Usefulness of natriuretic peptide testing for long-term risk assessment following acute ischemic stroke

Acute-phase levels of B-type natriuretic peptide (BNP) and the N-terminal fragment of the BNP prohormone (NT-pro-BNP) have been associated with mortality when measured in patients with an acute ischemic stroke; however, data regarding the longer-term value of NT-pro-BNP for long-term prognostication after ischemic stroke are limited. Two hundred sixteen patients (mean age 67 +/- 13 years) with acute ischemic stroke were seen 6 months after index admission at which time a structured evaluation including measurement of plasma NT-pro-BNP was performed. Patients were followed for 45 months, with all-cause mortality as the clinical end point. Median NT-pro-BNP concentration for the entire group was 147 pg/ml (10th to 90th percentiles 37 to 869). At follow-up 45 patients (21%) had died. NT-pro-BNP concentrations were significantly higher in decedents (308 pg/ml, 10th to 90th percentiles 74 to 2,279) than in the 171 survivors (132 pg/ml, 10th to 90th percentiles 35 to 570, p <0.001). Patients with NT-pro-BNP < or =147 pg/ml had a significantly improved survival rate on univariate analysis (p <0.001). In multivariate analysis after adjustment for age, stroke severity, heart and renal failures, levels of NT-pro-BNP were an independent predictor of mortality >6 months after stroke (adjusted hazard ratio 1.5, 95% confidence interval 1.1 to 1.9, p = 0.005). In conclusion, NT-pro-BNP concentrations measured during the stable phase after acute ischemic stroke are strongly predictive of long-term mortality.