differ between treatment and control groups, regardless of the stage of their kidney function.

CONCLUSIONS

A fixed-dose combination treatment strategy is effective and safe at preventing cardiovascular disease, irrespective of eGFR, but relative and absolute risk reductions are larger in individuals with low eGFR.

PODCAST

This article contains a podcast at https://dts.podtrac.com/redirect.mp3/www.asn-online.org/media/podcast/CJASN/2023_11_08_CJN0000000000000251.mp3.

Prediction of cardiovascular outcome by estimated glomerular filtration rate among high-risk patients: a Thai nationwide cohort study

BACKGROUND

Decline of estimated glomerular filtration rate (eGFR) is associated with increased cardiovascular (CV) morbidity and mortality, but the predictive value of different eGFR on CV outcomes is limited in Southeast Asian populations.

AIMS

We aimed to stratify CV outcomes according to renal function among Thai patients with high atherosclerosis risk.

METHODS

We performed a secondary analysis in a 5-year national cohort entitled "CORE-Thailand study." Subjects were classified in 6 groups according to baseline kidney function: group I, eGFR ≥ 90; group II, eGFR 60-89; group IIIa, eGFR 45-59; group IIIb, eGFR 30-44; group IV, eGFR 15-29; group V, eGFR < 15 ml/min/1.73 m² or receiving renal replacement therapy. The primary outcome was 4-point major adverse cardiovascular events (MACE). Secondary outcomes included all-cause mortality, CV mortality, hospitalization for heart failure, nonfatal myocardial infarction, and nonfatal stroke.

RESULTS

A total of 6376 subjects (3467 men and 2909 women) were categorized in 6 groups. After adjusting covariates in the Cox proportional hazards model, compared to group I, subjects in groups II-V had a 1.65-fold, 2.17-fold, 2.67-fold, 4.24-fold, and 4.87-fold risk for 4-point MACE, respectively, with statistical significance at P < 0.05 in all groups. Kaplan-Meier analysis illustrated stepwise lower survivals from 4-point MACE following the groups with lower baseline eGFR (log-rank test with P < 0.001). All secondary outcomes showed similar trends as the primary outcome, except nonfatal stroke.

CONCLUSION

Lower baseline kidney function was independently associated with increased risk of CV events and all-cause mortality in Thai populations at high CV risk.

Anesthesia for Patients with Concomitant Cardiac and Renal Dysfunction

Renal disease and cardiovascular disease are commonly encountered in the same patient. The dynamic interactions between renal disease and cardiovascular disease have an impact on perioperative management. Renal failure is an independent risk factor for cardiovascular disease and the link between the two disease states remains to be fully elucidated.

Neutrophil gelatinase-associated lipocalin levels are U-shaped in the Ludwigshafen Risk and Cardiovascular Health (LURIC) study-Impact for mortality

INTRODUCTION

Neutrophil gelatinase-associated lipocalin (NGAL) is a glycoprotein released by damaged renal tubular cells and mature neutrophils. It is elevated in kidney injury, but also in patients with coronary artery disease (CAD) and myocardial infarction. We investigated the prognostic value of NGAL for total and cardiovascular mortality in patients undergoing coronary angiography without history of renal insufficiency at inclusion into the study.

PARTICIPANTS

The LURIC study is an ongoing prospective cohort study of patients referred for coronary angiography and is designed to evaluate determinants of cardiovascular health.

RESULTS

NGAL was determined in plasma of 2997 persons (mean age: 62.7 years; 69.7% men) with a follow up for 10 years. 2358 patients suffered from CAD and 638 did not-these patients served as controls. Stable CAD was found in 1408 and unstable CAD in 950 patients. Death rate from cardiovascular events and all causes was highest in patients within the 4th quartile of NGAL (≥56 ng/ml, p<0.001 vs third quartile), even after adjustment for age and gender. According to multivariable-adjusted Cox analysis adjusting for well-known cardiovascular risk factors, as well as lipid lowering therapy, angiographic CAD, and C-reactive protein we found patients in the highest NGAL quartile being at increased risk for cardiovascular (hazard ratio (HR) 1.33, 95%CI 1.05-1.67, p = 0.016) and all cause mortality (HR 1.29 95%CI 1.07-1.55, p = 0.007) compared to those in the third quartile. The lowest risk was seen in the third quartile of NGAL (41-56 ng/ml) suggesting a U-shaped relationship between NGAL and mortality. Further adjustment for creatinine abrogated the predictive effect of NGAL. However, the 3rd and 4th quartiles of NGAL were significantly associated with higher neutrophil counts, which were associated with CAD, non-ST elevation and ST-elevation myocardial infarction (p<0.05).

CONCLUSIONS

Plasma NGAL concentrations are mainly derived from neutrophils and do not predict mortality independent of renal function.

MicroRNAs mediate the cardioprotective effect of angiotensin-converting enzyme inhibition in acute kidney injury

Cardiovascular disease, including cardiac hypertrophy, is common in patients with kidney disease and can be partially attenuated using blockers of the renin-angiotensin system (RAS). It is unknown whether cardiac microRNAs contribute to the pathogenesis of cardiac hypertrophy or to the protective effect of RAS blockade in kidney disease. Using a subtotal nephrectomy rat model of kidney injury, we investigated changes in cardiac microRNAs that are known to have direct target genes involved in the regulation of apoptosis, fibrosis, and hypertrophy. The effect of treatment with the angiotensin-converting enzyme (ACE) inhibitor ramipril on cardiac microRNAs was also investigated. Kidney injury led to a significant increase in cardiac microRNA-212 and microRNA-132 expression. Ramipril reduced cardiac hypertrophy, attenuated the increase in microRNA-212 and microRNA-132, and significantly increased microRNA-133 and microRNA-1 expression. There was altered expression of caspase-9, B cell lymphoma-2, transforming growth factor-β, fibronectin 1, collagen type 1A1, and forkhead box protein O3, which are all known to be involved in the regulation of apoptosis, fibrosis, and hypertrophy in cardiac cells while being targets for the above microRNAs. ACE inhibitor treatment increased expression of microRNA-133 and microRNA-1. The inhibitory action of ACE inhibitor treatment on increased cardiac NADPH oxidase isoform 1 expression after subtotal nephrectomy surgery suggests that inhibition of oxidative stress is also one of mechanism of ACE inhibitor-mediated cardioprotection. These finding suggests the involvement of microRNAs in the cardioprotective action of ACE inhibition in acute renal injury, which is mediated through an inhibitory action on profibrotic and proapoptotic target genes and stimulatory action on antihypertrophic and antiapoptotic target genes.

The effect of spironolactone upon corticosteroid hormone metabolism in patients with early stage chronic kidney disease

CONTEXT

Aldosterone has emerged as an important mediator of disease progression and mortality in patients with chronic heart and kidney disease (CKD). Despite the increasing use of mineralocorticoid receptor antagonists in these patients, little is known about the effects on corticosteroid hormone secretion and metabolism.

OBJECTIVE

To assess corticosteroid hormone secretion and metabolism in patients with early stage CKD before and after spironolactone (Spiro).

DESIGN

Randomized, double-blind, placebo-controlled interventional study.

SETTING

Single tertiary referral centre.

PATIENTS

A total of 112 patients with stable stage 2/3 CKD.

INTERVENTIONS

Patients were randomized to receive either Spiro 25 mg once daily or placebo for 36 weeks.

MAIN OUTCOME MEASURES

Plasma renin activity (PRA), angiotensin II (AngII) and steroid hormones were analysed by standard assays; urinary corticosteroid hormone metabolites (5α+5β-tetrahydro-cortisol (5α+5β-THF), TH-cortisone (THE), 3α5β-TH-aldosterone (TH-Aldo), 5α+5β-TH-deoxycorticosterone (5α+5β-TH-DOC), TH-11-desoxycortisol (THS)) were analysed by gas chromatography/mass spectrometry.

RESULTS

Plasma aldosterone concentration (PAC) was inversely correlated with eGFR (r = -0·331, P < 0·001). Urinary 24-h excretion of TH-Aldo was correlated with PAC (r = 0·214, P < 0·05) and diastolic blood pressure (BP) (r = 0·212, P = <0·05), whereas total 24-h urinary cortisol metabolite excretion was correlated with systolic BP (r = 0·316, P < 0·01). In addition, 11β-hydroxysteroid dehydrogenase (11β-HSD) type 1 activity (urinary 5α+5β-THF)/THE) ratio) was correlated with PRA (r = 0·277, P < 0·01). Spiro treatment significantly reduced BP (123 ± 11/76 ± 7 vs 119 ± 11/73 ± 8 mmHg, P < 0·01) despite renin-angiotensin-aldosterone system induction, reflected by increased urinary 24-h TH-Aldo excretion (17·6 (12, 86) vs 26 (18, 80) μg/24 h, P < 0·05). By contrast, Spiro had no effect on total urinary cortisol metabolite excretion, 11β-hydroxylase, 11β-HSD type 1 and 2 activity.

CONCLUSIONS

Aldo and cortisol are positively associated with BP suggesting that adrenal hyperactivity may in part explain the increased cardiovascular risk in patients with early end-stage CKD. Addition of Spiro had no effect on glucocorticoid metabolism or total 24-h corticosteroid production.

Glomerulonephritis and managing the risks of chronic renal disease

The rising global burden of chronic renal disease, the high cost of providing renal replacement therapies, and renal disease also being a risk factor for cardiovascular disease is increasing focus on renal disease prevention. This article focuses on the aspects of renal disease (specifically poststreptococcal glomerulonephritis [PSGN] and chronic kidney disease [CKD]) in Indigenous populations in Australia, New Zealand, Canada, and the United States that diverge from those typically seen in the general population of those countries. The spectrum of renal and many other diseases seen in Indigenous people in developed countries is similar to that seen in developing countries. Diseases like PSGN that have largely disappeared in developed countries still occur frequently in Indigenous people. CKD during the childhood years is due to congenital anomalies of the kidney and urinary tract in up to 70% of cases and occurs later in polycystic kidney disease and childhood-onset diabetes. Several risk factors for CKD in adulthood are already present in childhood.

Facilitation of central imidazoline I(1)-site/extracellular signal-regulated kinase/p38 mitogen-activated protein kinase signalling mediates the hypotensive effect of ethanol in rats with acute renal failure

BACKGROUND AND PURPOSE

This study investigated the role of central sympathetic activity and related mitogen-activated protein kinase (MAPK) signalling in the cardiovascular effects of ethanol in a model of acute renal failure (ARF).

EXPERIMENTAL APPROACH

The effects of pharmacological interventions that inhibit peripheral or central sympathetic activity or MAPK on the cardiovascular actions of ethanol in rats with ARF induced by glycerol were evaluated.

KEY RESULTS

Glycerol (50%, 10 mL.kg(-1), i.m.) caused progressive increases and decreases in blood pressure (BP) and heart rate (HR) respectively. Subsequent i.v. ethanol (0.25 or 1 g.kg(-1)) elicited dose-related changes in BP (decreases) and HR (increases). These effects were replicated after intracisternal (i.c.) administration of ethanol. Blockade of nicotinic cholinoceptors (nAChR, hexamethonium, 20 mg.kg(-1)) or alpha(1)-adrenoceptors (prazosin, 1 mg.kg(-1)) attenuated cardiovascular effects of ethanol. Ethanol hypotension was also attenuated after the centrally acting sympatholytic drug moxonidine (selective I(1)-site agonist, 100 microg.kg(-1) i.v.), but not guanabenz (selective alpha(2)-receptor agonist, 30 microg.kg(-1), i.v.), suggesting involvement of central circuits of I(1) sites in ethanol-evoked hypotension. Selective blockade I(1) sites (efaroxan) but not alpha(2) (yohimbine) adrenoceptors abolished the hypotensive response to ethanol. Intracisternal administration of PD98059 or SB203580, inhibitors of extracellular signal-regulated kinase (ERK 1/2) and p38 MAPK, respectively, reduced the hypotensive action of moxonidine or ethanol. When used simultaneously, the two MAPK inhibitors produced additive attenuation of ethanol hypotension.

CONCLUSIONS AND IMPLICATIONS

Sympathoinhibitory pathways of central I(1)-sites and downstream ERK/p38 MAPK signalling were involved in the hypotensive action of ethanol in ARF.

Situational and dispositional predictors of nurse manager burnout: a time-lagged analysis

BACKGROUND

Burnout among nurses is a serious condition that threatens their own health and that of their patients. In current health care settings, nurses are particularly at risk for burnout given the increased patient acuity and the worsening nursing shortage.

AIM

This study examined the influence of effort-reward imbalance, a situational variable, and core self-evaluation, a dispositional variable, on nurse managers' burnout levels over a 1-year period.

METHODS

A predictive longitudinal survey design was used to examine the relationships described in the model. One hundred and thirty-four nurse managers responded to a mail survey at two points in time.

RESULTS

As hypothesized, both personal and situational factors influenced nurse manager burnout over a 1-year time frame. Although burnout levels at Time 1 accounted for significant variance in emotional exhaustion levels 1 year later (beta = 0.355), nurses' effort-reward imbalance (beta = 0.371) and core self-evaluations (beta = -0.166) explained significant additional amounts of variance in burnout 1 year later.

CONCLUSION

Both personal and situational factors contribute to nurse manager burnout over time. Implications for nursing management Managers must consider personal and contextual factors when creating work environments that prevent burnout and foster positive health among nurses at work.

Inverse association between serum concentrations of neopterin and antioxidants in patients with and without angiographic coronary artery disease

Neopterin is released from human monocyte-derived macrophages upon stimulation with interferon-gamma and is a sensitive indicator for cellular immune activation. Furthermore, reactive oxygen species (ROS) are produced in case of immune activation and inflammation. In a cross-sectional approach, plasma concentrations of neopterin and of antioxidant compounds and vitamins were compared in 1463 patients investigated by coronary angiography, which were recruited within the LUdwigshafen RIsk and Cardiovascular Health (LURIC) study. Serum neopterin concentrations were higher in patients with coronary artery disease (CAD; mean+/-S.D.: 8.7+/-7.3 nmol/L) compared to controls (7.4+/-5.0 nmol/L; Welch's t-test: p<0.001). Mean concentrations of ascorbic acid (p<0.0001), gamma-tocopherol (p<0.05), lycopene (p<0.001), lutein+zeaxanthin (p<0.05), alpha-carotene (p<0.05) and beta-carotene (p<0.05) were lower in CAD than in controls. Neopterin concentrations correlated with CAD-score (r(s)=0.156; p<0.0001) and inversely with antioxidants lycopene (r(s)=-0.277; p<0.0001) and lutein+zeaxanthin (r(s)=-0.175; p<0.0001) levels and with vitamins ascorbic acid (r(s)=-0.207; p<0.0001) and alpha-tocopherol (r(s)=-0.105; p<0.0001). The study demonstrates that higher neopterin production is associated with lower concentrations of antioxidant compounds in patients at risk for atherosclerosis. Results suggest that lower concentrations of antioxidant compounds may relate to higher grade of chronic immune activation in patients.

The role of angiotensin II type 1 receptor blockers in the prevention and management of diabetes mellitus

Angiotensin II Receptor blockers (ARBs) are an important addition to the current range of medications available for treating a wide spectrum of diseases including cardiovascular diseases. Coronary heart disease (CHD) is the most common cause of death in the United Kingdom and worldwide. More importantly, the presence of the metabolic syndrome and the likelihood of diabetes mellitus taking on epidemic proportions in the years to come all threaten to maintain the mortality rate due to CHD. This review article focuses on the clinical studies that have helped define the trends in the usage of these agents in the prevention and treatment of diabetes mellitus and its complications and also explores possible mechanisms of action and future developments.

Assessment of glomerular filtration rate in addition to albuminuria is important in managing type II diabetes

Although much emphasis has been placed on screening for albuminuria in type II diabetic patients, less attention has been focused on the role of glomerular filtration rate (GFR) in the assessment of risk. Herein, we examined the association between GFR and vascular complications in a consecutive cohort of 5174 type II diabetic patients between 1995 and 2000. Renal function was assessed by GFR (estimated by Modification of Diet in Renal Disease equation). The frequency of chronic kidney disease (CKD) as defined by GFR <60 ml/min/1.73 m(2), micro- and macrovascular complications, and their associations were analyzed. In this study cohort, 6% had serum creatinine > or =150 micromol/l and 15.8% had CKD. After adjustment for potential confounders, including urinary albumin excretion, odds ratios [95% confidence interval (CI)] across different stages of estimated GFR (> or =90, 60-89, 30-59, 15-29, <15 ml/min/1.73 m(2)) for macrovascular disease were 1.00, 1.42 [1.12-1.80], 1.80 [1.32-2.45], 2.74 [1.64-4.56], and 4.05 [1.77-9.26], respectively (P for trend <0.001); for retinopathy were 1.00, 1.23 [1.04-1.46], 1.80 [1.40-2.30], 2.05 [1.25-3.37], and 4.12 [1.56-10.90], respectively (P for trend <0.001); for sensory neuropathy were 1.00, 1.53[1.27-1.85], 2.09 [1.58-2.76], 4.32 [2.41-7.77], and 3.16 [1.25-8.02], respectively (P for trend <0.001); and for microalbumuria (with GFR <15 ml/min/1.73 m(2) excluded from the analysis) were 1.00, 1.51 [1.30-1.75], 5.80 [4.52-7.44], and 52.5 [16.4-168.2] respectively (P for trend <0.001). Measurement of serum creatinine alone without GFR may underestimate renal impairment in type II diabetic patients. Decreasing GFR was significantly associated with increasing frequency of micro- and macrovascular complications.

Cardiovascular risk in patients with mild renal insufficiency: implications for the use of ACE inhibitors

We review the evidence linking mild renal insufficiency (MRI) with increased cardiovascular risk. MRI is associated with a number of cardiovascular risk factors, including nighttime hypertension, and increased levels of lipoprotein (a), homocysteine, asymmetric dimethyl-arginine, and inflammation and insulin resistance markers and mediators. Epidemiologic evidence associates coronary artery disease and nephrosclerosis, a frequent cause of early renal insufficiency in the elderly. In a middle-aged general population MRI was found in 8% of women and 9% of men, but was not associated with cardiovascular disease. Nonetheless, in a representative sample of middle-aged British men the risk of stroke was 60% higher for the sub-group with MRI: in people at high cardiovascular risk (mostly coronary disease), the HOPE study found a 2-fold (unadjusted) or 1.4-fold (adjusted) higher incidence of cardiovascular outcomes with MRI. The combined incidence of cardiovascular death, myocardial infarction and stroke increased with the level of serum creatinine. Several studies have examined the cardiovascular risk associated with MRI in hypertension. In HDFP, as in HOPE, cardiovascular mortality increased with serum creatinine (five-fold difference in cardiovascular mortality between the lowest and the highest creatinine strata). The risk associated with renal insufficiency was independent of other classic cardiovascular risk factors. Two trials of hypertensives with low risk (HOT and a small Italian trial) found that cardiovascular outcomes approximately doubled in subjects with MRI. Another study (MRFIT) found that it was not baseline creatinine, but its increase on follow-up that predicted future cardiovascular disease. These observational data suggest that regardless of etiology MRI is a strong predictor of cardiovascular disease and is found in 10% of populations at low cardiovascular risk and in up to 30% of those at high risk. No prospective therapeutic trials aimed at reducing the cardiovascular burden in people with MRI are available. Subgroup analyses of the HOPE study indicate that angiotensin-converting enzyme (ACE) inhibition with ramipril is beneficial and does not increase the risk of such side effects as acute renal failure or hyperkalemia. Thus the frequent practice of withholding ACE inhibitors from patients with mild renal insufficiency is unwarranted, especially since MRI identifies a group at high risk that appears to benefit most from treatment. Moreover, there is evidence that ACE inhibitors improve renal outcomes in renal insufficiency. Prospective studies should test the predictive power of early renal insufficiency for cardiovascular disease and prognosis with various therapeutic options.

The HOPE (Heart Outcomes Prevention Evaluation) Study and its consequences

The HOPE study was a 19 country, prospective randomized trial in which the ACE-inhibitor Ramipril but not Vitamin E significantly reduced the risk of future cardiovascular events in a high-risk population of men and women, including many with diabetes. The benefits were present in all sub-groups, independent of the presence or absence of diabetes, hypertension, evidence of cardiovascular disease, microalbuminuria, blood pressure lowering, the use of aspirin, lipid-lowering or antihypertensive medication. It provided clear evidence that Ramipril should safely and cost-effectively be used in individuals not known to have low ventricular ejection fraction or heart failure but at high-risk of cardiovascular events. It was also beneficial in patients with renal insufficiency, reducing progression of proteinuria and development of new microalbuminuria. It provided micro- and macrovascular benefits in people with diabetes, reduced the development of new cases of diabetes and showed a positive and graded association between the waist-to-hip ratio and the risk of developing diabetes. Sub-studies completed and on-going into the predictive role of natriuretic peptides, infectious and inflammatory markers, provide insight into possible mechanisms of action of Ramipril.

Complications of chronic kidney disease: anemia, mineral metabolism, and cardiovascular disease

This article focuses on the importance of three major complications of chronic kidney disease: (1) anemia, (2) calcium-phosphorus regulation and bone disease, and (3) cardiovascular risk profiling and treatment. The arguments for early and effective intervention have been amply made with respect to these three complications. Substantive trial data are sorely need to provide the definitive evidence that effective treatment of these complications results in better outcomes.

Effects of vitamin E on cardiovascular outcomes in people with mild-to-moderate renal insufficiency: Results of the HOPE Study

BACKGROUND

A controlled trial reported cardiovascular benefits of vitamin E in terminal renal insufficiency. There are no data for renal insufficiency before the stage of terminal renal failure. We evaluated effects of vitamin E supplementation on cardiovascular and renal outcomes in 993 people with a serum creatinine > or =1.4 to 2.3 mg/dL.

METHODS

Post-hoc analysis of a randomized trial that compared treatment with natural source vitamin E (400 IU/day) to placebo in 9541 people, 993 of which had renal insufficiency. Participants had either known cardiovascular disease or diabetes and at least one additional coronary risk factor. Exclusion criteria included a serum creatinine > 2.3 mg/dL and dipstick-positive proteinuria. The primary study outcome after an average of 4.5 years was the composite of myocardial infarction, stroke, or cardiovascular death. Secondary outcomes included revascularizations, total mortality, and clinical proteinuria.

RESULTS

In renal insufficiency, vitamin E supplementation had a neutral effect on the primary study outcome, on each component of the composite primary outcome, and on all secondary outcomes. Two hundred twenty-four primary outcomes, 23% of the vitamin E group and 22.1% of the placebo group, relative risk 1.03 (95% CI, 0.79-1.34; P= 0.82), were observed, and 585 secondary outcomes, including death in 17% and 18.8% of the vitamin E and placebo groups, respectively (RR 0.88, 95% CI, 0.66-1.18; P= 0.40). There was no effect of vitamin E on progression of proteinuria.

CONCLUSION

In people with mild-to-moderate renal insufficiency at high cardiovascular risk, vitamin E at a dose of 400 IU/day had no apparent effect on cardiovascular outcomes.

Cardiovascular risk in patients with mild renal insufficiency

We reviewed the evidence linking mild renal insufficiency (MRI) to an increased cardiovascular risk. A number of cardiovascular risk factors become prevalent with MRI, including night-time hypertension, increase in lipoprotein(a), in homocysteine, in asymmetric dimethyl-arginine (ADMA), markers and mediators of inflammation, and insulin resistance. Also, an epidemiologic association between coronary artery disease and nephrosclerosis, a frequent cause of mild renal insufficiency in the elderly, is documented. In the middle-aged, general population MRI, found in 8% of women and 9% of men, was not associated with cardiovascular disease. However, in a representative sample of middle-aged British men, the risk of stroke was 60% higher for the subgroup of people with MRI; in people at high cardiovascular risk (mostly coronary disease), the HOPE study found a 2-fold (unadjusted), or 1.4-fold (adjusted), higher incidence of cardiovascular outcomes with MRI. The incidence of primary outcome increased with the level of serum creatinine. Several studies determined the cardiovascular risk associated with MRI in hypertension. In HDFP, as in HOPE, cardiovascular mortality increased with higher serum creatinine (five-fold difference in cardiovascular mortality between the lowest and the highest creatinine strata). The risk associated with renal insufficiency was independent from other classic cardiovascular risk factors. In hypertensives with low risk, the HOT, and a small Italian trial found about a doubling in cardiovascular outcomes in MRI. However, in MRFIT, increase in follow-up creatinine predicted future cardiovascular disease, not baseline creatinine. These observational data suggest that MRI, independent of etiology, is a strong predictor of cardiovascular disease, present in 10% of a population at low risk, and up to 30% at high cardiovascular risk. No prospective therapeutic trials, aimed at reducing the cardiovascular burden in people with MRI, are available. Subgroup analyses of the HOPE study indicate that ACE inhibition with ramipril is beneficial without an increased risk for side effects like acute renal failure or hyperkalemia. Thus, the frequent practice of withholding ACE inhibitors from patients with mild renal insufficiency is unwarranted, especially since this identifies a group at high risk that appears to benefit most from treatment. In addition, there is evidence that ACE inhibitors improve renal outcomes in renal insufficiency. Prospective studies should test the predictive power of MRI for cardiovascular disease and therapeutic options.