Date of Award
8-2025
Document Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Applied Health Research and Evaluation
Committee Chair/Advisor
Dr. Lu Zhang
Committee Member
Dr. Rachel Mayo
Committee Member
Dr. Khoa Truong
Committee Member
Dr. Xuesong Han
Abstract
Persistent disparities in non-small cell lung cancer (NSCLC) outcomes reflect broader structural inequities shaped by race, place, and socioeconomic conditions. This dissertation examined trends in NSCLC outcomes over the past two decades and evaluated the impact of Medicaid Expansion (ME) under the Affordable Care Act on improving outcomes and reducing disparities, especially in marginalized communities.
Using nationally representative datasets, three interrelated studies were conducted. The first assessed trends in NSCLC incidence, early-stage diagnosis, and 3-year survival from 2002-2021, stratified by metropolitan status, deprivation (Social Deprivation Index), and segregation (Index of Concentration at the Extremes). While incidence declined and early-stage diagnosis and survival improved overall, disparities persisted, particularly in rural, deprived, and segregated areas.
The second study used difference-in-differences models to evaluate ME’s effects on insurance coverage, early diagnosis, and survival among NSCLC patients aged 18-64 from 2009 to 2019. ME was associated with significant gains in coverage (+2.21 ppt), early diagnosis (+1.76 ppt), and 3-year survival (+1.81 ppt), with notable improvements in segregated communities and among non-Hispanic Whites.
The third study analyzed county-level mortality data from 2008 to 2019 to assess ME’s impact on all-cause and cause-specific mortality. ME was linked to reduced all-cause mortality (-2.97 per 100,000) and significant declines in mortality from heart disease, chronic respiratory disease, and homicide, especially in highly segregated counties.
Overall, findings show that while NSCLC outcomes have improved nationally, disparities remain. Medicaid expansion contributed meaningfully to improving NSCLC outcomes and reducing mortality, particularly in segregated communities, highlighting its value in advancing health equity.
Recommended Citation
Okon, Marvin Idoteyin, "Evaluating the Impact of Medicaid Expansion on Non-Small Cell Lung Cancer Care and Health Disparities" (2025). All Dissertations. 4020.
https://open.clemson.edu/all_dissertations/4020
Author ORCID Identifier
0000-0001-7429-3713
Comments
This dissertation explores the intersection of health policy and cancer equity, focusing on non-small cell lung cancer (NSCLC)—the most prevalent type of lung cancer in the United States. Despite overall progress in cancer care, persistent disparities in incidence, early detection, and survival continue to affect socially and geographically marginalized populations. This work investigates national trends in NSCLC outcomes over the past two decades and assesses the role of Medicaid Expansion under the Affordable Care Act as a structural intervention aimed at reducing these disparities.
Using multiple nationally representative datasets, this research is structured into three studies: (1) an analysis of trends in NSCLC incidence, early-stage diagnosis, and survival stratified by geography, neighborhood deprivation, and residential segregation; (2) an evaluation of Medicaid Expansion’s impact on insurance coverage, diagnosis, and survival outcomes among NSCLC patients; and (3) an assessment of the policy’s broader effects on all-cause and cause-specific mortality across U.S. counties. Findings demonstrate that while NSCLC outcomes have improved nationally, these gains have not been equitably shared. Medicaid Expansion was associated with significant improvements in cancer care outcomes and reductions in mortality, particularly in racially and economically segregated communities.
This dissertation contributes to the growing body of evidence on the health equity implications of Medicaid policy and underscores the need for sustained, place-based interventions to ensure that progress in cancer control reaches all populations.