PAI-1 4G/5G Polymorphism is Associated with Brain Vessel Reocclusion After Successful Fibrinolytic Therapy in Ischemic Stroke Patients

Background: Despite t-PA proven benefits related to vessel reopening, up to 13% of stroke patients suffer reocclusions after t-PA. We aimed to analyze whether a functional polymorphism in a fibrinolysis inhibitor gene [plasminogen activator inhibitor-1 (PAI-1)] might be associated with reocclusion rates after stroke thrombolytic therapy. Methods: 165 patients with ischemic stroke who received t-PA < 3 h were studied. Reocclusion and recanalization was diagnosed by transcranial Doppler. PAI-1 4G/5G polymorphism determination was performed by sequencing. PAI-1 mRNA was studied by real-time PCR analysis. National institutes of health stroke scale (NIHSS) was serially measured since patients arrival to assess the neurological outcome, and modified ranking scale (mRS) at 3rd month was used to evaluate functional outcome following stroke. Results: PAI-1 4G/4G patients had higher reocclusion rates (4G/4G = 12.5% versus other genotypes = 2.7%, p = 0.025). . In a logistic regression, the 4G/4G genotype was the only factor associated with reocclusion (OR = 15.16 95%, CI = 1.4-163.4, p = 0.025). 4G/4G genotype was also associated with poor functional outcome at 3rd month (4G/4G = 4 versus others genotypes = 3, p = 0.017) and with mRNA levels at 12 h post stroke symptoms onset (4G/4G patients = 2.01% versus other genotypes = 0.68%, p = 0.034). Conclusions: PAI-1 4G/4G genotype is associated with reocclusion rates and poor functional outcome among stroke patients treated with t-PA.