Inpatient Buprenorphine Initiation And Linkage To Outpatient Continuation Did Not Significantly Decrease Illicit Opioid Injection

Buprenorphine initiation in hospitalized patients with opioid use disorder and subsequent linkage to outpatient buprenorphine treatment have the potential to reduce illicit opioid use. However, it is not known whether this approach can reduce injection behavior among people who inject drugs (PWID). This planned sub-group analysis of PWID in a randomized trial compared inpatient buprenorphine initiation and linkage to outpatient buprenorphine (N=51) with 5-day inpatient buprenorphine detoxification (N=62). Thirty-day timeline follow-back self-report of injection opioid use was measured at 1, 3, and 6 months and compared between groups.

• At 1 month, the linkage group was more likely than the detoxification group to initiate with a buprenorphine program (71% versus 10%), but there was no difference between groups in continued engagement with a buprenorphine program at 6 months.
• Across groups, the odds of injection opioid use were 4.6 times greater on days when buprenorphine was not used.
• In Poisson regression models, injection opioid use did not differ significantly between linkage and detoxification groups at any follow-up point (incidence rate ratios [IRR], 1 month: 0.73 [p=0.32]; 3 months: 1.20 [p=0.54]; 6 months: 0.73 [p=0.23]). Given significant missing data (at each time-point, follow-up was <70% in the linkage group and <60% in the detoxification group), analyses were repeated with complete imputed datasets, yielding IRRs of 0.59, 0.77, and 0.55 for the linkage group, but between-group differences remained insignificant.

Comments:

This subgroup analysis of a well-done randomized trial did not show a decrease in injection opioid use for inpatient buprenorphine initiation and outpatient linkage, compared with inpatient detoxification alone. The main and imputed analyses gave a hint of benefit in the linkage group, but the sample size may have been too small. Among such challenging populations (e.g., safety net hospital with over one-third of participants experiencing homelessness), more intensive programs may be needed to decrease frequency of injection opioid use.

Kevin L. Kraemer, MD, MSc

Reference:

Cushman PA, Liebschutz JM, Anderson BJ, et al. Buprenorphine initiation and linkage to outpatient buprenorphine do not reduce frequency of injection opiate use following hospitalization. J Subst Abuse Treat. 2016;68:68–73.