Red Cell Distribution Width and Outcome in Acute Ischemic Stroke Patients

Abstract

Introduction: Several biomarkers have proven prognostic value for acute ischemic stroke (AIS) patients. Red cell distribution width (RDW) has been associated with several diseases and all-cause mortality and suggested as an independent predictor of Ischemic Stroke severity and outcome. This study aimed to investigate RDW as an independent predictor of functional outcome and death in the 3 months following acute ischemic stroke. Methods: Patients with AIS were divided in four groups by the RDW value at admission. Baseline characteristics of patients in each RDW quartile were compared by Chi-square or Kruskal-Wallis tests, as applicable. We prospectively analyzed the patients for functional outcome in the 3 months following the event. Functional outcome, dividing patients in two groups (independent and dependent) by modified Rankin Scale (mRS) scores, and 90-day mortality was compared between the 4 groups. To conduct this evaluation, univariable and multivariable binary logistic regression analysis for functional independence and mortality at 3 months was conducted, considering the variables previously identified as potential confounders. Results: The study's final population was of 416 patients. The patients in higher RDW quartiles were older (p<0,001), had lower blood hemoglobin (p<0,001), higher C reactive protein levels (p=0,017), higher BNP values (p<0,001) and more frequently suffered from atrial fibrillation (p=0,015) and heart failure (p=0,004). Being in the highest RDW quartile (RDW-Q4) showed a negative association with independence at 3 months in the univariable analysis (p=0,024), which wasn't verified in the multivariable analysis (p=0,871). A positive association between RDW-Q4 and 90-day mortality was verified in the univariable analysis (p=0,049), which didn't happen when multivariable analysis was applied (p=0,289). Conclusions: When adjusted to potential confounders, RDW does not predict functional outcome or death in the 90 days after acute ischemic stroke.