Abstract WP238: Efficacy of Dual Antiplatelet Therapy After Lacunar versus Non-Lacunar Syndromes in the POINT Trial

Abstract

Introduction: About 20% of ischemic strokes are lacunar infarcts, the pathophysiology of which differs from that of other stroke etiological subtypes. The POINT trial demonstrated the efficacy of dual antiplatelet therapy (DAPT) for secondary stroke prevention in patients with minor ischemic stroke and high-risk TIA, but it remains unknown whether this benefit differed in lacunar versus non-lacunar strokes. Method: In a secondary analysis of POINT trial data, we compared the efficacy of DAPT in patients with an index lacunar syndrome versus not. A lacunar syndrome was defined based on common classic lacunar syndromes (e.g., pure motor hemiparesis, clumsy-hand dysarthria) and ascertained using subcomponents of the National Institutes of Health Stroke Scale documented at baseline. Our primary efficacy outcome was ischemic stroke and the safety outcome was intracranial hemorrhage. We used survival analysis and tests of interaction to compare the effect of DAPT between the lacunar and non-lacunar subgroups. Result: Among 4,881 patients enrolled in the study, 1,083 (22.1%) were classified as having an index lacunar syndrome. The effect of DAPT on the risk of ischemic stroke did not vary significantly after a lacunar syndrome (HR, 0.76; 95% CI, 0.52-1.09) versus after a non-lacunar syndrome (HR, 0.69; 95% CI, 0.50-0.95) (P value for interaction, 0.70). Similarly, the effect of DAPT on the risk of intracranial hemorrhage did not vary significantly after a lacunar syndrome (HR, 2.82; 95% CI, 0.29-27.1) versus after a non-lacunar syndrome (HR, 2.10; 95% CI, 0.63-6.99) (P for interaction, 0.82). Conclusion: In a post hoc secondary analysis of the POINT trial, we found no evidence of a lesser benefit of DAPT after a minor ischemic stroke or TIA in patients presenting with a lacunar syndrome compared to other stroke subtypes.