The number of Medicaid recipients receiving medication to treat opioid abuse increased sharply in the years after approval of a new drug, but the increase was smaller in poorer counties and areas with larger populations of black and Hispanic residents, according to a new RAND Corporation study.
While the study provides evidence that more people are receiving the medication treatment recommended for opioid use disorders, the findings suggest that work is needed to address disparities that developed as treatment expanded, according to researchers.
"These findings highlight the good news that medication therapy is being used more widely to combat the nation's opioid epidemic," said Dr. Bradley D. Stein, the study's lead author and a senior physician scientist at RAND, a nonprofit research organization. "But it also raises concerns that there are racial/ethnic and income disparities that may prevent many individuals struggling with opioid addiction from receiving effective treatment."
The findings were published online by the journal Substance Abuse.
Opioid use disorders affect an estimated 9 out of every 1,000 Americans and opioid overdose-related deaths have quadrupled over the past 15 years. Medication-assisted treatment using methadone or buprenorphine can effectively treat opioid addiction and such care is considered the best option for people with opioid use disorders.
While methadone only can be dispensed in special clinics and commonly requires daily visits, the approval of buprenorphine in 2002 provided an alternative drug regime that can be prescribed by any specially certified physician.
In order to determine how much medication-assisted therapy expanded, RAND researchers analyzed Medicaid claims from 14 states from 2002 to 2009 to measure use of methadone and buprenorphine at the county level. Medicaid disproportionately covers individuals at higher risk for opioid use disorders and is the source of payment for more than one-third of all opioid addiction treatment episodes.
RAND researchers found that the number of Medicaid recipients who received medication-assisted treatment for opioid use disorders jumped by 62 percent during the study period. While methadone accounted for most treatment episodes, use of buprenorphine surged after its approval to account for almost one-third of treatment episodes in 2009.
Historically, there have been few sociodemographic disparities in access to treatment for substance use disorders. RAND researchers found that after accounting for whether a county was urban or rural, use of medication therapy did not vary with a county's poverty rate or ethnic/racial makeup in 2002.
However, by 2009 people who lived in counties with more poverty and higher percentages of blacks and Hispanics were significantly less likely to receive medication-assisted treatment for opioid use disorders.
In addition, researchers found that people who lived in urban counties were significantly more likely to receive medication-assisted treatment than people who lived in rural counties, although the although the difference grew smaller during the study period.
"The expansion of medication-assisted therapy appears to have created new disparities in this area of health care," Stein said. "We need research using more-current information to better understand whether the disparity is linked to the availability of medication-assisted therapy, differences in Medicaid eligibility or some other factor, and whether it has persisted."
The states in the study are California, Connecticut, Florida, Georgia, Illinois, Louisiana, Massachusetts, Maryland, New York, Pennsylvania, Rhode Island, Texas, Vermont and Wisconsin. The states account for nearly half of all Medicaid recipients.
Support for the study was provided by the National Institute on Drug Abuse. Other authors of the study are Andrew W. Dick, Mark Sorbero, Dr. Adam J. Gordon, Rachel M. Burns, Douglas L. Leslie and Rosalie Liccardo Pacula.
RAND Health is the nation's largest independent health policy research program, with a broad research portfolio that focuses on health care costs, quality and public health preparedness, among other topics.