Association of Medicaid Expansion Under the Affordable Care Act with Insurance Status and Clinical Characteristics of Low-Income Patients with Newly Diagnosed Melanoma

Importance The Affordable Care Act expanded Medicaid eligibility in participating states to individuals with incomes up to 138% of the federal poverty line. The effects of this policy on the diagnosis and treatment of melanoma in low-income populations has yet to be described. Objective To evaluate the effect of Medicaid expansion on changes in insurance status and clinical characteristics of low-income patients with newly diagnosed melanoma. Design, Setting, and Participants This cross-sectional study included patients younger than 65 with a new diagnosis of malignant melanoma from January 1, 2011 to December 31, 2016, in the US National Cancer Institute’s Surveillance Epidemiology and End Results database. Exposures Residence in a state that expanded Medicaid on January 1, 2014. Main Outcomes and Measures The primary outcomes were insurance status, melanoma staging, and overall survival. Results In Medicaid expansion states, there were 1,719 low-income patients with newly diagnosed melanoma during the pre-expansion time period and 1,984 (15% increase) during the post-expansion time period. In nonexpansion states, there were 326 low-income patients with newly diagnosed melanoma during the pre-expansion time period, and 288 during the post-expansion time period (12% decrease). Compared with nonexpansion states, expansion states had a significantly greater reduction in percentage of uninsured patients following Medicaid expansion (adjusted odds ratio, 6.27 [95% CI, 4.83 to 8.14]). Overall survival was not statistically different between expansion and nonexpansion states (HR, 0.89 [95% CI, 0.74 to 1.06]). There were no statistically significant differences in melanoma staging at diagnosis between the expansion and nonexpansion groups (p = 0.05). Conclusions and Relevance Medicaid expansion was associated with increased melanoma diagnoses in low-income patients and a decreased proportion of uninsured patients. However, our study did not identify differences in clinical outcomes associated with Medicaid expansion. Key Points Question Was Medicaid expansion associated with changes in insurance status and clinical characteristics of low-income melanoma patients? Findings Medicaid expansion was associated with increased diagnoses of melanoma in low-income populations and reductions in the proportion of uninsured melanoma patients. However, there were no statistically significant changes in staging at diagnosis or overall survival associated with Medicaid expansion. Meaning Increased health insurance coverage associated with Medicaid expansion could potentially improve timely detection and treatment of melanoma for low-income populations.