Medicaid Expansion Associated With Lower Colorectal Cancer Mortality

Adults with colorectal cancer (CRC) in states that expanded Medicaid under the Affordable Care Act (ACA) had lower mortality than those in nonexpansion states, with the largest relative reductions in mortality among Hispanic patients and those with stage IV disease, according to a cohort study published in JAMA Network Open.¹

Long-Term CRC Survival After Medicaid Expansion Remains Unclear

Although CRC incidence has declined among older adults, largely because of screening, early-onset disease is rising, with outcomes continuing to vary by insurance status, income, and race and ethnicity. Medicaid expansion has been linked to broader coverage, increased cancer screening, and earlier diagnosis, but most prior research focused on these outcomes rather than long-term survival. It has also remained unclear whether survival gains stem from earlier detection, improved access to treatment, or both.

To address this gap, researchers analyzed National Cancer Database (NCDB) data on adults aged 40 to 64 years diagnosed with CRC between 2006 and 2021. Using a difference-in-differences design, they compared states that expanded Medicaid between 2010 and 2014 with those that did not, analyzing outcomes across pre-ACA (2006-2013) and post-ACA (2014-2021) periods.

Hispanic Patients, Stage IV Disease Had Largest Mortality Reductions

The cohort included 658,593 adults (mean age, 54.9 years), the majority of whom were male (n = 366,800; 55.7%). In the post-ACA period, 2.4% of patients in expansion states were uninsured vs 9.7% in nonexpansion states, and Medicaid covered 19.0% vs 9.5% of those in the respective states. Compared with nonexpansion states, expansion states included fewer patients from the lowest income quartile (12.2% vs 25.6%) and more from the highest income quartile (45.0% vs 24.1%) in the post-ACA period (P < .001).

Medicaid expansion was associated with lower overall mortality (HR, 0.94; 95% CI, 0.93-0.95), corresponding to a 6.3% (95% CI, 5.1%-7.5%) relative reduction. The association varied considerably by race and ethnicity, the researchers highlighted. Hispanic patients had the largest benefit (HR, 0.77; 95% CI, 0.75-0.80), indicating a 22.6% (95% CI, 19.6%-25.4%; P < .001) relative reduction in mortality hazard. However, the authors flagged possible residual confounding by care setting because Hispanic patients were more concentrated in expansion states and at academic centers. Despite this, the Hispanic association weakened only modestly and remained significant after progressive adjustment for facility mix, including a within-facility comparison.

By contrast, reductions were more modest among non-Hispanic Black (HR, 0.96 [95% CI, 0.93-0.99]; relative reduction, 4.1% [95% CI, 0.7%-7.4%]; P = .02) and White patients (HR, 0.96 [95% CI, 0.94-0.97]; relative reduction, 4.3% [95% CI, 2.8%-5.7%]; P < .001). No significant association was observed among patients categorized as other race and ethnicity (HR, 0.95; 95% CI, 0.89-1.01; P = .10).

In addition, the association with lower mortality was observed across all disease stages, with the strongest association in stage IV disease (HR, 0.88; 95% CI, 0.83-0.94), corresponding to an 11.6% relative reduction (95% CI, 6.3%-16.6%; P < .001). By comparison, relative reductions were 5.4% (95% CI, 3.1%-7.7%) for stage I, 3.2% (95% CI, 0.7%-5.7%) for stage II, and 5.2% (95% CI, 2.9%-7.5%) for stage III disease.

Expansion was also associated with a 2.13–percentage-point increase in early-stage diagnosis, a 1.54–percentage-point increase in surgery, and a 0.68–percentage-point increase in receipt of any treatment. By contrast, chemotherapy and immunotherapy use declined by 1.30 and 1.62 percentage points, respectively.

Stage-stratified analyses showed the chemotherapy decline was concentrated in early-stage disease, where systemic therapy is often not guideline-indicated. The small immunotherapy decline, however, occurred in late-stage disease during a period of rapidly evolving indications tied to microsatellite instability status, which the NCDB does not capture.

Study Highlights Mortality Reductions Amid Medicaid Changes

The results were consistent with findings from another NCDB analysis published earlier this year of more than 1.5 million women with breast cancer.² That study linked Medicaid expansion to a 4.8% lower mortality hazard, with Hispanic women seeing a 19% reduction and patients with stage IV disease a nearly 14% reduction.

The findings also arrive as Medicaid coverage for adults in expansion states faces new constraints. As detailed in a commentary recently published in The American Journal of Managed Care^®, the One Big Beautiful Bill Act introduces semiannual eligibility redeterminations for adults in expansion states and establishes work requirements no later than January 1, 2027. The Congressional Budget Office estimates these changes will increase the number of uninsured people by 10 million in 2034.³

Still, the authors acknowledged several limitations of the current study, including its observational design and potential for residual confounding. In addition, restricting the cohort to adults younger than 65 years limits generalizability, they noted, as CRC incidence is highest among older adults. As a result, the researchers highlighted areas for further research.

“These findings suggest that Medicaid expansion was associated with improved [CRC] survival, but benefits may not have been uniformly distributed, underscoring the need for targeted strategies to address persistent disparities,” they wrote.

References

1. Akinyemi O, Oyebanji O, Oluborode B, et al. Medicaid expansion and mortality among patients with colorectal cancer. JAMA Netw Open. 2026;9(9):e2634827. doi:10.1001/jamanetworkopen.2026.34827
2. Hohmann E. Medicaid expansion linked to lower breast cancer deaths, but disparities persist. AJMC^®. March 4, 2026. Accessed October 7, 2026. https://www.ajmc.com/view/medicaid-expansion-linked-to-lower-breast-cancer-deaths-but-disparities-persist
3. Krishnan A. The One Big Beautiful Bill Act and cancer care: what oncology leaders need to know and do now. Am J Manag Care. 2026;32(9):484-486. doi:10.37765/ajmc.2026.90003