Homelessness is one of the more visible consequences of the nexus of unemployment, poverty, and a lack of affordable housing (Martin, 2015). Homelessness is an issue of national concern, with numerous federal agencies, nonprofit organizations, and the philanthropic community working to develop and implement programs that address this critical political-economic and public policy challenge (Farrugia and Gerrard, 2015; Harris, 2016).
In 1988, the Institute of Medicine (IOM) published Homelessness, Health, and Human Needs, which analyzed the scientific evidence regarding the causes and consequences of homelessness and associated health problems. The report noted that “the fundamental problem encountered by homeless people—lack of a stable residence—has a direct and deleterious impact on health. Not only does homelessness cause health problems, it perpetuates and exacerbates poor health by seriously impeding efforts to treat disease and reduce disability” (IOM, 1988, p. 141). Cited by practitioners and policy makers in the field as being foundational to their work, the report outlined federal action to improve health services, housing, and income levels to reduce homelessness (Jones, 2015). Nearly 30 years later, although progress has been made, homelessness continues to be an important challenge, particularly in urban areas. Revisiting the housing and health care needs of individuals experiencing homelessness is critical to moving the discussion forward and improving health outcomes for this population.
RELATIONSHIP BETWEEN HOUSING, HOMELESSNESS, AND HEALTH
The relationship between housing and health is complex. The idea that housing can impact health has been supported by a number of organizations, including the National Academies of Sciences, Engineering, and Medicine (NASEM, 2016), the Robert Wood Johnson Foundation (RWJF, 2015), and the Department of Health and Human Services (HHS). For example, in 2010, the HHS launched Healthy People 2020, a science-based 10-year agenda for “improving the Nation’s health.” The agenda includes discussion of the five social determinants of health, which include economic stability, education, health and health care, neighborhood and built environment, and social and community context
(HHS, 2018b). It describes housing instability as “a key issue in the Economic Stability domain” and observes that
housing instability has no standard definition. It encompasses a number of challenges, such as having trouble paying rent, overcrowding, moving frequently, staying with relatives, or spending the bulk of household income on housing. These experiences may negatively affect physical health and make it harder to access health care (HHS, 2018a).
In addition to the 2010 HHS report, the Bipartisan Policy Center issued a report in 2018 on “HHS Partnerships: A Prescription for Better Health,” which emphasizes the importance of partnerships between HHS and HUD to improve health. According to this report,
housing needs, left unaddressed, are a strain on our health care system. For example, the top 5 percent of hospital users—overwhelmingly poor and housing insecure—are estimated to consume 50 percent of health care costs. As such, many in the health care sector—including payers, hospitals, and clinicians—are increasingly seeing the potential of the home as a platform for health and wellness services and as an essential tool in chronic care management. We also know now that expenditures to improve access to safe, affordable housing can materially improve population health. Studies have clearly demonstrated the positive health effects of many housing-based interventions, including those, for example, that improve insulation and energy efficiency, provide greater accessibility, reduce mold and dampness, eliminate pest infestations, and abate lead (BPC, 2018, p. 5).
Internationally, the World Health Organization (WHO) defined health broadly in in its 1948 constitution as “a state of complete physical, mental, and social well-being and not merely the absence of disease or infirmity,” which implies an affiliation between housing and health.
The lack of housing has been associated with reduced opportunities for education, reduced food security, and reduced public safety (Baggett et al., 2013). Homelessness is linked to and exacerbates serious health conditions, including cardiovascular disease, diabetes, and HIV/AIDS, and adults living on the streets have shorter life expectancies (Baggett et al., 2013; Bowen, 2016). In addition, the prevalence of mental illness and substance use along with co-occurring chronic health conditions is significantly higher for some homeless populations, which has implications for the delivery and cost of services (Martin, 2015). Health problems can also cause homelessness; for example, mental illness, substance use, and chronic illness, have been cited as causative of homelessness (IOM, 1988). Furthermore, individuals who experience homelessness are more likely to rely on emergency health care services, experience a lack of health coverage, and experience a lack of access to ambulatory clinics that are able to meet their needs. This
In 1988, it was estimated that 735,000 people experienced homelessness on any given night, although estimates ranged from 250,000 up to 2.2 million (IOM, 1988). In 2017, although the estimate remained high, the numbers had decreased to just more than 550,000 people staying in shelters or in places not intended for human habitation on a single night (HUD, 2017b). Many more people experience homelessness over longer periods, such as 1 year or more. In 2016 (the last data available), 1.42 million people stayed in a homeless shelter or a transitional housing program (HUD, 2017a).
Although the numbers have improved since 2010, homelessness remains a significant problem for those who experience it (HUD, 2017a). Consequently, a wide range of housing and other services has been developed to address the needs of individuals experiencing homelessness. Permanent supportive housing (PSH), defined in the Statement of Task for this study as “decent, safe, and affordable community-based housing that provides residents the rights of tenancy under state and local landlord-tenant laws,”1 is an example of a specific type of program designed to keep individuals experiencing chronic homelessness stably housed (Baker and Evans, 2016). In this type of housing, tenants have a private and secure place to make their home with the same rights and responsibilities as other community members. Tenants have access to the support services that they need and want to use, and they can remain in their homes as long as they meet the basic obligations of tenancy, such as paying reduced or subsidized rent.
Not all individuals experiencing homelessness need PSH. Although HUD prioritizes those with chronic homelessness for PSH (HUD, 2016a), generally, eligibility is based on long-term disability status, experiences with homelessness or unstable housing, or experiences of multiple barriers in maintaining housing stability. Program eligibility is in part dependent on the available funding stream (e.g., U.S. Department of Veterans Affairs funds can only be used to provide PSH to veterans and their families). To facilitate eligibility for receiving this housing, HUD has developed a definition of chronic homelessness (HUD, 2015c):2
- A “chronically homeless” individual is defined to mean an individual experiencing homelessness with a disability who lives either in a place not meant for human habitation, a safe haven, or in an emergency shelter, or in an institutional care facility if the individual has been living in the facility for fewer than 90 days and had been living in a place not meant for human habitation, a safe haven, or in an emergency shelter immediately before entering the institutional care facility. To meet the “chronically homeless” definition, the individual also must have been living as described above continuously for at least 12 months, or on at least four
1 The committee agreed upon a slightly different definition from that in the Statement of Task.
2 The HUD definition above was the definition used by the committee.
separate occasions in the last 3 years, where the combined occasions total a length of time of at least 12 months. Each period separating the occasions must include at least 7 nights of living in a situation other than a place not meant for human habitation, in an emergency shelter, or in a safe haven.
- Chronically homeless families are families with adult heads of household who meet the definition of a chronically homeless individual. If there is no adult in the family, the family would still be considered chronically homeless if a minor head of household meets all the criteria of a chronically homeless individual. A chronically homeless family includes those whose composition has fluctuated while the head of household has been homeless.
- An individual experiencing homelessness who is (a) without a home and living in a short-term emergency shelter or somewhere not intended for human habitation (e.g., an abandoned building, on the street, in an automobile); (b) has lived in such a setting continuously for at least a year or on at least four different occasions over a 3 year period; and (c) is or could be diagnosed with any of the following: substance use disorder, post-traumatic stress disorder, traumatic brain injury, chronic illness or disability, developmental disability, or serious mental illness.
- The definition also includes individuals previously residing (for less than 90 days) in an institutional care facility such as a jail, mental health treatment facility, hospital, or similar facility, as long as they meet the criteria in the first bullet prior to entering the facility.
- A family experiencing homelessness with an adult head-of-household who meets the criteria in the first bullet above.
The number of individuals experiencing chronic homelessness is difficult to estimate; however, the 2016 Annual Homeless Assessment Report (AHAR) to Congress estimated that more than 77,000 individuals experiencing homelessness on a specific night in January 2016 were defined as being chronically homeless (HUD, 2016c). Although people experiencing chronic homelessness are but one subpopulation of individuals experiencing homelessness, they are the primary population of interest in this report.
COMMITTEE’S STATEMENT OF TASK
In 2016, a number of foundations and organizations came together to support a study to be conducted by the Science and Technology for Sustainability program, in collaboration with the Board on Population Health of the National Academies of Sciences, Engineering, and Medicine (National Academies) to address a fundamental question: To what extent have permanent supportive housing
programs improved health outcomes and affected health care costs in people experiencing homelessness? More specifically, the committee focused on the following questions:
- What is the evidence that permanent supportive housing improves health-related utilization and outcomes in homeless persons with serious, chronic, or disabling conditions (e.g., substance use disorders, serious mental illness, physical disabilities, diabetes, etc.)? How cost-effective is PSH for addressing homelessness and health outcomes compared with usual care and alternative interventions?
- What are individual and other characteristics that may be associated with the health-related outcomes and costs of permanent supportive housing (e.g., age, health conditions, other demographics)?
- What characteristics of permanent supportive housing programs, if any, result in improved health outcomes and evidence of cost-effectiveness?
- How generalizable are the findings from studies evaluating outcomes associated with the use of permanent supportive housing in the chronically homeless to other homeless populations (families with children, disabled persons, etc.)?
- Are the outcomes associated with the use of permanent supportive housing translatable to other populations or systems (e.g., what are common characteristics that might translate to an institutionalized population)?
- What are the key policy barriers and research gaps associated with developing programs to address the housing and health needs of homeless populations?
COMMITTEE’S APPROACH TO THE TASK
To respond to this task, the National Academies convened the Committee on an Evaluation of Permanent Supportive Housing Programs for Homeless Individuals in April 2016 to conduct the study and prepare this report. The committee includes 11 experts with research or expertise in a broad range of areas including homelessness policy, social science, health care, health care administration, population health, health disparities, health care cost-effectiveness, housing policy, urban sustainability, urban poverty, health economics, and statistics. Brief biographies of committee members and the study staff are provided in Appendix A.
In addition to reviewing the relevant literature, the committee held four meetings over an 18-month period, to obtain input from an array of experts and stakeholders. The committee also conducted site visits in Denver, Colorado, and San Jose, California, to see PSH in the community and to obtain direct input from housing providers and nongovernmental organizations. These information-gathering activities informed the committee’s discussions and the final report. In conducting its work, the committee grounded its review on three sets of findings:
- The IOM’s 1988 finding that the lack of stable housing has a direct and deleterious impact on health (IOM, 1988);
- WHO’s broad notion of health, and the role of housing as an influencer of health (WHO, 1994); and
- The National Academies report findings reiterating that housing is a social determinant of health (NASEM, 2016, 2017).
Because PSH is primarily directed to individuals who experience chronic homelessness, this subpopulation of individuals experiencing homelessness is the primary focus of this report.
Limitations of the Evidence
The committee’s deliberations were limited by a less than robust literature and evidentiary base to assess the effect of individual and program characteristics on outcomes in permanent supportive housing. The committee was disappointed to find that the existing literature lacks information on the type, intensity, frequency, or length of the needed services, as well as a lack of clear details of what constitutes “usual services” when comparing the efficacy of different models of permanent supportive housing. The lack of data about these things effectively precluded generalizing to who among individuals experiencing homelessness are most likely to benefit from the services and different models of PSH.
The committee also identified inconsistencies in definitions and characteristics of PSH, and limited understanding of key services or minimum standards of PSH. The evidentiary base for screening tools used in allocating housing services assistance is especially limited. These limits create barriers to the collection of data on health outcomes of persons utilizing PSH. Further, data systems are not currently designed to integrate homeless, health, and other data resources, which limited the ability of the committee to draw conclusions on these connections. Regarding its evaluation on the literature of cost-effectiveness of PSH, the committee notes that while many studies that have applied a pre-test/post-test design have shown marked cost reductions, the few carefully conducted randomized controlled trials that have been done have failed to show any significant reduction in costs or improvements in health.
The committee was able to conclude less than it had expected would be possible when embarking on its work, because of the many evidentiary shortcomings. The findings and recommendations highlight what additional research is needed to determine the effectiveness of PSH in addressing health outcomes and to clarify for whom and in which circumstances it may be most beneficial.
ORGANIZATION OF THE REPORT
This chapter provides a brief overview of the committee’s approach. Chapter 2 describes the extent and burden of homelessness and elaborates on the programs and approaches used to address it. Chapter 3 evaluates evidence on the efficacy of permanent supportive housing on health. Chapter 4 examines the cost-effectiveness of permanent supportive housing on health. Chapter 5 describes the effect of individual and program characteristics on the outcomes of permanent supportive housing. Chapter 6 explores the impact of these programs on families and youth. Chapter 7 details program and policy barriers to establishing and financing PSH programs. Chapter 8 addresses research gaps. Finally, Chapter 9 offers the committee’s concluding observations and recommendations.