Abstract WP35: Age-Stratified Outcomes After Mechanical Thrombectomy for Large Vessel Occlusion

Abstract

Introduction: Mechanical thrombectomy (MT) has become a significant component in the management of acute ischemic stroke (AIS). The majority of randomized trials establishing the safety and efficacy of MT in AIS have excluded elderly patients above 80 years old. In this work, we assessed the safety and efficacy of MT in different age groups with a focus on how elderly patients respond compared to their younger counterparts. Methods: We retrospectively reviewed a database of AIS cases that underwent MT for large vessel occlusions at the Medical University of South Carolina between 01/13 and 03/17. Patients were categorized into 4 age-groups (<80, 80-85, 85-90, and ≥90 years), and baseline characteristics, procedural variables, and 90-day outcomes were compared across the age groups. Results: A total of 436 AIS patients (50.2% women, mean age 67.3 years) underwent MT during the study period. Patients in the elderly groups (80-85, 85-90, ≥90) included significantly more females and had a higher NIHSS at baseline compared to younger patients (<80, p<0.01). There were no significant differences in time from onset to treatment, rate of IV or IA tPA, and procedural variables including time to recanalization, final TICI flow, and the number of devices or attempts (p>0.05). There were also no significant differences in the rates of hemorrhagic and other complications across the four groups (p>0.05). Modified Rankin scores (mRS) at 90 days were significantly higher in the 3 elderly groups compared to younger patients (p<0.001), and the likelihood of good outcomes (mRS 0—2) dropped from 50% in the <80 years group to 18.3%, 17.4% and 7.7% in the 80-85, 85-90 and ≥90 groups respectively. A similar and significant trend was seen with 90-day survival that decreased from 85% in the <80 years group to 75%, 59% and 33% in the 80-85, 85-90 and ≥90 groups respectively (p<0.001). We then used multivariate logistic regression analysis to show that age above 80 years is an independent predictor of mortality and vegetative state at 90 days (OR=2.6, p=0.003). Conclusions: Our findings suggest that elderly patients above 80 years old are less likely to benefit from MT after AIS compared to younger patients despite not being at a higher risk of immediate complications or post-procedural hemorrhage.