Since 2016, a federal regulation has allowed nurse practitioners and physician assistants to obtain a waiver to prescribe buprenorphine, a medication used to treat opioid use disorder as a medication assisted treatment.
But a recent study by Indiana University researchers found the bill, called the Comprehensive Addiction and Recovery Act (CARA), has not greatly increased the amount of nurse practitioners prescribing buprenorphine, especially in states that have further restrictions. The study was published in Medical Care Research and Review.
"Nurse practitioners and physician assistants are an important workforce with a capacity to expand treatment access for those with substance use disorders," said Kosali Simon, co-author of the study and a Herman B. Wells Endowed Professor in IU's O'Neill School of Public and Environmental Affairs. "But we have found that efforts like CARA have been limited in actually utilizing this group, with nurse practitioners accounting for a relatively small proportion of buprenorphine prescriptions."
Buprenorphine is the only agonist medication for opioid addiction that can be prescribed by a qualified physician or nonphysician practitioner in an office-based setting. Simon said research has shown it is associated with significant decreases in relapse and overdose. However, the U.S. has a shortage of providers who have a waiver, known as an X waiver, from the Drug Enforcement Administration to prescribe buprenorphine outside of opioid treatment programs.
Through the Comprehensive Addiction and Recovery Act nurse practitioners and physician assistants to prescribe buprenorphine to up to 30 patients at a time for their first year, and after that, they can obtain authorization to prescribe to up to 100 patients. Some states mandate further restrictions though, including those that limit the authority of nurse practitioners to prescribe.
Kosali and a team of researchers from various universities used pharmacy claims data between January 2015 and September 2018 from Optum's deidentified Clinformatics DataMart to examine the impact of federal and state scope-of-practice regulations on nurse practitioner's buprenorphine prescribing.
At the county-level, researchers found the proportion of patients filling prescriptions written by nurse practitioners was low even after CARA: 2.7% in states that did not require physician oversight of nurse practitioners and 1.1% in states that did. While analyses in rural counties showed higher rates of buprenorphine prescriptions written by nurse practitioners, the study found rates were still considerably low - 3.7% in states with less restrictive regulations and 1.1% in other states.
Simon said since relatively few physicians have a waiver to prescribe, it can be difficult for nurse practitioners who must have physician oversight to find a waivered physician to oversee them. Some also face supervising physicians who are unsupportive of buprenorphine treatment.
"These results indicate that less restrictive scope-of-practice regulations are associated with greater nurse practitioner prescribing following CARA," Simon said. "The small magnitude of the changes indicates that federal attempts to expand treatment access through CARA have been limited. More is needed so people with substance use disorder have access to medication assistant treatment."
While state restrictions did not help, the researchers said there are more deterrents involved including insufficient training and education about opioid use disorder treatment, burdensome training time, lack of institutional and clinician peer support, poor care coordination and inadequate insurance reimbursement.
Researchers recommend relaxing state scope-of-practice requirements for nurse practitioners and addressing other practice-level and educational barriers that impede treatment access. Additionally, Simon said eliminating the need for an X waiver for all practitioners should be further considered to help address gaps in opioid use disorder care, especially in primary care settings and rural areas. Alternatively, current X waiver training requirements could be decreased for certain clinicians, including nurse practitioners and physician assistants, who have previously completed substance use disorder treatment training during residency.
Study co-authors include Thuy Nguyen, University of Michigan; Ulrike Muench, University of California San Francisco; Barbara Andraka-Christou, University of Central Florida and Joanne Spetz, University of Georgia.
Responding to the Addictions Crisis
The Responding to the Addictions Crisis Grand Challenge initiative engages a broad array of IU's world-class faculty, as well as IU's business, nonprofit and government partners. Working together, the groups are contributing to an initiative to implement a comprehensive plan to reduce deaths from addiction, ease the burden of drug addiction on Hoosier communities and improve health and economic outcomes. This initiative is one of the nation's largest and most comprehensive state-based responses to the opioid addiction crisis -- and the largest led by a university.