Han X, et al. - Given that, having health insurance is a strong determinant of cancer outcomes in the United States, and Medicaid expansion under the Patient Protection and Affordable Care Act (ACA) may have reduced the prevalence of uninsured patients, researchers investigated nonelderly patients with cancer, to determine how the percentage of uninsured patients and stage at diagnosis change by state and key sociodemographic factors after implementation of the ACA. They observed that, following the implementation of the ACA, the reductions in the percentage of uninsured patients varied across states, with larger decreases in expansion than nonexpansion states. Findings suggested a promising role of Medicaid expansion in reducing disparities among sociodemographic subpopulations because Medicaid expansion states showed diminished or eliminated disparities in the percentage of uninsured patients by race/ethnicity, census tract–level poverty, and rurality, however, these disparities remained high in nonexpansion states.

Methods

• Using difference-in-differences analysis and the population-based cancer registries of 40 states, researchers determined the percentage of uninsured patients and early-stage cancer diagnoses among patients aged 18 to 64 years before (January 1, 2010, to December 31, 2013) and after (January 1, 2014, to December 31, 2014) the ACA Medicaid expansion.
• From November 2017 to April 2018, they analyzed the data.
• Main outcomes and measures included changes in the percentage of uninsured patients and early-stage diagnoses.

Results

• From Medicaid expansion (n=1,234,156) and nonexpansion (n=1,236,998) states, 2 471 154 patients (mean age, 52.7 years; age range, 18-64 years; 51.4% female; 70.9% non-Hispanic white) were included.
• A decrease in the percentage of uninsured patients was reported in almost all states in 2014.
• However, expansion vs nonexpansion states had greater decreases; the greatest decreases were observed in expansion states with high baseline uninsured rates.
• For illustration, in the expansion state of Kentucky vs in the nonexpansion state of Tennessee, the respective percentage decrease of uninsured patients was 8.3% before implementation of the ACA to 2.1% (−6.2 difference) after implementation of the ACA vs 9.1% to 7.5% (−1.5 difference).
• They found that in expansion states, the decreases in the percentage of uninsured patients were higher among minorities and patients in high-poverty or rural areas, diminishing or eliminating disparities.
• In contrast, nonexpansion states had high sociodemographic disparities in the percentage of uninsured patients.
• In Medicaid expansion states, a slight shift of stage at diagnosis to earlier stage for most cancer types was observed.