Evaluating the Effect of Medicaid Expansion on Black/White Breast Cancer Mortality Disparities: A Difference-in-Difference Analysis

Abstract

PURPOSE Medicaid expansion was designed to increase access to health care. Evidence is mixed, but theory and empirical data suggest that lower cost of care through greater access to insurance increases health care utilization and possibly improves the health of poor and sick populations. However, this major health policy has yet to be thoroughly investigated for its effect on health disparities. The current study is motivated by one of today’s most stark inequalities: the disparity in breast cancer mortality rates between Black and White women. METHODS This analysis used a difference-in-difference fixed effects regression model to evaluate the impact of Medicaid expansion on the disparity between Black and White breast cancer mortality rates. State-level breast cancer mortality data were obtained from the Centers for Disease Control and Prevention. Each state’s Medicaid expansion status was provided by a Kaiser Family Foundation white paper. Two tests were conducted, one compared all expanding states with all nonexpanding states, and the second compared all expanding states with nonexpanding states that voted to expand—but did not by 2014. The difference-in-difference regression models considered the year 2014 a washout period and compared 2012 and 2013 (pretreatment) with 2015 and 2016 (posttreatment). RESULTS Medicaid expansion did not lower the disparity in breast cancer mortality. In contrast to expectations, the Black/White mortality ratio increased in states expanding Medicaid for all Medicaid-eligible age groups, with significant effects in younger age groups ( P = .01 to .15). CONCLUSION These results suggest that states cannot solely rely on access to insurance to alleviate disparities in cancer or other chronic conditions. More exploration of the impacts of low-quality health systems is warranted.

A narrative review of sociodemographic risk and disparities in screening, diagnosis, treatment, and outcomes of the most common extrathoracic malignancies in the United States

“…This may reflect either the existence of programs to ameliorate race-based survival disparities (e.g., mandatory insurance coverage), or more likely a lack of statistical power. Following Medicaid expansion, data from the Center for Disease Control and Prevention (CDC) was queried for survival disparities associated with race (13).…”

Data Demonstrating a Lack of Black and White Parity in Breast Cancer Mortality Following Medicaid Expansion: Are the Data Granular Enough to Support This?

“…We believe that Semprini and Olopade's 1 study suffers a number of shortcomings. Their study represents a snapshot of a bird's eye view of the ACA Medicaid expansion landscape.…”

“…We read the study by Semprini and Olopade 1 with great interest. In their difference-in-difference analysis of the impact of Medicaid expansion on Black and White breast cancer mortality, the authors found Black women to have a higher mortality rate than White women.…”

“…10 Our report underscores the importance of states or healthcare systems in obtaining granular data that are specific to their health organizations. We, therefore, recommend that readers should view the study by Semprini and Olopade 1 with a full understanding of its limitations.…”

Reply to Q. Chu et al

“…We appreciate Dr Chu et al 1 for their interest in our study evaluating Medicaid Expansion for its effect on Black and White breast cancer mortality gap. 2 Conducted in 2018, our study used state-level, CDC population data on breast cancer mortality rates to create a ratio, which measured the disparity in mortality between non-Hispanic Black and non-Hispanic White women. 3 Using a quasiexperimental design, we estimated the effect of Medicaid Expansion on this disparity.…”