Related Experiment Video
Updated: Apr 20, 2026
Estimating Bilateral Atrial Function by Cardiovascular Magnetic Resonance Feature Tracking in Patients with Paroxysmal Atrial Fibrillation
Published on: July 20, 2022
The association between red cell distribution width and stroke in patients with atrial fibrillation
Walid Saliba1, Ofra Barnett-Griness2, Mazen Elias3
1Department of Community Medicine and Epidemiology, Carmel Medical Center, Clalit Health Services, and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel; Internal Medicine C, Ha'emek Medical Center, Afula, Israel.
Insights
Red cell distribution width (RDW) is linked to higher stroke risk in atrial fibrillation patients. Higher RDW levels significantly predict stroke, even without anemia, improving risk assessment.
Area of Science:
- Cardiology
- Neurology
- Hematology
Background:
- Red cell distribution width (RDW) is a known predictor of cardiovascular morbidity and mortality.
- Atrial fibrillation (AF) is a major risk factor for ischemic stroke.
Purpose of the Study:
- To investigate the association between RDW and stroke risk in patients diagnosed with atrial fibrillation.
- To determine if RDW improves stroke risk prediction in AF patients.
Main Methods:
- A cohort of 41,140 adult patients with atrial fibrillation, not on anticoagulants, was identified from a large Israeli Health Maintenance Organization database.
- Patients were followed for the occurrence of stroke from diagnosis until December 31, 2012.
- Multivariate analysis adjusted for CHADS2 score risk factors was performed.
Main Results:
- A total of 1692 strokes occurred during follow-up. Stroke incidence increased progressively across RDW quartiles.
- Elevated RDW (>14.5%) was independently associated with a 29% increased hazard ratio for stroke (HR, 1.29).
- RDW inclusion improved the predictive model's accuracy (AUC 0.618 vs. 0.598 for CHADS2 alone).
Conclusions:
- Red cell distribution width is a significant, independent predictor of stroke in patients with atrial fibrillation.
- RDW improves the predictive accuracy of stroke risk in AF patients, regardless of anemia status.
- RDW offers valuable prognostic information for stroke risk stratification in AF.
Objective:
Red cell distribution width is associated with increased risk of cardiovascular morbidity and mortality. We aimed to assess its association with stroke in patients with atrial fibrillation.
Methods:
By using the computerized database of the largest Health Maintenance Organization in Israel, we identified a cohort of adults with atrial fibrillation diagnosed before January 1, 2012. Eligible subjects were not taking anticoagulants at baseline and had at least 1 blood cell count performed in 2011 (41,140 subjects). The cohort was followed for the first occurrence of stroke until December 31, 2012.
Results:
Overall, 1692 subjects developed stroke during 38,024 person-years of follow-up (stroke rate, 4.45 per 100 person-years). Stroke incidence rate increased across red cell distribution width quartiles: 3.26, 3.71, 5.01, and 6.05 per 100 person-years in the lowest (≤ 13.4%), second (13.4%-14.1%), third (14.1%-15.0%), and highest (>15%) red cell distribution width quartiles, respectively. On multivariate analysis adjusting for Congestive heart failure, Hypertension, Age ≥ 75, Diabetes, and Prior Stroke or TIA (doubled) (CHADS2) score risk factors, the hazard ratio for stroke was 1.29 (95% confidence interval, 1.17-1.42) in subjects with red cell distribution width >14.5% compared with those with values ≤ 14.5% and was similar in subjects with and without anemia. When analyzed as quartiles, the hazard ratio for stroke was 1.33 (confidence interval, 1.15-1.53) in the highest quartile compared with the lowest quartile and was similar in subjects with and without anemia. The area under the receiver operating characteristic curve was 0.598 for (CHADS2) score and increased to 0.618 when red cell distribution width was included in the model (P < .001).
Conclusions:
Red cell distribution width is directly associated with the risk of stroke regardless of anemia status and improves the predictive accuracy for stroke in patients with atrial fibrillation.
