Acute Symptomatic Seizure Associated With Chronic Antiseizure Medication Use After Stroke.

Background and Objective: Patients with acute symptomatic seizures (ASyS) after stroke are discharged on antiseizure medications (ASMs) and stay on them for an extended period. We analyzed the current ASM management practice, 6 months, and at the last follow-up after stroke-related ASyS concerns to identify chronic and long-term ASM use predictors. Methods: A single-center, retrospective cohort study of adults who underwent continuous EEG monitoring for ASyS concerns after stroke (April 1, 2012 to March 31, 2018) with at least 6 months of follow-up was performed. ASM use beyond 6 months after the initial ASyS concern was defined as "chronic" among patients discharged on them. "Long-term" ASM use at the last follow-up in all patients with ASyS concerns was analyzed. Logistic regression and Cox regression multivariable modeling to analyze predictors of "chronic" and "long-term" ASM use, respectively, was performed. Results: A total of 465 (mean age 61.7 ± 13.3 years and 52% female patients) patients (41.9% ischemic stroke, 36.1% intracerebral hemorrhage, and 21.9% subarachnoid hemorrhage) were included. Of the 179 (38.5%) patients discharged on ASMs, 132 (73.7%; 28.4% of study population) had chronic ASM use, despite 90% not experiencing any seizure (poststroke epilepsy [PSE]) during this time. The independent predictors of chronic ASM use were electrographic ASyS (odds ratio [OR] = 9.27, 95% CI = 2.53-60.4) and female sex (OR = 2.2, 95% CI = 1.02-4.83). After a median 61-month (5.1 years) follow-up, 101 (21.7%) patients in the study population were on long-term ASM use, including 67 (14.4%) who developed PSE. Long-term ASM use was associated with NIH Stroke Scale Score (OR = 1.5, 95% CI = 1.015-1.98), cortical involvement (OR = 1.28, 95% CI = 1.02-1.6), convulsive ASyS (OR = 1.46, 95% CI = 1.02-2.09), epileptiform findings on outpatient EEG (OR = 4.03, 95% CI = 1.28-12.76), and PSE development (OR = 7.06, 95% CI = 3.7-13.4). Discussion: Chronic ASM use is highly associated with electrographic, rather than convulsive, ASyS. However, long-term ASM use is independently associated with PSE and its risk factors, including convulsive ASyS. With the ubiquity of stroke-related ASyS concerns in routine clinical practice, comparative effectiveness studies to guide ASM management are needed.