Association of Admission Leukocyte Count with Clinical Outcomes in Acute Ischemic Stroke Patients Undergoing Intravenous Thrombolysis with Recombinant Tissue Plasminogen Activator

Objective An increased leukocyte count is positively associated with poor outcomes and all-cause mortality in coronary heart disease, cancer, and ischemic stroke. The role of leukocyte count in acute ischemic stroke (AIS) remains important. We aimed to investigate the association between admission leukocyte count before thrombolysis with recombinant tissue plasminogen activator (rt-PA) and 3-month outcomes in AIS patients. Methods This retrospective study included consecutive AIS patients who received intravenous (IV) rt-PA within 4.5 h of symptom onset between January 2016 to December 2018. We assessed outcomes, including short-term hemorrhagic transformation (HT), 3-month mortality, and functional independence (modified Rankin Scale [mRS] score of 0-2 or 0-1). Results Among 579 patients who received IV rt-PA, 77 (13.3%) exhibited HT at 24 h, 43 (7.4%) died within 3 months, and 211 (36.4%) exhibited functional independence (mRS score: 0-2). Multivariable logistic regression revealed admission leukocyte count as an independent predictor of good and excellent outcomes at 3 months. Each 1-point increase in admission leukocyte count increased the odds of poor outcomes at 3 months by 7.6% (mRS score: 3-6, odds ratio [OR]: 1.076, 95% confidence interval [CI]: 1.003-1.154, p=0.041) and 7.8% (mRS score: 2-6, OR: 1.078, 95% CI: 1.006-1.154, p=0.033). Multivariable regression analysis revealed no association between HT and 3-month mortality. Admission neutrophil and lymphocyte count were not associated with 3-- month functional outcomes or 3-month mortality. Conclusion A lower admission leukocyte count independently predicts good and excellent outcomes at 3 months in AIS patients undergoing rt-PA treatment.