Association of age with 1-year outcome in patients with acute ischaemic stroke treated with thrombectomy: real-world analysis in 18 506 patients

BACKGROUND: To evaluate the association of age with long-term outcome after thrombectomy. METHODS: In a retrospective cohort study based on routine healthcare data from Germany between 2010 and 2018, we included 18 506 patients with acute ischaemic stroke treated with mechanical thrombectomy. Association between age and mortality, disability, and level of care at 1 year was assessed. RESULTS: The median age was 76 years, 36.3% were aged ≥80 years and 55.8% were women. Patients aged ≥80 compared with those <80 years had a higher mortality (55.4% vs 28.5%; adjusted HR 1.13; 95% CI 1.05 to 1.31), more often had moderate/severe disability (35.5% vs 33.2%, adjusted HR 1.14; 95% CI 1.06 to 1.23) and less frequently had no/slight disability (17.4% vs 41.0%) at 1 year. Older age was associated with a higher likelihood of living in a nursing home (13.4% vs 9.2%, adjusted HR 1.09; 95% CI 0.97 to 1.22) and a lower likelihood of living at home (33.8% vs 62.8%) at 1 year. These associations were also robust when analysed in patients with no disability prior to stroke. Factors most strongly associated with worse 1-year outcomes in elderly patients were chronic limb-threatening ischaemia (67.9% vs 56.4%; HR 1.59, 95% CI 1.38 to 1.82), dementia at baseline (65.2% vs 47.3%; HR 1.29, 95% CI 1.17 to 1.44) and ventilation >48 hours (79.3% vs 52.2%; HR 2.91, 95% CI 2.66 to 3.18). CONCLUSIONS: In this large ‘real-world’ cohort, outcomes after mechanical thrombectomy were strongly associated with age. Of patients aged ≥80 years more than half were dead and less than one-fifth were functionally independent at 1 year. Certain comorbidities and ventilation >48 hours were associated with even worse outcomes.