Medicaid expansion improves early-stage cancer detection, research shows

The Affordable Care Act led to an increase in the number of cancer diagnoses -- particularly those at early stages -- in states where Medicaid was expanded, according to research from Indiana University.

The research, published in the American Journal of Public Health, suggests that public health insurance may increase cancer detection, which can lead to fewer cancer deaths and better outcomes for patients.

"Early detection is a key step to reducing cancer mortality, and our findings suggest that Medicaid expansion under the ACA led to more and earlier cancer detection," said the study's corresponding author, Aparna Soni, a doctoral candidate in business economics and public policy in the IU Kelley School of Business.

Previous research by Soni and her IU co-author, Kosali Simon, the Class of 1948 Herman B Wells Endowed Professor in the IU School of Public and Environmental Affairs, found that the Affordable Care Act increased insurance coverage among people already diagnosed with cancer.

Other co-authors of "Effect of Medicaid Expansions of 2014 on Overall and Early-Stage Cancer Diagnoses" were Lindsay Sabik, associate professor in health policy and management at the University of Pittsburgh; and John Cawley, professor of policy analysis and management and of economics at Cornell University.

In their study, researchers looked at cancer registry data from 2010 through 2014 to estimate post-ACA changes in county-level cancer diagnosis rates, both overall and by stages, in states that expanded Medicaid in 2014 versus those that did not. Medicaid expansion led to an increase of 15.4 early-stage diagnoses per 100,000 people, or 6.4 percent, from pre-ACA levels.

There was no detectable impact on late-stage diagnoses. The overall cancer diagnosis rate increased by 3.4 percent in Medicaid expansion states, compared with non-expansion states.

"These data indicate increases in health coverage lead to increased early detection, which raises the overall diagnosis rate," Simon said. "Medical research already shows that early cancer diagnosis is important for increasing the probability of successful treatment, reducing mortality and controlling costs. However, Medicaid expansion appears to have no effect on the diagnosis of late-stage cancers."

Using information about patients' age, tumor location and whether the cancer could be screened for, the researchers found that the increase in early-stage diagnoses was largely seen among those age 35 to 54 and with cancers that are easiest to detect.

"The fact that the increase in early-stage diagnoses was concentrated in cancers amenable to screening is consistent with the increase resulting from the expansion of health insurance and access to care," the researchers wrote in the paper.

The increase in overall diagnoses was largely driven by increases among those age 45 to 54 and among those with prostate cancer.