Ambulatory blood pressure and risk of new-onset atrial fibrillation in treated hypertensive patients.

The aim of this study was to evaluate the influence of clinic and ambulatory blood pressure (BP) on the occurrence of new-onset atrial fibrillation (AF) in treated hypertensive patients. We studied 2135 sequential treated hypertensive patients aged >40 years. During the follow-up (mean 9.7 years, range 0.4-20 years), 116 events (new-onset AF) occurred. In univariate analysis, clinic, daytime, nighttime, and 24-h systolic BP were all significantly associated with increased risk of new-onset AF, that is, hazard ratio (95% confidence interval) per 10 mm Hg increment 1.22 (1.11-1.35), 1.36 (1.21-1.53), 1.42 (1.29-1.57), and 1.42 (1.26-1.60), respectively. After adjustment for various covariates in multivariate analysis, clinic systolic BP was no longer associated with increased risk of new-onset AF, whereas daytime, nighttime, and 24-h systolic BP remained significantly associated with outcome, that is, hazard ratio (95% confidence interval) per 10 mm Hg increment 1.09 (0.97-1.23), 1.23 (1.10-1.39), 1.16 (1.03-1.31), and 1.22 (1.06-1.40), respectively. Daytime, nighttime, and 24-h systolic BP are superior to clinic systolic BP in predicting new-onset AF in treated hypertensive patients. Future studies are needed to evaluate whether a better control of ambulatory BP might be helpful in reducing the occurrence of new-onset AF.