Predictive outcome models in ischemic stroke: Comparison of Latin American Stroke Registry and RESILIENT against models

Abstract Introduction Despite the significant stroke burden in the region, the RESILIENT trial remains the only randomized controlled trial (RCT) for stroke treatment in Latin America. Imbalances in baseline factors typically hamper comparisons between stroke populations. The Latin American Stroke Registry (LASE) is a registry of patients receiving tPA and thrombectomy from 17 centers across 9 countries. We compared the outcomes of LASE and RESILIENT at each cohort’s baseline characteristics against models derived from other RCTs. Methods A systematic search identified RCTs that provided median NIHSS, mean age, percentage of patients receiving tPA, time-to-randomization, 90-day mRS0-2, and mortality. Akaike Information Criterion (AIC) was used to select the best model amongst 31 combinations of 5 variables. 90-day outcomes of LASE and RESILIENT were compared at their baseline values against the selected model. Results 35 RCTs encompassing 8376 subjects were identified. Models based on baseline NIHSS and the percentage of intravenous thrombolysis (IVT) were considered the most optimum in terms of AIC. The LASE registry included 950 patients receiving IVT alone, 127 that received IVT and mechanical thrombectomy (MT), and 101 receiving only MT. LASE & RESILIENT outcomes were plotted onto the models at their baseline values. LASE IVT alone group outcomes were in line with the RCT-informed model. LASE MT alone and MT + IVT, and the RESILIENT MT arm (68.5% IVT) demonstrated superior efficacy compared to no-MT. The RESILIENT control arm (71.8% tPA) had higher-than-expected mortality, while mortality of all other arms was within the predicted range. Conclusion Functional outcomes and mortality of patients from the LASE and RESILIENT trial receiving MT and MT+IVT compared favorably to the 90-day functional and mortality outcomes predicted in a model derived from no-MT data from other stroke RCTs, indicating Latin American MT systems of care are comparable to those of more resourceful regions. Higher mortality from IVT in the RESILIENT trial requires further investigation.