Abstract 13472: NT-proBNP is Prognostic for Stroke and Death in Atrial Fibrillation - a RELY Substudy
Background: Atrial fibrillation (AF) increases the risk of stroke and mortality. Natriuretic peptides are powerful prognostic biomarkers for mortality and cardiovascular (CV) events. The prognostic value of N-terminal pro-B-type natriuretic peptide (NT-proBNP) and its effect in addition to CHADS2 risk factors for predicting CV events in patients with AF has not been investigated previously.
Methods: In the RELY study, 18113 patients (mean age 71 years) with AF and at least one risk factor for thromboembolism were randomized to dabigatran or warfarin and followed for 2.0 years median treatment duration. We analyzed plasma concentrations of NT-proBNP, Roche Diagnostics, at randomization in 6158 patients and evaluated its association to CV events after multivariable adjustment for CHADS2 risk factors and study drug. Reference levels for NT-proBNP were measured in 940 healthy subjects in the Uppsala Longitudinal Study of Adult Men (ULSAM), a community-based cohort of 71 year old men.
Results: Median NT-proBNP levels were 805.5 ng/L in the AF population and 90.5 ng/L in the reference population. The risk for stroke and systemic embolism (SE), CV death and major bleedings increased significantly according to increasing NT-proBNP quartile groups even after multivariable adjustment for CHADS2 risk factors and study drug.
*effect of the NT-proBNP quartile groups, Cox proportional hazards model
Conclusion: NT-proBNP is considerably elevated in AF patients with risk factors for stroke compared to a healthy population of similar age. An elevated NT-proBNP level is related to a raised risk of stroke, major bleeding and mortality even after adjustment for the CHADS2 risk factors in AF patients treated with warfarin or dabigatran.
- © 2010 by American Heart Association, Inc.