Microalbuminuria during acute myocardial infarction; a strong predictor for 1-year mortality

Soluble receptor for advanced glycation end-products positively correlated to kidney injury with coronary heart disease

AIMS

Coronary heart disease (CHD) patients with changed serum soluble receptor for advanced glycation end products (sRAGE) will experience microalbuminuria and even kidney dysfunction. However, the role of sRAGE for microalbuminuria in CHD is still not established. This study aimed to evaluate the association between sRAGE and early kidney dysfunction in CHD patients.

MATERIALS AND METHODS

In this cross-sectional study, sRAGE and urinary albumin-to-creatinine ratio (uACR) were measured in hospitalized CHD patients who have undergone coronary arteriography to evaluate the distinction and correlation between sRAGE and uACR.

RESULTS

There were 127 CHD patients (mean age: 63.06 ± 10.93 years, 93 males) in the study, whose sRAGE were 1.83 ± 0.64 μg/L. The sRAGE level was higher in kidney injury group (uACR ≥ 30 mg/g) compared with no kidney injury group (uACR < 30 mg/g) [(2.08 ± 0.70 vs. 1.75 ± 0.61) μg/L, P < 0.05]. Moreover, the positive correlation between serum sRAGE and uACR was significant in CHD patients (r = 0.196, P < 0.05). Binary logistic regression suggests sRAGE as a predictor for microalbuminuria in CHD patients [Odd Ratio = 2.62 (1.12-6.15), P < 0.05)]. The area under the receiver operating characteristic curve (AUC) of sRAGE is higher than that of the traditional indicators of renal function such as creatinine and estimated glomerular filtration rate, indicating sRAGE might have a good performance in evaluating early kidney injury in CHD patients [AUC is 0.660 (0.543-0.778), P < 0.01)].

CONCLUSIONS

Serum sRAGE was positively correlated to uACR and might serve as a potential marker to predict early kidney injury in CHD patients.

Microalbuminuria and mortality in individuals with coronary heart disease: A meta-analysis of a prospective study

AIM

Microalbuminuria has been elevated as an outcome predictor in cardiovascular medicine. However, due to the small number of studies investigating the association of microalbuminuria and mortality in the coronary heart disease (CHD) population, the prognosis value of microalbuminuria in CHD remains under debate. The objective of this meta-analysis was to investigate the relationship between microalbuminuria and mortality in individuals with CHD.

METHOD

A comprehensive literature search was performed using Pubmed, EuroPMC, Science Direct, and Google Scholar from 2000 to September 2022. Only prospective studies investigating microalbuminuria and mortality in CHD patients were selected. The pooled effect estimate was reported as risk ratio (RR).

RESULTS

5176 patients from eight prospective observational studies were included in this meta-analysis. Individuals with CHD have a greater overall risk of all-cause mortality (ACM) [rR = 2.07 (95% CI = 1.70-2.44); p = 0.0003; I2 = 0.0%] as well as cardiovascular mortality (CVM) [rR = 3.23 (95% CI = 2.06-4.39), p < 0.0001; I2 = 0.0%]. Subgroup analysis based on follow-up duration and a subset of CHD patients were similarly associated with an increased risk of ACM.

CONCLUSION

This meta-analysis indicates that microalbuminuria is associated with a higher risk of mortality in individuals with CHD. Microalbuminuria can serve as a predictor of poor outcomes in CHD patients.

Microalbuminuria during acute coronary syndrome: Association with 22-year mortality and causes of death. The ABC-8* study on heart disease. (*ABC is an acronym for Adria, Bassano, Conegliano, and Padova Hospitals)

BACKGROUND

Microalbuminuria is associated with adverse outcomes in acute coronary syndrome (ACS) patients.

METHODS

To evaluate the very long-term association between Microalbuminuria and the overall mortality and causes of death in this clinical setting, we prospectively studied 579 unselected ACS patients admitted to three hospitals. The baseline albumin-to-creatinine ratio (ACR) was measured on days 1, 3, and 7 in 24-h urine samples. Patients were followed for 22 years or until death.

RESULTS

Virtually all patients completed follow-up; 449(78%) had died: 41% due to non-sudden cardiac death (non-SCD), 19% sudden cardiac death (SCD), 40% due to non-cardiac (non-CD) death. Using unadjusted Cox regression analysis, ACR was a significant predictor of all-cause mortality (hazard ratio [HR] 1.26;95%confidence interval [CI] 1.22-1.31; p˂0.0001) and the three causes of death (HR 1.40;95%CI 1.32-1.48; p˂0.0001), (HR 1.22;95%CI 1.12-1.32; p˂0.0001) and (HR 1.16;95%CI 1.09-1.23; p˂0.0001) for non-SCD, SCD and non-CD respectively. Using a fully adjusted model, ACR was a significant independent predictor of all-cause mortality (HR 1.12; 95%CI 1.08-1.16; p˂0.0001) and only non-SCD (HR 1.21; 95%CI 1.14-1.29; p˂0.0001). There was a positive interaction between ACR level and history of AMI (HR 1.15; 95%CI 1.03-1.29; p = 0.01) and the presence of heart failure at admission (HR 1.11; 95%CI 1.01-1.24; p = 0.04), and negative interaction with higher than median LVEF (HR 0.89; 95%CI 0.80-0.99; p = 0.03) for all-cause mortality at the multivariable level.

CONCLUSION

Based on the present analysis, baseline urinary albumin excretion during ACS is a strong independent predictor of the very long-term mortality risk, chiefly due to non-sudden cardiac death.

Long-Term Variation in Kidney Function and Its Impact After Acute Myocardial Infarction

Kidney disease (KD) in patients with acute myocardial infarction (AMI) is associated with major cardiovascular events (MACE). We sought to compare the long-term variation in KD in patients with AMI versus controls and its value as a risk factor for MACE in patients with AMI. A cohort of 300 outpatients with AMI, recruited between 2014 and 2016 in Barcelona, Spain, were compared with a control cohort matched 1:1 based on age and several risk factors for developing KD. Annual estimated glomerular filtration rate (eGFR) using MDRD-4 formula and albuminuria were collected and patients were followed up for the occurrence of MACE (death, heart failure hospitalization, AMI, or stroke). After a median follow-up of 5.3 years, the decline in eGFR was more pronounced in patients with AMI (-1.15 ml/min/1.73 m²/ per year in patients with AMI vs -0.81 ml/min/1.73 m² per year in controls, p = 0.018 between the ß coefficients of both regression slopes). In patients with AMI, those with the greatest eGFR decline during follow-up had more MACE (hazard ratio [HR] for first vs fourth quartiles = 3.33, p <0.001). In multivariate analysis, after excluding patients with baseline KD, a newly diagnosed eGFR <60 ml/min/1.73 m² during follow-up was associated with MACE (HR = 3.21, p <0.001), as well as new onset albuminuria >30 mg/g (HR = 6.93, p <0.001) and the combination of both (HR 5.63, p <0.001). In conclusion, the decline in eGFR after AMI is more pronounced than in the general population. A longitudinal drop in eGFR and newly diagnosed albuminuria during follow-up are associated with MACE and can be useful tools to reclassify the risk profile after AMI.

Association between atherosclerotic cardiovascular diseases risk and renal outcome in patients with type 2 diabetes mellitus

AIMS

Chronic kidney disease (CKD) and diabetes mellitus increase atherosclerotic cardiovascular diseases (ASCVD) risk. However, the association between renal outcome of diabetic kidney disease (DKD) and ASCVD risk is unclear.

METHODS

This retrospective study enrolled 218 type 2 diabetic patients with biopsy-proven DKD, and without known cardiovascular diseases. Baseline characteristics were obtained and the 10-year ASCVD risk score was calculated using the Pooled Cohort Equation (PCE). Renal outcome was defined as progression to end-stage renal disease (ESRD). The association between ASCVD risk and renal function and outcome was analyzed with logistic regression and Cox analysis.

RESULTS

Among all patients, the median 10-year ASCVD risk score was 14.1%. The median of ASCVD risk score in CKD stage 1, 2, 3, and 4 was 10.9%, 12.3%, 16.5%, and 14.8%, respectively (p = 0.268). Compared with patients with lower ASCVD risk (＜14.1%), those with higher ASCVD risk had lower eGFR, higher systolic blood pressure, and more severe renal interstitial inflammation. High ASCVD risk (>14.1%) was an independent indicator of renal dysfunction in multivariable-adjusted logistic analysis (OR, 3.997; 95%CI, 1.385-11.530; p = 0.010), though failed to be an independent risk factor for ESRD in patients with DKD in univariate and multivariate Cox analysis.

CONCLUSIONS

DKD patients even in CKD stage 1 had comparable ASCVD risk score to patients in CKD stage 2, 3, and 4. Higher ASCVD risk indicated severe renal insufficiency, while no prognostic value of ASVCD risk for renal outcome was observed, which implied macroangiopathy and microangiopathy in patients with DKD were related, but relatively independent.

Chronic kidney disease measures for cardiovascular risk prediction

Chronic kidney disease (CKD) affects 15-20% of adults globally and causes various complications, one of the most important being cardiovascular disease (CVD). CKD has been associated with many CVD subtypes, especially severe ones like heart failure, independent of potential confounders such as diabetes and hypertension. There is no consensus in major clinical guidelines as to how to incorporate the two key measures of CKD (glomerular filtration rate and albuminuria) for CVD risk prediction. This is a critical missed opportunity to appropriately refine predicted risk and personalize prevention therapies according to CKD status, particularly since these measures are often already evaluated in clinical care. In this review, we provide an overview of CKD definition and staging, the subtypes of CVD most associated with CKD, major pathophysiological mechanisms, and the current state of CKD as a predictor of CVD in major clinical guidelines. We will introduce the novel concept of a "CKD Add-on", which allows the incorporation of CKD measures in existing risk prediction models, and the implications of taking into account CKD in the management of CVD risk.

Diagnostic and Prognostic Biomarkers for Myocardial Infarction

The incidence of myocardial infarction (MI) increases every year worldwide. Better diagnostic and prognostic biomarkers for clinical applications are the consistent pursuit of MI research. In addition to electrocardiogram, echocardiography, coronary angiography, etc., circulating biomarkers are essential for the diagnosis, prognosis, and treatment effect monitoring of MI patients. In this review, we assessed both strength and weakness of MI circulating biomarkers including: (1) originated from damaged myocardial tissues including current golden standard cardiac troponin, (2) released from non-myocardial tissues due to MI-induced systems reactions, and (3) preexisted in blood circulation before the occurrence of MI event. We also summarized newly reported MI biomarkers. We proposed that the biomarkers preexisting in blood circulation before MI incidents should be emphasized in research and development for MI prevention in near future.

Value of microalbuminuria in the diagnosis of heart failure with preserved ejection fraction

OBJECTIVE

Elevated microalbuminuria (MAU) levels have been demonstrated in patients with heart failure with reduced ejection fraction (HFrEF). However, nothing is known about MAU levels in patients with heart failure with preserved ejection fraction (HFpEF). Therefore, the aim of our study was to explore the relationship between MAU levels and HFpEF.

METHODS

The MAU and N‑terminal B‑type natriuretic peptide (NT-proBNP) concentrations were examined in 260 participants, including 160 patients with HFpEF and 100 control subjects without HF. Echocardiography was performed on all study participants. The patients with HFpEF were divided into class II, III, or IV according to the New York Heart Association (NYHA) classification.

RESULTS

The MAU levels in the HFpEF group were significantly higher than those in the non-HF group (58.97 ± 89.84 vs. 19.56 ± 29.34, p > 0.05). However, there was no significant difference in the levels of MAU among NYHA class II-IV patients in the HFpEF group (p > 0.05). In Pearson linear correlation analysis, MAU levels in the HFpEF group were positively correlated with left atrial diameter (LAD; r = 0.344, p < 0.05), but negatively correlated with hemoglobin (r = - 0.233, p < 0.05). The area under the ROC curve (AUC) of MAU for the diagnosis of HFpEF was 0.83 (95% CI [0.76, 0.90], p < 0.05), the sensitivity was 72.50%, and the specificity was 82.0%. The AUC of NT-proBNP was 0.88 (95% CI [0.83, 0.94], p < 0.05), the sensitivity was 82%, and the specificity was 73.8%. The AUC of MAU combined with NT-proBNP was 0.91 (95% CI [0.86, 0.96], p < 0.05).

CONCLUSION

Our results show that MAU can be used as a biomarker for the diagnosis of HFpEF. Combined detection of MAU with NT-proBNP has clinical value in improving the accuracy of diagnosis of HFpEF. However, there is no significant correlation between MAU levels and the severity of HFpEF.

Prognostic value of serum albumin-to-creatinine ratio in patients with acute myocardial infarction: Results from the retrospective evaluation of acute chest pain study

The long-term association between serum albumin-to-creatinine ratio (sACR) and poor patient outcomes in acute myocardial infarction (AMI) remains unclear. This study aimed to determine whether sACR was a predictor of poor long-term survival in patients with AMI.This was a study of patients with AMI in the emergency department (ED) from the retrospective multicenter study for early evaluation of acute chest pain (REACP) study. The patients were categorized into tertiles (T1, T2, and T3) based on the admission sACR (0.445 and 0.584 g/μmol). Baseline sACR at admission to the ED was predictive of adverse outcomes. The primary outcome was all-cause mortality within the follow-up period. Cox proportional hazards models were performed to investigate the association between sACR and all-cause mortality in patients with AMI.A total of 2250 patients with AMI were enrolled, of whom 229 (10.2%) died within the median follow-up period of 10.7 (7.2-14.6) months. Patients with a lower sACR had higher all-cause mortality and adverse outcomes rates than patients with a higher sACR. Kaplan-Meier survival analysis showed that patients with a higher sACR had a higher cumulative survival rate (P < .001). Cox regression analysis showed that a decreased sACR was an independent predictor of all-cause mortality [T2 vs T1: hazard ratio (HR); 0.550, 95% confidence interval (95% CI), 0.348-0.867; P = .010 and T3 vs T1: HR, 0.305; 95% CI, 0.165-0.561; P < .001] and cardiac mortality (T2 vs T1: HR, 0.536; 95% CI, 0.332-0.866; P = .011 and T3 vs T1: HR, 0.309; 95% CI, 0.164-0.582, P < .001).The sACR at admission to ED was independently associated with adverse outcomes, indicating that baseline sACR was a useful biomarker to identify high-risk patients with AMI at an early phase in ED.

Albuminuria as a Predictor of Cardiovascular Outcomes in Patients With Acute Myocardial Infarction

Background In patients with myocardial infarction ( MI ), reduced kidney function is recognized as an important predictor of poor prognosis, but the impact of albuminuria, a representative measure of kidney damage, has not been extensively evaluated. Methods and Results In the SCREAM (Stockholm Creatinine Measurements) project (2006-2012), we identified 2469 patients with incident MI with dipstick proteinuria measured within a year before MI (427 patients also had urine albumin to creatinine ratio [ ACR ] measured concurrently) and obtained estimates for ACR with multiple imputation in participants with data solely on dipstick proteinuria. We quantified the association of ACR with the post- MI composite and individual outcomes of all-cause mortality, cardiovascular mortality, recurrent MI , ischemic stroke, or heart failure using Cox models and then evaluated the improvement in C statistic. During a median follow-up of 1.0 year after MI , 1607 participants (65.1%) developed the post- MI composite outcome. Higher ACR levels were independently associated with all outcomes except for ischemic stroke. Per 8-fold higher ACR (eg, 40 versus 5 mg/g), the hazard ratio of composite outcome was 1.21 (95% CI , 1.08-1.35). The addition of the ACR improved the C statistic of the post- MI composite by 0.040 (95% CI, 0.030-0.051). Largely similar results were obtained regardless of diabetic status and when ACR or dipstick was separately analyzed without imputation. Conclusions In patients with MI , albuminuria was a potent predictor of subsequent outcomes, suggesting the importance of paying attention to the information on albuminuria, in addition to kidney function, in this high-risk population.

Body mass index and albumin levels are prognostic factors for long-term survival in elders with limited performance status

Elderly long-term care facility residents typically have musculoskeletal conditions that may lead to long-term disability and increased mortality. Our main objective was to explore the relationship between body mass index (BMI), albumin levels, and mortality in elderly individuals with limited performance status. Among 182 participants (mean age, 78.8 years; 57% women), 11%, 64%, and 25% had serum albumin levels of <2.8, 2.8-3.5, and >3.5 g/dL, respectively. After multivariate adjustments, diastolic blood pressure >90 mmHg was associated with all-cause mortality [hazard ratio (HR) = 2.08, 95% confidence interval (CI) = 1.13-3.82; P = 0.018]. In addition, BMI <18.5 kg/m2 and albumin level <2.8 g/dL associated with higher mortality than BMI = 18.5-24 kg/m2 and albumin level > 3.5 g/dL (HR = 1.80, 95% CI = 1.11-2.94 and HR = 2.54, 95% CI 1.22-5.30, respectively; P = 0.018 and 0.013, respectively). Highest mortality was noted in participants with albumin levels <2.8 g/dL and BMIs <18.5 kg/m2 (HR = 6.12, 95% CI = 1.85-20.21, P = 0.003). Combined hypoalbuminemia (albumin level < 2.8 g/dL) and low BMI (<18.5 kg/m2) may be a useful prognostic indicator of high mortality risk in elderly individuals with limited performance status.

Neoplastic disease after acute coronary syndrome: incidence, duration, and features: the ABC-4* Study on Heart Disease

AIM

To investigate the clinical features and incidence of malignant neoplasia during 17 years of follow-up in an unselected sample of patients with acute coronary syndrome (ACS).

METHODS

The Adria, Bassano, Conegliano, and Padova Hospital-4 Study on Heart Disease is an ongoing, prospective study of an unbiased population of patients with ACS. Baseline clinical and laboratory data were obtained during the first 7 days of hospitalization at three different intensive coronary care units. The current study included data from 589 patients with ACS.

RESULTS

At enrollment, 19 patients had confirmed neoplasia. During follow-up, 99 additional patients developed malignant neoplastic disease. The incidence rate was 17.8 cases per 1000 person-years, which was about three times higher than that observed in the general population. Patients had a shorter duration of neoplasia when they developed it after enrollment compared with those with preexisting neoplasia [hazard ratio = 2.0 (1.5-2.6), P = 0.001]. Patients with neoplasia who died during follow-up had an earlier onset of neoplasia [hazard ratio = 1.8 (1.1-2.9), P = 0.01] and shorter duration than survivors [hazard ratio = 4.1 (2.4-7.0), P < 0.0001]. The estimated time to diagnosis of neoplasia indicated elderly patients had a significantly higher risk than younger people during the 17 years of follow-up. After the onset of neoplasia, survival time declined more sharply in the elderly than younger people.

CONCLUSION

The long-term prospective study showed that patients with ACS have a higher incidence of malignancy than the general population. Those who develop neoplasm after being diagnosed with ACS have a worse prognosis than patients with a preexisting neoplasia.

Qiliqiangxin Protects against Renal Injury in Rat with Cardiorenal Syndrome Type I through Regulating the Inflammatory and Oxidative Stress Signaling

Cardiorenal syndrome (CRS) is a frequently encountered clinical condition when the dysfunction of either the heart or kidneys amplifies the failure progression of the other organ. CRS remains a major global health problem. Qiliqiangxin (QLQX) is a traditional Chinese herbs medication, which can improve cardiac function, urine volume, and subjective symptoms in patients with chronic heart failure. In the present study, we aim to investigate the role of QLQX in the treatment of CRS type I and the possible mechanism through establishment of a rat model of myocardial infarction. Rats in CRS-Q group were orally treated with QLQX daily for 2 weeks or 4 weeks, while in sham group and CRS-C group were treated with saline at the same time. Enzyme-linked immunosorbent assay (ELISA) analysis showed that QLQX significantly reduced the levels of angiotensin II (AngII), brain natriuretic peptides (BNP), creatinine (CRE), cystatin C (CysC), tumor necrosis factor (TNF)-α, interleukin (IL)-6, microalbuminuria (MAU), and neutrophil gelatinase-associated lipocalin (NGAL) in plasma induced by myocardial infarction. Western blot analysis showed that QLQX significantly reduced the expressions of AngII, non-phagocytic cell oxidase (NOX)2, and B-cell lymphoma (Bcl)2 associated X protein (Bax), and increased the expressions of Bcl2 and Angiotensin II Type 1 receptor (ATR) in the kidney as compared with the CRS-C group. Fluorescence microscopy showed that the content of reactive oxygen species (ROS) was significantly reduced in the kidney as compared with the CRS-C group. We also examined the apoptosis level in kidney by using terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) staining, and the result showed that QLQX significantly reduced the apoptosis level in kidney induced by myocardial infarction. Taken together, we suggest that QLQX may be a potentially effective drug for the treatment of CRS by regulating inflammatory/oxidative stress signaling.

Microalbuminuria could improve risk stratification in patients with TIA and minor stroke

Objective

Transient ischemic attacks (TIA) and minor strokes are important risk factors for recurrent strokes. Current stroke risk prediction scores such as ABCD2, although widely used, lack optimal sensitivity and specificity. Elevated urinary albumin excretion predicts cardiovascular disease, stroke, and mortality. We explored the role of microalbuminuria (using albumin creatinine ratio (ACR)) in predicting recurrence risk in patients with TIA and minor stroke.

Methods

Urinary ACR was measured on a spot sample in 150 patients attending a daily stroke clinic with TIA or minor stroke. Patients were followed up at day 7, 30, and 90 to determine recurrent stroke, cardiovascular events, or death. Eligible patients had a carotid ultrasound Doppler investigation. High‐risk patients were defined as those who had an event within 90 days or had >50% internal carotid artery (ICA) stenosis.

Results

Fourteen (9.8%) recurrent events were reported by day 90 including two deaths. Fifteen patients had severe ICA stenosis. In total, 26 patients were identified as high risk. These patients had a higher frequency of previous stroke or hypercholesterolemia compared to low‐risk patients (P = 0.04). ACR was higher in high‐risk patients (3.4 [95% CI 2.2–5.2] vs. 1.7 [1.5–2.1] mg/mmol, P = 0.004), independent of age, sex, blood pressure, diabetes, and previous stroke. An ACR greater than 1.5 mg/mmol predicted high‐risk patients (Cox proportional hazard ratio 3.5 (95% CI 1.3–9.5, P = 0.01).

Interpretation

After TIA or minor stroke, a higher ACR predicted recurrent events and significant ICA stenosis. Incorporation of urinary ACR from a spot sample in the acute setting could improve risk stratification in patients with TIA and minor stroke.

Protective effects of naringenin in cardiorenal syndrome

BACKGROUND

Cardiorenal syndrome is a complicated and bidirectional interrelationship between the heart and kidneys. Naringenin (NG) is a naturally occurring flavonoid possessing various biological and pharmacological properties.

MATERIALS AND METHODS

We tested whether NG could improve cardiac and renal function in a rat model of cardiorenal syndrome.

RESULTS

The results showed that NG-attenuated cardiac remodeling and cardiac dysfunction in rats with cardiorenal syndrome, as evidenced by decrease of left ventricle weight (LVW), increase of body weight (BW), decrease of LVW/BW, decrease of concentrations of serum creatinine, blood urea nitrogen, type-B natriuretic peptide, aldosterone, angiotensin (Ang) II, C-reactive protein, and urine protein, increase of left ventricular systolic pressure and falling rates of left ventricular pressure (dp/dtmax), and decrease of left ventricular diastolic pressure, left ventricular end-diastolic pressure, and -dp/dtmax. NG significantly inhibited the increase of lipid profiles including low-density lipoprotein, TC, and TG in rats. In addition, NG significantly inhibited the increase of cardiac expression of IL-1β, IL-6, and interferon γ. Moreover, NG decreased malonaldehyde level, increased superoxide dismutase activity and glutathione content in rats, and increased the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and catalytic subunit of γ-glutamylcysteine ligase (GCLc) in rats and Ang II-treated cardiac fibroblasts. Inhibition of Nrf2 and glutathione synthesis significantly suppressed NG-induced decrease of ROS level. Inhibition of Nrf2 markedly suppressed NG-induced increase of GCLc expression in Ang II-treated cardiac fibroblasts.

CONCLUSIONS

The data provide novel options for therapy of patients and new insights into the cardioprotective effects of NG in cardiorenal syndrome.

The predictive value of proteinuria in acute pancreatitis

BACKGROUND/OBJECTIVES

Acute pancreatitis has a highly variable clinical course. Early and reliable predictors for the severity of acute pancreatitis are lacking. Proteinuria appears to be a useful predictor of disease severity and outcome in a variety of clinical conditions. This study aims to investigate the predictive value of proteinuria on admission for the severity of acute pancreatitis compared with other commonly used predictors; the APACHE II score, Modified Glasgow score and C-reactive protein (CRP).

METHODS

This is a post-hoc analysis of 64 patients admitted with acute pancreatitis treated in one teaching hospital, who participated in a previous randomized trial. Proteinuria was defined as a Protein/Creatinine (P/C) ratio >23 mg/mmol. The primary endpoint was severe acute pancreatitis. Secondary endpoints included infectious complications, need for invasive intervention, ICU stay and in-hospital mortality.

RESULTS

Proteinuria was present in 30/64 patients (47%). Eleven patients (17%) had severe acute pancreatitis. There was no difference in incidence of severe acute pancreatitis between patients with and without proteinuria: 6/30 patients (20%) versus 5/34 patients (15%) respectively (p = 0.58). Likewise, the occurrence of infectious complications, need for intervention and ICU stay and mortality did not differ significantly (p = 0.58, p = 0.99, p = 0.33 and p = 0.60 respectively). The diagnostic performance of the P/C ratio for the prediction of severe pancreatitis was inferior to the Modified Glasgow score (p = 0.04) and CRP (p = 0.03).

CONCLUSION

Proteinuria on admission does not seem to be a reliable predictor for disease severity in acute pancreatitis. The diagnostic performance of the P/C ratio is inferior to the Modified Glasgow score and CRP.

Type of β-blocker use among patients with versus without diabetes after myocardial infarction

BACKGROUND

Discharge β-blocker prescription after myocardial infarction (MI) is recommended for all eligible patients. Numerous β-blocker choices are presently available with variable glycometabolic effects, which could be an important consideration in patients with diabetes mellitus (DM). Whether patients with DM preferentially receive β-blockers with favorable metabolic effects after MI and if this choice is associated with better glycemic control postdischarge is unknown.

METHODS

Among patients from 24 US hospitals enrolled in an MI registry (2005-2008), we investigated the frequency of "DM-friendly" β-blocker prescription at discharge by DM status. β-Blockers were classified as DM-friendly (eg, carvedilol and labetalol) or non-DM-friendly (eg, metoprolol and atenolol), based on their effects on glycemic control. Hierarchical, multivariable logistic regression examined the association of DM with DM-friendly β-blocker use. Among DM patients, we examined the association of DM-friendly β-blockers with worsened glycemic control at 6 months after MI.

RESULTS

Of 4,031 MI patients, 1,382 (34%) had DM. β-Blockers were prescribed at discharge in 93% of patients. Diabetes mellitus-friendly β-blocker use was low regardless of DM status, although patients with DM were more likely to be discharged on a DM-friendly β-blocker compared with patients without DM (13.5% vs 10.3%, P = .003), an association that remained after multivariable adjustment (odds ratio 1.41, 95% CI 1.13-1.77). There was a trend toward a lower risk of worsened glucose control at 6 months in DM patients prescribed DM-friendly versus non-DM-friendly β-blockers (Relative Risk 0.80, 95% CI 0.60-1.08).

CONCLUSION

Most DM patients were prescribed non-DM-friendly β-blockers-a practice that was associated with a trend toward worse glycemic control postdischarge. Although in need of further confirmation in larger studies, our findings highlight an opportunity to improve current practices of β-blockers use in patients with DM.

Urinary albumin concentration and long-term cardiovascular risk in acute coronary syndrome patients: a PROVE IT-TIMI 22 substudy

Albuminuria has been shown to be associated with mortality and cardiovascular events, independent of traditional cardiovascular risk factors. This suggests that albuminuria may not just represent glomerular damage, but may be a marker of more diffuse endothelial dysfunction. We investigated the relationship between urinary albumin levels after an acute coronary syndrome and cardiovascular outcomes in statin treated subjects after acute coronary syndromes (ACS). Furthermore we assessed the effect of intensive statin treatment on albuminuria among patients in the PROVE IT-TIMI 22 trial, in which patients who had been hospitalized with ACS were randomized to pravastatin 40 mg (standard therapy) or atorvastatin 80 mg daily (intensive therapy). In univariate analyses, increasing urine albumin concentration was associated with increased risk of myocardial infarction, stroke, heart failure, and composite of death, myocardial infarction and stroke at 2 years. However, in a multivariable model containing traditional cardiovascular risk factors, albuminuria was not an independent predictor of the primary PROVE IT endpoint of death, myocardial infarction, unstable angina, revascularization and stroke, and was only an independent predictor of all-cause mortality at urinary albumin concentration >300 mcg/ml. There was no significant change in urinary albumin concentration from enrolment to end of study in either the standard or intensive statin therapy groups, and no significant difference between treatment groups. Our results suggest that after an acute coronary syndrome in statin treated patients, microalbuminuria may reflect traditional cardiovascular risk factor burden and offer little prognostic information independent of those factors.

The role of albuminuria as a non-invasive marker for congestive acutely decompensated chronic heart failure and the spironolactone effect in elderly Portuguese: a non-randomized trial

BACKGROUND/OBJECTIVES

Albuminuria is a robust, validated cardiovascular risk factor. It is a simple and widely available test that was shown to be a powerful and independent predictor of prognosis in chronic heart failure. Mineralocorticoid receptor antagonists may reduce the acute and chronic harmful effects of mineralocorticoid receptor activation on the kidney. The objectives of the trial were to compare the effect of spironolactone versus standard acutely decompensated heart failure (ADHF) therapy on albuminuria and to investigate the role of albuminuria as a prognostic marker in patients with ADHF.

METHODS

Secondary analysis of a prospective, interventional study including 100 patients with ADHF. Fifty patients were non-randomly assigned to spironolactone 100 mg/day plus standard ADHF therapy (intervention group) or standard ADHF therapy alone (control group).

RESULTS

Patients in control group were older, had higher creatinine and urea levels, and had higher proportion of microalbuminuria (all, P < 0.05). Paired comparison of baseline and day 3 log albuminuria within each group, showed a more pronounced decrease in the intervention group (1.79 ± 0.75 to 1.59 ± 0.67, P = 0.003 vs 1.89 ± 0.70 to 1.79 ± 0.74, P = 0.096). In addition, the proportion of patients with normoalbuminuria increased from baseline to day 3 in spironolactone group (20 (40%) to 27 (54%), P < 001), accordingly the number of patients in the micro and macroalbuminuria groups was reduced. Day 1 albuminuria was positively correlated with day 1 N-terminal pro-brain natriuretic peptide (0.260 [0.105-0.758], P = 0.009).

CONCLUSIONS

High-dose spironolactone added to standard ADHF therapy is likely to induce a more pronounced albuminuria decrease and a significant reduction in the proportion of micro and macroalbuminuria.

Early evolution and correlates of urine albumin excretion in patients presenting with acutely decompensated heart failure

BACKGROUND

Urine albumin excretion is an important predictor of adverse cardiovascular events in various populations. Its correlation in patients with acute heart failure has not been described.

METHODS AND RESULTS

This prospective, observational study included 115 patients presenting with acute heart failure. The urine albumin/creatinine ratio (UACR) was measured from spot urine samples collected on days 1 and 7 of hospitalization. Median UACR decreased from 83 to 22 mg/gCr on days 1 and 7, respectively (P<0.0001). The proportion of patients with normoalbuminuria (UACR <30 mg/gCr) increased from 31% on day 1 to 60% on day 7, whereas the proportion with microalbuminuria (UACR between 30 and 299 mg/gCr) and macroalbuminuria (UACR ≥300 mg/gCr) decreased, respectively, from 42% and 27% on day 1 to 30% and 10% on day 7 (P<0.0001). These changes in UACR were correlated with changes in serum bilirubin and N-terminal pro b-type natriuretic peptide concentrations (correlation coefficients 1.087 and 0.384, respectively; 95% confidence interval, 0.394-1.781 and 0.087-0.680, respectively; and P=0.003 and 0.013, respectively), although they were not correlated with change in estimated glomerular filtration rate.

CONCLUSIONS

In this sample of patients presenting with acute heart failure, urine albumin excretion was often increased at admission to the hospital and decreased significantly within 7 days of treatment. The decrease was correlated with serum N-terminal pro b-type natriuretic peptide and bilirubin concentrations, although neither with baseline nor with changes in indices of renal function.

Microalbuminuria in non-diabetic STEMI: an independent predictor for acute kidney injury

AIMS

To assess the impact of microalbuminuria on the development of acute kidney injury and to investigate its prognostic role at long term follow-up in 526 consecutive patients with ST elevation myocardial infarction without previously known diabetes.

METHODS

Microalbuminuria was measured using immunonephelemetry in the urine collected in the night.

RESULTS

Patients with microalbuminuria were older (p = 0.013). They showed higher values of peak glycemia (p = 0.017), peak Tn I (p < 0.001), NT-pro BNP (p = 0.020), ESR (p = 0.003), CRP (p = 0.020), and leukocyte count (p < 0.001). Lower eGFR was observed in patients with microalbuminuria both on admission and during ICCU stay (p = 0.048 and p = 0.003, respectively). A positive correlation was observed between CRP and microalbuminuria (Spearman's rho 0.114, p = 0.024). The composite end point was observed in 73 patients (18 patients died and 59 patients developed acute kidney injury). At multivariable regression analysis, microalbuminuria was an independent predictor of acute kidney injury. At follow-up [42.6 (25th-75th percentile, 17.5-56.8) months], Kaplan-Meier curve analysis showed that patients with microalbuminuria had a lower survival rate in respect to patients without microalbuminuria. Cox regression analysis documented that microalbuminuria was an independent predictor of long term mortality (HR: 1.089; 97% CI 1.036-1.145; p < 0.001).

CONCLUSIONS

In a large series of STEMI patients without previously known diabetes submitted to PCI, microalbuminuria, as a marker of endothelial permeability following higher systemic inflammatory activation and larger infarct lesions, is an independent predictor for the development acute kidney injury. Furthermore, microalbuminuria identifies a subset of patients at higher risk for long term mortality.

Metabolic syndrome influencing infarct size and heart failure in patients with acute coronary syndrome: does gender matter?

Metabolic syndrome (MetS) is the occurrence of diabetes mellitus/glucose intolerance, arterial hypertension, central obesity, dyslipidemia, and microalbuminuria in the same patient (definition by WHO). Presence of metabolic syndrome is associated with larger myocardial infarction size and complications following acute myocardial infarction. Two hundred and thirty patients with acute coronary syndromes were analyzed. Those with MetS (n=141) included patients with diabetes mellitus/glucose intolerance and at least two of the following criteria: hypertension, hypertriglyceridemia/low HDL cholesterol, android obesity/body mass index (BMI) ≥ 30, or microalbuminuria. Control group did not meet criteria for MetS. Presence of heart failure was assigned according to Killip classification. The MetS group had larger myocardial infarction size determined by peak creatine-kinase (CK) (1484±1354 vs. 981±890, p = 0.003) and CK MB (141±117 vs. 95±78, p = 0.002). While in non-MetS group males had larger myocardial infarction than females, in MetS group females had larger myocardial infarction than males. Cardiac failure occurred more in MetS group of patients, again was more prominent in females. Occurrence of metabolic syndrome in acute coronary syndrome patients predisposes to larger myocardial infarction size, more on the account of female patients having MetS. MetS, again particularly in females, predisposes to higher chance of having heart failure during acute coronary syndrome. Recognizing the female group with MetS as of higher risk for large myocardial infarction and heart failure leads us to pay special attention on this patient population.

Prevalence of microalbuminuria in hypertensive patients and its associated cardiovascular risk in clinical cardiology: Moroccan results of the global i-SEARCH survey - a sub-analysis of a survey with 21,050 patients in 26 countries worldwide

Objectives

To determine the prevalence of microalbuminuria (MAU) in hypertensive outpatients visiting a cardiologist’s office or clinic and to describe the relationship between MAU and cardiovascular risk factors.

Methods

This was an international, observational, cross-sectional study of 22 282 patients, with 457 subjects from Morocco in 40 cardiology centres. Inclusion criteria were: male and female outpatients aged ≥ 18 years with currently treated or newly diagnosed hypertension (≥ 140/90 mmHg at rest on the day of the study visit) and no reason for false positive microalbuminuria dipstick tests.

Outcome measures

Prevalence of microalbuminuria assessed using a dipstick test, co-morbid cardiovascular risk factors or disease and their relationship with the presence of MAU, and role of pharmacotherapy in modulating the prevalence of MAU.

Results

The prevalence of microalbuminuria in hypertensive patients in Morocco (67.8%) was high compared to the worldwide prevalence (58.3%). Despite the fact that all physicians regarded MAU as important for risk assessment and therapeutic decisions, routine MAU measurement was performed in only 35% of the practices. In clinical cardiology, MAU is highly correlated with a wide variety of cardiovascular risk factors and cardiovascular disease.

While angiotensin receptor blockers (ARBs) appeared to be associated with the lowest risk of MAU, calcium channel blockers (CCBs) were more often used in this patient group.

Conclusions

Hypertensive, high-risk cardiovascular patients are common in clinical cardiology. Given the high prevalence detected, screening of MAU in addition to more aggressive multi-factorial treatment to reduce blood pressure as well as other cardiovascular risk factors is required.

Albuminuria: pathophysiology, epidemiology and clinical relevance of an emerging marker for cardiovascular disease

Albuminuria has emerged from being a sign of early kidney disease in diabetes to an independent predictor of cardiovascular risk. Epidemiological studies suggest that microalbuminuria (30-300 mg/d) is present in 5-19% of the general population, in up to 23% of patients with hypertension and in up to 40% of patients with diabetes. Recent data suggest an even higher prevalence in certain patient populations. As it is associated with a variety of important cardiovascular risk factors, including prediabetes, dyslipidemia and the metabolic syndrome, detection of albumin in the urine represents an important diagnostic window for systemic micro- or macrovascular damage. Various studies have demonstrated the predictive value of all levels of albuminuria for future cardiovascular events in patients with diabetes, hypertension or overt cardiovascular disease, as well as in the general population. Annual screening for microalbuminuria is now recommended by international diabetes guidelines for patients with diabetes, and may be appropriate for nondiabetics with risk factors for cardiovascular disease.

The relation between microalbuminuria and coronary collateral vessel development in patients with unstable coronary artery disease

Microalbuminuria, considered a marker for systemic vascular disease, is a significant predictor of increased risk for cardiovascular morbidity and mortality in the general population. The relationship between microalbuminuria and cardiovascular disease is unknown. The aim of this study is to examine the association between microalbuminuria and coronary collateral vessel (CCV) development in nondiabetic and nonhypertensive patients with unstable coronary artery disease (USCAD). One hundred and six patients that had USCAD without hypertension and diabetes participated in the study. Microalbuminuria was assessed by radioimmunoassay in 24-h urine collections performed on the first day, and coronary angiography was performed 2-4 days after admissions. In total, 26 patients (mean age 56+/-14 years) had the criteria of the microalbuminuria group and 80 patients with normoalbuminuria (mean age 59+/-11 years), who had one or more diseased vessels with 80% or more stenosis, were included in the control group. The CCVs are graded according to the Rentrop scoring system and a Rentrop grade >or=1 was accepted as CCV development. CCV development was detected in eight (23%) of 26 patients in the microalbuminuria group and in 53 (74%) of 80 patients in the normoalbuminuria group. CCV development in the patients in the normoalbuminuria group was significantly different from that of the patients in the microalbuminuria group (r = -0.15, P = 0.006). In conclusion, these findings suggest that CCV development is poorer in the microalbuminuria group than the normoalbuminuria group. This study shows that in patients with USCAD, microalbuminuria, which is related to systemic vascular disease, affects CCV development negatively.

Angiotensin blockade to reduce microvascular damage in diabetes mellitus

BACKGROUND

Diabetic retinopathy and microalbuminuria are often thought of as distinct disease entities despite their common pathophysiology. Many studies have addressed the prognostic significance of these conditions and their treatment.

METHODS

Medline was selectively searched for articles published from 1948 to 2008 containing the terms "angiotensin," "microalbuminuria," and "retinopathy." The results were further amplified by screening the reference sections of the retrieved articles.

RESULTS

Diabetic retinopathy and microalbuminuria are expressions of microvascular damage. They are promoted by hypertension, hyperglycemia, dyslipidemia, and elevated levels of angiotensin II. They are treated by adjusting these risk factors to the near-normal range. In the IDNT study, angiotensin II blockade with irbesartan was found to lead to an absolute reduction of renal events by 7.4% as compared to standard treatment, and by 9.5% as compared to amlodipine. In the DIRECT study, candesartan reduced the progression of retinopathy by 13% and effected a regression by 34%. In the Steno-2 study, an intensive program of multifactorial risk reduction significantly lowered the rate of microvascular complications over a mean follow-up interval of 3.8 years (hazard ratios for different complications varying from 0.27 to 0.45). Over the longer term (13.3 years), this approach also led to a reduction of macrovascular events (HR 0.54 for mortality of all causes, 0.43 for cardiovascular mortality, and 0.41 for cardiovascular events).

CONCLUSIONS

Diabetic retinopathy and microalbuminuria are expressions of microvascular damage. They often appear together and point toward possible future macrovascular events. Multifactorial intervention can lessen the consequences of these pathological conditions.

Prognostic value of albuminuria on 1-month mortality in acute myocardial infarction

RATIONALE

An increase in albuminuria occurs in the early days after acute myocardial infarction. The aim of this study was to assess the relation between albuminuria and 30-day mortality, as well as its incremental predictive value, on top of established prognostic parameters.

METHODS AND RESULTS

Demographic, clinical, and biological characteristics at admission, as well as in-hospital treatments and 1-month survival, were recorded in 1,211 consecutive patients admitted for acute myocardial infarction. Albuminuria was assessed from an 8-hour overnight urine collection within the first 2 days using immunonephelemetry. The population was categorized into 3 groups according to albuminuria levels (<20, 20-200, and >200 microg/min). Among survivors on day 2, 52% (625/1,211) of patients had an albuminuria level <20 microg/min, 39% (477) between 20 and 200 microg/min, and 9% (109) >200 microg/min. High levels of albuminuria were associated with older age, peripheral vessel disease, systolic blood pressure, glucose, creatinine, troponin, B-type natriuretic peptide, and high-sensitivity C reactive protein levels, as well as use of angiography, angiotensin-converting enzyme inhibitors, and beta blockers. At 1 month, there was a significantly higher mortality rate in groups with higher albuminuria. After adjustment for baseline characteristics, patients with albuminuria level of >20 microg/min had a 2.7-fold higher 30-day mortality, and those with >200 microg/min had an almost 4-fold higher 30-day mortality compared to those with albuminuria level of <20 microg/min. The addition of albuminuria information improved the discrimination capacity of the model and the global risk prediction.

CONCLUSIONS

Albuminuria level, taken as a quantitative or categorical variable, is an independent and powerful predictor of mortality after acute myocardial infarction.

Usefulness of proteinuria as a prognostic marker of mortality and cardiovascular events among patients undergoing percutaneous coronary intervention (data from the Evaluation of Oral Xemilofiban in Controlling Thrombotic Events [EXCITE] trial)

Proteinuria was associated with cardiovascular events and mortality in community-based cohorts. The association of proteinuria with mortality and cardiovascular events in patients undergoing percutaneous coronary intervention (PCI) was unknown. The association of urinary dipstick proteinuria with mortality and cardiovascular events (composite of death, myocardial infarction, or nonhemorrhagic stroke) in 5,835 subjects of the EXCITE trial was evaluated. Dipstick urinalysis was performed before PCI, and proteinuria was defined as trace or greater. Subjects were followed up for 210 days/7 months after enrollment for the occurrence of events. Multivariate Cox regression analysis evaluated the independent association of proteinuria with each outcome. Mean age was 59 years, 21% were women, 18% had diabetes mellitus, and mean estimated glomerular filtration rate was 90 ml/min/1.73 m(2). Proteinuria was present in 750 patients (13%). During follow-up, 22 subjects (2.9%) with proteinuria and 54 subjects (1.1%) without proteinuria died (adjusted hazard ratio 2.83, 95% confidence interval [CI] 1.65 to 4.84, p <0.001). The severity of proteinuria attenuated the strength of the association with mortality after PCI (low-grade proteinuria, hazard ratio 2.67, 95% CI 1.50 to 4.75; high-grade proteinuria, hazard ratio 3.76, 95% CI 1.24 to 11.37). No significant association was present for cardiovascular events during the relatively short follow-up, but high-grade proteinuria tended toward increased risk of cardiovascular events (hazard ratio 1.45, 95% CI 0.81 to 2.61).In conclusion, proteinuria was strongly and independently associated with mortality in patients undergoing PCI. These data suggest that such a relatively simple and clinically easy to use tool as urinary dipstick may be useful to identify and treat patients at high risk of mortality at the time of PCI.

Albumin excretion in acute myocardial infarction: a guide for long-term prognosis

BACKGROUND

Albumin excretion rate has been found to be associated with increased risk of mortality in several clinical settings. We assessed the relationship between urinary albumin and 7-year mortality in a cohort of patients with acute myocardial infarction (AMI).

METHODS

In this prospective study, we examined 505 white patients admitted with AMI to the intensive care unit of 3 hospitals. Main end points were nonearly all-cause and cardiovascular (CV) mortality. Albumin-to-creatinine ratio (ACR) was measured by radioimmunoassay on the first, third, and seventh days after admission. Risk estimates were made using Cox proportional-hazard model and relative odds. Forty patients (7.9%) died early inhospital, and 175 (34.7%) died during the rest of the follow-up (nonearly mortality).

RESULTS

The ACR measured on the third day predicted the occurrence of 7-year nonearly all-cause and CV mortality. Hazard ratios for ACR > or =0.97 mg/mmol were 3.0 (95% confidence limit 2.2-4.1), P < .0001, for nonearly all-cause mortality and 3.5 (95% confidence limit 2.5-5.0), P < .0001, for CV mortality. Correspondent fully adjusted hazard ratios were 1.9 (95% CI 1.4-2.6), P < .0001, and 2.2 (95% CI 1.5-3.2), P < .0001, respectively. By adding ACR to the 18-variable predictive model, ACR improved significantly both the goodness of fitting of the model for nonearly all-cause (P < .0001) and CV mortality (P < .0001) and the C-statistic value (P < .0001 and P = .002 for nonearly all-cause and CV mortality, respectively). Similar results were obtained for ACR measured on the first day or the seventh day.

CONCLUSIONS

An early increase of urinary albumin in AMI is a strong independent predictor of long-term adverse clinical outcome. The ACR improved clinical prediction over and above baseline traditional multivariable risk models.

Importance of low-grade albuminuria

The well-described association between chronic kidney disease and cardiovascular disease is typically thought to originate from loss of renal function, as estimated by the glomerular filtration rate. However, recent data suggest that urinary albumin excretion has an important role in this association. Albuminuria is a marker of underlying vascular dysfunction and has been correlated with structural and functional integrity of the vasculature. Although the traditional upper limit of normal daily albumin excretion has been 30 mg/d, recent epidemiologic data suggest that levels in the general population are actually much lower. Further, within this range of low-grade albuminuria (LGA), increasing excretion rates are associated with increasing risk of cardiovascular disease. This association is independent of renal function, and in the earliest stages of chronic kidney disease, LGA seems to be a more important determinant than the glomerular filtration rate. This emerging association underscores the complexity of albumin excretion, in which subtle changes in albumin excretion reflect widespread vascular processes. Using the key words albuminuria, low-grade albuminuria, and microalbuminuria in a PubMed search of literature from January 1, 1995, to February 29, 2008, this review summarizes the most recent data on LGA and its association with cardiovascular and renal disease.

Low-grade albuminuria and cardiovascular risk : what is the evidence?

Microalbuminuria (MA), conventionally defined as a urinary albumin excretion (UAE) of 30-300 mg/day, is recognised as a marker of endothelial dysfunction. Furthermore, it represents an established risk factor for cardiovascular morbidity and mortality and for end-stage renal disease in individuals with an adverse cardiovascular risk profile. It is common in the general population, particularly in patients with diabetes mellitus or arterial hypertension. There is growing evidence from prospective observational trials that UAE levels well below the current MA threshold ("lowgrade MA") are also associated with an increased risk of incident cardiovascular disease and allcause mortality. Even in apparently healthy individuals (without diabetes or hypertension), such an association has been shown. As albuminuria screening assays that are reliable even in the lower ranges are commercially available, there may be an important clinical role for MA in disease screening, comparable to the role of blood pressure and lipid screening. MA is modifiable, and the inhibition of the renin-angiotensin system by ACE inhibitors and AT1 receptor antagonists has been shown to result in a lower incidence of cardiovascular events.

Urinary excretion of alpha1-microglobulin and albumin in acute myocardial infarction. Correlation with plasma concentrations of troponin I and C-reactive protein

OBJECTIVES

Microalbuminuria associated with myocardial infarction (MI) is normally ascribed to glomerular factors, but could just as well involve pathophysiological processes located in other parts of the nephron, e.g. proximal tubules where plasma albumin normally filtered through the glomerulus is almost completely reabsorbed. The aims of this study were to establish whether impaired tubular reabsorption of filtered albumin contributes to microalbuminuria during MI, and whether the urinary excretion of protein relates to plasma levels of C-reactive protein (CRP) and troponin I.

MATERIAL AND METHODS

We monitored plasma CRP and troponin I as well as the urinary excretion of albumin and alpha1-microglobulin, a low-molecular-weight plasma protein and marker of tubular proteinuria, in 18 patients with MI.

RESULTS AND CONCLUSIONS

The urinary excretion of alpha1-microglobulin and albumin was significantly elevated in nine patients, and the urinary excretion of the two proteins correlated significantly. A decrease in tubular reabsorption of albumin may thus be at least one of the causative factors underlying microalbuminuria during MI. The plasma levels of CRP and troponin I were also significantly higher in this group of nine patients, and correlated with urinary protein excretion, suggesting an interrelationship between inflammatory response and tubular dysfunction. Extrarenal inflammatory processes seem to affect renal tubular function, thereby contributing to microalbuminuria during MI.

Does microalbuminuria predict illness severity in critically ill patients on the intensive care unit? A systematic review

CONTEXT

Studies assessing the accuracy of microalbuminuria to predict illness severity on the intensive care unit have produced inconsistent results.

OBJECTIVE

To determine the diagnostic accuracy of microalbuminuria to predict illness severity in critically ill patients on the intensive care unit.

DATA SOURCE

MEDLINE (1951 to September 2004) and EMBASE (1980 to September 2004) electronic databases were searched for relevant studies. Reference lists of all abstracts were manually searched to identify studies not included in the electronic database.

STUDY SELECTION

Studies that prospectively evaluated the accuracy of microalbuminuria to predict illness severity and/or mortality probability in adult patients on the intensive care unit were selected.

DATA EXTRACTION

We included nine studies in the review. Data to evaluate methodological quality and results were abstracted.

DATA SYNTHESIS

The methodological quality of a number of studies was poor. Significant heterogeneity in the design and conduct of the studies circumvented the data being subjected to meta-analysis. Studies also differed in the timing of the index test, in the methods of quantifying microalbuminuria, and in the cutoff values used.

CONCLUSIONS

This descriptive analysis reveals that microalbuminuria may hold promise as a predictor of illness severity and mortality on the intensive care unit. However, future epidemiologic studies need to be conducted to determine the optimal timing as well as the threshold reference value for the urine albumin creatinine ratio in the adult intensive care unit population. Thereafter, multiple-center prospective epidemiologic studies must be conducted to confirm and validate the findings of these preliminary studies. Future studies should conform to the Standards for Reporting of Diagnostic Accuracy checklist in terms of study design, conduct, and reporting. Presently there is no evidence to warrant the use of this tool on the intensive care unit.

Proteinuria is a prognostic marker for cardiovascular mortality: NIPPON DATA 80, 1980-1999

BACKGROUND: Proteinuria has been considered to be a prognostic marker for persons with diabetes mellitus, but only a limited number of studies about the relationship between proteinuria and mortality among general population has been available.

METHODS: The subjects were 10,897 individuals who participated in the National Cardiovascular Survey conducted in 1980 and who were aged 30 years or older living in 300 districts that had been randomly selected throughout Japan. The vital records were confirmed in 1999 and 7,203 subjects (3,180 males and 4,023 females) without a history of hypertension, stroke, heart disease, renal disease, or diabetes mellitus at the start of the study were investigated.

RESULTS: There were 126,825 person-years of follow-up. During the observed period of time, 371 died of cardiovascular causes, including 171 stroke deaths and 74 coronary deaths. The risk of proteinuria for cardiovascular mortality was greater than unity for those with a normal serum creatinine level, after adjusting for age and other cardiovascular disease risk factors.

CONCLUSIONS: When contrasted with other cardiovascular disease risk factors, urinary protein is an independent risk factor for cardiovascular death among the Japanese population.

What is the evidence that microalbuminuria is a predictor of cardiovascular disease events?

PURPOSE OF REVIEW

This review describes recently published studies evaluating the association between microalbuminuria and the development of cardiovascular disease events either in the presence of diabetes or hypertension, or in the population as a whole.

RECENT FINDINGS

Prospective studies confirm that microalbuminuria is predictive, independently of classical risk factors, of cardiovascular disease events and all-cause mortality within groups of patients with diabetes or hypertension and in the general population. However, these studies suggest that levels of albuminuria below the conventional cutoff point definition of microalbuminuria are significantly associated with cardiovascular morbidity and mortality. The pathophysiological mechanism underyling this association is still uncertain. Data from recent intervention studies suggest that treatment with angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers, as well as intensive multi-factorial intervention including behaviour modification and targeted pharmacotherapy in patients with microalbuminuria, offers significant reduction in cardiovascular and renal morbidity in people with albuminuria.

SUMMARY

Future absolute risk prediction scores for primary cardiovascular events could include microalbuminuria as a modifiable risk factor. The association between levels of albuminuria and cardiovascular outcomes in individuals within the normoalbuminuric range questions the current categorical definition of microalbuminuria. Intensive multifactorial interventions, including the use of agents that affect the renin-angiotensin pathway, are effective in reducing cardiovascular risk in patients with microalbuminuria and diabetes or hypertension.

Microalbuminuria: a strong predictor of 3-year adverse prognosis in nondiabetic patients with acute myocardial infarction

BACKGROUND

The aim of this study is to evaluate the significance of microalbuminuria (MA) as a 3-year prognostic index in nondiabetic patients with acute myocardial infarction (AMI).

METHODS

One hundred seventy-five patients with AMI were followed prospectively for 3 years. The study end point was cardiac death or rehospitalization for an acute coronary event.

RESULTS

Forty-two patients (24%) developed a new cardiac event during the follow-up. Microalbuminuria (P < .001), pulmonary edema during initial hospitalization (P < .001) and postinfarction angina (P = .0364), advanced age (P = .001), severe atherosclerosis (high Gensini score) (P = .036), ejection fraction <50% (P = .0013), history of bypass surgery (P = .0265), and early conservative management (P = .0214) were all associated with adverse prognosis. Cox proportional hazards regression analysis showed that MA was an independent predictor of 3-year adverse prognosis in all the models tested, with an adjusted relative risk for the development of a cardiac event ranging from 2.1 to 4.3.

CONCLUSIONS

In nondiabetic patients with AMI, MA is a strong and independent predictor of an adverse cardiac event within the next 3 years.

Urine albumin excretion in acute ischaemic stroke is related to serum interleukin-6

BACKGROUND AND PURPOSE

Several studies show a link between microalbuminuria and markers of inflammation. Increased urine albumin excretion accompanies acute ischaemic stroke. The mechanisms responsible for microalbuminuria in acute stroke patients remain unclear. The goal of this study was to determine if there is a relationship between urine albumin excretion and interleukin-6, a key mediator of acute phase reaction.

METHODS

Nineteen acute ischaemic stroke patients and 13 controls matched for age, sex and cardiovascular risk factors were included. Serum interleukin-6 level was measured on the 2nd day of stroke at 06:00 am, 10:00 am, 06:00 pm and 10:00 pm using ELISA method. Urine albumin excretion was determined using immunonephelometric method.

RESULTS

Interleukin-6 level and urine albumin excretion were significantly higher in stroke patients than in controls. There was a significant correlation between interleukin-6 level and urine albumin excretion in stroke patients (R = -0.60 at 06:00 am; R = -0.49 at 10:00 am; R = -0.64 at 06:00 pm; R = -0.54 at 10:00 pm) but not in controls.

CONCLUSIONS

Urine albumin excretion in acute ischaemic stroke is related to serum interleukin-6.

Albumin excretion in diabetic patients in the setting of acute myocardial infarction: association with 3-year mortality

AIMS/HYPOTHESIS

Diabetes mellitus is associated with increased mortality in subjects with acute myocardial infarction (AMI). We aimed to estimate the risk of mortality in AMI patients with and without diabetes using the urinary albumin : creatinine ratio (ACR).

METHODS

This is a prospective study of 121 consecutive, non-selected diabetic AMI patients, 121 age- and sex-matched non-diabetic AMI patients and 61 diabetic non-AMI outpatients as control subjects. All data were obtained during the first 7 days of hospitalisation and each AMI patient was followed for a period of exactly 3 years. Baseline ACR RIA measurements were made on the 1st, 3rd and 7th days of admission.

RESULTS

Adjusted ACR values were significantly higher in the diabetic AMI patients than in the diabetic control outpatients ( p<0.0001), and a significant difference was observed between the weekly ACR slopes for these two groups ( p<0.0001). Microalbuminuria was more prevalent in the diabetic AMI patients than in the non-diabetic AMI patients on the 1st day (62% vs 46%, p=0.01) and 3rd day (41% vs 29%, p=0.04). Among the AMI patients with normoalbuminuria (ACR <30 microg/mg), the mortality rate was 11.6% for the patients without diabetes and 33.8% for those with diabetes ( p=0.001). The mortality rate was much higher among the AMI patients with microalbuminuria (ACR >/=30 microg/mg) and similar for the diabetic (68.0%) and non-diabetic patients (74.3%). In a multivariable Cox model, ACR ( p<0.0001) and diabetes status ( p=0.01) were associated with adverse outcome even when several other clinical variables were included in the model. Furthermore, a negative interaction was found between diabetes and ACR ( p=0.01).

CONCLUSIONS/INTERPRETATION

Microalbuminuria frequently occurs in diabetic and non-diabetic AMI patients during the first 3 days of admission to hospital and can be used to identify subjects at high risk of mortality.

Comparison of the extent and severity of coronary artery disease in patients with acute myocardial infarction with and without microalbuminuria

The extent and severity of coronary atherosclerosis were compared between 43 microalbuminuric and 87 normoalbuminuric nondiabetic patients with acute myocardial infarction. Patients with microalbuminuria had significantly greater scores of the severity (Gensini score) and extent (Hamsten score) of coronary artery disease (p <0.001).

Relation of urinary albumin excretion to coronary heart disease and low renal function: Role of blood pressure

BACKGROUND

Previous studies report that urinary albumin excretion is associated with coronary heart disease (CHD). The present epidemiologic study investigated if (1) blood pressure status affects the association of urinary albumin excretion with CHD; and (2) urinary albumin excretion is associated with low renal function also.

METHODS

The cross-sectional association was analyzed of overnight urinary albumin excretion with prevalence of CHD (myocardial infarction and/or ischemia as defined by standard electrocardiogram) and low renal function (overnight creatinine clearance <60 mL/min) in a population sample of 1632 men and women with ages 45 to 64 years. Hypertension, hypercholesterolemia, smoking habit, and diabetes mellitus were included in analyses.

RESULTS

CHD prevalence was in the whole sample 8.2% (N= 134), in the hypertensive subgroup 11.9% (N= 79), and in the nonhypertensive subgroup 5.7% (N= 55). For the association between urinary albumin excretion (logarithm-transformed due to skewed distribution) and CHD, the multivariate logistic coefficient with 95% CI was significant in the whole sample (+0.79, 95% CI =+0.32/+1.26, P < 0.001) and in the hypertensive subgroup (+0.97, 95% CI =+0.70/+1.24, P < 0.001), not in the nonhypertensive subgroup (-0.06, 95% CI =-0.80/+0.68, P= 0.997). Prevalence of low creatinine clearance was in the whole sample 4.0% (N= 66), in the hypertensive subgroup 4.8% (N= 32), and in the nonhypertensive subgroup 3.5% (N= 34). The logistic coefficient between urinary albumin excretion and low creatinine clearance was borderline significant in the whole sample (+0.56, 95% CI =-0.02/+1.14, P= 0.090), significant in the hypertensive subgroup (+0.73, 95% CI =+0.04/+1.42, P= 0.044), not significant in the nonhypertensive subgroup (-0.07, 95% CI =-1.25/+1.10, P= 0.913).

CONCLUSION

Results support the use of urinary albumin excretion as marker of CHD and slightly reduced renal function in hypertensives.

Regression of albuminuria: latest evidence for a new approach

OBJECTIVE

To review the latest studies on antihypertensive strategies in the treatment of microalbuminuria, in order to highlight the association of microalbuminuria with hypertension and type 2 diabetes, the evidence for microalbuminuria as a risk factor for target-organ damage and mortality, and the prognostic significance of regression of microalbuminuria.

STUDY SELECTION

Randomized controlled trials in patients with hypertension, type 2 (non-insulin-dependent) diabetes mellitus and microalbuminuria, with changes in albumin excretion rate (AER) as a primary outcome measure.

RESULTS OF DATA ANALYSIS

Antihypertensive treatment is the most effective method for reducing microalbuminuria. Although microalbuminuria regression is related to reduction in blood pressure, antihypertensive drugs acting on the renin-angiotensin system have an antiproteinuric effect that is additional to that of blood pressure reduction. The combination of these agents with diuretics, even when used in low doses, may further reduce AER in these patients.

CONCLUSIONS

Blockade of the renin-angiotensin system with angiotensin-converting enzyme inhibitors or angiotensin receptor blockers is a most effective means of treating microalbuminuria and preventing its progression to overt nephropathy and, perhaps, the associated cardiovascular disease. The effect of this strategy may be improved further with the use, as first-line treatment, of a combination of angiotensin-converting enzyme inhibitor and diuretic.