Abstract TP269: Determining Differences in the Association Between Atrial Fibrillation and Ischemic Stroke Outcomes by Acute Therapy Received

Abstract

Introduction: Whether the association between atrial fibrillation (AF) and ischemic stroke (IS) outcomes differs by IS therapy is unknown. Hypothesis: AF IS patients will have a worse discharge NIH Stroke Scale (NIHSS) and 90-day modified Rankin Scale (mRS) scores than non-AF, with differences by IS therapy. Methods: We studied a cohort of AF and non-AF IS patients from Johns Hopkins (2020-2023) with IS characteristics and demographics who received acute IS therapy (intravenous tissue plasminogen activator (IVtPA), mechanical thrombectomy (MT), or both). Multivariable regression models were used to examine the association between AF and either NIHSS (continuous or dichotomized at the mean (5)) or mRS (ordinal) separately, with interaction terms for IS therapy as appropriate. Results: Of the 240 patients (mean age 67, 52.5% female, 56.2% Black), 26.2% received IVtPA, 45.8% MT, and 27.9% both. There was no association between AF and NIHSS (β 1.53, 95% CI 0.38-3.4) in the final model, but there were higher odds of an NIHSS > 5 among AF patients (OR 3.46, 95% CI 1.16-10.30). AF patients had an increased odds of a worse mRS (Ordinal OR 2.05, 95% CI 1.14-3.71), but not after adjustment (Ordinal OR 1.07, 95% CI 0.52-2.20). The association between AF and IS outcomes differed by IS therapy (Table 1). AF patients who did not receive MT had a worse NIHSS and higher odds of a one unit increase in mRS, compared to AF patients who received MT (p-interaction 0.07, 0.01 respectively). Conversely, AF patients who received IVtPA had a worse NIHSS, compared to those who did not receive IVtPA (p-interaction 0.07), with essentially no difference in the association between AF and mRS in the final model when considering IVtPA use (p-interaction 0.09). Conclusion: In this study, AF patients had a higher mRS and worse discharge NIHSS versus non-AF, with differences by treatment; not receiving MT was detrimental for AF patients while our found worse outcome with IVtPA may reflect AF-associated treatment delays.