State Public Assistance Spending and Survival Among Adults With Cancer.

Importance: Social determinants of health contribute to disparities in cancer outcomes. State public assistance spending, including Medicaid and cash assistance programs for socioeconomically disadvantaged individuals, may improve access to care; address barriers, such as food and housing insecurity; and lead to improved cancer outcomes for marginalized populations. Objective: To determine whether state-level public assistance spending is associated with overall survival (OS) among individuals with cancer, overall and by race and ethnicity. Design, Setting, and Participants: This cohort study included US adults aged at least 18 years with a new cancer diagnosis from 2007 to 2013, with follow-up through 2019. Data were obtained from the Surveillance, Epidemiology, and End Results program. Data were analyzed from November 18, 2021, to July 6, 2023. Exposure: Differential state-level public assistance spending. Main Outcome and Measure: The main outcome was 6-year OS. Analyses were adjusted for age, race, ethnicity, sex, metropolitan residence, county-level income, state fixed effects, state-level percentages of residents living in poverty and aged 65 years or older, cancer type, and cancer stage. Results: A total 2 035 977 individuals with cancer were identified and included in analysis, with 1 005 702 individuals (49.4%) aged 65 years or older and 1 026 309 (50.4%) male. By tertile of public assistance spending, 6-year OS was 55.9% for the lowest tertile, 55.9% for the middle tertile, and 56.6% for the highest tertile. In adjusted analyses, public assistance spending at the state-level was significantly associated with higher 6-year OS (0.09% [95% CI, 0.04%-0.13%] per $100 per capita; P < .001), particularly for non-Hispanic Black individuals (0.29% [95% CI, 0.07%-0.52%] per $100 per capita; P = .01) and non-Hispanic White individuals (0.12% [95% CI, 0.08%-0.16%] per $100 per capita; P < .001). In sensitivity analyses examining the roles of Medicaid spending and Medicaid expansion including additional years of data, non-Medicaid spending was associated with higher 3-year OS among non-Hispanic Black individuals (0.49% [95% CI, 0.26%-0.72%] per $100 per capita when accounting for Medicaid spending; 0.17% [95% CI, 0.02%-0.31%] per $100 per capita Medicaid expansion effects). Conclusions and Relevance: This cohort study found that state public assistance expenditures, including cash assistance programs and Medicaid, were associated with improved survival for individuals with cancer. State investment in public assistance programs may represent an important avenue to improve cancer outcomes through addressing social determinants of health and should be a topic of further investigation.