Impact of onset-to-reperfusion time on stroke mortality: a collaborative pooled analysis

Abstract

Background: Onset-to-reperfusion time has been reported to be associated with clinical prognosis. However, its impact on mortality remained to be assessed. Using a collaborative pooled analysis, we examined whether early mortality after successful endovascular treatment is time dependent.

Methods and results: In a collaborative pooled analysis of 7 endovascular databases, we assessed the impact of onset-to-reperfusion time in large-artery occlusion (internal carotid artery or middle cerebral artery) on outcomes. Successful reperfusion was defined as complete or partial restoration of blood flow within 8 hours from symptom onset. Primary outcome was 90-day all-cause mortality. Secondary outcomes included 90-day favorable outcome (modified Rankin Scale score, 0-2), 90-day excellent outcome (modified Rankin Scale score, 0-1), and occurrence of any intracerebral hemorrhage within 24 to 36 hours after treatment. A total of 480 cases with successful reperfusion (median time, 285 minutes) contributed to the present pooled analysis (120 with internal carotid artery occlusion and 360 with isolated middle cerebral artery occlusion). Increasing onset-to-reperfusion time was associated with an increased rate of mortality and intracerebral hemorrhage and with a decreased rate of favorable and excellent outcomes, without heterogeneity across studies. The adjusted odds ratio for each 30-minute time increase was 1.21 (95% confidence interval, 1.09-1.34; P<0.001) for mortality, 0.79 (95% confidence interval, 0.72-0.87) for favorable outcome, 0.78 (95% confidence interval, 0.71-0.86) for excellent outcome, and 1.21 (95% confidence interval, 1.10-1.33) for intracerebral hemorrhage.

Conclusion: Onset-to-reperfusion time affects mortality and favorable outcome and should be considered the main goal in acute stroke patient management.

Keywords: meta-analysis; stroke; stroke reperfusion injury.