Determination of the B-type Natriuretic Peptide Level as a Criterion for Abnormalities in Japanese Individuals in Routine Clinical Practice: The J-ABS Multi-center Study (Japan Abnormal BNP Standard)

Objective The present study was undertaken to establish a useful range for the B-type natriuretic peptide (BNP) level, with the ultimate goal of determining a cut-off BNP level that will make it possible to identify patients with clinically important organic heart disorders among patients encountered in clinical practice. Methods A total of 11,967 outpatients were evaluated for this study, and, after applying the exclusion criteria, 361 patients were finally recruited for the analysis. Compared to the factors of gender and body mass index, aging was considered to be an indispensable factor in this analysis. The 'median' plasma BNP level was found to increase slowly with age, but remained lower than 30 pg/mL, even in patients aged 60 years or older. In contrast, the overall '95th percentile' of the plasma BNP level in the patients younger than 60 years was 41 pg/mL, which increased to 139.8 pg/mL in the patients aged 60 years or older. Conclusion These findings suggest that the lower range of the BNP level allowing for identification of patients with clinically important organic heart disorders increases with age; however, it might be appropriate to adopt a level of approximately 40 pg/mL, even in elderly patients, in order to avoid any possible age-related effects of diastolic dysfunction or other factors.