Association of medicaid expansion of the Affordable Care Act with the stage at diagnosis and treatment of papillary thyroid cancer: A difference-in-differences analysis

Abstract

Background: The Affordable Care Act's (ACA) Medicaid expansion has increased insurance coverage and improved various cancer outcomes. Its impact in papillary thyroid cancer (PTC) remains unclear.

Methods: Non-elderly patients (40-64 years-old) with PTC living in low-income areas either in a 2014 expansion, or a non-expansion state were identified from the National Cancer Database between 2010 and 2016. Insurance coverage, stage at diagnosis, and RAI administration were analyzed using a difference-in-differences analysis.

Results: 10,644 patients were included. Compared with non-expansion states, the percentage of uninsured patients (adjusted-DD -2.6% [95%-CI -4.3to-0.8%],p = 0.004) and patients with private insurance decreased, and those with Medicaid coverage increased (adjusted-DD 9.7% [95%-CI 6.9-12.5%],p < 0.001) in expansion states after ACA implementation. The percentage of patients with pT1 did not differ between expansion and non-expansion states; neither did the use of RAI.

Conclusions: Medicaid expansion has resulted in a smaller uninsured population in PTC patients, but without earlier disease presentation nor change in RAI treatment.

Keywords: Affordable care act; Expansion; Medicaid; Papillary thyroid cancer; Radioactive iodine.