Association of State-Level Medicaid Expansion With Treatment of Patients With Higher-Risk Prostate Cancer

IMPORTANCE: The Patient Protection and Affordable Care Act broadened insurance coverage, partially through voluntary state-based Medicaid expansion. OBJECTIVE: To determine whether patients with higher-risk prostate cancer residing in Medicaid expansion states were more likely to receive treatment after expansion compared with patients in states electing not to pursue Medicaid expansion. DESIGN, SETTING, AND PARTICIPANTS: This population-based cohort study included 15 332 patients diagnosed with higher-risk prostate cancer (ie, grade group >2; grade group 2 with prostate-specific antigen levels >10 ng/mL; or grade group 1 with prostate-specific antigen levels >20 ng/mL) from January 2010 to December 2016 aged 50 to 64 years who were candidates for definitive treatment. Patients residing in states that partially expanded Medicaid coverage before 2010 (ie, California and Connecticut) and those with diagnosis not confirmed by histology were excluded. Data were collected from the Surveillance, Epidemiology, and End Results Program. Data were analyzed between August and December 2019. EXPOSURE: State-level Medicaid expansion status. MAIN OUTCOMES AND MEASURES: Insurance status before and after expansion, treatment with prostatectomy or radiation therapy (including brachytherapy), treatment trends over time. RESULTS: Of 15 332 patients, 7811 (50.9%) lived in expansion states (mean [SD] age, 59.1 [3.8] years; 5532 [71.9%] non-Hispanic White), and 7521 (49.1%) lived in nonexpansion states (mean [SD] age, 59.0 [3.9] years; 3912 [52.1%] non-Hispanic White). Residence in an expansion state was associated with higher pre-expansion levels of Medicaid coverage (292 [8.1%] vs 161 [3.8%]; odds ratio [OR], 2.12; 95% CI, 1.78 to 2.53) and lower likelihood of being uninsured (136 [3.2%] vs 38 [1.1%]; OR, 0.28; 95% CI, 0.15 to 0.54). After expansion, there was no difference in trends in treatment receipt between expansion and nonexpansion states (change, −0.39%; 95% CI, −0.11% to 0.28%; P = .25). Patients with private or Medicare coverage were more likely to receive treatment vs those with Medicaid or no coverage across racial/ethnic groups (eg, Black patients with coverage: OR, 2.30; 95% CI, 1.68 to 3.10; Black patients with no coverage: OR, 1.48; 95% CI, 1.09 to 2.00; P < .001). Medicaid patients were not more likely to be treated compared with those without insurance (737 [78.8%] vs 435 [79.5%]; OR, 0.97; 95% CI, 0.76 to 1.25). CONCLUSIONS AND RELEVANCE: In this cohort study, state-level expansion of Medicaid was associated with increased Medicaid coverage for men with higher-risk prostate tumors but did not appear to affect treatment patterns at a population level. This may be related to the finding that Medicaid coverage was not associated with increased treatment rates compared with those without insurance.