Objectives: To determine whether the 2014 Medicaid expansions facilitated by the Affordable Care Act affected overall and early-stage cancer diagnosis for nonelderly adults.
Methods: We used Surveillance, Epidemiology, and End Results Cancer Registry data from 2010 through 2014 to estimate a difference-in-differences model of cancer diagnosis rates, both overall and by stage, comparing changes in county-level diagnosis rates in US states that expanded Medicaid in 2014 with those that did not expand Medicaid.
Results: Among the 611 counties in this study, Medicaid expansion was associated with an increase in overall cancer diagnoses of 13.8 per 100 000 population (95% confidence interval [CI] = 0.7, 26.9), or 3.4%. Medicaid expansion was also associated with an increase in early-stage diagnoses of 15.4 per 100 000 population (95% CI = 5.4, 25.3), or 6.4%. There was no detectable impact on late-stage diagnoses.
Conclusions: In their first year, the 2014 Medicaid expansions were associated with an increase in cancer diagnosis, particularly at the early stage, in the working-age population. Public Health Implications. Expanding public health insurance may be an avenue for improving cancer detection, which is associated with improved patient outcomes, including reduced mortality.