Interrupted Time-Series for the Evaluation of Affordable Care Act Impact on Stereotactic Radiosurgery for the Treatment of Brain Metastases

Abstract Background: The 2010 Affordable Care Act aimed at reducing healthcare costs, improving healthcare quality and expanding health insurance coverage among uninsured individuals in the United States. We examined trends in utilization of radiation therapies and stereotactic radiosurgery before and after its implementation among U.S. adults hospitalized with brain metastasis.Methods: Interrupted time-series analyses of data on 383934 2005-2014 Nationwide Inpatient Sample hospitalizations were performed, whereby yearly and quarterly cross-sectional data were evaluated and Affordable Care Act implementation was considered the main exposure variable, stratifying by patient and hospital characteristics. Results: We observed consistently declining trends in radiation therapy over time and post-Affordable Care Act status with variability in level of utilization among specific sub-groups. Stereotactic radiosurgery prevalence increased over time among Hispanics, elective admissions, Midwestern hospitals, non-teaching hospitals and hospitals with medium bed size. Post-Affordable Care Act was associated with increased stereotactic radiosurgery prevalence among African-Americans, non-elective and weekend admissions, with changes in slope in the context of weekend admissions and hospitals with large bed size. Conclusions: Whereas hospitalized adults in the United States utilized less radiation therapy and slightly more stereotactic radiosurgery over the ten-year period, utilization levels and trends were not consistent among distinct sub-groups defined by patient and hospital characteristics, with some traditionally underserved populations more likely to receive healthcare services post-Affordable Care Act implementation. The Affordable Care Act may be helpful at reducing the need for radiation therapy and closing the gap in access to technological advances such as stereotactic radiosurgery for treating brain metastases.