Functional Outcomes at 90 Days in Octogenarians Undergoing Thrombectomy for Acute Ischemic Stroke: A Prospective Cohort Study and Meta-Analysis

Background: Elderly patients account for 30% of acute ischemic stroke (AIS) but are under-represented in randomized controlled trials of endovascular thrombectomy (EVT). Meta-analysis of “real world” studies evaluating 90-day outcomes in elderly patients ≥80 years have been limited to small numbers undergoing EVT with older generation devices. Methods: A retrospective analysis of 181 prospectively collected patients who received EVT for anterior circulation AIS at an Australian center over 2.5-years. The study aims to determine (i) 90-day functional outcomes (modified Rankin Scale mRS 0–2) in patients ≥80 vs. <80 years, (ii) the interaction of prognostic factors and age and (iii) compare our data to those previously reported using a meta-analysis of outcomes in observational studies using second generation thrombectomy devices. Results: We analyzed 2,387 patients (≥80 years, n = 649; <80 years, n = 1,738) from 14 studies including our study (≥80 years, n = 71; <80 years, n = 110). Twenty-eight percent of our and 30% of the meta-analysis elderly cohort achieved good 90-day mRS compared to 55 and 52%, respectively of younger patients (p < 0.001). Twenty-seven percent of our and 26% of the meta-analysis elderly cohort died compared to 16% (p = 0.07) and 15% (p < 0.0001), respectively of younger patients. Baseline NIHSS≥16 correlated with poor prognosis in elderly (OR 16.4; 95% CI 4.49–59.91, p < 0.001) and younger (OR 8.73;95% CI 3.35–22.80, p < 0.001) patients. Prior rt-PA was associated with favorable outcome in younger (OR 2.90; 95%CI 1.29–6.52, p = 0.01) patients only. Conclusion: EVT has less favorable outcomes in elderly patients. However, results are better than outcomes in historical controls not treated with thrombectomy providing further support for EVT in the elderly.