Medicaid expansion increases cancer clinical trial participation

The Medicaid expansion under the Patient Protection and Affordable Care Act resulted in a 19% annual increase in Medicaid-insured cancer patients participating in publicly funded clinical trials, according to researchers from Fred Hutchinson Cancer Center, the SWOG Statistics and Data Management Center and Columbia University.

Published in JAMA Oncology, the study explored the impact of Medicaid expansion in 2014 and 2015 on cancer clinical trial participation. Researchers found that the 19% annual increase, compounded over time, resulted in 52% more patients with Medicaid insurance participating in cancer clinical trials than was projected during the same time period had the policy not been implemented.

An individual's type of insurance can be a strong indicator of their socioeconomic status, and so represents a social determinant of health. We embarked on this analysis to better understand the extent to which this policy increased access to lifesaving cancer clinical trials for people insured through Medicaid."

Joseph Unger, PhD, a health services researcher and associate professor in the Public Health Sciences Division at Fred Hutch

Using data from the SWOG Cancer Research Network of 51,751 people with cancer who participated in trials from 1992 to 2020, the researchers compared trends in Medicaid enrollment before the policy was enacted to trends in the years following its implementation. In the years before the policy was enacted, researchers observed that enrollment in Medicaid corresponded largely to fluctuations in national economic conditions, especially patterns of unemployment.

"This is an important finding in its own right, as it shows how socioeconomic conditions are strongly associated with who enrolls in clinical trials," Dr. Unger said. "This suggests that, going forward, it is important for researchers to more commonly consider the societal background of the participants when designing and conducting clinical trials and analyzing study data."

In the years following enactment of the Affordable Care Act, the researchers found that increases in Medicaid enrollment were no longer closely associated with national economic events. They also found that the impact of the policy change was more profound in states that implemented the Medicaid expansion in 2014 or 2015, compared to states that implemented it in later years or didn't implement it at all.

"This study demonstrates that targeted policies not only can increase overall access to health care among cancer patients, but also increase the accessibility of participating in a clinical trial," said Unger. "Combined with a recent law requiring that state Medicaid programs cover the routine costs of participating in cancer clinical trials and new federal guidelines to design clinical trials to increase participation among underserved groups, we hope to see continued benefits in access to cancer clinical trials for people insured by Medicaid."

The study is based on data from National Cancer Institute-funded clinical trials but does not include data from trials sponsored by pharmaceutical companies. In the future, the researchers suggest analyzing whether their findings extend to cancer clinical trials that are not publicly funded.

"It is reassuring as a researcher and a physician to see that efforts to increase insurance access can impact the accessibility of clinical trials and improve generalizability of the results," said Dawn Hershman, MD, MS, FASCO, Interim Chief, Division of Hematology Oncology at Columbia University Medical Center/NYP and Deputy Director, Herbert Irving Comprehensive Cancer Center. "These policy decisions make a difference, and we need to continue to advocate for them as a community."

This study was funded by the National Institutes of Health, National Cancer Institute, National Clinical Trials Network, the Hope Foundation for Cancer Research and the American Cancer Society. Study authors reported receiving support from the NIH, NCI and ACS during the conduct of this study.