Changes in Breast and Colorectal Cancer Screening After Medicaid Expansion Under the Affordable Care Act.

INTRODUCTION: Medicaid expansions following the Affordable Care Act have improved insurance coverage in low-income adults, but little is known about its impact on cancer screening. This study examined associations between Medicaid expansion timing and colorectal cancer (CRC) and breast cancer (BC) screening.
METHODS: Up-to-date and past 2-year CRC (n=95,400) and BC (women, n=43,279) screening prevalence were computed among low-income respondents aged 50-64 years in 2012, 2014, and 2016 Behavioral Risk Factor Surveillance System data. Respondents were grouped according to Medicaid expansion timing as: very early ([VE] six states expanding March 1, 2010-April 14, 2011), early (21 states expanding January 1, 2014-August 15, 2014), late (five states expanding January 1, 2015-July 1, 2016), and non-expansion states (19 states). Absolute adjusted difference-in-differences (aDDs) were computed in 2018-2019 (ref, non-expansion states).
RESULTS: Between 2012 and 2016, absolute up-to-date CRC screening increased by 8.8%, 2.9%, 2.4%, and 3.8% among low-income adults in VE, early, late, and non-expansion states, respectively. Past 2-year CRC screening increased by 8.0% in VE and 2.8% in non-expansion states, with an aDD of 4.9% (p=0.041). In 2012-2016, up-to-date BC screening increased by 5.1%, 4.9%, and 3.7% among low-income women in VE, early, and non-expansion states, respectively, but aDDs were not statistically significant.
CONCLUSIONS: Prevalence of CRC and BC screening among low-income adults rose in Medicaid expansion states, though increases were significantly higher than those in non-expansion states only for recent CRC screening in VE expansion states. Large-scale improvements in cancer screening may take several years following expansion in access to care.