Medicaid Expansion and Stage-Specific Colorectal Cancer Survival.

Area of Science:

• Health Services Research
• Oncology
• Public Health Policy

Background:

• Medicaid expansion under the Affordable Care Act (ACA) is linked to better colorectal cancer (CRC) outcomes.
• Benefits are often attributed to earlier diagnosis, but survival impacts across disease stages are unclear.

Purpose of the Study:

• To assess cancer-specific survival (CSS) for colorectal cancer (CRC) patients by disease stage after Medicaid expansion.
• Compare outcomes in California (expansion state) versus Texas (non-expansion state) among working-age adults.

Main Methods:

• Retrospective cohort study using SEER registry data (2007-2021) for patients aged 18-64 with primary CRC.
• Difference-in-differences analysis comparing pre-ACA (2007-2013) and post-ACA (2015-2021) periods.
• Cox regression models stratified by disease stage and race/ethnicity.

Main Results:

• Overall CSS improved in California post-Medicaid expansion compared to Texas.
• Survival gains were stage-dependent: modest for localized, larger for regional, and greatest for distant metastatic CRC.
• Improvements observed across racial/ethnic groups, with significant gains for non-Hispanic Black patients.

Conclusions:

• Medicaid expansion is associated with stage-dependent improvements in CRC survival.
• The most significant survival benefits were seen in patients with metastatic disease.
• Enhanced access to care, including systemic therapy and financial protection, likely contributes to these survival gains beyond early detection alone.