Does implementation of office based addiction treatment by a nurse care manager increase the duration of OUD treatment in primary care? A secondary analysis of the PROUD randomized control trial.

Background: Implementation of office-based addiction treatment (OBAT) by nurse care managers increases overall use of OUD medication, but it is unknown whether it increases treatment duration among treated patients.

Methods: The Primary Care Opioid Use Disorders Treatment (PROUD) trial was a pragmatic, cluster-randomized trial testing whether implementation of OBAT increased OUD treatment in 12 primary care clinics in 6 systems. One of 2 clinics per system was randomized to implement OBAT (intervention), the other, usual care (UC). We evaluated treatment duration for the 3 years after nurses began seeing patients at clinics randomized to intervention vs. UC. The primary sample included patients newly initiating OUD medication; the secondary sample included patients with ongoing OUD medication. The primary outcome was percentage of days with OUD medications after treatment initiation, modeled using linear generalized estimating equations (GEE). Modified Poisson GEE models assessed secondary outcomes (≥80 % of days covered, ≥6 months on treatment).

Results: In adjusted analyses, the mean difference between intervention and UC in percent days treated was 6.3 % (95 % CI -9.6 %, 22.1 %) in the primary sample and 2.3 % (95 % CI -36.4 %, 31.8 %) in the secondary sample. There was no significant difference in treatment duration between intervention and UC patients in either primary or secondary outcomes.

Conclusions: Implementation of OBAT in this trial did not measurably increase duration of medication treatment among those treated for OUD compared to UC, suggesting that benefits of OBAT, at least in this trial, largely reflect increases in treatment access.