Urinary peptide analysis to predict the response to blood pressure medication

BACKGROUND

The risk of diabetic kidney disease (DKD) progression is significant despite treatment with renin-angiotensin system (RAS) blocking agents. Current clinical tools cannot predict whether or not patients will respond to treatment with RAS inhibitors (RASi). We aimed to investigate whether proteome analysis could identify urinary peptides as biomarkers that could predict the response to angiotensin-converting enzyme inhibitor and angiotensin-receptor blockers treatment to avoid DKD progression. Furthermore, we investigated the comparability of the estimated glomerular filtration rate (eGFR), calculated using four different GFR equations, for DKD progression.

METHODS

We evaluated urine samples from a discovery cohort of 199 diabetic patients treated with RASi. DKD progression was defined based on eGFR percentage slope results between visits (∼1 year) and for the entire period (∼3 years) based on the eGFR values of each GFR equation. Urine samples were analysed using capillary electrophoresis-coupled mass spectrometry. Statistical analysis was performed between the uncontrolled (patients who did not respond to RASi treatment) and controlled kidney function groups (patients who responded to the RASi treatment). Peptides were combined in a support vector machine-based model. The area under the receiver operating characteristic curve was used to evaluate the risk prediction models in two independent validation cohorts treated with RASi.

RESULTS

The classification of patients into uncontrolled and controlled kidney function varies depending on the GFR equation used, despite the same sample set. We identified 227 peptides showing nominal significant difference and consistent fold changes between uncontrolled and controlled patients in at least three methods of eGFR calculation. These included fragments of collagens, alpha-1-antitrypsin, antithrombin-III, CD99 antigen and uromodulin. A model based on 189 of 227 peptides (DKDp189) showed a significant prediction of non-response to the treatment/DKD progression in two independent cohorts.

CONCLUSIONS

The DKDp189 model demonstrates potential as a predictive tool for guiding treatment with RASi in diabetic patients.

The Impact of Kidney Function on the Slow-Flow/No-Reflow Phenomenon in Patients Treated with Primary Percutaneous Coronary Intervention: Registry Analysis

OBJECTIVE

The objective of this study is to analyze the impact of declining kidney function on the occurrence of the slow-flow/no-reflow phenomenon in patients with ST-elevation myocardial infarction (STEMI) treated with primary PCI (pPCI), as well as the analysis of the prognostic impact of the slow-flow/no-reflow phenomenon on short- and long-term mortality in these patients.

METHODS

We analyzed 3,115 consecutive patients. A value of the glomerular filtration rate (eGFR) at the time of admission of eGFR <90 ml/min/m2 was considered a low baseline eGFR. The follow-up period was 8 years.

RESULTS

The slow-flow/no-reflow phenomenon through the IRA was registered in 146 (4.7%) patients. Estimated GFR of <90 ml/min/m2 was an independent predictor for the occurrence of the slow-flow/no-reflow phenomenon (OR 2.91, 95% CI 1.25-3.95, p < 0.001), and the risk for the occurrence of the slow-flow/no-reflow phenomenon increased with the decline of the kidney function: eGFR 60-89 ml/min/m2: OR 1.94 (95% CI 1.22-3.07, p = 0.005), eGFR 45-59 ml/min/m2: OR 2.55 (95% CI 1.55-4.94, p < 0.001), eGFR 30-44 ml/min/m2: OR 2.77 (95% CI 1.43-5.25, p < 0.001), eGFR 15-29 ml/min/m2: OR 5.84 (95% CI 2.84-8.01, p < 0.001). The slow-flow/no-reflow phenomenon was a strong independent predictor of short- and long-term all-cause mortality: 30-day mortality (HR 2.62, 95% CI 1.78-3.57, p < 0.001) and 8-year mortality (HR 2.09, 95% CI 1.49-2.09, p < 0.001).

CONCLUSION

Reduced baseline kidney function was an independent predictor for the occurrence of the slow-flow/no-reflow phenomenon, and its prognostic impact started with the mildest decrease in eGFR (below 90 ml/min/m2) and increased with its further decline. The slow-flow/no-reflow phenomenon was a strong independent predictor of mortality in the short- and long-term follow-up of the analyzed patients.

Impact of kidney function on the occurrence of new-onset atrial fibrillation in patients with ST-elevation myocardial infarction

OBJECTIVE

In this study, we aimed to examine the prognostic impact of decreased kidney function at admission on the occurrence of new-onset atrial fibrillation (AF) in patients with ST-elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (pPCI).

METHODS

The study enrolled 3,115 consecutive patients with STEMI. Kidney function was assessed by estimation of the glomerular filtration rate (eGFR) at admission. Patients with cardiogenic shock at admission, patients on hemodialysis, and patients with a medical history of previous AF (paroxysmal, persistent, or permanent) were excluded. The follow-up period was six years.

RESULTS

New-onset AF occurred in 215 (6.9%) patients, 75 (34.9%) patients presented with AF, and 140 (65.1%) patients developed AF after pPCI. The median time of AF occurrence in patients who did not present with AF was 4.5 (interquartile range 1-25) hours after pPCI. New-onset AF was associated with a higher short- and long-term mortality. In the multiple logistic regression analysis, all stages of reduced kidney function were independent predictors for the occurrence of new-onset AF, and negative prognostic impact increased with the deterioration of kidney function: eGFR <90 mL/min/m2, hazard ratio (HR) 1.96, 95% confidence interval (CI) 1.42-2.89, p=0.011; eGFR 60-89 mL/min/m2, HR 1.54, 95% CI 1.13-2.57, p=0.045; eGFR 45-59 mL/min/m2-, HR 2.09, 95% CI 1.24-2.85, p=0.023; eGFR 30-44 mL/min/m2-, HR 2.93, 95% CI 1.64-5.29, p<0.001; eGFR 15-29 mL/min/m2-, HR 5.51, 95% CI 2.67-11.39, p<0.001.

CONCLUSION

Decreased kidney function was significantly associated with the occurrence of new-onset AF, and its impact increased with the deterioration in kidney function, starting with an eGFR value of 90 mL/min/m2. New-onset AF was an independent predictor of long-term all-cause mortality in the analyzed patients.

Reassessment of kidney function equations in predicting long-term survival in cardiac surgery

BACKGROUND/OBJECTIVES

Chronic kidney disease (CKD) is a risk factor for long-term survival in cardiac surgery. The Cockcroft-Gault, Modification of Diet in Renal Disease (MDRD) study, CKD Epidemiology Collaboration (CKD-EPI), revised Lund-Malmö (LM), and full age spectrum equations are used to estimate glomerular filtration rates (eGFR), but each have advantages and disadvantages. Our objective was to determine which equation better predicts long-term survival.

METHODS

Data on 1492 consecutive patients who underwent isolated off-pump coronary artery bypass surgery between September 1996 and December 2008 were prospectively collected. Preoperative and postoperative eGFR were calculated using the five equations and compared using Cox regression analyses and time-dependent receiver operating characteristic (ROC) curves at 10 years.

RESULTS

In a Cox regression model after correction for significant predictors of long-term mortality, adjusted hazard ratios (HR) for one standard deviation increase in preoperative eGFR were 0.661 (P < .0001), 0.844 (P = .0166), 0.787 (P = .0002), 0.746 (P < .0001), and 0.717 (P < .0001) for the CG, MDRD, CKD-EPI, LM, and FAS equations, respectively. The areas under the time-dependent ROC curve at 10 years also showed that the CG formula has a better predictive value. Postoperative eGFR at discharge were also significant predictors of long-term mortality (HR = 0.603, P < .0001; HR = 0.725, P < .0001; HR = 0.688, P < .0001; HR = 0.673, P < .0001; HR = 0.632, P < .0001 for the CG, MDRD, CKD-EPI, LM, and FAS equations, respectively).

CONCLUSIONS

The CG formula was shown to better predict survival in cardiac surgery, though the FAS equation has a comparable prognostic value. Additionally, postoperative eGFR at discharge also predicted long-term survival.

Comparison of five glomerular filtration rate estimating equations as predictors of acute kidney injury after cardiovascular surgery

We aimed to compare the ability of preoperative estimated glomerular filtration rate (eGFR), calculated using five different equations, to predict adverse renal outcomes after cardiovascular surgery. Cohorts of 4,125 adult patients undergoing elective cardiovascular surgery were evaluated. Preoperative eGFR was calculated using the Cockcroft-Gault, Modification of Diet in Renal Disease (MDRD) II, re-expressed MDRD II, Chronic Kidney Disease Epidemiology Collaboration, and Mayo quadratic (Mayo) equations. The primary outcome was postoperative acute kidney injury (AKI), defined by Kidney Disease: Improving Global Outcomes Definition and Staging criteria based on changes in serum creatinine concentrations within 7 days. The MDRD II and Cockcroft-Gault equations yielded the highest (88.1 ± 26.7 ml/min/1.73 m2) and lowest (79.6 ± 25.5 ml/min/1.73 m2) mean eGFR values, respectively. Multivariable analysis showed that a preoperative decrease in renal function according to all five equations was independently associated with an increased risk of postoperative AKI. The area under the receiver operating characteristics curve for predicting postoperative AKI was highest for the Mayo equation (0.713). Net improvements in reclassification and integrated discrimination were higher for the Mayo equation than for the other equations. The Mayo equation was the most accurate in predicting postoperative AKI in patients undergoing cardiovascular surgery.

Prognostic impact of renal dysfunction on long-term mortality in patients with preserved, moderately impaired, and severely impaired left ventricular systolic function following myocardial infarction

Objective:

The aim of this study was to investigate and compare the prognostic impact of renal dysfunction (RD) at admission in patients with preserved, moderately impaired and severely impaired left ventricular systolic function following ST-elevation myocardial infarction (STEMI).

Methods:

We included 2436 patients with STEMI treated with primary percutaneous coronary intervention (pPCI). Patients presenting with cardiogenic shock and those on hemodyalisis were excluded. According to the left ventricular ejection fraction (EF), patients were divided in three groups: preserved left ventricular systolic function – EF >50%, moderately impaired – EF=40%-50% and severely impaired left ventricular systolic function-EF <40%. RD was defined as estimated glomerular filtration rate (eGFR) <60 mL/min/1.73m² at admission. The follow-up period was 6 years.

Results:

Preserved, moderately impaired and severely impaired systolic function were found in 741 (30.5%), 1367 (56.1%) and 328 (13.4%) patients, respectively. RD was present in 105 (14.2%) patients with preserved systolic function, 247 (18.1%) patients with moderately impaired, and 120 (36.5%) patients with severely impaired systolic function.Regardless of the presence of RD, 6-year mortality rates in patients with preserved, moderately impaired, and severely impaired systolic function were 2.7%, 5.2% and 31.1% respectively. Within each LVEF group, patients with RD had a worse outcome, both in the short- and long-term. In the Mulivariate Cox Analysis, RD remained an independent predictor of 6-year mortality in patients with moderately (HR 2.52, 95% CI 1.54-3.78) and severely impaired systolic function (HR 2.84, 95% CI 1.68-5.34), but not in patients with preserved left ventricular systolic function (HR 0.59, 95% CI 0.14-1.41).

Conclusion:

Although patients with RD had higher 6-year mortallity following STEMI regardless of LVEF, RD at admission remained a strong independent predictor for 6-year mortality only in patients with moderately and severely impaired left ventricular systolic function.

The Impact of Admission Serum Creatinine Derived Estimated Glomerular Filtration Rate on Major Adverse Cardiac Events in ST-Segment Elevation Myocardial Infarction Patients Undergoing Primary Percutaneous Coronary Intervention

Background

The impact of Cockroft-Gault (C-G) derived estimated glomerular filtration rate (eGFR) on mortality and major adverse cardiac events (MACEs) in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI) was assessed.

Methods

A total of 884 patients were classified into four categories according to admission creatine derived eGFR: < 60, 60 - < 90, 90 - < 120, and ≥ 120 mL/min/1.73 m².

Results

In-hospital and long-term MACEs were significantly higher in eGFR < 60 mL/min/1.73 m² subgroup (P < 0.001 and P = 0.028). Multivariate analysis demonstrated 7.78-fold (95% CI: 0.91 - 66.8) higher mortality risk in eGFR < 60 mL/min/1.73 m² subgroup.

Conclusion

As an easily applicable bedside method, C-G derived eGFR could be important for prediction of in-hospital and long-term mortality and MACE in STEMI patients undergoing primary PCI.

Prevalence and severity of asymptomatic coronary and carotid artery disease in patients with abdominal aortic aneurysm

We evaluated the prevalence and severity of occult coronary artery disease (CAD) and cerebrovascular disease (CeVD) in patients with abdominal aortic aneurysm (AAA). We studied 100 consecutive patients with no history of CAD, normal electrocardiogram, normal systolic function, and no angina or dyspnea. All patients underwent carotid Doppler study and invasive coronary angiography. Significant CAD was observed in 61% of patients. In all, 51% of patients with significant CAD showed either left main (n = 7), 3-vessel (n = 17), or proximal left anterior descending (n = 7) CAD, corresponding to 31% of the total cohort. Cerebrovascular disease was detected in 53% of patients, and in 38% of them was significant (peak systolic flow velocity ≥125 <230 cm/s). In 36% of patients with CeVD either left main (n = 5), 3-vessel (n = 11), or proximal left anterior descending (n = 3) CAD was observed. Severe asymptomatic CAD is prevalent in AAA, and 31% of patients fulfill indications for coronary revascularization.