Blood pressure and stroke in heart failure in the REasons for Geographic And Racial Differences in Stroke (REGARDS) study

Abstract

Background and purpose: The prevalence of stroke is increased in individuals with heart failure (HF). The stroke mechanism in HF may be cardiogenic embolism or cerebral hypoperfusion. Stroke risk increases with decreasing ejection fraction and low cardiac output is associated with hypotension and poor survival. We examine the relationship among blood pressure level, history of stroke/transient ischemic attack (TIA), and HF.

Methods: We compared the prevalence of self-reported history of stroke or TIA in the REasons for Geographic And Racial Differences in Stroke (REGARDS) participants with HF (as defined by current digoxin use) and without HF. We excluded participants with atrial fibrillation or missing data. We examined the relationship between HF and history of stroke/TIA within tertiles of systolic blood pressure (SBP) adjusting for patient demographic and health characteristics.

Results: Prevalent stroke/TIA were reported by 66 (26.3%) of 251 participants with and 1805 (8.5%) of 21 202 participants without HF (P<0.0001). Within each tertile of SBP, the unadjusted OR (95% CI) for prior stroke/TIA among those with HF compared with those without HF (the reference group) was, 4.0 (2.8 to 5.8) for SBP <119.5 mm Hg, 2.7 (1.8 to 3.9) for SBP >or=119.5 but <131.5 mm Hg, and 2.3 (1.6 to 3.2) for SBP >or=131.5 mm Hg. After adjustment, the relationship between prior stroke/TIA and HF remained significant only within the lowest tertile of SBP (<119.5 mm Hg; 3.0; 1.5 to 6.1).

Conclusions: The odds of prevalent self-reported stroke/TIA are increased in participants with HF and most markedly increased in participants with low SBP. Longitudinal data are needed to determine whether this reflects stroke/TIA secondary to thromboembolism from poor cardiac function or secondary to cerebral hypoperfusion.