Natriuretic Peptide Testing in Clinical Medicine

N-Terminal Prohormone Brain Natriuretic Peptide as a Prognostic Biomarker for the Risk of Complications in Type 2 Diabetes: A Systematic Review and Meta-Analysis

Objective

This systematic review and meta-analysis aimed at summarizing the existing clinical evidence to evaluate the prognostic performance of N-terminal prohormone brain natriuretic peptide (NT-proBNP) in predicting cardiovascular events, cardiovascular-related mortality, and all-cause mortality in patients with type 2 diabetes.

Methods

Searches were performed in Medline, Embase, Scopus, and Web of Science databases before August 1, 2021. The data were recorded as adjusted hazard ratio (HR).

Results

An increase in NT-proBNP increases the risk of cardiovascular events (HR = 1.63), cardiovascular mortality (HR = 1.86) and all-cause mortality (HR = 1.54). Seemingly, the best cutoffs for predicting cardiovascular events (HR = 2.30) and cardiovascular mortality (HR = 3.77) are levels greater than 100 pg/mL. The best cutoff of NT-proBNP in predicting all-cause mortality is levels greater than 225 pg/mL (HR = 4.72).

Conclusion

A moderate level of evidence demonstrated that NT-proBNP serum levels can predict future cardiovascular events, cardiovascular mortality, and all-cause mortality. Thus, it can be used as risk stratification for type 2 diabetes.

Serum Levels of Cardiac Markers NT-proANP and NT-proBNP in Brachycephalic bitches at Different Gestational Stages

The aim of this study was to determine serum levels of natriuretic peptide precursors (NT-proANP and NT-proBNP) during pregnancy in brachycephalic bitches. Fifteen healthy multiparous bitches were selected for this prospective study. Serum levels of NT-proANP and NT-proBNP were measured during anoestrous and at 14, 35, 42, 49 and 56 days (2nd, 5th, 6th, 7th and 8th weeks) of pregnancy. Fourteen animals had normal gestations, and one bitch developed single foetus syndrome. The natriuretic peptide levels of this animal were not included in this study; however, it is important to report that its NT-proANP levels were four times greater than those of normal patients. There was no significant difference (p = 0.072) in NT-proBNP levels between anoestrous (0.20 ± 0.10 ng/ml) and the different pregnancy weeks (0.27 ± 0.12 ng/ml). There was a positive correlation (p < 0.0001) between NT-proANP and gestational age, and the levels of this marker increased significantly (p < 0.0001) during the 6th (0.26 ± 0.06 ng/ml), 7th (0.28 ± 0.04 ng/ml) and 8th weeks (0.29 ± 0.05 ng/ml) when compared to anoestrous (0.18 ± 0.02 ng/ml). NT-proANP serum levels are correlated with gestational development and may be indicative of cardiovascular adaptation in canine brachycephalic pregnancy.

Using ST2 in cardiovascular patients: a review

Biomarkers have emerged as indispensable tools for diagnosis and prognostication in a variety of cardiovascular diseases, and several are now standard of care. New markers are constantly being developed, but few are able to significantly improve upon already established markers. ST2 is a marker of cardiomyocyte stress and fibrosis, which provides incremental value to natriuretic peptides for risk stratification of patients across a wide spectrum of cardiovascular diseases. Based upon the totality of data, measurement of ST2 is now recommended for additive risk stratification in patients with acute or ambulatory heart failure in the 2013 American College of Cardiology Foundation and American Heart Association joint guidelines. Looking forward, ST2 levels may be useful for tailoring medical therapy in those with or at risk for developing heart failure. This paper provides an up-to-date overview of the clinical studies that led to the endorsement of ST2 as a cardiovascular prognostic marker, and provides insight into the application of ST2 now and in the future.

Evolution of biomarker guided therapy for heart failure: current concepts and trial evidence

Optimizing management of patients with heart failure remains quite challenging despite many significant advances in drug and device therapy for this syndrome. Although a large body of evidence from robust clinical trials supports multiple thera-pies, utilization of these well-established treatments remains inconsistent and outcomes suboptimal in “real-world” patients with heart failure. Disease management programs may be effective, but are difficult to implement due to cost and logistical issues. Another approach to optimizing therapy is to utilize biomarkers to guide therapeutic choices. Natriuretic peptides pro-vide additional information of significant clinical value in the diagnosis and estimation of risk inpatients with heart failure. Ongoing research suggests a potential important added role for natriuretic peptides in heart failure. Guiding therapy based on serial changes in these biomarkers may be an effective strategy to optimize treatment and achieve better outcomes in this syn-drome. Initial, innovative, proof-of-concept studies have provided encouraging results and important insights into key as-pects of this strategy, but well designed, large-scale, multicenter, randomized, outcome trials are needed to definitively estab-lish this novel approach to management. Given the immense and growing public health burden of heart failure, identification of cost-effective ways to decrease the morbidity and mortality due to this syndrome is critical.

Cautious application of pleural N-terminal pro-B-type natriuretic peptide in diagnosis of congestive heart failure pleural effusions among critically ill patients

Background and Objective

Several studies on diagnostic accuracy of pleural N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) for effusions from congestive heart failure (CHF) conclude that pleural NT-pro-BNP is a useful biomarker with high diagnostic accuracy for distinguishing CHF effusions. However, its applicability in critical care settings remains uncertain and requires further investigations.

Methods

NT-proBNP was measured in pleural fluid samples of a prospective cohort of intensive care unit patients with pleural effusions. Receiver operating characteristic curve analysis was performed to determine diagnostic accuracy of pleural NT-proBNP for prediction of CHF effusions.

Results

One hundred forty-seven critically ill patients were evaluated, 38 (26%) with CHF effusions and 109 (74%) with non-CHF effusions of various causes. Pleural NT-proBNP levels were significantly elevated in patients with CHF effusions. Pleural NT-pro-BNP demonstrated the area under the curve of 0.87 for diagnosing effusions due to CHF. With a cutoff of 2200 pg/mL, pleural NT-proBNP displayed high sensitivity (89%) but moderate specificity (73%). Notably, 29 (27%) of 109 patients with non-CHF effusions had pleural NT-proBNP levels >2200 pg/mL and these patients were more likely to experience septic shock (18/29 vs. 10/80, P<0.001) or acute kidney injury (19/29 vs. 9/80, P<0.001).

Conclusions

Among critically ill patients, pleural NT-proBNP measurements remain a useful diagnostic aid in evaluation of pleural effusions. However, patients with non-CHF effusions may exhibit high pleural NT-proBNP concentrations if they suffer from septic shock or acute kidney injury. Accordingly, it is suggested that clinical context should be taken into account when interpreting pleural NT-proBNP values in critical care settings.

ProANP plasma measurement predicts all-cause mortality in acutely hospitalised patients: a cohort study

IMPORTANCE

The association of natriuretic peptide measurement with all-cause mortality in a broad selection of acutely admitted patients has not yet been examined.

OBJECTIVE

To test the risk association between pro-atrial natriuretic peptide (ANP) and short-term and long-term mortality and its predictive value in acutely hospitalised patients and compare this to N-terminal B-type natriuretic peptide (NT-proBNP).

DESIGN, SETTING AND PATIENTS

Participants were selected from the Copenhagen Hospital Heart Failure Study (n=3644). Medical history, satisfactory echocardiography and blood samples were available on 2193 participants in 1998-1999 where NT-proBNP was measured. Vital status after discharge was obtained from national central data registers. A total of 1337 participants with eligible blood samples were selected in 2010-2011 for proANP measurement. Among these, 1255 (94%) were acutely hospitalised in 1998-1999.

MAIN OUTCOME MEASURE(S)

1-year and long-term mortality.

RESULTS

Median follow-up period was 11.5 years. At the end of follow-up, 926 patients had died, 239 during the first year. ProANP quartiles to 2-4 (median proANP levels 594 pmol/L, 990 pmol/L and 2052 pmol/L, respectively) associated with a stepwise increase in risk of 1-year and long-term mortality compared to the first quartile (336 pmol/L) in multivariable adjusted Cox proportional regression models (HR 1.53 95% CI 1.30 to 1.81 and HR 1.26 95% CI 1.17 to 1.36, respectively). An addition of NT-proBNP attenuated proANP's association with mortality in the models (HR 1.24 95% CI 1.01 to 1.53 and 1.14 95% CI 1.03 to 1.26, respectively). The increased risk was observed in participants with the highest proANP levels (fourth quartile). Similar results were observed in subgroups of participants with no evidence of cardiovascular disease (CVD). ProANP in quartiles improved discrimination when added to traditional risk factors in prediction models for 1-year (integrated discrimination improvement (IDI) 0.141 95% CI 0.085 to 0.197; C-index 0.753 95% CI 0.724 to 0.783, P for improvement 0.003) and long-term mortality (IDI 0.053 95% CI 0.032 to 0.074; C-index 0.736 95% CI 0.720 to 0.752, P for improvement <0.001) with similar results in subgroups. Discrimination was best in a combined model with proANP as well as NT-proBNP included.

CONCLUSIONS AND RELEVANCE

High plasma proANP concentrations are associated with and predict short-term and long-term all-cause mortality in acutely hospitalised patients irrespective of CVD status at admission.

Plasma N-terminal pro-brain natriuretic peptide levels are positively correlated with pulmonary arterial pressure in atrial septal defect patients

N-terminal pro-brain natriuretic peptide (NT-proBNP), a pro-hormone secreted by the myocardium in response to various stimuli, was found to be correlated with several hemodynamic parameters in pulmonary hypertension associated with systemic sclerosis. We investigated plasma NT-proBNP levels and the relationships between NT-proBNP and several hemodynamic parameters in atrial septal defect (ASD) patients with or without pulmonary arterial hypertension (PAH). We found that plasma NT-proBNP level was significantly higher in PAH group compared with the control group (5495.4±388.4 pg/ml vs 4005.1±260.5 pg/ml, P<0.05). In a multiple regression model analysis, only mean pulmonary arterial pressure was an independent predictor of NT-proBNP (standardized coefficient=0.663, P=0.002). In the PAH group, only right atrial systolic pressure was found to be positively correlated with NT-proBNP, whereas other parameters were not found to be correlated with NT-proBNP. Our data suggests that NT-proBNP might also be a predictor of the severity of pulmonary hypertension in the ASD patients.

N-terminal-pro-BNP in critically ill patients with acute respiratory failure: a prospective cohort study

BACKGROUND

The aim of this study was to evaluate the prognostic value of plasma N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) in unselected critically ill patients with acute respiratory failure (ARF).

METHODS

Prospective, observational cohort study in 25 intensive care units in Finland. This study included a total of 602 patients with laboratory samples from 958 consecutive patients with ARF treated either with invasive or with non-invasive ventilatory support (the FINNALI study). Plasma NT-pro-BNP samples were drawn after the onset of ventilatory support (day 0) and on the morning of the second day.

RESULTS

The median [interquartile ranges (IQR)] NT-pro-BNP-values were significantly higher at baseline in 90-day non-survivors than the survivors, 4378 pg/ml (1400-13,943 pg/ml) vs. 1052 pg/ml (232-4076 pg/ml), respectively. The median (IQR) NT-pro-BNP values were significantly higher in patients with chronic cardiac disease or cardiac surgery than in non-cardiac patients, 1947 pg/ml (801-4687 pg/ml) vs. 417 pg/ml (153-1735 pg/ml), respectively, if renal function was normal. With deteriorating renal function, the NT-pro-BNP values showed a significant increase. The area under curve for baseline NT-pro-BNP predicting 90-day mortality was moderate: 0.718 (95% confidence interval 0.674-0.761). Baseline NT-pro-BNP over 1765 pg/ml was independently associated with 90-day mortality by logistic regression analysis (P<0.001).

CONCLUSIONS

NT-pro-BNP on admission is commonly elevated and independently associated with 90-day mortality in critically ill ARF patients. However, the routine use of NT-pro-BNP for prognostic purpose does not seem to add value to clinical data in ARF patients.

The use of NT-proBNP assay in the management of canine patients with heart disease

The diagnosis and management of canine heart disease could be facilitated by a highly sensitive and specific laboratory test that predicts risk of morbidity and mortality, is helpful in directing therapy, easy to perform, inexpensive, and widely available. This article details if, how, and when the cardiac biomarker, N-terminal fragment of the prohormone B-type natriuretic peptide (NT-proBNP), helps in the diagnosis and management of canine heart disease. Veterinary cardiac biomarkers, specifically NT-proBNP, hold great promise. The incorporation of NT-proBNP assay into successful clinical practice requires an understanding of the science behind the technology, as well as the clinical data available to date.

Comparison of brain natriuretic peptide (BNP) and NT-proBNP in screening for pulmonary arterial hypertension in patients with systemic sclerosis

OBJECTIVE

To compare the performance of brain natriuretic peptide (BNP) and N-terminal pro-brain natriuretic peptide (NT-proBNP) in screening for pulmonary arterial hypertension (PAH) in systemic sclerosis (SSc).

METHODS

Between January 2008 and March 2009, outpatients referred to our unit and satisfying LeRoy criteria for SSc were assessed for PAH. Doppler echocardiography, BNP measurement, and NT-proBNP measurement were done concomitantly for a complete clinical, instrumental, and biochemical evaluation. Right-heart catheterization was carried out in cases of suspected PAH [estimated pulmonary arterial pressure (PAP) ≥ 36 mm Hg; diffusion capacity for carbon monoxide (DLCO) ≤ 50% of predicted value; 1-year DLCO decline ≥ 20% in absence of pulmonary fibrosis; unexplained dyspnea].

RESULTS

One hundred thirty-five patients were enrolled (124 women, 11 men; 96 limited SSc, 39 diffuse SSc); precapillary PAH was found in 20 patients (15 limited SSc, 5 diffuse SSc). The estimated PAP correlated with both BNP (R = 0.3; 95% CI 0.14-0.44) and NT-proBNP (R = 0.3, 95% CI 0.14-0.45). BNP [area under the curve (AUC) 0.74, 95% CI 0.59-0.89] was slightly superior to NT-proBNP (AUC 0.63, 95% CI 0.46-0.80) in identification of PAH, with diagnosis cutoff values of 64 pg/ml (sensitivity 60%, specificity 87%) and 239.4 pg/ml (sensitivity 45%, specificity 90%), respectively. BNP (log-transformed, p = 0.032) and creatinine (p = 0.049) were independent predictors of PAH, while NT-proBNP was not (p = 0.50).

CONCLUSION

In our single-center study, the performance of BNP was slightly superior to that of NT-proBNP in PAH screening of patients with SSc, although normal levels of these markers do not exclude diagnosis. We observed that impaired renal function is associated with an increased risk of PAH in SSc. Further multicenter studies are needed to confirm our results (ClinicalTrials.gov ID NCT00617487).

Impact of biomarker development on drug safety assessment

Drug safety has always been a key aspect of drug development. Recently, the Vioxx case and several cases of serious adverse events being linked to high-profile products have increased the importance of drug safety, especially in the eyes of drug development companies and global regulatory agencies. Safety biomarkers are increasingly being seen as helping to provide the clarity, predictability, and certainty needed to gain confidence in decision making: early-stage projects can be stopped quicker, late-stage projects become less risky. Public and private organizations are investing heavily in terms of time, money and manpower on safety biomarker development. An illustrative and "door opening" safety biomarker success story is the recent recognition of kidney safety biomarkers for pre-clinical and limited translational contexts by FDA and EMEA. This milestone achieved for kidney biomarkers and the "know how" acquired is being transferred to other organ toxicities, namely liver, heart, vascular system. New technologies and molecular-based approaches, i.e., molecular pathology as a complement to the classical toolbox, allow promising discoveries in the safety biomarker field. This review will focus on the utility and use of safety biomarkers all along drug development, highlighting the present gaps and opportunities identified in organ toxicity monitoring. A last part will be dedicated to safety biomarker development in general, from identification to diagnostic tests, using the kidney safety biomarkers success as an illustrative example.