The effectiveness of substance use interventions for homeless and vulnerably housed persons: A systematic review of systematic reviews on supervised consumption facilities, managed alcohol programs, and pharmacological agents for opioid use disorder.

Olivia Magwood,Victoire Kpade,Tim O’Shea,Peter Tugwell,Claire Kendall,Zack Marshall,Kevin Pottie,Wahab Daghmach,Helen Hsu,Michaela Beder,Ginetta Salvalaggio,Robin Lennox,Ellen Snyder,Gilbert Habonimana

doi:10.1371/journal.pone.0227298

Abstract

BackgroundSubstance use is disproportionately high among people who are homeless or vulnerably housed. We performed a systematic overview of reviews examining the effects of selected harm reduction and pharmacological interventions on the health and social well-being of people who use substances, with a focus on homeless populations.Methods and findingsWe searched MEDLINE, EMBASE, PsycINFO, Joanna Briggs Institute EBP, Cochrane Database of Systematic Reviews and DARE for systematic reviews from inception to August 2019. We conducted a grey literature search and hand searched reference lists. We selected reviews that synthesized evidence on supervised consumption facilities, managed alcohol programs and pharmacological interventions for opioid use disorders. We abstracted data specific to homeless or vulnerably housed populations. We assessed certainty of the evidence using the GRADE approach.Our search identified 483 citations and 30 systematic reviews met all inclusion criteria, capturing the results from 442 primary studies. This included three reviews on supervised consumption facilities, 24 on pharmacological interventions, and three on managed alcohol programs. Supervised consumption facilities decreased lethal overdoses and other high risk behaviours without any significant harm, and improved access to care. Pharmaceutical interventions reduced mortality, morbidity, and substance use, but the impact on retention in treatment, mental illness and access to care was variable. Managed alcohol programs reduced or stabilized alcohol consumption. Few studies on managed alcohol programs reported deaths.ConclusionsSubstance use is a common chronic condition impacting homeless populations. Supervised consumption facilities reduce overdose and improve access to care, while pharmacological interventions may play a role in reducing harms and addressing other morbidity. High quality evidence on managed alcohol programs is limited.

Highlights

Homeless and vulnerably housed populations experience disproportionately high rates of substance use [1,2,3]
Supervised consumption facilities reduce overdose and improve access to care, while pharmacological interventions may play a role in reducing harms and addressing other morbidity
Of the 30 included systematic reviews, 24 reviews which included 352 unique primary studies reported on pharmacological interventions for opioid use disorder [41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64]

Summary

Introduction

Homeless and vulnerably housed populations experience disproportionately high rates of substance use [1,2,3]. Despite the substantial unmet care needs of this population, people struggling with both substance use and homelessness experience overlapping barriers to accessing care, including stigma related to care itself [9], and abstinence-based treatment first housing services [10,11]. Together, these barriers increase perceived loss of control over one’s life, contribute to mistrust of the health system, and perpetuate lower access and adherence to care and treatment [12,13,14]. We performed a systematic overview of reviews examining the effects of selected harm reduction and pharmacological interventions on the health and social well-being of people who use substances, with a focus on homeless populations

Methods

Results

Conclusion