(Reuters Health) - More low-income people addicted to opioids are getting diagnosed and treated with effective medication as a result of the Affordable Care Act, a new study suggests

Under the ACA, also known as Obamacare, some U.S. states expanded coverage through Medicaid - the joint federal and state insurance program for the poor - starting in 2014. While previous studies have linked Medicaid expansion to gains in the number of people treated for substance use disorders, the current study offers fresh evidence that the law helped to improve access to buprenorphine, a drug for treating opioid addiction.

“When people get signed up for Medicaid, it increases the likelihood that they will seek all types of medical care including more visits to primary care doctors, and even when patients are not explicitly seeking care for opioid addiction, the greater contact with the health system creates more opportunities for screening and diagnosis,” said lead study author Brendan Saloner of the Johns Hopkins Bloomberg School of Public Health in Baltimore.

“Our study did not look at the outcome of overdose or deaths, but there is a clearly established benefit of getting treated with buprenorphine and lower overdose risk,” Saloner said by email.

For the study, researchers focused on West Virginia, one of the states hardest hit by the nation’s opioid crisis.

As of 2016, West Virginia had a fatal opioid overdose rate of 43.4 deaths for every 100,000 residents, more than triple the U.S. average of 13.3 fatalities for every 100,000 people, the researchers note in Health Affairs.

In the first three years of Medicaid expansion in West Virginia, an average of 5.5 percent of all enrollees had a diagnosis of opioid use disorder each year, the study found. Over this same period, monthly opioid use disorder diagnoses nearly tripled.

During the study, the proportion of people diagnosed with opioid use disorder who filled prescriptions for buprenorphine climbed from about one-third to three-fourths. Over this period, average treatment duration also rose from 161 to 185 days.

Most people filling buprenorphine prescriptions also received counseling and drug testing.

Naltrexone, another drug for addiction, didn’t see dramatic gains in use during the study, and people tended to take it for shorter periods of time than buprenorphine.

“Methadone and buprenorphine have the strongest evidence supporting their effectiveness in opioid use disorder, but there are reasons a patient may prefer naltrexone,” said Lucas Hill of the University of Texas at Austin College of Pharmacy.

“The optimal duration of opioid use disorder treatment with medications has not been identified, but available evidence indicates longer treatment is generally better,” Hill, who wasn’t involved in the study, said by email.

The study wasn’t designed to determine the effectiveness of any treatments people received. It’s also not clear how accessibility or affordability of addiction treatment might have changed for people with other types of insurance.

“Buprenorphine/naloxone is more attainable through doctors’ offices, but it’s costly unless you are insured,” said Dr. Stefan Kertesz of the University of Alabama at Birmingham School of Medicine.

“The issue comes down to who will pay for the doctor’s office visit, the prescription medicine and the additional services that are needed,” Kertesz, who wasn’t involved in the study, said by email.

Many patients may also need treatment for health problems that contribute to opioid misuse like chronic pain or mental illness, as well as for conditions that can be caused by needle sharing among IV drug users like hepatitis and AIDS, said Talia Puzantian of the Keck Graduate Institute in Claremont, California.

“Medicaid clearly has a role in facilitating access to treatment,” Puzantian, who wasn’t involved in the study, said by email. “Repealing ACA or imposing new barriers to obtaining or maintaining Medicaid - for example work or premium requirements - would result in a significant barrier to life-saving treatment for which utilization is already low.”

SOURCE: bit.ly/2WDiFmY Health Affairs, online April 1, 2019.