Post–Affordable Care Act Improvements in Cancer Stage Among Ohio Medicaid Beneficiaries Resulted From an Increase in Stable Coverage

Abstract

Background: The mechanisms underlying improvements in early-stage cancer at diagnosis following Medicaid expansion remain unknown. We hypothesized that Medicaid expansion allowed for low-income adults to enroll in Medicaid before cancer diagnosis, thus increasing the number of stably-enrolled relative to those who enroll in Medicaid only after diagnosis (emergently-enrolled). Methods: Using data from the 2011–2017 Ohio Cancer Incidence Surveillance System and Medicaid enrollment files, we identified individuals diagnosed with incident invasive breast (n=4850), cervical (n=1023), and colorectal (n=3363) cancer. We conducted causal mediation analysis to estimate the direct effect of pre- (vs. post-) expansion on being diagnosed with early-stage (-vs. regional-stage and distant-stage) disease, and indirect (mediation) effect through being in the stably- (vs. emergently-) enrolled group, controlling for individual-level and area-level characteristics. Results: The percentage of stably-enrolled patients increased from 63.3% to 73.9% post-expansion, while that of the emergently-enrolled decreased from 36.7% to 26.1%. The percentage of patients with early-stage diagnosis remained 1.3–2.9 times higher among the stably-than the emergently-enrolled group, both pre-expansion and post-expansion. Results from the causal mediation analysis showed that there was an indirect effect of Medicaid expansion through being in the stably- (vs. emergently-) enrolled group [risk ratios with 95% confidence interval: 1.018 (1.010–1.027) for breast cancer, 1.115 (1.064–1.167) for cervical cancer, and 1.090 (1.062–1.118) for colorectal cancer. Conclusion: We provide the first evidence that post-expansion improvements in cancer stage were caused by an increased reliance on Medicaid as a source of stable insurance coverage.

Treatment Patterns and Survival Outcomes in Patients With Breast Cancer on Medicaid, Pre- and Post-Expansion

“…The main independent variable was a composite of With regard to the timing of enrollment in Medicaid, consistent with our previous study, 17 we considered women as stably enrolled if they enrolled in Medicaid at least 3 months prior to the diagnosis and remained continuously enrolled for 4 months postdiagnosis, and as emergently enrolled if they enrolled in Medicaid in the 3 months before or after cancer diagnosis.…”

“…Conversely, linked cancer registry and Medicaid files offer the benefit of conducting a detailed examination of cancer outcomes across Medicaid eligibility categories, including among those who enroll in Medicaid through the Breast and Cervical Cancer Prevention and Treatment Program. [11][12][13][14][15][16][17] The linked cancer registry and Medicaid files also allowed us to examine the heterogeneous composition of Medicaid enrollees 17 and to study cancer outcomes in the context of individuals' timing of enrollment in Medicaid relative to cancer diagnosis. 14,15,[17][18][19][20][21] Indeed, patients with cancer who enrolled in Medicaid several months prior to their cancer diagnosis (or the "stably enrolled") experience better outcomes than those enrolling in Medicaid just as they are diagnosed with cancer (or the "emergently enrolled").…”

“…[11][12][13][14][15][16][17] The linked cancer registry and Medicaid files also allowed us to examine the heterogeneous composition of Medicaid enrollees 17 and to study cancer outcomes in the context of individuals' timing of enrollment in Medicaid relative to cancer diagnosis. 14,15,[17][18][19][20][21] Indeed, patients with cancer who enrolled in Medicaid several months prior to their cancer diagnosis (or the "stably enrolled") experience better outcomes than those enrolling in Medicaid just as they are diagnosed with cancer (or the "emergently enrolled"). 17 From a policy standpoint, there have been several competing forces at play in the period following Medicaid expansion, potentially shaping cancer care and outcomes.…”

“…14,15,[17][18][19][20][21] Indeed, patients with cancer who enrolled in Medicaid several months prior to their cancer diagnosis (or the "stably enrolled") experience better outcomes than those enrolling in Medicaid just as they are diagnosed with cancer (or the "emergently enrolled"). 17 From a policy standpoint, there have been several competing forces at play in the period following Medicaid expansion, potentially shaping cancer care and outcomes. On the one hand, Medicaid expansion likely improved receipt of standard treatment, shortened time to treatment initiation (TTI), and improved survival given the increased access to care and use of highvalue care by Medicaid enrollees post-expansion.…”