165 National Reduction in Cerebral Arteriovenous Malformation Treatment Correlated with Increased Rupture Incidence

Abstract

INTRODUCTION: In 2014 “A Randomized Trial of Unruptured Brain Arteriovenous Malformations” (ARUBA) concluded that medical management alone was superior to interventional therapy for adult patients with unruptured brain arteriovenous malformations (AVMs). METHODS: 154,297 weighted AVM admissions were identified in the United States from 2003 to 2017 in the National Inpatient Sample. Annual AVM intervention and rupture rates were computed and multivariable logistic regression assessed likelihood of AVM intervention pre- and post-ARUBA. Segmented regression identified significant change-points and fitted segmented linear models for annual intervention and rupture rates. Pearson and Spearman coefficients examined correlation between annual AVM intervention and rupture rates. RESULTS: For unruptured AVMs, intervention proportion and likelihood of receiving intervention decreased following ARUBA (28.1% to 22.3%, P < 0.0001; adjusted odds ratio 0.857, 95% CI 0.751-0.977, P = 0.02). Ruptured AVM admissions increased from 14.7% to 18.6% after ARUBA (P < 0.0001). Between 2003 and 2017, segmented linear regression identified one significant change-point in unruptured AVM intervention rate between 2014 and 2015. Average annual percent change for rupture incidence and intervention rate increased by 0.49% (P=0.0001) and decreased by 1.17% (P = 0.0001), respectively. Annual AVM intervention rates had a strong inverse correlation with annual AVM rupture incidence (Pearson coefficient = -0.82, P = 0.0002). In 2017, the annual AVM rupture rate (20.6%) surpassed the annual AVM intervention rate (19.7%) for the first time. CONCLUSION: Following ARUBA, the odds of intervention for unruptured AVMs have decreased while ruptured AVM incidence has increased. These findings are inversely correlated suggesting that less unruptured AVM treatments may lead to a substantial increase in AVM rupture incidence.