The aim of this sub study of the STROKESTOP II trial, was to investigate the levels of NT-proBNP in elderly patients with hypertension/hypertension-grades and to determine if the incidence of screening-detected AF increases with high blood pressure and NT-proBNP levels (high-risk group), compared to normal blood pressure/NT-proBNP levels. This evidence concerns the gene NPPB and atrial fibrillation.