Trends of Ruptured and Unruptured Aneurysms Treatment in the United States in Post‐ISAT Era: A National Inpatient Sample Analysis

Abstract

Background The ISAT (International Subarachnoid Aneurysm Trial) has generated a paradigm shift towards endovascular treatment for intracranial aneurysms but remains unclear if this has led to a true reduction in the risk for aneurysmal subarachnoid hemorrhage (aSAH). We sought to study the association between the treatment burden of unruptured and ruptured aneurysms in the post‐ISAT era. Methods and Results Admissions data from the National Inpatient Sample (2004–2014) were extracted, including patients with a primary diagnosis of aSAH or unruptured intracranial aneurysms treated by clipping or coiling. Within each year, this combined group was randomly matched to non‐aneurysmal control group, based on age, sex, and Elixhauser comorbidity index. Multinomial regression was performed to calculate the relative risk ratio of undergoing treatment for either ruptured or unruptured aneurysms in comparison with the reference control group, adjusted for time. After adjusting for National Inpatient Sample sampling effects, 243 754 patients with aneurysm were identified, 174 580 (71.6%) were women; mean age, 55.4±13.2 years. A total of 121 882 (50.01%) patients were treated for unruptured aneurysms, 79 627 (65.3%) endovascularly and 42 256 (34.7%) surgically. A total of 121 872 (49.99%) patients underwent procedures for aSAH, 68 921 (56.6%) endovascular, and 52 951 (43.5%) surgically. Multinomial regression revealed a significant year‐to‐year decrease in aSAH procedures compared with the control group of non‐aneurysmal hospitalizations (relative risk ratio, 0.963 per year; P <0.001), while there was no statistical significance for unruptured aneurysms procedures (relative risk ratio, 1.012 per year; P =0.35). Conclusions With each passing year, there is a significant decrease in relative risk ratio of undergoing treatment for aSAH, concomitant with a stable annual risk of undergoing treatment for unruptured intracranial aneurysms.

Comparison of outcomes between a ruptured and unruptured intracranial aneurysm: results from an Indonesian cohort study

“…Although direct causality cannot be ascertained, they suggested that this decrease was the result of pre-emptive treatment of high-risk unruptured intracranial aneurysms. 16 This data showed the benefit of performing screening in selected individuals with a high risk for intracranial aneurysm. Regarding treatment modalities, since the publication of the International Subarachnoid Aneurysm Trial (ISAT), there has been an increase in the number of coiling procedures.…”

“…Studies from the United States of America and Korea reported that the number of coiling performed for either unruptured or ruptured intracranial aneurysm has increased substantially, overtaking clipping as the most performed procedure for treating aneurysm. 16,17 Our study has several limitations. The retrospective and single-center designs have an inherent risk of confounding bias.…”

Microsurgery for intracranial aneurysms: A qualitative survey on technical challenges and technological solutions

“…In the United Kingdom, the overwhelming majority of aneurysms are clipped by subspecialist neurovascular surgeons but in an environment that has some important differences compared with the large United States centres that feature prominently in the literature. For example, resources are significantly more constrained with 50% lower healthcare expenditure per capita ( 43 ), it is much less common for neurovascular surgeons to be dual-trained, and the overall proportion of aneurysms treated endovascularly is higher ( 44 , 45 ).…”

Optimal Cost-Effective Screening Strategy for Unruptured Intracranial Aneurysms in Female Smokers

“…For the patients who were considered for treatment, endovascular (70%) or surgical (30%) treatment was used. 26…”