News:Data from ADHERE: BNP and Troponin are independent predictors of in-hospital mortality in patients with decompensated heart failure

December 17, 2007 By Benjamin A. Olenchock, M.D. Ph.D. [mailto:bolenchock@partners.org]

The investigators analyzed ADHERE data collected between April 2003 and December 2004 from 191 hospitals. Admission biomarker data was available for 42,636 patients. For the primary analysis, patients were classified as BNP level above or below the median (840 pg/ml) and troponin as positive or negative. Data from sites that measure troponin-T and troponin-I were combined. A multivariate analysis was done adjusting for age, gender, systolic blood pressure, blood urea nitrogen, creatinine, sodium, pulse, and dyspnea at rest.

Patients with elevated BNP were slightly older, more likely to have known coronary artery disease or chronic kidney disease, and have elevated blood urea nitrogen and creatinine. Patients with elevated troponin were more likely to have suspected acute coronary syndrome in addition to heart failure, tachycardia, and lower mean blood pressure. Troponin-positive patients were more likely to receive nitroglycerine, patients with elevated troponin and BNP were more likely to have received inotropes, and almost all patients received intravenous diuretics.

In anadjusted analyses, in-hospital mortality was lowest in patients with low BNP and negative troponin (2.2%). Mortality rates were similar in patients with only elevated BNP (4.45%) or elevated troponin (4.8%), whereas elevations in both biomarkers was associated with higher mortality rates (10.2%). There was a similar trend between biomarkers and ICU admission, however elevations in only troponin was more highly associated with ICU admission than was elevation of only BNP (29% vs. 17%). In adjusted analyses, there was no interaction between BNP and troponin, i.e. both provided additive prognostic information. Adjusted odds ratios for in-hospital mortality: BNP (1.6, CI 1.43 to 1.80, p<0.0001); positive troponin (1.85, CI 1.57 to 2.18, p<0.0001); elevations in both biomarkers (3.0, CI 2.47 to 3.66, p<0.0001).

The clinical use of cardiac biomarkers is well-established for risk stratification and prognosis in acute coronary syndromes. Elevations in BNP levels have been shown to predict short-term mortality in heart failure, and elevations in troponin portend a poor prognosis. The current study has demonstrated that BNP and troponin provide additive prognostic information in decompensated heart failure patients.

Gregg C. Fonarow, William F. Peacock, Tamara B. Horwich, Christopher O. Phillips, Michael M. Givertz, Margarita Lopatin and Janet Wynne. Usefulness of B-Type Natriuretic Peptide and Cardiac Troponin Levels to Predict In-Hospital Mortality from ADHERE. Am J Cardiol In Press, Corrected Proof, Available online 3 December 2007