(HealthDay)—Expansion of Medicaid was associated with a reduction in the number of uninsured patients with breast cancer, according to a study published online July 1 in JAMA Surgery.

Justin M. Le Blanc, M.D., from the Yale University School of Medicine in New Haven, Connecticut, and colleagues characterized the link between stage and /ethnicity, age, and insurance status using data obtained from 2007 to 2016.

A total of 1,796,902 women were included in the study. The researchers found that 4.0 percent were uninsured or had Medicaid between 2012 and 2016. Among all races/ethnicities, reductions were seen in uninsured patients in expansion states (from 22.6 to 13.5 percent), and nonexpansion states (from 36.5 to 35.6 percent). There were reductions noted in advanced-stage disease from 21.8 to 19.3 percent in expansion states compared with 24.2 to 23.5 percent in nonexpansion states across all races. The incidence of advanced disease decreased from 24.6 to 21.6 percent among African-American patients in expansion states, while in nonexpansion states, it remained at approximately 27 percent (27.4 to 27.5 percent). The improvement was associated with a reduction in stage 3 diagnosis.

"Expansion of Medicaid was associated with a reduction in the number of with breast cancer and with decreased late-stage breast cancer presentation," the authors write.