B-Type Natriuretic Peptide Diagnostic Performance Varies by Ethnicity in UK African-Caribbean and South Asian Populations: An Exploratory Analysis from the E-ECHOES Study

Background Heart failure (HF) disproportionately affects ethnic minority populations in the UK, with Black African-Caribbean (AC) and South Asian (SA) individuals at increased risk of developing HF at younger ages. Current European guidelines recommend B-type natriuretic peptide (BNP) thresholds <35 pg/mL for excluding HF in symptomatic patients, but diagnostic performance across ethnic groups remains unclear. This study aimed to evaluate the discriminative performance of BNP for identifying heart failure with reduced ejection fraction (HFrEF) and mildly reduced ejection fraction (HFmrEF) in AC and SA populations residing in the UK. Methods Cross-sectional analysis of the Ethnic-Echocardiographic Heart of England Screening study (E-ECHOES). We assessed 1,164 participants (457 AC, 707 SA) aged ≥45 years. Participants underwent echocardiographic assessment, electrocardiography, and BNP measurement. Abnormal left ventricular ejection fraction (LVEF) was defined as <50%. Receiver operating characteristic (ROC) analysis determined optimal BNP cutoffs and diagnostic performance. Logistic regression assessed the incremental value of combining BNP with clinical variables. Results Eighteen participants (1.5%) had abnormal LVEF. Median BNP levels were similar between ethnic groups (AC: 11.5 pg/mL; SA: 13.6 pg/mL). For the combined cohort, BNP demonstrated moderate discriminatory ability (AUC 77.2%, 95% CI 64.6-89.8) with an optimal cutoff of 35.9 pg/mL (sensitivity 66.7%, specificity 83.6.%). In SA participants alone, BNP performance improved (AUC 86.5%, 95% CI 76.9-96.0) with a lower optimal cutoff of 28.4 pg/mL (sensitivity 81.8%, specificity 75.3%). ROC analysis in AC participants was limited by low event numbers. Combining BNP with diabetes status and ECG findings enhanced diagnostic performance across both groups (AUC 90.5%, 95% CI 84.4-96.7)3012. Conclusions BNP maintains a high negative predictive value for ruling out left ventricular dysfunction across ethnic groups (98.9-99.3%). These exploratory findings suggest that SA participants demonstrate optimal diagnostic performance at approximately 20% lower BNP threshold than current European guideline recommendations. Integration of BNP with diabetes status and ECG assessment substantially improves diagnostic accuracy in both groups. These hypothesis generating findings warrant validation in larger studies, particularly in AC populations to establish equitable diagnostic approaches for heart failure detection.