Abstract Body: Background: Endovascular therapy (EVT) has emerged as a first-line intervention for vertebrobasilar artery occlusion (VBAO) patients, supported by two recent landmark randomized controlled trials. However, EVT outcomes may vary based on patient age and collateral status. This study examines the interaction between age and collateral status on EVT outcomes in VBAO patients.
Methods: We retrospectively analyzed VBAO patients who underwent EVT from a prospectively maintained database between January 2014 and January 2024. Patients were categorized into non-octogenarians (age <80 years) and octogenarians (age ≥80 years). Collateral status was assessed using the BATMAN score, with ≥7 indicating favorable collaterals. Outcome measures included favorable functional outcomes (modified Rankin Scale [mRS] 0-3 at 90 days) and mortality within 90 days.
Results: The study cohort comprised 195 VBAO patients, including non-octogenarians (n=148) and octogenarians (n=47), with a median age of 69 years (IQR: 58-79). Males accounted for 54.9% of the cohort. Non-octogenarians achieved higher rates of favorable functional outcomes (mRS 0-3: 46.3% vs. 24.4%, p=0.01) and lower mortality (43.4% vs. 68.3%, p=0.005). After adjustment for baseline imbalances, age ≥80 years was independently associated with increased mortality (aOR 4.84, 95% CI [1.55-15.16], p=0.007) and poorer functional outcomes (aOR 0.20, 95% CI [0.06-0.71], p=0.01). In subgroup analysis based on collateral status, favorable BATMAN scores (≥7) were associated with better functional outcomes in non-octogenarians (mRS 0-3: 55.3% with BATMAN ≥7 vs. 41.6% with BATMAN <7) despite not reaching statistical significance (p=0.13). Non-octogenarians with favorable BATMAN scores also had a trend towards lower mortality (31.9% vs. 49.4%, p=0.05), although this did not reach statistical significance in adjusted analysis. Among octogenarians, BATMAN ≥7 did not significantly affect clinical outcomes (mRS 0-3: 18.8% vs. 28.0%, p=0.50; mortality: 68.8% vs. 68.0%, p=0.96), further confirmed in adjusted analyses.
Conclusion: While favorable collaterals (BATMAN ≥7) significantly mitigate adverse effects in younger patients, their impact is less evident in octogenarians possibly due to increased frailty. These findings highlight the importance of considering the interaction between age and collateral status when selecting VBAO patients for EVT. Further studies are needed to confirm these contentions.