Acute ischaemic stroke outcomes following mechanical thrombectomy in the elderly versus their younger counterpart: a retrospective cohort study

OBJECTIVES Many physicians debate the efficacy of mechanical thrombectomy for ischaemic stroke, but most agree that to establish potential benefit, patient selection must be examined further. People >80 years are a growing population of patients with ischaemic stroke but are largely excluded from clinical trials. The benefit of thrombectomy for them may be greatly reduced due to diminishing neuroplasticity and a larger number of medical comorbidities. To address this knowledge gap, we examined clinical and economic outcomes after mechanical thrombectomy in the ischaemic stroke population from the Nationwide Inpatient Sample. Our null hypotheses were that elderly patients (>80 years) would have a similar rate of inpatient mortality in comparison to their younger counterparts and incur a similar economic expense. DESIGN Retrospective cohort study. SETTING A 20% stratified sample of US community hospitals within the Nationwide Inpatient Sample. PARTICIPANTS All patients from 2008 to 2010 with a primary diagnosis of ischaemic stroke that received mechanical thrombectomy were included. PRIMARY AND SECONDARY OUTCOME MEASURES The primary outcome was inpatient mortality. Secondary outcomes included hospital charges and length of stay. RESULTS Less than 1% of all ischaemic stroke cases (9300) were treated with mechanical thrombectomy. Of these, 18% involved patients over 80 years of age. The odds of inpatient mortality in elderly patients treated with mechanical thrombectomy were approximately twice that of their younger counterparts (OR1.993, p < 0.001). The elderly experienced no significant difference in hospital charges (p=0.105) and length of stay (p=0.498). CONCLUSIONS The odds of inpatient mortality after mechanical thrombectomy in patients over 80 years of age were twice that of their younger counterparts. This is consistent with the overall worse prognosis seen in the natural history of this age group. Studies to better identify patients that would benefit from endovascular mechanical thrombectomy may improve outcomes and reduce the gap currently observed in age stratifications.