The expansion of Medicaid coverage under the Affordable Care Act was associated with a 6% drop in total opioid overdose deaths nationally, a new study concludes.

Medicaid expansion may have saved as many as 8,132 people from overdosing on heroin and fentanyl by providing additional access to drug addiction treatment, The Washington Post reports.

The study compared changes in opioid overdose rates in counties located in states that expanded Medicaid and counties in states that did not expand Medicaid.

“Past research has found Medicaid expansion is associated with not only large decreases in the number of uninsured Americans, but also considerable increases in access to opioid use disorder treatment and the opioid overdose reversal medication naloxone,” study lead author Nicole Kravitz-Wirtz, PhD, MPH, said in a news release. “Ours was the first study to investigate the natural follow-up question: Is the expansion associated with reductions in local opioid overdose deaths? On balance, the answer appears to be yes.”