Comparative Effectiveness of Single-Site and Scattered-Site Permanent Supportive Housing on Patient-Centered and COVID-19-Related Outcomes for People Experiencing Homelessness, California, 2021-2023

People experiencing homelessness (PEH) were among the most likely to contract the novel coronavirus disease 2019 (COVID-19). Many PEH utilized high-density public places to satisfy their basic needs (e.g., soup kitchens for sustenance, public libraries for restrooms). This made it difficult for them to limit close contact with others and put them at increased risk of contracting and transmitting COVID-19. Furthermore, it was difficult to follow recommended protective measures--such as handwashing and social distancing--when living in shelters or on the streets.
PEH were at higher risk of COVID-19 related hospitalization and death than the rest of the population. The poor living conditions of PEH accelerated aging, leading them to experience geriatric conditions and medical complications more typical of individuals 10-20 years older. They were also at increased risk of cardiovascular and respiratory disease, HIV/AIDS, and diabetes, all conditions that increase vulnerability to serious COVID-19-related complications and death. These risks were compounded by the fact that PEH also faced significant barriers to accessing quality health care. In the absence of protective action, it was estimated that more than 21,000 PEH would require hospitalization due to COVID-19, more than 7,000 would require critical care, and nearly 3,500 would die.
Consequently, the COVID-19 pandemic made housing and health care for PEH one of the top priorities for the U.S. health care and public health systems. State and local governments across the country used federal relief funds to allocate private hotel rooms as protective shelter for vulnerable PEH. In Los Angeles County (LAC), which contains the largest unsheltered homeless population in the nation, 2,400 PEH were placed in hotels. COVID-19 response plans included accommodating up to 15,000 PEH in hotels who would then be moved to permanent housing in 90 days. This rapid push into housing amid a pandemic necessitated a delicate balance between social distancing and maintaining patients' basic needs, continuity of existing care, and personal and social well-being.
Permanent supportive housing (PSH)--programs that provide immediate access to independent living situations coupled with support services--is the most effective approach for serving PEH. Numerous studies have demonstrated PSH's effectiveness in improving housing retention, quality of life, and HIV outcomes. Though evidence concerning its impact on other health outcomes, health behaviors, and health care utilization is limited, the National Academies of Sciences, Engineering, and Medicine has nonetheless recognized PSH as extremely beneficial for PEH's health. COVID-19 was what this organization termed a "housing-sensitive condition"--one whose transmissibility, course, and medical management are particularly influenced by homelessness. Consequently, the National Alliance to End Homelessness recommended the use of PSH as part of its framework to address COVID-19 and homelessness.
However, significant questions remain about what types of PSH programs can best address COVID-19-related risk and promote patient-centered outcomes at a time of social and community disruption. There are two distinct approaches to implementing PSH: place-based (PB) PSH, or single-site housing placement in a congregate residence with on-site services, and scattered-site (SS) PSH, which uses apartments rented from a private landlord to house clients while providing mobile case management services. The strengths and weaknesses of these two approaches remain largely unknown but may have direct implications for adherence to COVID-19 prevention protocols and other health-related outcomes.