Abstract 124: Pre-Stroke Aspirin Use Does Not Impact Small Subcortical Stroke Size: A Secondary Analysis of the SPS3 Trial

Abstract

Introduction: The use of pre-stroke aspirin is associated with smaller stroke size in first-time stroke related to large vessel occlusion. However, it is unknown whether pre-stroke aspirin use impacts stroke size for an acute small subcortical infarct (SSI). We hypothesized that pre-stroke aspirin use would be associated with a smaller sized SSI. Methods: We performed a secondary analysis of the Secondary Prevention of Small Subcortical Strokes (SPS3) dataset which enrolled between 2003 and 2007. We included participants ≥ 55 years old with brain-MRI confirmed SSI being ≤ 20 mm in maximal diameter on diffusion weighted imaging. Stroke size was determined retrospectively by the study team on the index event brain MRI. Pre-stroke medications were recorded at the time of enrollment. Chi-squared and student’s T test were used for categorical and continuous variables, respectively. Binary logistic regression models were fitted for likelihood ratios. Results: Of the 3020 participants enrolled in SPS3, a total of 2183 met inclusion criteria: 663 with pre-stroke aspirin monotherapy and 1520 without pre-stroke antithrombotic use, Table 1. Those with aspirin use were older with a higher incidence of diagnoses of hypertension, hyperlipidemia, and diabetes mellitus, though otherwise sex, and tobacco use did not differ. The mean maximal stroke width, trended towards, but was not statistically impacted by pre-stroke aspirin use [pre-stroke aspirin: 11.8 (4.1) mm vs 11.4 (4.1) mm, p =0.065]. After adjustment for significant variables, pre-stroke aspirin use did not impact the odds of a larger infarct size (OR 0.779, 95%CI 0.615-1.04, p =0.092). Conclusion: Despite those with pre-stroke aspirin use having more vascular risk factors, its use did not impact stroke size amongst those with an acute SSI enrolled in the SPS3 trial.