Associations of Medicaid expansion with stage at diagnosis, timely initiation and receipt of guideline-concordant treatment, and survival among individuals newly diagnosed with non-small cell lung cancer.

47 Background: Medicaid expansion under the Patient Protection and Affordable Care Act improved health insurance coverage among patients with cancer. Individuals with non-small cell lung cancer (NSCLC) may benefit from Medicaid expansion throughout the cancer control continuum. This study examined the associations of Medicaid expansion with stage at disease diagnosis, timely initiation and receipt of guideline-concordant treatment, and five-year overall survival among individuals with NSCLC. Methods: We identified individuals newly diagnosed at age 18-64 with stages I-IV first primary NSCLC between January 1, 2008 and December 31, 2019 in 50 states and Washington, D.C. from the National Cancer Database (n=332,368). We examined the associations of Medicaid expansion with (1) diagnosis stage, which was categorized into early (I (2) timely initiation of guideline-concordant treatment within 30 days after cancer diagnosis (yes/no); (3) receipt of guideline-concordant treatment (yes/no) derived from the National Comprehensive Cancer Network cancer treatment guidelines; and (4) five-year overall survival. We applied a difference-in-differences (DD) approach to examine the changes in study outcomes associated with Medicaid expansion, controlling for key sociodemographic and clinical factors. Results: The percentage of early-stage diagnoses increased from 23.1% pre-expansion to 31.9% post-expansion in expansion states and from 22.3% to 29.5% in non-expansion states, translating to greater increase of 1.7 (95% confidence interval (CI): 0.3-3.1) percentage points (ppt) in expansion states after adjustment (Table). Medicaid expansion was also associated with greater increases in timely initiation of guideline-concordant care (DD: 1.6 (95% CI: 0.1-3.1) ppt) and five-year overall survival (DD: 1.3 (95% CI: 0.7-1.9) ppt). Conclusions: Medicaid expansion may improve access to NSCLC care and outcomes across the cancer control continuum, from early-stage diagnosis, treatment initiation, and overall survival. Association of Medicaid expansion and study outcomes among NSCLC patients. Expansion States Non-expansion States Pre-ME Post-ME Difference Pre-ME Post-ME Difference DD Adjusted DD Early-stage diagnosis 23.1 31.9 8.7 (7.4 to 10.1) 22.3 29.5 7.2 (6.2 to 10.1) 1.5 (-0.1 to 3.2) 1.7 (0.3 to 3.1) Timely initiation of guideline-concordant care 31.3 27.5 -3.9 (-5.3 to -2.4) 33.4 27.8 -5.6 (-6.24 to -2.4) 1.7 (0.1 to 3.3) 1.6 (0.1 to 3.1) Receipt of guideline-concordant care 65.2 68.2 2.9 (1.8 to 4.0) 62.9 66.4 3.5 (2.7 to 4.0) -0.6 (-2.0 to 0.8) -0.2 (-1.7 to 1.3) Five-year survival 21.3 34.8 13.5 (13.1 to 13.9) 18.6 30.2 11.6 (11.1 to 12.2) 1.9 (1.2 to 2.5) 1.3 (0.7 to 1.9) Abbreviation: ME, Medicaid expansion.