In an effort to find ways to improve long-term outcomes for people with opioid use disorder, University of Massachusetts Amherst epidemiology researcher Elizabeth Evans set out to study the obstacles to treating this chronic condition with an effective medication, buprenorphine-naloxone.
"Very few people with opioid use disorder ever get treatment for it - 10 percent or less," says Evans, assistant professor in the School of Public Health and Health Sciences. "Of those who do, few remain in treatment long enough to really benefit from it."
In a newly published paper in the Journal of Substance Abuse Treatment, lead author Evans, along with researchers at UCLA and the Veterans Affairs Puget Sound Health Care System in Seattle, identify factors that inhibit the long-term use of buprenorphine, which was approved in 2002 by the FDA to treat opioid use disorder.
"Patients and families still have that expectation that short-term treatment is what they should get and want," Evans says. "But they need to have more realistic expectations and understand that long-term treatment is often necessary."
In one of the few studies looking at a two-year period of buprenorphine treatment, the researchers analyzed data from a long-term, follow-up study of participants in a multisite randomized clinical trial, called START (Starting Treatment with Agonist Replacement Therapy), which was funded by the National Institute on Drug Abuse. Evans directed the study while doing research at the UCLA Semel Institute for Neuroscience and Human Behavior.
Conducted from 2011 to 2014, the study included long-term, follow-up interviews with a cohort of 1,269 adults with opioid use disorder in five states who had participated in a clinical trial comparing the effects of buprenorphine and methadone on liver health. About 9.3-11.2 percent of study participants used buprenorphine treatment over the two-year follow-up period that Evans and colleagues studied. A key finding was that individuals who perceived buprenorphine to be unacceptable were least likely to use the medication during follow-up, regardless of the perceived access to the medication.
"This points to the need to address people's experiences and perceptions of the medication - why they never tried it and, if they did, why they stopped taking the medication," Evans says. "Increasing access is important, but we need to address why people find that medication to be unacceptable."
Some of the other findings:
51.9 percent of participants said they had a problem getting buprenorphine when needed because, most commonly, it either wasn't accessible or affordable.
Among those not willing to continue taking buprenorphine, 54.1 percent said they were not using any opioids, 44.3 percent preferred methadone and 38.3 percent said they did not like buprenorphine.
The most common reasons cited for disliking buprenorphine were: negative physical reaction (72.9 percent), side effects (47.1 percent), can't feel opioids when taking buprenorphine (41.4 percent), had to pick it up at the clinic every day (38.6 percent) and the medication was not strong enough (30.0 percent).
Evans says all these perceptions and concerns can and need to be addressed. In addition, public health efforts should focus on education so that people with the condition, as well as their families and the public, understand that opioid use disorder usually requires long-term, if not lifetime, treatment.
"That's a challenge we face in the field," says Evans, who is co-principal investigator for a $10 million grant included in the Justice Community Opioid Innovation Network (JCOIN) initiative, an ambitious effort to improve opioid addiction treatment in criminal justice settings. "We need to flip the narrative. We know this is a chronic health condition. The good news is that buprenorphine is effective, but only if patients take it. We need to help patients access and use medication that will help them avoid a return to opioid use."