Understanding the Implications of Medicaid Expansion for Cancer Care in the US: A Review.

IMPORTANCE: Insurance status has been linked to important differences in cancer treatment and outcomes in the US. With more than 15 million individuals gaining health insurance through Medicaid expansion, there is an increasing need to understand the implications of this policy within the US cancer population. This review provides an overview of the fundamental principles and nuances of Medicaid expansion, as well as the implications for cancer care. OBSERVATIONS: The Patient Protection and Affordable Care Act presented states with an option to expand Medicaid coverage by broadening the eligibility criteria (eg, raising the eligible income level). During the past 10 years, Medicaid expansion has been credited with a 30% reduction in the population of uninsured individuals in the US. Such a significant change in the insurance profile could have important implications for the 1.7 million patients diagnosed with cancer each year, the oncology teams that care for them, and policy makers. However, several factors may complicate efforts to characterize the effect of Medicaid expansion on the US cancer population. Most notably, there is considerable variation among states in terms of whether Medicaid expansion took place, when expansion occurred, eligibility criteria for Medicaid, and coverage types that Medicaid provides. In addition, economic and health policy factors may be intertwined with factors associated with Medicaid expansion. Finally, variability in the manner in which cancer care has been captured and depicted in large databases could affect the interpretation of findings associated with expansion. CONCLUSIONS AND RELEVANCE: The expansion of Medicaid was a historic public policy initiative. To fully leverage this policy to improve oncological care and to maximize learning for subsequent policies, it is critical to understand the effect of Medicaid expansion. This review aims to better prepare investigators and their audiences to fully understand the implications of this important health policy initiative.