Evaluation of heroin-assisted treatment in Norway: Protocol for a mixed methods study

Background

Opioid agonist treatmetn (OAT) for patients with opioid use disorder (OUD) has a convincing evidenve base, although variable retention rates suggest that it may not be benefivial for all. One of the options to include more patients is the introduction of heroin-assisted treatment (HAT) which involves the prescribing of pharmaceutical heroin in a clinical supervised setting. Clinical trials suggest that HAT positively affeects illicit drug use, criminal behaviour, quality of life, and health. Results are less clear for longer-term outcomes such as mortality, level of function and sosial integration. Most of the research on HAT orginates from randomized clinical trials that may have limitations concerning long-term outcomes and understanding of the mechanisms behind. This protocol describes a longitudinal evaluation of the introduction of HAT into the OAT services in two Norwegian cities over a 5-year period by the Norwegian Directorate of Health.

The main aim of the project is to study the individual, organizational and societal effecvts of implementing HAT in the specialized healthcare services for OUD.

Methods

The project adopts a multidisciplineray approach, where the primary cohort for analysis will consits of approximately 250 HAB-patients in Norway, included and observed during 2022-2026. Cohorts for comparative analysis will be all HAT-patients in Denmark from 2010-2022 (N=500), and all Norwegian patients in concentional OAT (N=8300). Data comes from indvidual interviews, self-report questionnaires, clincial records, and national registries, collected at several time-points throughout the treatment courses.

Qualitative analyses will use a flexible thematic approach. Quantitative analyses will employ a wide array of mehods including bi-variate parametric and non-parametric tests, and various forms of multivariate modeling.

Results

No conclusive results are available at presents du to ongoing and continual recruitment of subjects. Preliminary results may be presented.

Discussion

The project`s primary strenhgt lies in its comprehensive and longitudinal approach. It has the potential to reveal new insights on whether pharmaceuitical heroin should be an integral part of conventional OAT-services, to individually tailor treatments for patients with OUD. This could also affect conciderations beyond HAT-sepcific topics. An expanded undertanding of why some do not succeed with conventional OAT may strenghten the knowledge base for for drug treatment in general.  Results will be disseminated to the scientific community, clinicians, and policy makers.

The study was approved by the Norwegian Regional Committedd for Medical and Health Research Ethics (REK), ref.nr.195733.