The potential role of NT-proBNP in screening for and predicting prognosis in heart failure: a survival analysis
C J Taylor, A K Roalfe, R Iles, F D R Hobbs
Objective: To determine the potential role of N-terminal pro-B-type natriuretic peptide (NT-proBNP) in screening for and predicting prognosis in heart failure by examining diagnosis and survival of patients with a raised NT-proBNP at screening. Design: Survival analysis. Setting Prospective: substudy of the Echocardiographic Heart of England Screening study (ECHOES) to investigate 10-year survival in participants with an NT-proBNP level at baseline. Participants 594 participants took part in the substudy. Records of all participants in the ECHOES cohort were flagged during the screening phase which ended on 25 February 1999. All deaths until 25 February 2009 were coded. Outcome measures: Logistic regression was used to examine whether NT-proBNP is useful in predicting heart failure at screening after adjustment for age, sex and cohort. Kaplan-Meier curves and log rank tests were used to compare survival times of participants according to NT-proBNP level. Cox regression was carried out to assess the prognostic effect of NT-proBNP after allowing for significant covariates and receiver operator curves were used to determine test reliability. Results: The risk of heart failure increased almost 18-fold when NT-proBNP was 150 pg/mL or above (adjusted OR=17.7, 95% CI 4.9 to 63.5). 10-year survival in the general population cohort was 61% (95% CI 48% to 71%) for those with NT-proBNP ≥150 pg/mL and 89% (95% CI 84% to 92%) for those below the cut-off at the time of the initial study. After adjustment for age, sex and risk factors for heart failure, NT-proBNP level ≥150 pg/mL was associated with a 58% increase in the risk of death within 10 years (adjusted HR=1.58, 95% CI 1.09 to 2.30). Conclusions: Raised NT-proBNP levels, when screening the general population, are predictive of a diagnosis of heart failure (at a lower threshold than guidelines for diagnosing symptomatic patients) and also predicted reduced survival at 10 years.