Albina Nowak

Effect and Clinical Prediction of Worsening Renal Function in Acute Decompensated Heart Failure

We aimed to establish the prevalence and effect of worsening renal function (WRF) on survival among patients with acute decompensated heart failure. Furthermore, we sought to establish a risk score for the prediction of WRF and externally validate the previously established Forman risk score. A total of 657 consecutive patients with acute decompensated heart failure presenting to the emergency department and undergoing serial creatinine measurements were enrolled. The potential of the clinical parameters at admission to predict WRF was assessed as the primary end point. The secondary end point was all-cause mortality at 360 days. Of the 657 patients, 136 (21%) developed WRF, and 220 patients had died during the first year. WRF was more common in the nonsurvivors (30% vs 41%, p = 0.03). Multivariate regression analysis found WRF to independently predict mortality (hazard ratio 1.92, p <0.01). In a single parameter model, previously diagnosed chronic kidney disease was the only independent predictor of WRF and achieved an area under the receiver operating characteristic curve of 0.60. After the inclusion of the blood gas analysis parameters into the model history of chronic kidney disease (hazard ratio 2.13, p = 0.03), outpatient diuretics (hazard ratio 5.75, p <0.01), and bicarbonate (hazard ratio 0.91, p <0.01) were all predictive of WRF. A risk score was developed using these predictors. On receiver operating characteristic curve analysis, the Forman and Basel prediction rules achieved an area under the curve of 0.65 and 0.71, respectively. In conclusion, WRF was common in patients with acute decompensated heart failure and was linked to significantly worse outcomes. However, the clinical parameters failed to adequately predict its occurrence, making a tailored therapy approach impossible.

Direct Comparison of Three Natriuretic Peptides for Prediction of Short- and Long-term Mortality in Patients With Community-Acquired Pneumonia

BACKGROUND Early and accurate risk stratification for patients with community-acquired pneumonia (CAP) is an unmet clinical need. METHODS We enrolled 341 unselected patients presenting to the ED with CAP in whom blinded measurements of N-terminal pro-B-type natriuretic peptide (NT-proBNP), midregional pro-atrial natriuretic peptide (MR-proANP), and B-type natriuretic peptide (BNP) were performed. The potential of these natriuretic peptides to predict short- (30-day) and long-term mortality was compared with the pneumonia severity index (PSI) and CURB-65 (confusion, urea plasma level, respiratory rate, BP, age over 65 years). The median follow-up was 942 days. RESULTS NT-proBNP, MR-proANP, and BNP levels at presentation were higher in short-term (median 4,882 pg/mL vs 1,133 pg/mL; 426 pmol/L vs 178 pmol/L; 436 pg/mL vs 155 pg/mL, all P < .001) and long-term nonsurvivors (3,515 pg/mL vs 548 pg/mL; 283 pmol/L vs 136 pmol/L; 318 pg/mL vs 103 pg/mL, all P < .001) as compared with survivors. Receiver operating characteristics analysis to quantify the prognostic accuracy showed comparable areas under the curve for the three natriuretic peptides to PSI for short-term (PSI 0.76, 95% CI, 0.71-0.81; NT-proBNP 0.73, 95% CI, 0.67-0.77; MR-proANP 0.72, 95% CI, 0.67-0.77; BNP 0.68, 95% CI, 0.63-0.73) and long-term (PSI 0.72, 95% CI, 0.66-0.77; NT-proBNP 0.75, 95% CI, 0.70-0.80; MR-proANP 0.73, 95% CI, 0.67-0.77, BNP 0.70, 95% CI, 0.65-0.75) mortality. In multivariable Cox-regression analysis, NT-proBNP remained an independent mortality predictor (hazard ratio 1.004, 95% CI, 1.00-1.01, P = .02 for short-term; hazard ratio 1.004, 95% CI, 1.00-1.01, P = .001 for long-term, increase of 300 pg/mL). A categorical approach combining PSI point values and NT-pro-BNP levels adequately identified patients at low, medium, and high short- and long-term mortality risk. CONCLUSIONS Natriuretic peptides are simple and powerful predictors of short- and long-term mortality for patients with CAP. Their prognostic accuracy is comparable to PSI.

Prognostic value and link to atrial fibrillation of soluble Klotho and FGF23 in hemodialysis patients.

Deranged calcium-phosphate metabolism contributes to the burden of morbidity and mortality in dialysis patients. This study aimed to assess the association of the phosphaturic hormone fibroblast growth factor 23 (FGF23) and soluble Klotho with all-cause mortality. We measured soluble Klotho and FGF23 levels at enrolment and two weeks later in 239 prevalent hemodialysis patients. The primary hypothesis was that low Klotho and high FGF23 are associated with increased mortality. The association between Klotho and atrial fibrillation (AF) at baseline was explored as secondary outcome. AF was defined as presence of paroxysmal, persistent or permanent AF. During a median follow-up of 924 days, 59 (25%) patients died from any cause. Lower Klotho levels were not associated with mortality in a multivariable adjusted analysis when examined either on a continuous scale (HR 1.25 per SD increase, 95% CI 0.84–1.86) or in tertiles, with tertile 1 as the reference category (HR for tertile two 0.65, 95% CI 0.26–1.64; HR for tertile three 2.18, 95% CI 0.91–2.23). Higher Klotho levels were associated with the absence of AF in a muItivariable logistic regression analysis (OR 0.66 per SD increase, 95% CI 0.41–1.00). Higher FGF23 levels were associated with mortality risk in a multivariable adjusted analysis when examined either on a continuous scale (HR 1.45 per SD increase, 95% CI 1.05–1.99) or in tertiles, with the tertile 1 as the reference category (HR for tertile two 1.63, 95% CI 0.64–4.14; HR for tertile three 3.91, 95% CI 1.28–12.20). FGF23 but not Klotho levels are associated with mortality in hemodialysis patients. Klotho may be protective against AF.

Mortality Prediction Using Modern Peptide Biomarkers in Hemodialysis Patients - A Comparative Analysis

Background/Aims: Determination of peptide biomarkers such as troponins, natriuretic peptides or the recently reported FGF23 can be useful to identify hemodialysis patients with a high risk of mortality. However, it is desirable to focus on few robust parameters to warrant their routine application. Methods: In a prospective cohort study with 239 prevalent hemodialysis patients we studied the prognostic significance of 10 simultaneously determined modern peptide biomarkers (high sensitive troponin I and T, NT-pro-BNP, BNP, MR-pro-ANP, MR-pro-ADM, CT-pro-ET1, copeptin, FGF23 and a-Klotho) and compared them with parameters traditionally associated with mortality (PTH, Ca, Pi, albumin, CRP, cholesterol, AP). Results: After a follow-up of 4 years, plasma concentration of troponins, natriuretic peptides, MR-pro-ADM, FGF23 as well as PTH, CRP, AP were significantly higher in deceased patients (n=95). Hazard ratios from cox regression on a continuous scale (doubling of plasma concentration) or relative in tertiles were highest for high sensitive troponins, followed by natriuretic peptides and MR-pro-ADM (1.6-2.0 and 2.3-5.5, resp.). C-indices were also highest for troponins (0.708-0.746), followed by natriuretic peptides (0.706-0.731). Traditional parameters had low c-indices (0.598-0.655). Stepwise cox regression revealed that among all parameters troponin I, NT-pro-BNP, PTH and CRP remained independent predictors of mortality and a composite score had the highest c-index (0.799 [0.740-0.849]). Conclusions: Among peptide biomarkers high sensitive troponins and to a lesser extent natriuretic peptides are strong predictors of mortality in asymptomatic hemodialysis patients, followed by markers of mineral-bone disease and inflammation.

Plasma LysoGb3: A useful biomarker for the diagnosis and treatment of Fabry disease heterozygotes

BACKGROUND Fabry disease (FD) is a rare X-linked lysosomal storage disorder due to mutations in the α-galactosidase A gene (GLA) that result in absent or markedly reduce α-galactosidase A (α-GalA) enzymatic activity. As a result, the major glycosphingolipid substrates, globotriaosylceramide (Gb3) and globotriaosylsphingosine (LysoGb3) accumulate in plasma, urine and tissue lysosomes. In females, the diagnosis can be complicated by the fact that 40-50% of GLA-mutation confirmed heterozygotes have normal or only slightly decreased leukocyte α-GalA activities. Recently, LysoGb3 has been appreciated as a novel FD biomarker, especially for therapeutic monitoring. METHODS Among our GLA-mutation proven FD patients, we screened 18 heterozygotes whose leukocyte α-GalA activity was determined at initial diagnosis. For these females, we measured their serum LysoGb3 levels using highly-sensitive electrospray ionization liquid chromatography tandem mass spectrometry. RESULTS We identified three unrelated females in whom the accumulating LysoGb3 was increased, whereas their leukocyte α-GalA activities were in the normal range. CONCLUSION LysoGb3 serves as an useful biomarker to improve the diagnosis of FD heterozygotes and for therapeutic evaluation and monitoring.

Prediction of mortality using quantification of renal function in acute heart failure

BACKGROUND Renal function, as quantified by the estimated glomerular filtration rate (eGFR), is a predictor of death in acute heart failure (AHF). It is unknown whether one of the clinically-available serum creatinine-based formulas to calculate eGFR is superior to the others for predicting mortality. METHODS AND RESULTS We quantified renal function using five different formulas (Cockroft-Gault, MDRD-4, MDRD-6, CKD-EPI in patients<70 years, and BIS-1 in patients≥70 years) in 1104 unselected AHF patients presenting to the emergency department and enrolled in a multicenter study. Two independent cardiologists adjudicated the diagnosis of AHF. The primary endpoint was the accuracy of the five eGFR equations to predict death as quantified by the time-dependent area under the receiver-operating characteristics curve (AUC). The secondary endpoint was the accuracy to predict all-cause readmissions and readmissions due to AHF. In a median follow-up of 374 days (IQR: 221 to 687 days), 445 patients (40.3%) died. eGFR as calculated by all equations was an independent predictor of mortality. The Cockcroft-Gault formula showed the highest prognostic accuracy (AUC 0.70 versus 0.65 for MDRD-4, 0.55 for MDRD-6, and 0.67 for the combined formula CKD-EPI/BIS-1, p<0.05). These findings were confirmed in patients with varying degrees of renal function and in three vulnerable subgroups: women, patients with severe left ventricular dysfunction, and the elderly. The prognostic accuracy for readmission was poor for all equations, with an AUC around 0.5. CONCLUSIONS Calculating eGFR using the Cockcroft-Gault formula assesses the risk of mortality in patients with AHF more accurately than other commonly used formulas.

Natriuretic peptides for early prediction of acute kidney injury in community-acquired pneumonia

BACKGROUND Community-acquired pneumonia (CAP) is common and associated with a considerable risk of acute kidney injury (AKI). METHODS We prospectively enrolled 341 patients presenting to the emergency department with CAP (mean age 72, male 61%). Blinded measurements of three natriuretic peptides (NT-proBNP, MR-proANP and BNP) were performed upon presentation. The primary endpoint was the accuracy of the natriuretic peptides to predict AKI within 48h. RESULTS AKI occurred in 24 patients (7.6%) within the first 48h. NPs and creatinine were significantly higher in AKI compared with patients without AKI (NT-proBNP 9517 [2042-26,792] vs 1177 [280-4167]pg/ml; MR-proANP 641 [196-1075] vs 182 [99-352]pmol/l; BNP 592 [230-1630] vs 160 [64-463]pg/ml; creatinine 166 [131-289] versus 100 [78-134] μmol/l, P<0.001 for each). Predictive accuracy as quantified by the area under the receiver operating characteristics curve was moderate to high: NT-proBNP 0.79 (95%CI 0.70-0.88), MR-proANP 0.78 (95%CI 0.67-0.88), BNP 0.74 (95%CI 0.63-0.85), creatinine 0.77 (95%CI 0.66-0.88). In multivariate logistic regression analysis, NPs remained the only independent AKI predictors: NT-proBNP (increase of 200 pg/ml) OR=1.01, 95%CI 1.00-1.01, P=0.009; MR-proANP (increase of 100 pg/ml) OR=1.23, 95%CI 1.09-1.39, P=0.001; BNP (increase of 100 pg/ml) OR=1.08, 95%CI 1.03-1.14, P=0.002. CONCLUSIONS NP levels are significantly elevated in CAP-patients experiencing early AKI. Their potential to predict early AKI is comparable to serum creatinine and might be useful in cases of diagnostic uncertainty.

Plasma concentrations of the vasoactive peptide fragments mid-regional pro-adrenomedullin, C-terminal pro-endothelin 1 and copeptin in hemodialysis patients: associated factors and prediction of mortality

Vasopressin, endothelin and adrenomedullin are vasoactive peptides that regulate vascular tone and might play a role in hypertensive diseases. Recently, laboratory assays have been developed to measure stable fragments of vasopressin, endothelin and adrenomedullin. Little is known about their diagnostic and prognostic value in hemodialysis patients. In this study, we measured the plasma concentration of copeptin, mid-regional-pro-adrenomedullin (MR-pro-ADM) and C-terminal pro-endothelin 1 (CT-pro-ET1) in stable ambulatory hemodialysis patients (n = 239) and investigated their associations with clinical factors and mortality. In all patients enrolled, the plasma concentrations of copeptin, MR-pro-ADM and CT-pro-ET1 were largely elevated with a median concentration of 132 pmol/L (interquartile range [IQR] 78–192) for copeptin, 1.26 nmol/L (IQR 1.02–1.80) for MR-pro-ADM and 149 pmol/L (IQR 121–181) for CT-pro-ET1. The plasma concentrations of all vasoactive peptide fragments correlated with time on dialysis and plasma β2-microglobulin concentration and were negatively correlated to residual diuresis. The plasma concentration of MR-pro-ADM was a strong predictor of all-cause (univariate hazard ratio for a 10-fold increase 9.94 [3.14;32], p<0.0001) and cardiovascular mortality (hazard ratio 34.87 [5.58;217], p = 0.0001) within a 3.8-year follow-up. The associations remained stable in models adjusted for dialysis specific factors and were attenuated in a full model adjusted for all prognostic factors. Plasma copeptin concentration was weakly associated with cardiovascular mortality (only in univariate analysis) and CT-pro-ET1 was not associated with mortality at all. In conclusion, vasoactive peptide fragments are elevated in hemodialysis patients because of accumulation and, most likely, increased release. Increased concentrations of MR-pro-ADM are predictive of mortality.

The value of ECG parameters as markers of treatment response in Fabry cardiomyopathy

Objective Best treatment outcomes in Fabry disease (FD) associated cardiomyopathy can be obtained when treatment is started as early as possible. The rationale of this study was to assess the role of ECG changes for identification of cardiac involvement and patients at an earlier stage of the disease more likely deriving a benefit from enzyme replacement therapy (ERT). Methods A retrospective analysis of patient data was performed from an observational, longitudinal, prospective cohort. Treatment response was defined as absence or presence of disease progression, defined as new onset or increase in left ventricular (LV) mass >10%. Demographic, clinical, ECG and echocardiographic parameters at baseline were tested for their value in determining absence or presence of disease progression under ERT at 5-year follow-up. Results The study population consisted of a total of 38 patients (25 men, mean age 36±13 years, overall median follow-up duration 6.4±1.2 years). Patients in the progression group (14 men, 4 women) had a longer QRS duration (99±11 ms vs 84±13 ms, p<0.05 for men, 93±9 years vs 81±5 years, p<0.05 for women) and QTc interval (401±15 ms vs 372±10 ms, p<0.005 for men) and a higher amount of ECG abnormalities (86% vs 18%, p<0.005 for men and 100% vs 0%, p<0.005 for women) at the time of ERT initiation. An abnormal baseline ECG was significantly associated with disease progression (sensitivity 94.1%, specificity 88.9%, positive likelihood ratio of 8.47, p<0.005). Conclusions An abnormal ECG at the time of treatment initiation is significantly associated with cardiac disease progression in FD. This effect seems to be independent of age, gender or LV mass at baseline and suggests maximal treatment benefit when ERT is initiated before ECG abnormalities develop.

Sclerostin Quo Vadis? - Is This a Useful Long-Term Mortality Parameter in Prevalent Hemodialysis Patients?

Background/Aims: Cardiovascular calcification contributes to the increased mortality in hemodialysis patients. Sclerostin was identified as an antianabolic bone factor causing soft tissue calcification. Data on prospective large-scale studies associating sclerostin with mortality in hemodialysis patients are so far inconsistent. Methods: In our multicenter prospective longitudinal study following hemodialysis patients, we assessed the associations of sclerostin and bone remodeling markers with long-term mortality. We evaluated the relationship between circulating sclerostin, Fibroblast growth factor 23 (FGF23) and traditional bone remodeling markers. Sclerostin levels in hemodialysis patients were compared with healthy controls. Results: We enrolled 239 hemodialysis patients with a median follow up of 1461 days. In Cox regression analysis, FGF23 (HR 1.40;95%CI 1.11-1.76), parathyroid hormone (PTH) (HR 1.80;95%CI 1.44-2.26) and alkaline phosphatase (AP) (HR 1.50;95%CI 1.10-2.04) per SD, 25(OH)vitamin D (HR 0.42;95%CI 0.23-0.76) per natural log but not sclerostin (HR 1.02;95%CI 0.75-1.38) per SD increase were associated with mortality. FGF23, PTH and AP were negatively associated with sclerostin. Among control and hemodialysis females, sclerostin levels were lower than in men. Conclusion: Higher FGF23, PTH, AP and lower 25(OH)vitamin D but not sclerostin predict long-term mortality. Sclerostin was negatively associated with FGF23, PTH and AP and lower in females than in males.