Abstract TP142: Platelet Count And Intracerebral Hemorrhage Expansion In The ATACH 2 Trial

Abstract

Introduction: The effect of platelet count on hematoma expansion in patients with intracerebral hemorrhage (ICH) has not been sufficiently studied. We performed a secondary analysis of the ATACH 2 trial to examine the association between platelet count and hematoma expansion. Methods: We included patients with a baseline platelet count, volumetric measurement of ICH hematoma volume in mL on a baseline and 24-hour follow-up CT, and excluded those who had surgical evacuation in the first 24 hours. To address the right skew of ICH volume, the primary outcome was the log difference in ICH volume from baseline to 24-hour follow-up. The exposure was baseline platelet count and secondary exposure was the mean of the baseline and a 24-hour platelet count value. We fit unadjusted linear regression models and models adjusted for patient age, sex, race/ethnicity, smoking, baseline ICH volume, GCS, ICH location/side, and randomization arm. Results: We included 945 patients in our primary analysis (mean age 62.3, 62% male, 22.7% white, 57.1% Asian). The mean baseline platelet count was 220.7±61.9 with a standard distribution (Figure 1). There was no association between log difference in ICH volume and baseline platelet count (unadjusted p value=0.616, adjusted p value=0.730) or the mean platelet count over 24 hours (unadjusted p value=0.509, adjusted p value=0.853). The relationships are shown graphically in Figure 2. Conclusion: In patients with supratentorial ICH enrolled in the ATACH-II trial, there was not a significant association between platelet count and hematoma expansion.