Date of Award

Summer 2023

Document Type

Open Access Dissertation

Department

Public Health

First Advisor

Jan Eberth

Abstract

Introduction: When examining cancer outcomes, timely detection and treatment are critical factors for favorable prognoses. Previous studies have shown that individuals with public health insurance, specifically Medicaid, have worse cancer outcomes than those with private insurance. While differences in socioeconomic status may account for this disparity, one potential area for further investigation is the effect of Medicaid enrollment timing on cancer outcomes. In some states, individuals may not be eligible for Medicaid until after their cancer diagnosis, potentially nullifying health insurance benefits. This analysis examines the impact of Medicaid enrollment timing on cancer outcomes by comparing patients not enrolled in Medicaid, those enrolled before their cancer diagnosis, and those enrolled after their cancer diagnosis for breast, colon/rectum, and lung cancers.

Methods: We used data from a national sample of the Surveillance Epidemiology and End Results program of the National Cancer Institute, linked to national Medicaid enrollment data. Medicaid enrollment timing and insurance status were determined from the data. A state-level random intercept was included in the regression models to account for state-to-state variation. Logistic regression was used to examine tumor stage at diagnosis, interval-censored Cox proportional hazard regression was used for time to treatment, and competing risk Cox models were used to examine cancer-specific survival.

Results: This analysis included 276,555 breast cancer patients, 104,784 colon cancer patients, and 101,058 lung cancer patients. In fully adjusted models, compared to those not insured by Medicaid, enrolling in Medicaid before and after diagnosis significantly increased the odds of a late-stage diagnosis, a lower likelihood of initiating treatment, and a higher risk of death. Similarly, when comparing only those insured by Medicaid, those enrolled after their diagnosis as compared to those prior to their diagnosis had significantly higher odds of a late-stage diagnosis, a lower likelihood of early treatment initiation, and a higher risk of death for all cancers examined. Discussion: This analysis confirms previous findings that Medicaid-insured individuals have worse cancer outcomes than those with private insurance. Additionally, the study highlights the importance of Medicaid enrollment timing, showing that earlier enrollment is associated with better outcomes. This finding has important implications for Medicaid policy, suggesting that expanding eligibility requirements to include earlier enrollment may improve cancer outcomes and reduce the national burden of cancer.

Available for download on Sunday, August 31, 2025

Included in

Epidemiology Commons

Share

COinS