The role of NT-proBNP in screening for atrial fibrillation in hypertensive disease

Background: Atrial fibrillation (AF) screening should be considered in elderly patients with high risk of stroke, which include individuals with hypertension. The biomarker N-terminal prohormone of brain natriuretic peptide (NT-proBNP) can predict incident AF and is increased in hypertensive individuals. The aim of this study is to investigate the incidence of screening-detected AF in elderly individuals in relation to NT-proBNP and hypertension. Methods: STROKESTOP II is a randomized controlled trial in which 75/76-years-old individuals were invited to a screening study for AF using NT-proBNP as a discriminator of high risk. In this sub-study, a prior hypertension diagnosis was self-reported by participants and measured blood pressure was stratified into hypertension-grades. Individuals with both increased blood pressure (≥140 mmHg) and NT-proBNP ≥ 125 ng/L were defined as a high-risk group. The lowest risk-group was defined as normotensive participants with NT-proBNP < 125 ng/L. Results: NT-proBNP increased gradually for every hypertension-grade above hypertension-grade 1 compared to normotensive participants. Screening-detected AF was most common in normotensive participants with increased NT-proBNP (n = 90/1922, 4.7 %), followed by patients with both NT-proBNP > 125 ng/l and SBP ≥ 140 mmHg, (AF = 65/1741, 3.7 %) compared to the low-risk group (AF = 2/1444, 0.1 %), p < 0.001. Conclusion: NT-proBNP is elevated in elderly patients with hypertension and increases with grades of hypertensive disease. NT-proBNP is a strong predictor of AF regardless of high blood pressure, and the risk for screening-detected AF is very low in participants with normal blood pressure and low NT-proBNP. A combination of blood pressure and NT-proBNP could identify suitable participants for AF screening.