Abstract 4140896: Variations in BNP Levels (35-100 pg/mL) and Their Implications for Predicting Future Heart Failure in Pre-clinical Stages A/B: Novel Risk Stratification Methods from the CHART-2 Study

Background: Recent revisions in the guidelines for pre-clinical heart failure (HF), particularly concerning B-type natriuretic peptide (BNP) levels between 35-100 pg/mL, indicate a more detailed approach. Research question: 1) BNP is influenced by several factors, including age, leading to potential variation in BNP's predictive value for future HF events. 2) Risk stratification for HF in the pre-HF state (BNP levels: 35-100 pg/mL) has not been established. Hypothesis: We hypothesized that variations in BNP values predicting HF events exist in association with specific clinical variables. Methods: We prospectively evaluated consecutive HF patients in Stage A/B (stage A/B: 731/4,537) from the multicenter observational CHART-2 (Chronic Heart Failure Registry and Analysis in the Tohoku District-2) Study. Previous studies identified the following parameters for BNP levels: age, body mass index (BMI), and estimated glomerular filtration rate (eGFR). We assessed their 10-year HF-related events. Results: The enrolled patients had the following characteristics: mean age 67.6±12.0 years, 71.1% male, BMI 24.2±12.0 kg/m 2 , and eGFR 67.4±19.2 ml/min/1.73m 2 . As shown in Figures 1A-C , variations in AUC and cut-off values exist in each category (A: age quartiles, B: BMI per WHO criteria, and C: eGFR). The minimum cut-off value was 38.25 pg/mL in the youngest quartile. We performed risk stratification for those with BNP values of 35-100 pg/mL (n=1412) using classification and regression tree (CART) methods, identifying these cut-off values as shown in Figure 2 . The hazard ratios (HR) for HF events were significantly higher in type 2 (age <74.5 years, eGFR <45.5 ml/min/1.73m 2 ) (HR: 3.97, 95% CI: 2.43-6.50) and 4 (age >74.5 years, BNP >50.9 pg/mL) (HR: 3.94, 95% CI: 2.88-5.38) compared to type 1 (both, P<0.001). Conclusion: Although variations in BNP cut-off values predicting HF events exist, the guideline-recommended value (>35 pg/mL) encompasses all at-risk patients in Stage A/B.