Efficacy and Safety of Thrombolytic Therapy for Stroke with Unknown Time of Onset: A Meta-Analysis of Observational Studies.

BACKGROUND

Recombinant tissue plasminogen activator (rt-PA) is one of the most effective therapies available for patients with known-onset stroke (KOS). Whether rt-PA treatment would improve functional outcomes in patients with stroke with unknown time of onset (UTOS) is undetermined, we aimed to systematically assess the efficacy and safety of thrombolysis for UTOS patients in this meta-analysis.

METHODS

A systematic literature search of Medline, Embase, and Cochrane Library was conducted. We considered the relevant data comparing thrombolyzed UTOS patients versus nonthrombolyzed UTOS patients or thrombolyzed UTOS patients versus thrombolyzed KOS patients. Treatment efficacy and safety were measured according to modified Rankin Scale scores of 0-2 (mRS 0-2), and the presence of spontaneous intracerebral hemorrhage (SICH) or mortality at 90 days respectively.

RESULTS

A total of 11 studies with 2581 patients meeting the inclusion criteria were included in the meta-analysis. All the patients had an ischemic lesion that was assessed by imaging including computed tomography or magnetic resonance imaging. Among these studies, 6 compared the thrombolytic efficacy in thrombolyzed UTOS patients with that in nonthrombolyzed UTOS patients (mRS 0-2: odds ratio [OR] =1.76, 95% confidence interval [CI] 1.11-2.81, P = .02), and 8 studies compared thrombolyzed UTOS patients with thrombolyzed KOS patients (mRS 0-2: OR = 0.87, 95% CI 0.66-1.15, P = .33). The incidence of SICH and mortality at 90 days had no difference between thrombolyzed UTOS patients versus nonthrombolyzed UTOS patients and thrombolyzed UTOS patients versus thrombolyzed KOS patients (all P > .05).

CONCLUSIONS

Data from observational studies suggest that thrombolysis for UTOS patients had significantly favorable outcomes at 90 days compared with nonthrombolyzed patients.