Supplementary Material for: Correlation between B-Type Natriuretic Peptide and N-Terminal pro-B-Type Natriuretic Peptide in a Large Japanese Population at Risk of Stage A Heart Failure M.Taki S.Hoshide K.Kono K.Kario 2018 <b><i>Background:</i></b> The measurements of B-type natriuretic peptide (BNP) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) are useful for ruling out heart failure and as prognostic markers in not only heart failure populations but also general populations. It is not clear whether these two biomarkers are elevated in parallel or associated with demographic characteristics in large populations at risk of stage A heart failure. Here we investigated the relationship between BNP and NT-proBNP and extended the evaluation of this association to known demographic disparities in stage A heart failure. <b><i>Methods:</i></b> Of 4,310 ambulatory patients, we analyzed the cases of the 3,643 (mean age 65 ± 11 years, 46% male, and 79% on antihypertensive medication) patients whose serum BNP and NT-proBNP levels were both measured and who had a history of and/or risk factors for cardiovascular disease from the Japan Morning Surge-Home Blood Pressure (J-HOP) Study dataset. <b><i>Results:</i></b> The median (25th–75th percentiles) BNP and NT-proBNP values were 18.7 (9.3–38.5) pg/mL and 50.3 (25.5–97.4) pg/mL. There was a significant association between log-transformed BNP and log-transformed NT-proBNP (<i>r</i> = 818, <i>p</i> < 0.001). A multiple linear regression analysis showed that log-transformed NT-proBNP was significantly associated with log-transformed BNP (beta coefficient = 0.774, <i>p</i> < 0.001). When stratified by demographic characteristics, these associations remained (all <i>p</i> < 0.001). <b><i>Conclusion:</i></b> In a large Japanese population at risk of stage A heart failure, there was a significant association between BNP and NT-proBNP after adjustment and stratification by demographics.