Dynamic cardiovascular risk assessment in elderly people. The role of repeated N-terminal pro-B-type natriuretic peptide testing

Objectives: This study sought to determine whether serial measurement of N-terminal pro-B-type natriuretic peptide (NT-proBNP) in community-dwelling elderly people would provide additional prognostic information to that from traditional risk factors.

Background: Accurate cardiovascular risk stratification is challenging in elderly people.

Methods: NT-proBNP was measured at baseline and 2 to 3 years later in 2,975 community-dwelling older adults free of heart failure in the longitudinal CHS (Cardiovascular Health Study). This investigation examined the risk of new-onset heart failure (HF) and death from cardiovascular causes associated with baseline NT-proBNP and changes in NT-proBNP levels, adjusting for potential confounders.

Results: NT-proBNP levels in the highest quintile (>267.7 pg/ml) were independently associated with greater risks of HF (hazard ratio [HR]: 3.05; 95% confidence interval [CI]: 2.46 to 3.78) and cardiovascular death (HR: 3.02; 95% CI: 2.36 to 3.86) compared with the lowest quintile (<47.5 pg/ml). The inflection point for elevated risk occurred at NT-proBNP 190 pg/ml. Among participants with initially low NT-proBNP (<190 pg/ml), those who developed a >25% increase on follow-up to >190 pg/ml (21%) were at greater adjusted risk of HF (HR: 2.13; 95% CI: 1.68 to 2.71) and cardiovascular death (HR: 1.91; 95% CI: 1.43 to 2.53) compared with those with sustained low levels. Among participants with initially high NT-proBNP, those who developed a >25% increase (40%) were at higher risk of HF (HR: 2.06; 95% CI: 1.56 to 2.72) and cardiovascular death (HR: 1.88; 95% CI: 1.37 to 2.57), whereas those who developed a >25% decrease to <or=190 pg/ml (15%) were at lower risk of HF (HR: 0.58; 95% CI: 0.36 to 0.93) and cardiovascular death (HR: 0.57; 95% CI: 0.32 to 1.01) compared with those with unchanged high values.

Conclusions: NT-proBNP levels independently predict heart failure and cardiovascular death in older adults. NT-proBNP levels frequently change over time, and these fluctuations reflect dynamic changes in cardiovascular risk.