The aim was to evaluate the usefulness of urinary N-terminal fragment of B-type natriuretic peptide (NT-proBNP) measurement for predicting the presence of left ventricular hypertrophy (LVH) in 160 asymptomatic patients with essential hypertension. The urinary NT-proBNP/creatinine ratio was higher in patients with LVH than in either those without LVH (P< .0001) or control subjects (P< .0001). Multivariate linear regression analysis identified age (P=.034), left ventricular mass index (P=.026) and serum NT-proBNP level (P=.001) as predictors of the urinary peptide level. The area under the curve for the NT-proBNP/creatinine ratio was 0.71+/-0.04 (P< .0001) for identifying LVH. Logistic regression analysis showed that the NT-proBNP: creatinine ratio was a predictor of LVH (odds ratio=4.074; P=.009). In conclusion, the urinary NT-proBNP concentration is a new marker that could be useful for identifying LVH in subjects with essential hypertension.