Red cell distribution width is associated with all-cause mortality in patients with acute stroke: a retrospective analysis of a large clinical database

OBJECTIVES: This study aimed to evaluate the association between the red blood cell distribution width (RDW) and mortality in patients with stroke. METHODS: We conducted a retrospective cohort study on patients with stroke in the Medical Information Mart for Intensive Care Database III. Cox proportional hazards regression models were used to estimate hazard ratios of 30-day, 90-day, and 1-year mortality in relation to the RDW level. RESULTS: A total of 4134 patients were enrolled, including 2646 patients with ischemic stroke and 1668 with hemorrhagic stroke. After adjustment for potential confounders, the hazard ratio (95% confidence interval) of 30-day mortality for the second (RDW: 13.4%–14.3%) and third (>14.3%) tertiles was 1.15 (0.96, 1.37) and 1.40 (1.17, 1.68), respectively, compared with the reference group (<13.4%). A two-piecewise linear regression model was established and the inflection point of RDW was 16.7%. When RDW was >16.7%, an increase in RDW did not increase stroke mortality. CONCLUSIONS: The RDW is a prognostic factor of patients with stroke. This finding needs to be confirmed in future prospective studies.