Shedding light on the ongoing discussion of the ideal duration of medication treatment for opioid use disorder (OUD), a new study has reported more favorable post-treatment outcomes for patients who had received buprenorphine for longer periods.
Published online this month in the American Journal of Psychiatry, the cohort study involving nearly 9,000 patients found lower risk of hospitalization, filled opioid prescriptions and other adverse outcomes for patients who had been retained on buprenorphine for 15 to 18 months. The results should boost the argument that buprenorphine has a strong protective effect when used for long-term treatment.
“The take-home here is there do seem to be benefits to extended treatment,” study co-author Mark Olfson, MD, MPH, research psychiatrist at the New York State Psychiatric Institute and professor of psychiatry at Columbia University Medical Center, tells Addiction Professional.
Olfson acknowledges that these results might not exactly be welcomed in settings where providers still harbor skepticism about extended medication-assisted treatment for OUD and often appear to want to get their patients off the drug as quickly as possible, despite a growing body of empirical evidence supporting longer-term treatment.
Where the duration of treatment did not appear to make a difference in outcomes in this study concerned incidents of medically treated opioid and non-opioid overdose. Those rates were found to be relatively consistent across all durations of buprenorphine treatment.
This, combined with a relatively high overall incidence of post-treatment adverse events such as emergency department visits, points to the ongoing challenges involved in maintaining success for patients with OUD.
Details of study
“My sense is that when you get beyond 14 weeks or so of treatment, there are no clinical trials to give us guidance on how long someone should be on buprenorphine,” Olfson says. Given the challenges inherent in following patients with OUD for periods of up to a year or even longer, retrospective cohort studies remain an important analytical tool.
This cohort study examined 2013-2017 data from Medicaid claims, covering an important population in that Medicaid has become the largest single payer for addiction treatment services. The study sample comprised adults ages 18 to 64 at buprenorphine initiation who stayed on the medication for at least six months and remained on Medicaid for at least another six months after treatment discontinuation.
The researchers compared hospitalization rates, opioid prescription fills and drug overdoses in the six months following treatment discontinuation for individuals who had been retained in buprenorphine treatment for 6 to 9 months, 9 to 12 months, 12 to 15 months and 15 to 18 months. Among the 8,996 individuals studied, 61% of whom were women and three-quarters of whom were ages 25 to 44, the 15-to-18 month group had significantly lower rates of emergency department visits, all-cause inpatient hospitalization and opioid prescriptions.
The other groups with longer treatment duration than the 6-to-9 month group also showed more favorable outcomes than the group with the shortest duration of treatment, but the differences were not statistically significant.
Study authors wrote that “the results are consistent with a growing literature underscoring the protective effects of long-term pharmacotherapy for opioid use disorder as opposed to short-term use or brief detoxification.”
Overall rates of emergency department visits were in the 40 to 50% range across all groups. The overall overdose rate across the cohort in the six months following buprenorphine discontinuation was 5.2%, with no major between-group differences.
The study authors wrote, “Although the study design cannot establish a causal relationship between longer retention and clinical outcomes, the result suggest that post-discontinuation benefits may not begin to accrue until well after the 6-month mark,” a duration that has been set forth in some empirically based guidelines.
Olfson emphasizes that in real-world clinical practice, many patients who receive buprenorphine don't even stay on it past the initial weeks of treatment, for a variety of reasons around logistics, stigma and other barriers. It is important to identify more effective strategies to improve retention in MAT, he says.