Use Of B-type Natriuretic Peptide Research Articles

2009 Focused Update: ACCF/AHA Guidelines for the Diagnosis and Management of Heart Failure in Adults

2009;53;1343-1382; originally published online Mar 26, 2009; J. Am. Coll. Cardiol. Rahko, Marc A. Silver, Lynne Warner Stevenson, and Clyde W. Yancy Francis, Theodore G. Ganiats, Marvin A. Konstam, Donna M. Mancini, Peter S. Mariell Jessup, William T. Abraham, Donald E. Casey, Arthur M. Feldman, Gary S. Heart and Lung Transplantation Developed in Collaboration With the International Society for Guidelines Cardiology Foundation/American Heart Association Task Force on Practice Management of Heart Failure in Adults: A Report of the American College of 2009 Focused Update: ACCF/AHA Guidelines for the Diagnosis and This information is current as of August 30, 2010 http://content.onlinejacc.org/cgi/content/full/53/15/1343 located on the World Wide Web at: The online version of this article, along with updated information and services, is

B-Type Natriuretic Peptide and Weaning From Mechanical Ventilation

In Brief The purpose of this review is to describe the physiology and usefulness of B-type natriuretic peptide (BNP) during weaning from mechanical ventilation. BNP is a powerful diagnostic and prognostic tool for right and left heart failure. BNP levels correlate with left ventricle filling pressures and help to tailor the treatment to the individual needs of patients with chronic or decompensated heart failure. Although cardiac dysfunction is the most important source of BNP variations in critically ill patients, other major factors include renal failure, sepsis, subarachnoid hemorrhage, and heart surgery. Cardiovascular dysfunction is common during weaning from mechanical ventilation. The complex pathophysiology of weaning-induced cardiovascular dysfunction involves changes in intrathoracic pressures and cardiac loading conditions. The main clinical consequences are acute pulmonary edema and/or myocardial ischemia. Conventional tools used to diagnose cardiovascular dysfunction (pulmonary artery catheterization and echocardiography) raise technical challenges in patients who are being weaned off mechanical ventilation, a fact that has generated interest in BNP. Recent data suggest that BNP may predict the outcome of weaning from assisted mechanical ventilation. In addition, BNP variations during spontaneous breathing trial may improve the predictive value of the trial on weaning outcome and may help to determine whether weaning failure is caused by cardiovascular dysfunction. The potential benefits of incorporating BNP assays into a weaning protocol aimed at optimizing fluid balance and treating weaning-induced cardiovascular dysfunction deserve further investigation. B-type natriuretic peptide is a reliable marker for left and right ventricular failure. B-type natriuretic peptide assays may help to identify cardiovascular dysfunction as the cause of difficulties in weaning patients off mechanical ventilation. The potential benefits of incorporating B-type natriuretic peptide assays into a weaning protocol deserve investigation.

Natriuretic Peptides: Biochemistry, Physiology, Clinical Implication

In the past years, the interest of theorists and clinicians has steadily increased in the myocardially secreted hormones – natriuretic peptides. At the Congress of the European Society of Anesthesiology (Munich, 2007), B-type natriuretic peptides were included into the list of the parameters of perioperative laboratory monitoring that is expedient in the practice of anesthetists and resuscitation specialists. The literature review shows the history of discovery and identification of different types of natriuretic peptides and considers the matters of their biochemistry. It also details information on the synthesis, secretion, and clearance of these peptides, as well as their receptor apparatus in various organs and tissues. The physiology of the regulatory system is described, as applied to the cardiovascular, excretory, central nervous systems, and the neuroendocrine one. Special attention is given to the current publications on the control of B-type natriuretic peptides as biomarkers of cardiac dysfunction. The diagnostic and prognostic values of peptides are analyzed in chronic circulatory insufficiency, coronary heart disease, and other car-diological and non-cardiological diseases. The prognostic value of elevated B-type natriuretic peptide levels in cardiac surgery is separately considered. It is concluded that the changes in the level of B-type natriuretic peptides in different clinical situations are the subject of numerous researches mainly made in foreign countries. The bulk of these researches are devoted to the study of peptides in cardiology and other areas of therapy. Studies on the use of peptides in reanimatology are relatively few and their results are rather discordant. The foregoing opens up wide prospects for studying the use of B-type natriuretic peptides in Russian intensive care and anesthesiology. Key words: natriuretic peptides, brain nautriuretic peptides, NT-proBNP.

B-type natriuretic peptide is a long-term predictor of all-cause mortality, whereas high-sensitive C-reactive protein predicts recurrent short-term troponin T positive cardiac events in chest pain patients: a prognostic study

BackgroundFew studies have addressed whether the combined use of B-type natriuretic peptide (BNP) and high-sensitive C-reactive protein (hsCRP) improves risk stratification for mortality and cardiovascular events in a population with chest pain and suspected acute coronary syndromes (ACS). Therefore, we wanted to assess the incremental prognostic value of these biomarkers with respect to long-term all-cause mortality and recurrent troponin T (TnT) positive cardiac events in 871 patients admitted to the emergency department.MethodsBlood samples were obtained immediately following admission.ResultsAfter a follow-up period of 24 months, 129 patients had died. The BNP levels were significantly higher among patients dying than in long-term survivors (401 (145–736) versus 75 (29–235) pq/mL [median, 25 and 75% percentiles], p = 0.000). In a multivariable Cox regression model for death within 2 years, the hazard ratio (HR) for BNP in the highest quartile (Q4) was 5.13 (95% confidence interval (CI), 1.97–13.38) compared to the lowest quartile (Q1) and was associated with all-cause mortality above and beyond age, congestive heart failure and the index diagnosis ST-segment elevation myocardial infarction. HsCRP rendered no prognostic information for all-cause mortality. However, within 30 days, the adjusted HR for patients with recurrent TnT cardiac positive events hsCRP in Q4 was 14.79 (95% CI, 1.89–115.63) compared with Q1 and was associated with recurrent ischemic events above and beyond age, hypercholesterolemia and TnT values at admission.ConclusionBNP may act as a clinically useful biomarker when obtained at admission in an unselected patient population following hospitalization with chest pain and potential ACS, and may provide complementary prognostic information to established risk determinants at long-term follow-up. Our data do not support the hypothesis that the additional assessment of hsCRP will lead to better risk stratification for survival than BNP alone.Trial registrationNCT00521976

The use of natriuretic peptides in the intensive care unit

B-type natriuretic peptides are quantitative markers of heart failure (and/or cardiac stress) that summarize the extent of systolic and diastolic left ventricular dysfunction, valvular dysfunction, and right ventricular dysfunction. Based on the observation that heart failure is common albeit difficult to diagnose in the ICU, several studies have begun to evaluate the potential use of B-type natriuretic peptides in various ICU settings. Previous pilot studies have examined the use of B-type natriuretic peptide in the differential diagnosis of hypoxemic respiratory failure, to differentiate cardiogenic from noncardiogenic shocks or to predict fluid responsiveness, to assess myocardial dysfunction and prognosis in patients with severe sepsis, and to predict ventilatory weaning failure. Although previous studies were small, they highlight the potential of using B-type natriuretic peptides as a noninvasive easily available tool to quantify cardiac stress.

THE USEFULNESS OF B-TYPE NATRIURETIC PEPTIDE IN THE EARLY DIAGNOSIS OF RIGHT VENTRICULAR INFARCTION

PURPOSE: 19–51% of inferior acute myocardial infarction(AMI) patients combine with right ventricular infarction(RVI). RVI is associated with a highly increased in-hospital mortality. Therefore, early diagnosis of RVI in inferior acute myocardial infarction is very important. This study was planned to investigate the usefulness of B-type natriuretic peptide(BNP) in the early diagnosis of RVI.

The use of B-type natriuretic peptide in the management of patients with atrial fibrillation and dyspnea

The utility of B-type natriuretic peptide (BNP) testing in patients with atrial fibrillation (AF) is poorly defined. We analyzed patients ( n = 452) included in the BNP for Acute Shortness of Breath Evaluation (BASEL) study. Patients were randomly assigned to a diagnostic strategy with or without the use of BNP. Ninety-nine patients presented with AF ( n = 48 BNP group; n = 51 control group). Although comparable with respect to gender and cardiopulmonary comorbidity, patients with AF were older and more often had heart failure as the cause of dyspnea. In addition, patients with AF had higher in-hospital mortality (13% versus 6%, P = 0.012). The use of BNP significantly reduced time to discharge (BNP group median 8 days [1–16] versus 12 days [IQR 4–21] control group; P = 0.046) in patients with AF. Initial total treatment costs (median) were $4239 [769–7422] in the BNP group and $5940 [4024–10848] in the control group ( P = 0.041). These benefits were maintained after 90 days: patients in the BNP group had spent fewer days in hospital (10 days [2–21] versus 15 days [IQR 9–27]; P = 0.022) and induced lower total treatment costs ($4790 [1260–9387] versus $7179 [4311–13173]; P = 0.016). In conclusion, the use of BNP seems to improve the management of patients with AF presenting with dyspnea.

Biomarkers in heart failure management

Purpose of review Recent literature on the role of biomarkers in heart failure is reviewed, focusing on B-type natriuretic peptide. Recent findings Knowledge of the processes which increase ventricular stress, thus increasing B-type natriuretic peptide, is key to appropriate utilization and interpretation of B-type natriuretic peptide levels. B-type natriuretic peptide is a useful adjunct to confirm or rule out heart failure. B-type natriuretic peptide is a robust prognostic indicator in all stages of heart failure, with prognostic significance in patients undergoing cardiac and noncardiac surgery, and in those with acute coronary syndromes. Serial B-type natriuretic peptide testing predicts outcomes in hospitalized patients with heart failure. The role of B-type natriuretic peptide in screening high-risk populations is promising, but its use in unselected populations is unclear. There is increasing evidence that the use of B-type natriuretic peptide to guide heart failure management is associated with improved clinical outcomes and reduced health costs. Summary Biomarkers play an important role in heart failure, but there remain unanswered questions regarding optimization of their use. They should be used as an adjunct to, not replacement for, clinical assessment. Currently available B-type natriuretic peptide assays have limitations relating to clinical variability and assay specificity. Other neurohormonal, inflammatory and metabolic markers may add complementary information to that provided by currently available B-type natriuretic peptide assays.

Biomarkers in heart failure management

Recent literature on the role of biomarkers in heart failure is reviewed, focusing on B-type natriuretic peptide. Knowledge of the processes which increase ventricular stress, thus increasing B-type natriuretic peptide, is key to appropriate utilization and interpretation of B-type natriuretic peptide levels. B-type natriuretic peptide is a useful adjunct to confirm or rule out heart failure. B-type natriuretic peptide is a robust prognostic indicator in all stages of heart failure, with prognostic significance in patients undergoing cardiac and noncardiac surgery, and in those with acute coronary syndromes. Serial B-type natriuretic peptide testing predicts outcomes in hospitalized patients with heart failure. The role of B-type natriuretic peptide in screening high-risk populations is promising, but its use in unselected populations is unclear. There is increasing evidence that the use of B-type natriuretic peptide to guide heart failure management is associated with improved clinical outcomes and reduced health costs. Biomarkers play an important role in heart failure, but there remain unanswered questions regarding optimization of their use. They should be used as an adjunct to, not replacement for, clinical assessment. Currently available B-type natriuretic peptide assays have limitations relating to clinical variability and assay specificity. Other neurohormonal, inflammatory and metabolic markers may add complementary information to that provided by currently available B-type natriuretic peptide assays.

Usefulness of B-Type Natriuretic Peptide and Cardiac Troponin Levels to Predict In-Hospital Mortality from ADHERE

B-type natriuretic peptide (BNP) and cardiac troponin (Tn) I or T have been demonstrated to provide prognostic information in patients with acute coronary syndromes. Whether admission BNP and Tn levels provide additive prognostic value in acutely decompensated heart failure (HF) has not been well studied. Hospitalizations for HF from April 2003 to December 2004 entered into ADHERE were analyzed. BNP assessment on admission was performed in 48,629 (63%) of 77,467 hospitalization episodes. Tn assessment was performed in 42,636 (88%) of these episodes. In-hospital mortality was assessed using logistic regression models adjusted for age, gender, blood urea nitrogen, systolic blood pressure, creatinine, sodium, pulse, and dyspnea at rest. Median BNP was 840 pg/ml (interquartile range 430 to 1,730). Tn was increased in 2,370 (5.6%) of 42,636 HF episodes. BNP above the median and increased Tn were associated with significantly increased risk of in-hospital mortality (odds ratios [OR] 2.09 and 2.41 respectively, each p value <0.0001). Mortality was 10.2% in patients with BNP >or=840/Tn increased compared with 2.2% with BNP <840/Tn not increased (OR 5.10, p <0.0001). After covariate adjustment, mortality risk remained significantly increased with BNP >or=840/Tn not increased (adjusted OR 1.56, 95% confidence interval 1.40 to 1.79, p <0.0001), BNP <840/Tn increased (adjusted OR 1.69, 95% confidence interval 1.17 to 2.45, p = 0.006), and BNP >or=840/Tn increased (adjusted OR 3.00, 95% confidence interval 2.47 to 3.66, p <0.0001). Admission BNP and cardiac Tn levels are significant, independent predictors of in-hospital mortality in acutely decompensated HF. Patients with BNP levels >or=840 pg/ml and increased Tn levels are at particularly high risk for mortality. In conclusion, a multimarker strategy for the assessment of patients hospitalized with HF adds incremental prognostic information.

Evidence for the use of B-type natriuretic peptides for screening asymptomatic populations and for diagnosis in primary care

Objectives To determine the screening and diagnostic properties of BNP and NT-proBNP for heart failure in primary care. Design and methods We conducted a systematic review of randomized control trials and observational (cohort or case–control) studies of heart failure detection using B-type natriuretic peptides published in English from January 1989 to February 2005. We extracted or calculated sensitivity, specificity, positive and negative likelihood ratios, area under the receiver–operator characteristic curve and diagnostic odds ratio (DOR). Results We included 17 studies (7 screening, 9 diagnosis in primary care or specialised clinic, 1 both). There was considerable heterogeneity within the study populations, reference standard for diagnosis, and B-type natriuretic peptide decision point. Sensitivity ranged from 26% to 98%; and specificity from 44% to 88%. For screening, the Diagnostic Odds Ratio (DOR) ranged from 2.7 to 29, and for diagnosis from 2.8 to 137. Conclusions The performance characteristics of B-type natriuretic peptides measurement are not suitable for screening asymptomatic patients. For diagnosis in primary care, low B-type natriuretic peptide values may be used to rule-out heart failure but, due to poor specificity, high values cannot be used to rule-in the condition.

The Biologic Variability of B-Type Natriuretic Peptide and N-Terminal Pro-B-Type Natriuretic Peptide in Stable Heart Failure Patients

There are conflicting data on the usefulness of B-type natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) in the optimization of therapy for heart failure (HF). Discordant results may be explained by the intra-individual variability of these peptides. This study evaluates the intraindividual variability of BNP and NT-proBNP and the impact of the covariates of age, sex, and renal function. Stable HF patients attending our unit were included. Blood samples were drawn 1 hour apart on 2 occasions 1 week apart. Forty-five patients were enrolled (69.6 +/- 12.1 years, 64% male, 84% systolic HF). Within-hour and within-week intraindividual variability were: 6.9% and 21.1% for NT-proBNP; 14.6% and 28.4% for BNP (P < .01 for within-hour comparison of BNP and NT-proBNP). Reference change values over 1 week for NT-proBNP and BNP were 49.2% and 66.2%, respectively. There were no significant relationships identified between variability and age, gender, or glomerular filtration rate. There is considerable intraindividual variability in these peptides in stable HF patients. Changes of approximately 50% and 66% for NT-proBNP and BNP from week to week are needed to indicate an altered clinical status and caution should be exercised in interpreting serial changes in these peptide levels when monitoring patient responses to treatment or clinical status.

THE VALIDITY OF B-TYPE NATRIURETIC PEPTIDE BLOOD LEVELS TO DETECT HEART FAILURE IN HEART TRANSPLANT PATIENTS.

Purpose The usefulness of B-type natriuretic peptide (BNP) to detect symptomatic heart failure in the nontransplanted patient has been well established. However, the clinical utility of measuring BNP levels following heart transplantation is unclear. The purpose of our study was to determine whether BNP levels correlate with symptomatic heart failure, confirmed hemodynamically, in cardiac transplant recipients. Methods We evaluated 130 consecutive patients transplanted between July 2001 and November 2003 whose BNP levels were assessed at time of right heart catheterization and clinical examination. BNP values drawn within 8 weeks prior to an initial episode of treated rejection were also identified (n = 10). Heart failure was defined as both the presence of symptoms (dyspnea, edema, or documented increase in diuretic dose) and a PCWP 15 mm Hg. BNP samples taken during the first 3 months post-transplant (when levels are known to be elevated), as well as patients with renal failure (Cr > 1.9) were excluded. Patients had an average follow-up of 28 months. Results Of the 130 patients, 67 patients had 124 BNP measurements with a PCWP 15. The BNP was 150 pg/mL in only 42 of 124 (33.8%) measurements. In 29 patients with symptomatic heart failure and PCWP 15, the BNP was 150 on only 19 of 42 (45.2%) occasions. Therefore, a BNP level of 150 was found to have a sensitivity of only 45.2%, a specificity of 64.9%, a positive predictive value of 3.7%, and a negative predictive value of 2.4% for the detection of heart failure in heart transplant recipients. In addition, a BNP value 150 within 8 weeks of a clinically significant episode of rejection was noted in only 5 of 10 (50%) cases. Conclusions BNP levels are not effective in determining clinically relevant heart failure following heart transplantation. In addition, it does not appear to predict rejection. The discrepancy between the utility of BNP in detecting heart failure in the transplant and nontransplant population may be due to denervated cardiac physiology but requires further investigation.

Biomarker-based strategy for screening right ventricular dysfunction in patients with non-massive pulmonary embolism

To evaluate the usefulness of B-type natriuretic peptide and troponin I measurements in predicting right ventricular dysfunction (RVD) in non-massive pulmonary embolism. Prospective observational study. University-affiliated emergency unit, cardiology and pneumology departments. Sixty-seven patients admitted because of acute pulmonary embolism, without shock on admission, completed the study. Blood samples and echocardiography were obtained on admission for subsequent and independent assessment of B-type natriuretic peptide (BNP) and troponin I levels as well as RVD. Echocardiographic RVD was diagnosed in 36 patients and was severe in 13 on admission. BNP and troponin I levels were higher in patients with RVD than in those with no RVD [62 (27-105) vs. 431 (289-556) pg/ml for BNP, p<0.001; 0.01 (0-0.09) vs. 0.16 (0.03-0.32) microg/l for troponin I, p=0.005]. The area under the receiving operating characteristic curve (AUC) for diagnosing RVD was 0.93 for BNP and 0.72 for troponin I. The troponin I level increased further when RVD was severe, compared with moderate, and the AUC was 0.91 for identifying severe RVD. Diagnoses of RVD and severe RVD were ruled out by BNP<or=100 pg/ml (30% of patients) and troponin I 0.10 microg/l (58% of patients), respectively. In-hospital death or circulatory failure occurred in nine patients; all had echographic RVD and level of BNP >100 pg/ml and troponin I >0.10 microg/l. In hemodynamically stable pulmonary embolism, BNP/troponin I measurement is helpful on admission, especially for ruling out RVD, i.e. patients with in-hospital high-risk.

The use of B-type natriuretic peptides in the detection of myocardial ischemia in settings with rapid access to coronary angiography

The aim of this study was to evaluate serial measurements of B-type natriuretic peptide (BNP) and NT-proBNP levels in the detection of myocardial ischemia. A total of 62 consecutive male patients referred for stress echocardiography in a tertiary care cardiology center were enrolled. Inducible myocardial ischemia was detected in 15 patients (24%). BNP and NT-proBNP levels were significantly lower in patients with ischemia compared to those without ischemia throughout exercise testing and during recovery ( p < 0.05 for all comparisons). Major differences in baseline characteristics including age and higher incidence of comorbidities including hypertension and kidney disease in patients without ischemia apparently outweighed myocardial ischemia as trigger for BNP and NT-proBNP secretion. The same factors may have induced a selection bias in the decision to offer direct coronary angiography or initial stress testing. In conclusion, BNP and NT-proBNP are not helpful in the evaluation of male patients with suspected myocardial ischemia in a tertiary care cardiology center with rapid access to coronary angiography.

Diagnostic Usefulness of B-Type Natriuretic Peptide and Functional Consequences of Muscle Alterations in COPD and Chronic Heart Failure

COPD affects up to one third of patients with chronic heart failure. The coexistence of COPD and chronic heart failure presents clinicians with diagnostic and therapeutic challenges. Measurement of B-type natriuretic peptide plasma levels facilitates the diagnosis of acute dyspnea in patients known to have both COPD and chronic heart failure. Patients with COPD or chronic heart failure have skeletal muscle abnormalities that limit functional capacity independently from primary organ failure. Exercise training reverses skeletal muscle abnormalities in patients with COPD or chronic heart failure and may be particularly indicated in patients with coexistent COPD and chronic heart failure.

Accuracy of B-Type Natriuretic Peptide Tests to Exclude Congestive Heart Failure

Congestive heart failure (CHF) is a major public health problem. The use of B-type natriuretic peptide (BNP) tests shows promising diagnostic accuracy. Herein, we summarize the evidence on the accuracy of BNP tests in the diagnosis of CHF and compare the performance of rapid enzyme-linked immunosorbent assay (ELISA) and standard radioimmunosorbent assay (RIA) tests. We searched electronic databases and the reference lists of included studies, and we contacted experts. Data were extracted on the study population, the type of test used, and methods. Receiver operating characteristic (ROC) plots and summary ROC curves were produced and negative likelihood ratios pooled. Random-effect meta-analysis and metaregression were used to combine data and explore sources of between-study heterogeneity. Nineteen studies describing 22 patient populations (9 ELISA and 13 RIA) and 9093 patients were included. The diagnosis of CHF was verified by echocardiography, radionuclide scan, or echocardiography combined with clinical criteria. The pooled negative likelihood ratio overall from random-effect meta-analysis was 0.18 (95% confidence interval [CI], 0.13-0.23). It was lower for the ELISA test (0.12; 95% CI, 0.09-0.16) than for the RIA test (0.23; 95% CI, 0.16-0.32). For a pretest probability of 20%, which is typical for patients with suspected CHF in primary care, a negative result of the ELISA test would produce a posttest probability of 2.9%; a negative RIA test, a posttest probability of 5.4%. The use of BNP tests to rule out CHF in primary care settings could reduce demand for echocardiography. The advantages of rapid ELISA tests need to be balanced against their higher cost.

Use of B-type natriuretic peptide in the management of acute dyspnea in patients with pulmonary disease: Am Heart J 2006;151:471–7

Use of B-type natriuretic peptide in the management of acute dyspnea in patients with pulmonary disease: Am Heart J 2006;151:471–7

Use of B-Type Natriuretic Peptide Testing in a Community Teaching Hospital 4 Years After Implementation and Agreement of Results with Discharge Diagnoses

We previously reported on the use of B-type natriuretic peptide (BNP) testing in the 400-bed Hennepin County Medical Center at the inception of testing in August 2001 (1). We now describe its use and report the agreement of the results with diagnoses in the patient records in this urban teaching hospital 4 years later. We queried all BNP orders for June through August 2005 and found 975 test orders on 608 patients. To determine a diagnosis of heart failure, physician discharge dictations and ICD-9 codings were reviewed after Institutional Review Board approval. Final diagnoses were likely influenced by the BNP concentrations in some cases, potentially leading to overestimation of apparent diagnostic accuracy. The Biosite Triage and Beckman Coulter Access BNP assays were performed according to the manufacturers’ guidelines and were highly correlated ( r = 0.99; n = 50), with Bland–Altman analysis demonstrating a mean (SD) difference of 16 (23) ng/L. Total imprecision (CV) near the 100 …

The use of B-type natriuretic peptide in the management of patients with diabetes and acute dyspnoea

The aim of this study was to determine the impact of measurement of B-type natriuretic peptide (BNP) levels on the management of patients with diabetes presenting with acute dyspnoea. This study evaluated the subgroup of 103 patients with diabetes included in the B-type Natriuretic Peptide for Acute Shortness of Breath Evaluation (BASEL) study (n=452). Patients were randomly assigned to a diagnostic strategy with (n=47, BNP group) or without (n=56, control group) the use of BNP levels assessed by a rapid bedside assay. Time to discharge and total cost of treatment were recorded as the primary endpoints. Although similar with regard to age and sex, patients with diabetes more often had pre-existing cardiovascular and renal disease and heart failure as the cause of acute dyspnoea compared with patients without diabetes. In addition, medical and economic outcomes were worse in patients with diabetes. The use of BNP levels significantly reduced time to discharge (median 9 days [interquartile range (IQR) 2-16] in the BNP group vs 13 days [IQR 8-22] in the control group; p=0.016). At 30 days, the diabetic patients in the BNP group had spent significantly fewer days in hospital compared with the diabetic patients in the control group (9 days [IQR 2-19] vs 16 days [IQR 8-24], respectively; p=0.008). Total treatment costs at 30 days were US$5,705 (IQR 2,285-9,137) in the BNP group and US$7,420 (IQR 4,194-11,966) in the control group (p=0.036). The results of this study indicate that measurement of BNP levels improves the management of patients with diabetes presenting with acute dyspnoea.