A new study finds many opioid addiction programs, especially those in the Southeast, don’t accept Medicaid.

The study of 1,150 opioid addiction treatment programs found fewer than 750 accept Medicaid. States in the Southeast and Great Plains states were the least likely to accept Medicaid, HealthDay reports.

“I think the take-home message is really that, in the middle of an opioid epidemic, across the country, that many people, low income Americans, in particular, those on Medicaid, don’t have access to treatment for opioid use disorder,” lead author Amanda Abraham of the University of Georgia said in a news release. “And that’s a major problem because the Medicaid population has been disproportionately impacted by the opioid epidemic. They’re more likely to be prescribed opioids. And they’re also at higher risk for death from opioid overdose.”

The study was published in Health Services Research.