Risk of Ischemic Stroke in Patients Newly Diagnosed With Heart Failure: Focus on Patients Without Atrial Fibrillation

Background: Heart failure (HF) is associated with an incremental risk of stroke, but limited real-world data exist in patients with HF without atrial fibrillation (AF). Objectives: To quantify the incremental risk of ischemic stroke among newly diagnosed patients with HF and without AF. Methods: Adults with HF and >= 18 months of enrollment before their index HF (ie, baseline period) were identified in Truven Health Analytics MarketScan Databases (January 2010-April 2015). Patients without AF during baseline and without an ischemic stroke within 14 days of the index date were propensity score matched 1:1 to individuals with neither HF nor AF and observed for ischemic stroke. A similar analysis was performed for the overall HF population. Incidence rates were compared using incidence rate ratios between HF and non-HF cohorts; Kaplan-Meier analyses with log-rank tests were used to compare incidence rates over time. Results: A total of 66,414 patients with HF were identified, of which 52,005 did not have AF. Patients with HF without AF had significantly higher rates of ischemic stroke than patients without HF without AF during follow-up (incidence rate ratio 1.91 [95% confidence interval 1.75-2.09], P < .001). Ischemic stroke rates remained significantly higher for patients with HF over time among individuals without AF (P < .001 for log-rank test at 12, 24, and 36 months). Similar results were found for the overall HF population. Conclusions: Even in the absence of AF, patients with HF are at heightened risk of ischemic stroke compared with patients without HF.