Red cell distribution width and outcome in acute ischemic stroke patients

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 AIS.

Methods

Patients with AIS were divided in four groups according to the quartile of 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 (dichotomized as independent [0-2] or dependent [>2] according to the modified Rankin Scale score) 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). Univariate analysis showed a negative association between RDW-Q4 and independence at 3 months (p=0.024), which wasn't verified in the multivariate analysis (p=0.871). Univariate analysis also identified a positive association between RDW-Q4 and 90-day mortality (p=0.049), which was not confirmed in the multivariate analysis (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.