Thrombocytopenia and In-hospital outcomes in patients with acute ischemic stroke undergoing intravenous thrombolysis: Findings from a nationwide registry study in China.

ABSTRACT

BACKGROUND AND OBJECTIVE: Our study aimed to evaluate the associations between platelet count (PC) and in-hospital outcomes for patients with stroke after rt-PA intravenous thrombolysis. METHODS: We identified patients who had been hospitalized with a primary diagnosis of stroke and had received rt-PA intravenous thrombolysis from June 2015 to July 2019 at participating hospitals in the Chinese Stroke Center Alliance. PC measured before intravenous thrombolysis was categorized into the following four groups severe thrombocytopenia (PC < 100 × 109/L), mild thrombocytopenia (100 ≤ PC < 150 × 109/L), normal PC (150 ≤ PC ≤ 450 × 109/L), and thrombocythemia (PC > 450 × 109/L). Outcomes were determined from clinical data collected during hospitalization. The primary clinical outcome was symptomatic intracranial hemorrhage (sICH). Secondary outcomes were mortality, bleeding events, gastrointestinal (GI) hemorrhage, and in-hospital stroke recurrence. We used multivariate logistic regression models to evaluate the associations between PC and outcomes. RESULTS: We included 44,882 individuals with a median age of 66 years, of whom 34.7 % were female, 951 (2.1 %) had severe thrombocytopenia, 7218 (16.1 %) had mild thrombocytopenia, 36,522 (81.4 %) had a normal PC, and 191 (0.4 %) had thrombocythemia. Both severe and mild thrombocytopenia groups had higher risks of bleeding events (adjusted OR 1.30; 95 % CI,1.01-1.67; p = 0.045; adjusted OR 1.32; 95 % CI,1.19-1.46; p < 0.001) and sICH (adjusted OR 1.48;95 % CI,1.13-1.94; p = 0.005; adjusted OR 1.43;95 % CI,1.27-1.60; p < 0.001) than the normal PC group. Patients with 100 ≤ PC < 150 × 109/L also had a higher risk of in-hospital stroke recurrence (adjusted OR 1.12; 95 % CI,1.02-1.22; p = 0.02). CONCLUSIONS: Intravenous thrombolysis brings a high risk of sICH given PC < 150 × 109/L, especially PC < 100 × 109/L. It indicated that PC < 100 × 109/L is a reasonable contraindication to thrombolysis.