Using the Stroke-TPI to select acute stroke patients for rt-PA in the 3- to 6-hour window identified a treatment-favorable group with improved outcomes (44.0% vs 34.2% with placebo; P=0.005).
Observational
Yes
Does multivariable risk-benefit profiling using Stroke-TPI improve patient selection for rt-PA therapy in acute stroke within the 3- to 6-hour window?
Multivariable risk-benefit profiling using the Stroke-TPI can identify acute stroke patients who benefit from rt-PA therapy in the 3- to 6-hour window, distinguishing them from those who may be harmed.
Absolute Event Rate: 44% vs 34.2%
p-value: p=0.005
BACKGROUND AND PURPOSE: The Stroke-Thrombolytic Predictive Instrument (Stroke-TPI) uses multivariate equations to predict outcomes with and without thrombolysis. We sought to examine whether such a multivariate predictive instrument might be useful in selecting patients with a favorable risk-benefit treatment profile for therapy after 3 hours. METHODS: We explored outcomes in patients from 5 major randomized clinical trials testing intravenous recombinant tissue plasminogen activator (rt-PA) classified by the Stroke-TPI as "treatment-favorable" or "treatment-unfavorable." We used iterative bootstrap re-sampling to estimate how such a model would perform on independent test data. RESULTS: Among patients treated within the 3- to 6-hour window, 67% of patients were classified by Stroke-TPI predicted outcomes as "treatment-favorable" and 33% were classified as "treatment-unfavorable." Outcomes in the treatment-favorable group demonstrated benefit for thrombolysis (modified Rankin Scale score < or =1: 44.0% with rt-PA versus 34.2 with placebo, P=0.005), whereas harm was demonstrated in the treatment-unfavorable group (modified Rankin Scale score < or =1: 31.3% with rt-PA versus 38.3% with placebo; P=0.004). Bootstrap resampling with complete cross-validation showed that the absolute margin of benefit in the treatment-favorable group diminished on average by 36% between derivation and independent validation sets, but still represented a significant tripling of improvement in benefit compared with conventional inclusion criteria (5.2% interquartile range, 1.7% to 8.6% versus 1.8% interquartile range, -0.5 to 4.1, P<0.0001). CONCLUSIONS: Such multivariable risk-benefit profiling may be useful in the selection of acute stroke patients for rt-PA therapy even more than 3 hours after symptom onset. Prospective testing is indicated.
Kent et al. (Fri,) conducted a observational in Acute stroke. Intravenous recombinant tissue plasminogen activator (rt-PA) vs. Placebo was evaluated on Modified Rankin Scale score ≤1 in the treatment-favorable group (p=0.005). Using the Stroke-TPI to select acute stroke patients for rt-PA in the 3- to 6-hour window identified a treatment-favorable group with improved outcomes (44.0% vs 34.2% with placebo; P=0.005).