Impact of blood pressure on the risk of stroke and all-cause mortality in patients with atrial fibrillation across different age groups: A nationwide population-based study.

BACKGROUND

Elevated blood pressure (BP) in patients with atrial fibrillation (AF) is strongly linked to poor outcomes.

OBJECTIVE

This study assessed the impact of BP on the risk of ischemic stroke and all-cause death in patients with AF across different age groups.

METHODS

We included 338,747 patients newly diagnosed with AF between 2009 and 2016, with national health screening data. Patients were divided into 4 age groups (40-49, 50-59, 60-69, and ≥70 years) and categorized by systolic BP (SBP) and diastolic BP (DBP) according to the 2023 European hypertension guidelines as follows: optimal BP, normal BP, high-normal BP, grade 1 hypertension, and grade ≥2 hypertension. The primary outcome was ischemic stroke, and the secondary outcome was all-cause death. We additionally performed analyses stratified by anti-hypertensive treatment status.

RESULTS

Over a median follow-up of 6.0 years (interquartile range, 4.0-8.6), 39,329 patients experienced a stroke, and 104,712 died. Stroke incidence was significantly higher in grade 1 and grade ≥2 hypertension across all age groups. Stroke risk increased with SBP ≥160 mmHg and DBP ≥90 mmHg, particularly in younger patients with elevated BP. Grade ≥2 hypertension was consistently linked to higher mortality across all age groups, whereas normal BP was associated with the lowest mortality rates. Extremely low BP was also related to a higher risk of mortality.

CONCLUSION

High BP was associated with higher risks of stroke and mortality in AF patients, especially in younger individuals. Conversely, excessively low BP was linked to higher mortality, highlighting the importance of balanced BP control in patients with AF.