Abstract 13220: Serial Measurement of NT-proBNP but not Cardiac Troponin T Improves Risk Stratification in the Community: Results from the Rancho Bernardo Study
Introduction: Natriuretic peptides and cardiac troponins (TnT) provide prognostic information on cardiovascular disease (CVD) risk in diverse populations. Because NTproBNP levels reflect cardiac pathophysiology but also are subject to significant intra-individual fluctuation, we hypothesized that serial measurements of NTproBNP would improve prognostication in a population of relatively healthy community-dwelling older adults.
Methods: This is a prospective study of the 911 men and women (mean age 72 ± 9 yrs) who attended the 1992–96 and 1997–99 Rancho Bernardo Study visits, and had NTproBNP and TnT measured at both (mean interval 4 ± 1 yr). Participants were grouped by quintile of % change in NTproBNP. TnT level ≥0.01 ng/mL was considered detectable. Cox proportional hazard models, adjusted for traditional CVD risk factors, BMI, and log(creatinine clearance), were used to assess risk of CVD mortality.
Results: Over a mean 7 ± 1 years of follow-up, 87 cardiovascular deaths occurred. Baseline NTproBNP and TnT levels were independent predictors of CVD mortality (adjusted HR per consecutive quintiles of NTproBNP 1.7 [95% CI 1.4–2.1, p for linear trend <0.001]; HR for detectable TnT 6.4 [1.9–22.0], p=0.001). The Figure depicts CVD mortality by quintile of % change in NTproBNP. In adjusted models including adjustment for baseline NTproBNP level, participants in the highest quintile of change were at significantly higher risk than all other quintiles (HR vs lowest 3.1 [1.5–6.3], p=0.002), while those whose NTproBNP increased less than 128%, or decreased, had similar outcomes. Further adjusting for detectable TnT at either visit did not affect results, and TnT was not a significant predictor of outcome after incorporation of change in NTproBNP level.
Conclusion: Serial measurements of NTproBNP improve risk stratification in a population of community-based elderly individuals, beyond a baseline measurement, traditional risk factors, and serial troponin levels.
- © 2010 by American Heart Association, Inc.