Plasma Brain Natriuretic Peptide is a Marker of Prognostic Functional Outcome in Non–Cardioembolic Infarction

BackgroundHigh plasma levels of brain natriuretic peptide (BNP) may also be observed in patients with non–cardioembolic infarction (CEI). We aimed to evaluate the relation between plasma BNP level, clinical parameters, and functional outcome in patients with and without CEI.MethodThis study analyzed consecutive Japanese patients with acute ischemic stroke. Correlations between plasma BNP level and conventional risk factors for ischemic stroke were examined. Values of P less than .05 were considered statistically significant.ResultsThis study analyzed 718 acute ischemic stroke patients (445 men and 273 women; mean age, 73.9 years). Mean plasma level of BNP was significantly higher for CEI (366.6 pg/ml) than for non-CEI (105.6 pg/ml; P < .01). Poor outcome (modified Rankin Scale score ≥3) at hospitalization and discharge were associated with significantly higher plasma BNP level than good outcome (modified Rankin Scale score ≤2) for both CEI and non-CEI. On multiple regression analysis, log-BNP was significantly associated with female sex, smoking, triglyceride, and creatinine clearance in CEI. In non-CEI, log-BNP was significantly associated with systolic/diastolic blood pressure, triglyceride, high-density lipoprotein cholesterol, and creatinine clearance.ConclusionIrrespective of the presence of CEI, plasma BNP offers a marker of prognostic functional outcome. We clarified the characteristics and differences associated with plasma BNP in CEI and non-CEI, and our results suggest that plasma BNP can provide a useful marker of brain damage and neurohumoral dynamics in acute ischemic stroke.