Targeting N-Terminal Pro-Brain Natriuretic Peptide in Older Versus Younger Acute Decompensated Heart Failure Patients.

OBJECTIVES: The aim of this study was to analyze the prognostic value and attainability of N-terminal pro-brain natriuretic peptide (NT-proBNP) levels in young and elderly acute decompensated heart failure (ADHF) patients. BACKGROUND: Less-effective NT-proBNP-guided therapy in chronic heart failure (HF) has been reported in elderly patients. Whether this can be attributed to differences in prognostic value of NT-proBNP or to differences in attaining a prognostic value is unclear. The authors studied this question in ADHF patients. METHODS: Our study population comprised 7 ADHF cohorts. We defined absolute (<1,500 ng/l, <3,000 ng/l, <5,000 ng/l, and <15,000 ng/l) and relative NT-proBNP discharge cut-off levels (>30%, >50%, and >70%). Six-month all-cause mortality after discharge was studied for each level in Cox regression analyses, and compared between elderly (age >75 years) and young patients (age ≤75 years). Thereafter, we compared percentages of elderly and young patients attaining NT-proBNP levels (= attainability). RESULTS: A total of 1,235 patients (59% male, 45% >75 years of age) was studied. Admission levels of NT-proBNP were significantly higher in elderly versus younger patients. The prognostic value of absolute and relative NT-proBNP levels was similar in elderly and young patients. Attainability was significantly lower in elderly patients for all absolute levels and a >50% relative reduction, but not for >30% and >70%. For absolute levels, attainability differences between age groups were decreased to a large extent after correction for admission NT-proBNP and anemia at discharge. For relative levels, attainability differences disappeared after correction for HF etiology and anemia at discharge. CONCLUSIONS: In young and elderly ADHF patients, it is not the prognostic value of absolute and relative NT-proBNP levels that is different, but the attainability of these levels that is lower in the elderly. This can largely be attributed to factors other than age.

Competing Risk of Cardiac Status and Renal Function During Hospitalization for Acute Decompensated Heart Failure.

OBJECTIVES: The aim of this study was to analyze the dynamic changes in renal function in combination with dynamic changes in N-terminal pro-B-type natriuretic peptide (NT-proBNP) in patients hospitalized for acute decompensated heart failure (ADHF). BACKGROUND: Treatment of ADHF improves cardiac parameters, as reflected by lower levels of NT-proBNP. However this often comes at the cost of worsening renal parameters (e.g., serum creatinine, estimated glomerular filtration rate [eGFR], or serum urea). Both the cardiac and renal markers are validated indicators of prognosis, but it is not yet clear whether the benefits of lowering NT-proBNP are outweighed by the concomitant worsening of renal parameters. METHODS: This study was an individual patient data analysis assembled from 6 prospective cohorts consisting of 1,232 patients hospitalized for ADHF. Endpoints were all-cause mortality and the composite of all-cause mortality and/or readmission for a cardiovascular reason within 180 days after discharge. RESULTS: A significant reduction in NT-proBNP was not associated with worsening of renal function (WRF) or severe WRF (sWRF). A reduction of NT-proBNP of more than 30% during hospitalization determined prognosis (all-cause mortality hazard ratio [HR]: 1.81; 95% confidence Interval [CI]: 1.32 to 2.50; composite endpoint: HR: 1.36, 95% CI: 1.13 to 1.64), regardless of changes in renal function and other clinical variables. CONCLUSIONS: When we defined prognosis, NT-proBNP changes during hospitalization for treatment of ADHF prevailed over parameters for worsening renal function. Severe WRF is a measure of prognosis, but is of lesser value than, and independent of the prognostic changes induced by adequate NT-proBNP reduction. This suggests that in ADHF patients it may be warranted to strive for an optimal decrease in NT-proBNP, even if this induces WRF.

Challenging the two concepts in determining the appropriate pre-discharge N-terminal pro-brain natriuretic peptide treatment target in acute decompensated heart failure patients: absolute or relative discharge levels?

AIMS: NT-proBNP is a strong predictor for readmissions and mortality in acute decompensated heart failure (ADHF) patients. We assessed whether absolute or relative NT-proBNP levels should be used as pre discharge treatment target. METHODS AND RESULTS: Our study population was assembled from seven ADHF cohorts. We defined absolute (<1500, <3000, <5000, and <15 000 ng/L) and relative NT-proBNP targets (>30, >50, and >70%). Population attributable risk fraction (PARF) is the proportion of all-cause 6-month mortality in the population that would be reduced if all patients attain the NT-proBNP target. PARF was determined for each target as well as the percentage of patients attaining the NT-proBNP target. Attainability was investigated by logistic regression analysis. A total of 1266 patients [age 74 (64-80), 60% male] was studied. For every absolute NT-proBNP level, a corresponding percentage reduction was found that resulted in similar PARFs. The highest PARF (∼60-70%) was observed for <1500 or >70%, but attainability was low (27% and 22%, respectively). The strongest predictor for not attaining these targets was admission NT-proBNP. In admission NT-proBNP tertiles, PARFs were significantly different for absolute, but not for relative targets. CONCLUSION: In an ADHF population, pre-discharge absolute or relative NT-proBNP targets may both be useful as they have similar effects on PARF. However, depending on admission NT-proBNP, absolute targets show varying PARFs, while PARFs for relative targets were similar. A relative target is predicted to reduce mortality consistently across the whole spectrum of ADHF patients, while this is not the case using a single absolute target.

A novel discharge risk model for patients hospitalised for acute decompensated heart failure incorporating N-terminal pro-B-type natriuretic peptide levels: a European coLlaboration on Acute decompeNsated Heart Failure: ELAN-HF Score.

BACKGROUND: Models to stratify risk for patients hospitalised for acute decompensated heart failure (ADHF) do not include the change in N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels during hospitalisation. OBJECTIVE: The aim of our study was to develop a simple yet robust discharge prognostication score including NT-proBNP for this notorious high-risk population. DESIGN: Individual patient data meta-analyses of prospective cohort studies. SETTING: Seven prospective cohorts with in total 1301 patients. PATIENTS: Our study population was assembled from the seven studies by selecting those patients admitted because of clinically validated ADHF, discharged alive, and NT-proBNP measurements available at admission and at discharge. MAIN OUTCOME MEASURES: The endpoints studied were all-cause mortality and a composite of all-cause mortality and/or first readmission for cardiovascular reason within 180 days after discharge. RESULTS: The model that incorporated NT-proBNP levels at discharge as well as the changes in NT-proBNP during hospitalisation in addition to age ≥75 years, peripheral oedema, systolic blood pressure ≤115 mm Hg, hyponatremia at admission, serum urea of ≥15 mmol/L and New York Heart Association (NYHA) class at discharge, yielded the best C-statistic (area under the curve, 0.78, 95% CI 0.74 to 0.82). The addition of NT-proBNP to a reference model significantly improved prediction of mortality as shown by the net reclassification improvement (62%, p<0.001). A simplified model was obtained from the final Cox regression model by assigning weights to individual risk markers proportional to their relative risks. The risk score we designed identified four clinically significant subgroups. The pattern of increasing event rates with increasing score was confirmed in the validation group (BOT-AcuteHF, n=325, p<0.001). CONCLUSIONS: In patients hospitalised for ADHF, the addition of the discharge NT-proBNP values as well as the change in NT-proBNP to known risk markers, generates a relatively simple yet robust discharge risk score that importantly improves the prediction of adverse events.