Impact of insurance type on national variation in cost of endovascular treatment for unruptured cerebral aneurysms.

BACKGROUND Identifying drivers of nationwide variation in healthcare costs could help reduce overall cost. Endovascular treatment for unruptured cerebral aneurysms (ETUCR) is an elective neurointerventional procedure that allows for detailed analysis of cost variation. This study aimed to investigate the role of insurance type in cost variation of ETUCR. METHODS A retrospective analysis of patients undergoing ETUCR was done. Demographic and hospital data were obtained from the National Inpatient Sample 2012-2015. Multivariate analysis was done using a generalized linear model. Oaxaca-Blinder decomposition was performed to identify factors driving cost variation. RESULTS There was a significant difference in median cost ($25 331.82 vs $25 825.25, respectively, P<0.001) as well as length of stay (P<0.001) and complications (P<0.001) between patients with private insurance and Medicare. In multivariate analysis, insurance type was not predictive of increased cost. Among patients aged 65-75 years there was a higher median cost with private insurance compared to Medicare ($28 373.85 vs $25 558.25, respectively, P<0.001) but no difference in complications or length of stay. Oaxaca-Blinder decomposition showed higher marginal costs associated with private insurance patients at hospitals with greater endovascular operative volume (P=0.015). CONCLUSIONS In patients aged 65-75 years, private insurance is associated with higher costs compared to Medicare; however, insurance type is not predictive of increased cost in multivariate analysis. Differential treatment of private insurance and Medicare patients at hospitals with greater operative volume seems to influence this difference, likely due to differential reimbursement schemes that lead to weaker cost controls.