Mortality Gap Between White and Minority Breast Cancer Patients Narrowed as Medicaid Expanded

By Linda Carroll

April 19, 2022

NEW YORK (Reuters Health) - The expansion of Medicaid may have helped diminish disparities in mortality between white and minority breast cancer patients, a new study suggests.

The cross-sectional population-based study, which used information from a national cancer database, revealed that survival differences observed between minority and white patients in the pre-expansion period were no longer present after the expansion, researchers report published in JAMA Oncology.

"The findings in our study suggest that policies aimed at improving equity and increasing access to healthcare, such as the Patient Protection and Affordable Care Act's expansion of Medicaid eligibility, can help reduce disparities in cancer outcomes," said Dr. Mariana Chavez-MacGregor of The University of Texas MD Anderson Cancer Center in Houston.

"Not only do our results highlight the positive impact of Medicaid expansion on survival for all patients with de novo stage IV breast cancer among states that expanded coverage in January 2014, but they also demonstrate that survival differences between white patients and those of racial and ethnic backgrounds present before Medicaid expansion were no longer present after expansion, suggesting a decrease in disparities," she told Reuters Health by email.

For their study, Dr. Chavez-MacGregor and her team turned to information from the National Cancer Database, which collects patient-level data on about 70% of all new cancer cases from more than 1,500 facilities. The researchers focused on patients diagnosed as having de novo stage-IV breast cancer between 2010 and 2016 who were between the ages of 40 and 64 so that their results wouldn't be affected by Medicare coverage.

Dr. Chavez-MacGregor and her colleagues compared overall survival and two-year mortality among patients residing in the 19 states that underwent Medicaid expansion January 2014 (Kentucky, Nevada, Colorado, Oregon, New Mexico, West Virginia, Arkansas, Rhode Island, Arizona, Maryland, Massachusetts, North Dakota, Ohio, Indiana, Illinois, Vermont, Hawaii, New York and Delaware).

The analysis included more than 9,300 patients (mean age, 55), of whom 5,077 were diagnosed in the pre-expansion period and 4,245 after the expansion. Among the 2,545 women in the racial- and ethnic-minority group were 500 Hispanic women, 1,515 non-Hispanic Black women, and 530 non-Hispanic women of other races, including American Indian and Alaska Native women.

The median follow-up from diagnosis to death was 2.5 years. In the pre-expansion period there were significant differences in overall survival between white women and minorities, with the two-year Kaplan-Meier estimate for white patients at 64% compared with 56% among the minority patients (P<0.001).

In the post-expansion period there was no longer a statistically significant difference between the two groups (72% vs. 71%, P=0.95).

Dr. Chavez-MacGregor believes that one of the reasons her team found an improvement in minority mortality is that their research focused only on states that expanded Medicaid.

"This analysis was a unique opportunity to evaluate trends while limiting potential biases arising from differences between states that chose to expand eligibility and those that did not," she told Reuters Health. "Although several studies have performed a similar statistical analysis, the overall follow-up since Medicaid expansion remains short. In our study, two-year mortality is an appropriate and relevant outcome since we are only including patient with stage-IV breast cancer."

Dr. Charles Shapiro, director of translational breast-cancer research and director of cancer survivorship at the Tisch Cancer Institute at the Icahn School of Medicine at Mount Sinai, in New York City, said the study was well done.

"The results are surprising in a way, and not, in another," Dr. Shapiro said. "In the pre-expansion period, as you would expect, white patients survived longer than racial and ethnic minorities. What happened post expansion is a bit of a surprise. It shows that if you have access to care you have a better chance at survival and that is what it's all about."

"Although we can't say that there is a causal relationship, it's logical to conclude that the expanded access to care resulted in the disparity going away," Dr. Shapiro told Reuters Health by email. "The results are somewhat reassuring that the differences we see are not due to biology, but to access."

SOURCE: JAMA Oncology, online April 7, 2022.