Abstract
BACKGROUND: The Affordable Care Act implemented optional Medicaid expansion starting in 2014, but the association between Medicaid expansion and gynecologic cancer survival is unknown. OBJECTIVE: To evaluate the impact of Medicaid expansion by comparing 2-year survival among gynecologic cancers before and after 2014 in states that did and did not expand Medicaid using a difference-in-difference analysis. STUDY DESIGN: We searched the National Cancer Database for women aged 40 to 64 years, diagnosed with a primary gynecologic malignancy (endometrial, ovarian, cervical, vulvar, and vaginal) between 2010 and 2016. We used a quasiexperimental difference-in-difference multivariable Cox regression analysis to compare 2-year survival between states that expanded Medicaid in January 2014 and states that did not expand Medicaid as of 2016. We performed univariable subgroup difference-in-difference Cox regression analyses on the basis of stage, income, race, ethnicity, and geographic location. Adjusted linear difference-in-difference regressions evaluated the proportion of uninsured patients on the basis of expansion status after 2014. We evaluated adjusted Kaplan-Meier curves to examine differences on the basis of study period and expansion status. RESULTS: Our sample included 169,731 women, including 78,669 (46.3%) in expansion states and 91,062 (53.7%) in nonexpansion states. There was improved 2-year survival on adjusted difference-in-difference Cox regressions for women with ovarian cancer in expansion than in nonexpansion states after 2014 (hazard ratio, 0.88; 95% confidence interval, 0.82-0.94; P<.001) with no differences in endometrial, cervical, vaginal, vulvar, or combined gynecologic cancer sites on the basis of expansion status. On univariable subgroup difference-in-difference Cox analyses, women with ovarian cancer with stage III-IV disease (P=.008), non-Hispanic ethnicity (P=.042), those in the South (P=.016), and women with vulvar cancer in the Northeast (P=.022), had improved 2-year survival in expansion than in nonexpansion states after 2014. In contrast, women with cervical cancer in the South (P=.018) had worse 2-year survival in expansion than in nonexpansion states after 2014. All cancer sites had lower proportions of uninsured patients in expansion than in nonexpansion states after 2014. CONCLUSION: There was a significant association between Medicaid expansion and improved 2-year survival for women with ovarian cancer in states that expanded Medicaid after 2014. Despite improved insurance coverage, racial, ethnic, and regional survival differences exist between expansion and nonexpansion states.