Association of Short-Course Methylprednisolone Therapy With Early Composite Imaging Abnormalities in Patients With Early Neurological Deterioration After Endovascular Thrombectomy for Acute Ischemic Stroke.

Abstract

Background: Early neurological deterioration (END) after endovascular thrombectomy (EVT) may be accompanied by heterogeneous postprocedural imaging abnormalities. We investigated the association between short-course methylprednisolone and a study-defined early composite imaging abnormality after EVT.

Methods: This single-center retrospective analysis included 297 patients with acute ischemic stroke who developed END within 72 hours after EVT (96 treated with methylprednisolone and 201 not treated). The index time was defined as completion of the post-END treatment decision, and the first intravenous methylprednisolone dose marked the onset of exposure. The first evaluable scan obtained after END confirmation but before completion of the treatment decision was designated the index scan. All evaluable scans obtained after the index time through 72 hours after EVT were reviewed. For patients who met the primary composite outcome, the endpoint scan was the first scan showing a new abnormality or progression of a preexisting abnormality that met the specified progression criteria; for patients who did not meet the primary outcome, it was the last evaluable scan within 72 hours after EVT. Multivariate logistic regression, propensity-score analyses, a restricted analysis among patients with modified Thrombolysis in Cerebral Infarction (mTICI) grade 2b-3, and false discovery rate (FDR) correction were used.

Results: The composite outcome occurred in 42 of 96 treated patients and 122 of 201 untreated patients (43.8% vs 60.7%; p = 0.006). After multivariate adjustment, short-course methylprednisolone was associated with lower odds of the composite outcome (adjusted odds ratio, 0.46; 95% confidence interval [CI], 0.27-0.80; p = 0.005). The results were directionally consistent among patients with mTICI grades 2b-3 (adjusted odds ratio, 0.48; 95% CI, 0.27-0.86; p = 0.013), whereas the estimate for mTICI grades 0-2a was imprecise (p = 0.699). The index-to-endpoint-scan interval, endpoint imaging modality, and post-index scan frequency were comparable between groups. After FDR correction across 17 exploratory outcomes, only new or worsening cerebral edema remained statistically significant (q = 0.034). Neither the 90-day 3-category modified Rankin Scale (mRS) distribution nor the comparison of mRS 0-2 remained statistically significant after correction. Safety estimates were imprecise.

Conclusions: Short-course methylprednisolone was associated with lower odds of the study-defined early post-EVT composite imaging abnormality, primarily reflecting edema-related findings. This observational association did not establish functional benefit and requires prospective confirmation.