The Prognostic Significance of White Blood Cell and Platelet Count for In-hospital Mortality and Pneumonia in Acute Ischemic Stroke

Background: We investigated the combined effect of white blood cell (WBC) and platelet count on in-hospital mortality and pneumonia in acute ischemic stroke (AIS) patients. Methods: A total of 3,265 AIS patients enrolled from December 2013 to May 2014 across 22 hospitals in Suzhou city were included in the present study. We divided patients into four groups according to their level of WBC and platelet count: LWHP (low WBC and high platelet), LWLP (low WBC and low platelet), HWHP (high WBC and high platelet), and HWLP (high WBC and low platelet). A logistic regression model was used to estimate the combined effect of WBC and platelet counts on all-cause in-hospital mortality and pneumonia in AIS patients. Results: HWLP was associated with a 2.07-fold increase in the risk of in-hospital mortality in comparison to LWHP (adjusted odds ratio (OR) 2.07; 95% confidence interval (CI), 1.02-4.18; P-trend =0.020). The risk of pneumonia was significantly higher in patients with HWLP than those with LWHP (adjusted OR 2.29; 95% CI, 1.57-3.35; P-trend <0.001). The C-statistic for the combined WBC and platelet count was higher than WBC count or platelet count alone for the prediction of in-hospitalmortality and pneumonia (all P < 0.01). Conclusion: High WBC count combined with a low platelet count level at admission was independently associated with in-hospital mortality and pneumonia in AIS patients. Moreover, the combination of WBC count and platelet count level appeared to be a better predictor than WBC count or platelet count alone.