Objective: Elevated systolic blood pressure (SBP) can significantly increase the bleeding risk in patients with atrial fibrillation (AF). However, it is unclear whether elevated diastolic blood pressure (DBP), in the presence of well-controlled SBP is also associated with bleeding. Therefore, we aimed to examine the specific relationship between DBP and bleeding in patients with AF treated with anticoagulants and had well-controlled SBP.
Methods: We analyzed data from 542 of 929 patients with nonvalvular AF (NVAF) treated with dabigatran from the Monitor System for the Safety of Dabigatran Treatment study (MISSION-AF) who had a SBP of 120–140 mm Hg at the time of enrollment. The association between DBP and bleeding was analyzed using multivariate logistic regression and smooth curve fitting (penalized spline method). Threshold saturation effect analysis was used to show the nonlinear relationship between DBP and bleeding.
Results: After 3 months of follow-up, 49 bleeding events occurred. Compared with participants with DBP <80 mm Hg, those with DBP ≥80 mm Hg had a 118% higher bleeding risk [hazard ratio (HR): 2.18; 95% confidence interval (CI): 1.19, 3.98; p<0.05]. The smooth curve showed a nonlinear relationship between DBP and bleeding risk, and the inflection point of DBP was 80 mm Hg. When DBP was ≥80 mm Hg, the bleeding risk increased by 59% (HR: 1.59; 95% CI: 1.16, 2.19; p<0.05) for every 5 mm Hg increase in DBP.
Conclusion: Upon achieving an optimal SBP (120–140 mm Hg), a higher DBP might be associated with a higher bleeding risk in patients with NVAF treated with dabigatran.