Elsevier

The Lancet

Volume 391, Issue 10117, 20–26 January 2018, Pages 266-280
The Lancet

Review
What works in inclusion health: overview of effective interventions for marginalised and excluded populations

https://doi.org/10.1016/S0140-6736(17)31959-1Get rights and content

Summary

Inclusion health is a service, research, and policy agenda that aims to prevent and redress health and social inequities among the most vulnerable and excluded populations. We did an evidence synthesis of health and social interventions for inclusion health target populations, including people with experiences of homelessness, drug use, imprisonment, and sex work. These populations often have multiple overlapping risk factors and extreme levels of morbidity and mortality. We identified numerous interventions to improve physical and mental health, and substance use; however, evidence is scarce for structural interventions, including housing, employment, and legal support that can prevent exclusion and promote recovery. Dedicated resources and better collaboration with the affected populations are needed to realise the benefits of existing interventions. Research must inform the benefits of early intervention and implementation of policies to address the upstream causes of exclusion, such as adverse childhood experiences and poverty.

Introduction

Inclusion health is an emergent approach that aims to address extreme health and social inequities. Target populations have common adverse life experiences and risk factors such as poverty and childhood trauma that lead to social exclusion.1 Consequently, these populations have extremely poor health, multiple morbidity, and early mortality.2 Compounding these problems are numerous barriers to accessing health services.3 The key aims of the inclusion health agenda are to highlight the magnitude and consequences of extreme inequity, the need for preventive and early intervention approaches, and improved access to essential services for individuals harmed by exclusion.

An agreed conceptual framework for inclusion health has not yet been developed.2 In this Review, we employ existing social exclusion,4 intersectionality,5, 6 and life-course epidemiology7 perspectives, which examine how factors accumulate and intersect over time and affect health. Risk factors such as substance use, rough sleeping, imprisonment, and exchanging sex for money or drugs are known to overlap among populations that are socially excluded1 and lead to extremely poor health outcomes.2 This underscores the need to better understand what interventions can effectively address and prevent the multiple and complex needs of socially excluded populations as a whole, rather than focusing on subpopulations defined by singular risk factors. Our Review aims to provide an overview of which individual and structural interventions are effective to tackle the extreme health needs of inclusion health target populations.

We defined the Review operationally using the populations, interventions, comparators, outcomes8 method. Populations with histories of substance use disorders (excluding alcohol, cannabis, and tobacco), imprisonment, sex work, and homelessness in high-income countries were identified as target populations on the basis of previous research in the UK, which showed a high degree of overlap between these groups1, 6 and the need to coordinate services for them.9 Other important excluded groups, such as migrants and transgender populations, were beyond the scope of this Review. Full search terms are shown in the appendix. Additionally, we report a public engagement workshop that included people with experience of social exclusion, which aided the interpretation of the review findings (panel 1).

Key messages

  • People who are excluded from mainstream society, such as those experiencing homelessness, imprisonment, drug addiction, and sex work, have considerably higher rates of disease, injury, and premature mortality than the general population. Services need to tackle the so-called tri-morbidity of physical and mental illness, and addiction. Multiple evidence-based individual and structural interventions are available to prevent and address the excess burden of disease in these populations, but the need to translate and scale effective practice into action is crucial. Removal of barriers to access and uptake of services can be accelerated by involving people who have experience of social exclusion.

  • Extreme exclusion is associated with frequent use of acute services, providing a strong economic case for preventive action, which complements the compelling social justice case. Research on routes into homelessness has revealed a high prevalence of childhood trauma, including exposure to abuse, neglect, domestic violence, and parental mental ill-health and substance use disorders. These adverse life experiences have a strong social gradient, such that the highest risks are found in low-income populations. The most effective upstream prevention policy is likely to be reduction of material poverty and deprivation, especially among families with children who are at high risk of maltreatment.

  • Gaps in knowledge remain, particularly around interventions to improve upstream determinants of social inclusion, such as employment and education, which are also instrumental to long-term recovery from social exclusion. People who have experienced exclusion have identified appropriate housing as the most important intervention, and systematic reviews have established the effectiveness of this intervention for improving health and social outcomes.

Section snippets

Effective inclusion health interventions

We identified 272 potentially relevant systematic reviews of interventions with an effect on health or the social determinants of health for people with experience of homelessness, substance use disorders, imprisonment, or sex work in high-income countries (figure 1). We included 77 systematic reviews in the final review, including 17 Cochrane reviews, 49 reviews that included one or more randomised controlled trials, and 11 reviews of exclusively observational research (table 1).

Men aged 30–49

Pharmacological interventions

We identified pharmacological interventions for substance use disorders, dual diagnosis (mental illness and substance use disorders), and infectious diseases. Inclusion health target populations have an increased risk of tuberculosis, hepatitis C, and HIV infection,2 for which effective pharmacotherapies are available. However, these individuals experience numerous barriers to treatment engagement and adherence. A systematic review18 of HIV treatment adherence measures for people with substance

Psychosocial interventions

Literature on psychosocial interventions has primarily considered substance use disorders and mental health in the community and within the criminal justice system. The literature tends to support a multimodal approach,36 but insufficient evidence exists to identify the most effective intervention. A 2013 Cochrane review33 of 32 randomised controlled trials assessed psychosocial interventions to treat substance use disorders in people with severe mental illness. The authors reviewed long-term

Case management

Case management aims to improve the coordination and delivery of health and social care services and can be most simply understood by its functions: assessment, planning, linking health and social services, monitoring, and advocacy.46 Evidence for the effectiveness of case management is broad, and interventions are heterogeneous. For substance use disorders, case management has been shown to improve links with services46 and treatment processes,49 but little evidence exists overall for a

Disease prevention

Research on prevention of poor health outcomes largely consists of harm reduction interventions for people with substance use disorders, such as needle and syringe programmes, and screening and vaccination for blood-borne viruses, which are more prevalent in inclusion health target populations than the general population.2 The risk of HIV infection might be reduced by as much as a third among people with substance use disorders participating in needle and syringe programmes.54 Multicomponent

Housing and social determinants

Housing First is a well established intervention developed for people who are homeless with mental health and substance use problems.58 By contrast to treatment first models (ie, usual care), Housing First provides individuals with housing and subsequently attempts to engage them in mental health services, substance dependency treatment, and other services. A systematic review58 of randomised controlled trials of this intervention in the USA, Canada, and Europe significantly improved stable

Other interventions

Respite care (ie, short-term recuperative care for homeless individuals after hospital discharge) can reduce the number of future hospital admissions and use of emergency departments in homeless populations.62 Interventions delivered via computers, mobile phone apps, and the internet provide promising alternative health-care delivery models, and a systematic review63 of computer-based interventions for substance use disorders found that some measures of substance use were improved along with

Interventions tailored to women

Systematic reviews on tailored interventions for women focused on psychosocial therapies, case management or integrated programmes, and advocacy and empowerment. Interventions were rarely delivered in isolation, and pharmacological treatments, particularly for substance use disorders, were also described.

Educational interventions, cognitive behavioural therapy, and motivational interviewing improved psychological, behavioural, and cognitive outcomes among women who are homeless.71 For women in

Interventions tailored to young people

Little evidence exists for the effectiveness of tailored interventions that address the broad needs of socially excluded young people (eg, trust, subsistence, living skills, family or peer support, and safety).84 A 2016 Cochrane review80 examined a range of interventions compared with standard care for street-connected children and young people (children who work or sleep, or both, on the streets and might not necessarily be adequately supervised or directed by responsible adults). The

Putting the findings in context: views of experts by experience

People with experience of social exclusion, such as homelessness, addiction, or incarceration—known as experts by experience—collaborated on this paper through an engagement workshop with the research team to contextualise the review findings (panel 1). We explored inclusion health as a concept and discussed characteristics of target populations, barriers that lead to exclusion, and values and actions that promote inclusion (figure 2). Health statistics on target populations (as described by

Service planning implications

This Review identified several interventions that have been reported to be effective for socially excluded populations (panel 3). Most of the research has been done in the USA. Interventions with the strongest evidence base aimed to address substance use disorders and harm reduction and, to a lesser extent, mental health and infectious diseases. Several overlapping themes of effective interventions emerged, including individual care coordination of multicomponent interventions, active

Policy implications

Coordinated policies at the national and local level are required to address the material and the health needs of inclusion health target populations,1 consistent with a so-called whole-of-society approach to addressing health inequities and the reversal of exclusionary processes.93 Research on routes into homelessness has revealed that childhood trauma is common, including exposure to abuse, neglect, domestic violence, and parental mental ill-health and substance use disorders.1 A life-course

Conclusion

This Review identified a wide range of interventions for inclusion health target populations. The focus on systematic reviews enabled identification of interventions for which a body of evidence existed, but this approach will have excluded effective interventions that have not yet been the subject of such reviews. Strong evidence exists for the effectiveness of some interventions, particularly in the area of drug treatment and harm reduction, whereas the evidence in other areas is generally of

Search strategy and selection criteria

We reviewed the systematic review literature to provide an overview of effective interventions that directly affect health (eg, pharmacology, counselling, screening, prevention) or the wider determinants of health (eg, housing, social support, training and education, employment, crime, and recidivism). This enabled summation of a broad literature base that would not have been feasible if we had reviewed primary studies. We searched MEDLINE, Embase, PsychINFO, CINAHL, the Cochrane Collaboration

References (110)

  • T Elwell-Sutton et al.

    Factors associated with access to care and healthcare utilization in the homeless population of England

    J Public Health

    (2017)
  • R Peace

    Social exclusion: A concept in need of definition?

    Soc Policy J New Zeal

    (2001)
  • S Fitzpatrick et al.

    Hard edges: mapping severe and multiple disadvantage in England

  • S Fitzpatrick et al.

    Multiple exclusion homelessness in the UK: key patterns and intersections

    Soc Policy Soc

    (2011)
  • D Kuh et al.

    Life course epidemiology

    J Epidemiol Community Health

    (2003)
  • C Schardt et al.

    Utilization of the PICO framework to improve searching PubMed for clinical questions

    BMC Med Inform Decis Mak

    (2007)
  • M Cornes et al.

    Working together to address multiple exclusion homelessness

    Soc Policy Soc

    (2011)
  • RP Mattick et al.

    Methadone maintenance therapy versus no opioid replacement therapy for opioid dependence

    Cochrane Database Syst Rev

    (2009)
  • RP Mattick et al.

    Buprenorphine maintenance versus placebo or methadone maintenance for opioid dependence

    Cochrane Database Syst Rev

    (2014)
  • P Lobmaier et al.

    Sustained-release naltrexone for opioid dependence

    Cochrane Database Syst Rev

    (2008)
  • L Amato et al.

    Methadone at tapered doses for the management of opioid withdrawal

    Cochrane Database Syst Rev

    (2013)
  • AE Perry et al.

    Pharmacological interventions for drug-using offenders

    Cochrane Database Syst Rev

    (2013)
  • PP Pani et al.

    Disulfiram for the treatment of cocaine dependence

    Cochrane Database Syst Rev

    (2010)
  • S Minozzi et al.

    Anticonvulsants for cocaine dependence

    Cochrane Database Syst Rev

    (2015)
  • EE Lutge et al.

    Incentives and enablers to improve adherence in tuberculosis

    Cochrane Database Syst Rev

    (2015)
  • MC Binford et al.

    A systematic review of antiretroviral adherence interventions for HIV-infected people who use drugs

    Curr HIV/AIDS Rep

    (2012)
  • J Karumbi et al.

    Directly observed therapy for treating tuberculosis

    Cochrane Database Syst Rev

    (2015)
  • RB Dimova et al.

    Determinants of hepatitis C virus treatment completion and efficacy in drug users assessed by meta-analysis

    Clin Infect Dis

    (2013)
  • YP Bao et al.

    A meta-analysis of retention in methadone maintenance by dose and dosing strategy

    Am J Drug Alcohol Abus

    (2009)
  • Y Adi et al.

    Oral naltrexone as a treatment for relapse prevention in formerly opioid-dependent drug users: a systematic review and economic evaluation

    Health Technol Assess

    (2007)
  • MJ Horspool et al.

    Post-treatment outcomes of buprenorphine detoxification in community settings: a systematic review

    Eur Addict Res

    (2008)
  • D Hedrich et al.

    The effectiveness of opioid maintenance treatment in prison settings: a systematic review

    Addiction

    (2012)
  • J Strang et al.

    Heroin on trial: systematic review and meta-analysis of randomised trials of diamorphine-prescribing as treatment for refractory heroin addiction

    Br J Psychiatry

    (2015)
  • X Castells et al.

    Efficacy of central nervous system stimulant treatment for cocaine dependence: a systematic review and meta-analysis of randomized controlled clinical trials

    Addiction

    (2007)
  • Kishi T, Matsuda Y, Iwata N, Correll CU. Antipsychotics for cocaine or psychostimulant dependence: systematic review...
  • MM Koola et al.

    The potential role of long-acting injectable antipsychotics in people with schizophrenia and comorbid substance use

    J Dual Diagn

    (2012)
  • EJ Aspinall et al.

    Treatment of hepatitis C virus infection among people who are actively injecting drugs: a systematic review and meta-analysis

    Clin Infect Dis

    (2013)
  • GJ MacArthur et al.

    Opiate substitution treatment and HIV transmission in people who inject drugs: systematic review and meta-analysis

    BMJ

    (2012)
  • E V Griffiths et al.

    A systematic review of psychotropic drug prescribing for prisoners

    Aust NZ J Psychiatry

    (2012)
  • SD Ryder

    Chronic hepatitis C-what do the new drugs offer and who should get them first?

    Clin Med

    (2015)
  • GE Hunt et al.

    Psychosocial interventions for people with both severe mental illness and substance misuse

    Cochrane Database Syst Rev

    (2013)
  • WP Knapp et al.

    Psychosocial interventions for cocaine and psychostimulant amphetamines related disorders

    Cochrane Database Syst Rev

    (2007)
  • AE Perry et al.

    Interventions for drug-using offenders with co-occurring mental illness

    Cochrane Database Syst Rev

    (2015)
  • NA De Witte et al.

    Treatment for outpatients with comorbid schizophrenia and substance use disorders: a review

    Eur Addict Res

    (2014)
  • L Dutra et al.

    A meta-analytic review of psychosocial interventions for substance use disorders

    Am J Psychiatry

    (2008)
  • M Prendergast et al.

    Contingency management for treatment of substance use disorders: a meta-analysis

    Addiction

    (2006)
  • NS Farronato et al.

    A systematic review comparing cognitive-behavioral therapy and contingency management for cocaine dependence

    J Addict Dis

    (2013)
  • M Cleary et al.

    Psychosocial treatments for people with co-occurring severe mental illness and substance misuse: systematic review

    J Adv Nurs

    (2009)
  • NK Lee et al.

    A systematic review of cognitive and behavioural therapies for methamphetamine dependence

    Drug Alcohol Rev

    (2008)
  • A Zgierska et al.

    Mindfulness meditation for substance use disorders: a systematic review

    Subst Abus

    (2009)
  • Cited by (0)

    View full text