Decline in Hemoglobin during Hospitalization May Be Associated with Poor Outcome in Acute Stroke Patients

Abstract

Background and purpose: Anemia upon hospital admission is a known predictor of poor functional outcomes in patients with acute cerebral infarction. However, it remains unclear whether reductions in hemoglobin levels during hospitalization influence stroke outcomes. We investigated the association between in-hospital decline in hemoglobin and poor outcomes.

Materials and methods: We retrospectively analyzed data from 480 consecutive patients who had experienced acute cerebral infarction and presented without anemia between January 2012 and March 2015. Decline in hemoglobin was taken as the difference between hemoglobin levels upon admission and nadir hemoglobin. Poor outcome was defined as a modified Rankin Scale score 3-6. A multivariate analysis of the relationship between decline in hemoglobin and poor outcome at discharge was conducted for various patient characteristics.

Results: The mean hemoglobin level at admission was 14.3 ± 1.3 g/dL, whereas the mean nadir hemoglobin value was 13.1 ± 1.9 g/dL, with a mean decline in hemoglobin of 1.3 ± 1.5 g/dL. In patients with poor outcomes, mean decline in hemoglobin was significantly reduced to 3.1 g/dL (P < .001). The optimal cutoff decline in hemoglobin required to distinguish a poor outcome was 1.5 g/dL whereas the sensitivity and specificity were 62% and 82.3%, respectively, with an area under the curve of .77 (P < .0001). A decline in hemoglobin below 1.5 g/dL was found to be an independent predictor of poor outcome (odds ratio: 2.10; confidence interval: 1.10-3.99; P = .023).

Conclusion: Decline in hemoglobin in patients hospitalized with acute stroke may be associated with poor outcome.

Keywords: Stroke; anemia; cerebral infarction; functional outcome; hemoglobin.