Abstract and Introduction
Aims: Patients with atrial fibrillation (AF) have an increased risk of cardiovascular events and dementia, even if anticoagulated. Hypertension is highly prevalent in AF population; however, the optimal blood pressure (BP) target for AF patients remains unknown.
Methods and Results: We conducted subgroup analysis of the Systolic Blood Pressure Intervention Trial (SPRINT) to examine whether AF modified the treatment effects of intensive BP control on cardiovascular and cognitive outcomes using Cox proportional hazards regression and likelihood ratio tests. Among 9361 randomized participants, 778 (8.3%) had baseline AF, and 695 (89.3%) completed at least one follow-up cognitive assessment. Intensive BP control reduced the similar relative risk of cardiovascular events irrespective of the presence of AF, with all interaction P-values > 0.05. Patients with AF experienced a greater absolute risk reduction in the composite primary cardiovascular outcome (12.3 vs. 5.6 events per 1000 person-years) with intensive treatment, compared with those without AF. However, intensive BP control increased the risk of probable dementia in patients with AF [hazard ratio (HR), 2.22; 95% confidence interval (CI), 1.03–4.80], while reducing the dementia risk in patients without AF (HR, 0.75; 95% CI, 0.60–0.95; P = 0.009 for interaction). There were no significant interactions between the presence of AF and intensive BP treatment for mild cognitive impairment.
Conclusion: Patients with AF experienced greater absolute cardiovascular benefits with intensive BP treatment, but may need to be cautious of an increased risk of dementia. This post hoc analysis should be considered as hypothesis generating and merit further study.
Clinical Trial Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01206062.
Atrial fibrillation (AF) is a major public health burden worldwide, being associated with an increased risk of cardiovascular events, mortality, and cognitive decline. Even with effective anticoagulation, the risk of mortality remains high in patients with AF. Interventions beyond anticoagulation, are needed to further improve outcomes in AF.
Hypertension is highly prevalent in AF population, and has been identified as a modifiable risk factor for cardiovascular and cognitive risks. However, the optimal blood pressure (BP) target for AF patients remains unknown. Observational studies with a potential effect of reverse casuality, suggested a J-curve relationship between BP levels with cardiovascular outcomes and dementia risk in patients with AF.[2–4] Atrial fibrillation increases beat-to-beat BP variability, which raises the concern about the potential risk of hypoperfusion and its impact on vascular and cognitive function. A recent meta-analysis of clinical trials indicated that patients with AF derived similar relative benefits from BP-lowering treatment. Nevertheless, the achieved BP levels in these studies were higher than the current guideline recommendations. Insights into the effects of intensive BP control with lower targets on clinical outcomes are critical for informing optimal management of AF patients.
The Systolic Blood Pressure Intervention Trial (SPRINT) has demonstrated a lower risk of major cardiovascular events and probable dementia or mild cognitive impairment (MCI) with intensive treatment by targeting a systolic BP (SBP) of <120 mmHg, as compared with <140 mmHg.[7,8] We, therefore, use the SPRINT data to assess whether the effects of intensive BP control on cardiovascular and cognitive outcomes vary by the presence or absence of AF.
Europace. 2022;24(10):1560-1568. © 2022 Oxford University Press
Copyright 2007 European Heart Rhythm Association of the European Society of Cardiology (ESC). Published by Oxford University Press. All rights reserved.