Abstract
OBJECTIVE: To investigate the prognostic value of white blood cell count (WBC) on functional outcome, mortality and bleeding risk in stroke patients treated with intravenous thrombolysis (IVT). METHODS: In this prospective multicenter study from the TRISP registry, we assessed the association between WBC on admission and 3-month poor outcome (modified Rankin Scale 3-6), mortality and occurrence of symptomatic intracranial hemorrhage (sICH; ECASS-II-criteria) in IVT-treated stroke patients. WBC was used as continuous and categorical variable distinguishing leukocytosis (WBC > 10 × 10(9)/l) and leukopenia (WBC < 4 × 10(9)/l). We calculated unadjusted/ adjusted odds ratios with 95% confidence intervals (OR [95% CI]) with logistic regression models. In a subgroup, we analyzed the association of combined leukocytosis and elevated C-reactive protein (CRP > 10 mg/l) on outcomes. RESULTS: Of 10,813 IVT-treated patients, 2527 had leukocytosis, 112 leukopenia and 8174 normal WBC. Increasing WBC (by 1 × 10(9)/l) predicted poor outcome (OR(adjusted) 1.04[1.02-1.06]) but not mortality and sICH. Leukocytosis was independently associated with poor outcome (OR(adjusted) 1.48[1.29-1.69]) and mortality (OR(adjusted) 1.60[1.35-1.89]) but not with sICH (OR(adjusted) 1.17[0.94-1.45]). Leukopenia did not predict any outcome. In a subgroup, combined leukocytosis and elevated CRP had the strongest association with poor outcome (OR(adjusted) 2.26[1.76-2.91]) and mortality (OR(adjusted) 2.43[1.86-3.16]) when compared to combined normal WBC and CRP. CONCLUSION: In IVT-treated patients, leukocytosis independently predicted poor functional outcome and death. Bleeding complications after IVT were not independently associated with leukocytosis.