. 2016 Jan;106(1):e1–e23. doi: 10.2105/AJPH.2015.302905

TABLE 2—

Characteristics of Longitudinal Studies With Health, Medical Care, Adherence, and Risk Behavior Outcomes: 1996–2014

Study and Location	Focus	Study Design and Sample	Housing Measures	Outcomes	Main Housing-Related Findings^a
RCT housing interventions: multiple outcomes
Wolitski et al.²⁶; Baltimore, MD; Chicago, IL; Los Angeles, CA	To assess the effects of permanent rental housing assistance on the health and risk behaviors of homeless and unstably housed PWH	RCT of housing intervention Convenience sample recruited by agencies providing housing assistance and social services to PWH	In past 90 d: homeless ≥ 1 nights: slept in shelter or places not suitable for human habitation; unstably housed: temporarily doubled up with others, lived in a transitional or transitory setting; stable housing: had own place, a room, apartment, or house that is your home	HIV clinical health Other health outcomes Medical care ED and inpatient use Risk behaviors	Improved housing status resulted in substantial reductions in medical care utilization and improvements in self-reported physical and mental health functioning; significant differential change benefiting the intervention group for mental health indicators Significant differences between homeless and stably housed participants found in as-treated analyses for ED use, mental health, and detectable viral load
Buchanan et al.²⁹; Chicago	To determine the health benefits of permanent supportive housing among homeless persons hospitalized with a chronic medical illness	RCT of housing intervention convenience sample from the inpatient medical and surgical service	Homeless: no source of stable housing (with no time limits, for which the person has adequate resources) at hospital discharge and during 30 d before admission	HIV clinical health	At 12 mo, intervention group significantly more likely to be alive with intact immunity, with significantly lower median viral loads
Longitudinal design: HIV health care access and utilization and ED and inpatient use
Muthulingam et al.⁷¹; San Francisco, CA	To measure sociodemographic and risk disparities in timely linkage to care, retention in care, and viral suppression among persons with HIV	Prospective cohort study Surveillance data from San Francisco Department of Health	Housing status: homeless, not homeless, unknown at HIV diagnosis; homelessness noted on medical record or address was homeless shelter, a health clinic, or free postal address not connected to a residence	HIV medical care HIV clinical health	Unknown housing status at diagnosis associated with lower rates of linkage to care; homelessness and unknown housing status independent predictors of failure to achieve viral suppression 12 mo after diagnosis
Weiser et al.⁷²; San Francisco	To examine the association between food insecurity and health care utilization, hospitalizations, and ED visits, among homeless and marginally housed PWH	Prospective cohort study Probability sampling from homeless shelters, free food programs and SROs in 3 low-income neighborhoods	Homeless: slept on the street or in a homeless shelter in the past 90 d	ED and inpatient use	Homelessness significantly associated with hospitalization in the unadjusted model and significantly associated with ED use in both unadjusted and adjusted models
Fairbairn et al.⁷⁵; Vancouver, BC	To examine prevalence and correlates of ED use, ED diagnoses, and hospital admission rates among HIV-positive IDUs	Prospective cohort study Convenience sample recruited in a low-income central city neighborhood through word of mouth and street outreach	Unstable housing: SRO hotel, shelter, recovery or transition house, jail, on the street, or having no fixed address	ED and inpatient use	Living in unstable housing independently associated with higher cumulative incidence rate of ED use and shorter time to first ED visit during the study period
Knowlton et al.⁵²; Baltimore; Miami, FL; New York City; San Francisco	To identify multilevel factors associated with HAART use among a community sample of active IDUs recruited from US urban epicenters	Prospective cohort study Convenience sample active and passive recruitment at AIDS service organizations, medical clinics, methadone clinics, homeless shelters, and street-based settings	Stable housing: self-report currently has a place to stay 5–7 d/wk	HIV medical care	Participants with stable housing had double the odds of HAART use than did those without stable housing
Arnold et al.⁴⁶; San Francisco	To assess the role of neighborhood socioeconomic context on racial/ethnic disparities in ART initiation and AIDS survival	Prospective cohort study HIV surveillance data reported to San Francisco Department of Health 1996–2001 followed through 2006	Homeless: at the time of HIV diagnosis homelessness noted on medical record or address was homeless shelter, a health clinic, or free postal address not connected to a residence	HIV medical care HIV clinical health (mortality)	Homeless at time of AIDS diagnosis significantly associated with being uninsured; homelessness at diagnosis had an independent effect on delayed or no ART initiation, controlling for neighborhood socioeconomic context Homelessness associated with mortality within 30 d of AIDS diagnosis; excluding persons who died within 30 d, homeless at diagnosis not associated with 5-year survival
Gardner et al.⁴⁹; Atlanta, GA; Baltimore; Los Angeles, Miami	To identify demographic, structural, behavioral, and psychological subgroups for whom intervention had differential effects in linking PWH to care	Pre–post intervention study of linkage to care intervention Convenience sample recruited from sexually transmitted disease clinics, hospitals, and community-based organizations	Unstable housing: on the street, in shelter, or other temporary housing, in an institution (treatment facility, halfway house, group home, hospital or nursing home); stable housing: in a house or apartment alone or with others	HIV medical care	PWH with unstable housing at baseline were less likely than were those with stable housing to link with HIV primary care In multivariate analysis of effect modification, intervention had a stronger effect on linkage to primary care for unstably housed participants than for stably housed
Aidala et al.¹⁷; New York City	To examine housing and connection to care in a probability sample of PWH tracking housing status and medical care utilization over an extended period	Prospective cohort study Multistage probability sampling using sequential enrollment or list-based systematic random sampling of clients from a stratified sample of medical and social service agencies	Homeless: sleeping on the street, drop-in center, shelter, SRO, place not meant for sleeping Unstably housed: transitional housing, jail, treatment facility doubled up; stably housed: permanent housing in own house or apartment; housing assistance: receipt of rental or other direct housing assistance; housing need: homeless, unstably housed, need assistance to maintain housing	HIV medical care	PWH who are homeless, unstably housed, or with other housing needs significantly less likely to have received HIV medical care; receipt of housing assistance significantly increases the odds of visits for HIV care Analysis over time shows housing needs are associated with lack of continuity of HIV care; receipt of housing assistance predicts retention in care Among PWH unconnected to HIV care, those who have housing needs are half as likely to enter care within 12 mo; receipt of housing assistance predicts transition into care
Nosyk et al.⁸³; Vancouver	To determine the effect of homelessness and neighborhood SES on hospitalization patterns and costs in patients with HIV and AIDS	Retrospective cohort study Recruitment method: convenience sample of hospitalized PWH patients residing in downtown Vancouver, Canada	Homeless: patients without a fixed address during ≥ 1 admissions within a particular calendar year; DTES: patients with a fixed address within the most impoverished neighborhood in a particular calendar year	ED and Inpatient Use	Homeless patients had more ED admissions; homeless males had longer length of hospital stay and homeless IDUs had more hospitalization than did PWH in high SES neighborhoods PWH residing in the low-SES neighborhood had more ED admissions, and males had longer length of hospital stay than did PWH living in high SES neighborhoods
Rumptz et al.⁴²; 10 US urban centers	To examine factors associated with engaging socially marginalized PWH in primary care	Pre–post intervention study Convenience sample of participants in 10 urban interventions to improve primary care engagement; recruited via outreach and referral from service providers	Housing arrangements in previous 6 mo: own home or apartment, someone else’s home, or temporary arrangement; unmet needs for housing: not otherwise defined	HIV medical care	PWH with unmet needs for housing less likely to improve engagement with HIV primary care in bivariate analysis Decrease in composite measure of unmet needs (including housing needs) significantly associated with improved engagement with care in multivariate models
Wilkinson et al.⁴⁴; Baltimore, Miami, New York City, San Francisco	To identify factors associated with medical care utilization by IDUs PWH participating in adherence and risk reduction intervention	Prospective cohort study Convenience sample using active and passive recruitment at AIDS service organizations, medical clinics, methadone clinics, and street-based settings	Stable housing: self-report has a place to stay 5–7 d/wk	HIV medical care ED and inpatient use	Obtaining or maintaining stable housing associated with using an outpatient setting rather than the ED as the usual source of care at 12-mo follow-up
Kim et al.³⁷; Boston, MA	To examine whether episodes of homelessness are independently associated with suboptimal medical utilization among problem alcohol users	Prospective cohort study Convenience sample of PWH with alcohol problems indicated by screener questionnaire or physician assessment, recruited from HIV primary care and specialty clinics	Homelessness Self-report of any night spent on the street or in a shelter in the past 6 mo	HIV medical care ED and inpatient use	No significant difference found in primary care visits between homeless and housed periods in longitudinal regression model Homelessness significantly associated with higher ED utilization rates and rates of inpatient hospitalization Length of time homeless associated with higher utilization of both ED and inpatient hospitalization
Kushel et al.³⁸; San Francisco	To determine if case management associated with acute medical care use and improved clinical outcomes in homeless and marginally housed PWH	Prospective cohort study Probability sampling from homeless shelters, free food programs and SROs in 3 low-income neighborhoods	Marginally housed: at least 90% of nights spent in a residential hotel or an apartment; homeless: < 90% of nights spent in a residential hotel and ≥ 1 nights slept on the street or in a shelter, in the past 90 d	HIV medical care ED and inpatient use Adherence HIV clinical outcomes	Homelessness negatively associated with receipt of routine primary care in bivariate but not full adjusted models No difference in the uniformly low rates of viral suppression among marginally housed and homeless participants
Palepu et al.³²; Boston	To examine the association of substance abuse treatment services with hospitalization among PWH with a history of alcohol problems	Prospective cohort study Convenience sample of PWH screening positive for alcohol problems; recruited from medical settings serving PWH, including respite care facility	Homeless: ≥ 1 nights on the street or in a shelter in the past 6 mo	HIV medical care ED and inpatient use	Rates of hospitalization higher among homeless PWH with alcohol problems Recent homelessness significantly increased odds of hospitalization in longitudinal analysis
Masson et al.³⁰; San Francisco	To examine factors affecting medical service use among PWH with substance abuse disorder	Prospective cohort study: pooled data from RCT case management intervention study Targeted and purposive recruitment from ED, inpatient wards, and outpatient detox clinic of a public hospital	Current living situation: homeless: living in a shelter, car or outdoors; institution: such as jail or hospital Room in a hotel or motel; halfway house or residential treatment; house or apartment of a friend or relative; house or apartment you rent or own	HIV medical care ED and inpatient use	Homelessness associated with significantly higher utilization of both ED and inpatient services among PWH with a substance abuse disorder
Messeri et al.²⁹; New York City	To examine the impact of nonmedical supportive services on engagement with HIV medical care	Prospective cohort study Multistage probability sampling using sequential enrollment or list-based systematic random sampling of clients from a stratified sample of medical and social service agencies	Housing need: self-report experienced housing problems or need for assistance with housing in past 6 mo; housing services: received help or assistance with housing in past 6 mo	HIV medical care	Housing services have a weak positive effect on entry into any medical care but none on entry into appropriate HIV care Individuals who receive housing services are more than twice as likely to retain appropriate medical care as those not receiving housing services
Longitudinal design: ART adherence
Weiser et al.⁶⁶; San Francisco	To examine food insecurity and HIV outcomes in a longitudinal study of marginally housed PWH	Prospective cohort study Probability sampling from homeless shelters, free food programs, and SROs in 3 low-income neighborhoods	Homeless: sleeping on the street or in a shelter in the past 90 d	ART adherence HIV clinical health	Recent homelessness was associated with less than optimal adherence and having a detectable viral load
O’Neil et al.¹³⁴; BC	To determine factors associated with adherence among PWH receiving ART therapy	Prospective cohort study Convenience sample recruited through providers, community advertising, and referral	Unstable housing: living in a SRO hotel, shelter, hostel, treatment center or prison, or having no fixed address	ART adherence	PWH with optimal adherence more likely to be stably housed, but housing status not a significant predictor of ART adherence in adjusted models
Roux et al.⁶⁷; 17 outpatient hospital services in France	To investigate the relationship between initiating HCV treatment and ART adherence HIV and HCV coinfected patients	Prospective cohort study Convenience sample of PWH recruited in outpatient hospital services delivering HIV and HCV care in France	Good housing conditions: participant answered “quite comfortable” or “very comfortable” vs “uncomfortable” or “very uncomfortable” housing conditions	ART adherence	Good housing conditions were associated with reduced risk of nonadherence to ART, regardless of treatment of HCV
Milloy et al.⁵⁸; Vancouver	To investigate the impact of homelessness on viral suppression among illicit drug users initiating ART in a setting with universal access to HIV care	Prospective cohort study HIV-positive illicit drug users recruited via outreach and snowball sampling from street and service settings in a disadvantaged urban neighborhood	Homelessness: living on the street with no fixed address at any time in the past 6 mo	ART adherence HIV clinical health	Homelessness independently associated with lower levels of ART adherence Homelessness significantly associated with lower likelihood of achieving viral suppression and with longer time to viral suppression after initiation of treatment
Milloy et al.⁵⁸; Vancouver				Palepu et al.⁸⁵; Vancouver	To determine the longitudinal impact of homelessness on adherence to ART therapy	Retrospective cohort study Snowball sample of IDUs recruited through street outreach	Homelessness: living on the street or no fixed address in the past 6 mo	ART adherence	Homelessness significantly negatively associated with ART adherence
Kalichman et al.⁵⁶; Atlanta	To examine the association of social, health, and poverty-related stressors on ART adherence in PWH with low literacy	Prospective cohort study Convenience sample recruited through service organizations, health care providers, and word of mouth	Housing poverty experience: worried about having a place to stay; poverty experiences: sum of poverty-related stressors, including housing poverty	ART adherence	Poverty experiences significantly associated with poorer ART adherence in a group with low adherence rates; being worried about a place to stay not significantly associated with ART adherence as independent predictor
Lima et al.⁸⁴; BC	To determine the scale of regional migration and its association with ART adherence patterns over time	Retrospective cohort study Medical record review of all patients initiating ART therapy through regional HIV/AIDS treatment and medication distribution sites	Migration: cumulative number of residential address changes during course of HIV treatment	ART adherence	Migration was associated with nonadherence to ART; increase in number of address changes associated with greater odds of nonadherence
Kim et al.⁴¹; Boston	To investigate predictors of discontinuing ART in PWH with alcohol problems	Prospective cohort study Convenience sample recruited from health care centers, homeless shelters, drug treatment programs, community advertisements, and a previous study of PWH and alcohol problems	Homelessness: any night spent in a shelter or on the street in the past 6 mo	ART adherence	Homelessness predicts discontinued ART therapy in the unadjusted analysis; not significant in fully adjusted models
Berg et al.⁵³; New York City	To identify gender differences in social and behavioral factors, including drug or alcohol use associated with ART adherence	Prospective cohort study Convenience sample of current or former HIV-positive IDUs recruited from outpatient methadone-maintenance treatment program	Housing status: own apartment, other’s apartment, or temporary housing (in a hotel, motel, shelter, temporarily with someone, or being without shelter) long-term housing: in current residence ≥ 3 y	ART adherence	Lack of long-term housing stability was significantly associated with worse ART adherence for both men and women
Spire et al.⁵⁵; 47 locations in France	To analyze relationships between ART adherence and PWH characteristics and experiences before and after ART initiation	Prospective cohort study Convenience sample of PWH initiating an ART regimen 1997–1999, recruited from 47 clinical centers	Housing condition: self-report current housing unstable housing, stable but poor housing, or stable (adequate) housing	ART adherence	Both stably but poorly housed participants and unstably housed participants had higher risk of not adhering to ARTs than did PWH with stable, adequate housing
Longitudinal design: HIV clinical health outcomes
Anema et al.⁶⁴; BC	To assess the potential relationship between food insecurity and all-cause mortality among HIV-positive IDUs initiating ART in BC	Prospective cohort study Sample population of IDU, PWH initiating ART across BC 1998–2011	Unstable housing: living in a hotel, boarding house, group home, jail, on the street, or having no fixed address at the time of program entry	HIV clinical health (mortality)	No significant association between unstable housing at treatment program enrollment and all-cause mortality over median 133 y of follow-up
Fuster et al.⁷⁹; Boston	To assess association between HCV infection and overall and liver-related death in PWH with alcohol problems	Prospective cohort study Convenience sample recruited at HIV clinics, hospitals, and homeless and drug treatment programs	Homeless: ≥ 1 nights in a shelter or on the street 6 mo before assessment period	HIV clinical health (mortality) Other health	Recent homelessness associated with HCV infections among PWH with alcohol problems; homelessness not associated with all-cause mortality
Meyer et al.⁶⁰; 9-state multicenter study in US	To examine HIV treatment outcomes among PWH released from jail participating in care linkage intervention	Pre–post intervention study Convenience sample of PWH from 10 prisons taking part in intervention to transition from the jail to postrelease services	Homeless: self-report being homeless or sleeping in a shelter or public space 30 d before incarceration or 30 d before follow-up interview	HIV clinical health	Prejail homelessness inversely correlated with baseline viral load suppression; not significant in adjusted models; housing status not associated with viral load suppression at 6-mo postintervention follow-up
McMahon et al.⁶⁹; Boston; Providence, RI	To investigate whether SES predicts mortality in HIV-positive persons in the era of HAART	Prospective cohort study Convenience sample recruited through advertisements, posters, presentations at HIV organizations, primary care clinics, and public media	Homeless: no fixed and regular nighttime residence, sleeping in a shelter, welfare hotel, boarding house, or place not normally used for sleeping	HIV clinical health (mortality)	Homelessness independently associated with increased risk of mortality controlling for HIV disease markers
Schwarcz et al.⁸⁹; San Francisco	To examine the effect of homelessness on the mortality of persons diagnosed with AIDS and measure the effect of receipt of supportive housing on AIDS survival	Case–control study Public health department records identifying AIDS-diagnosed adults and adolescents 1996–2006; persons who entered a supportive housing program at any point after AIDS diagnosis	Homeless: address recorded in AIDS registry as homeless, a known homeless shelter, a medical care clinic, or a free postal address not connected to a residence; receipt of supportive housing: entry into supportive housing program	HIV clinical health (mortality)	Homelessness significantly increased the risk of death within 5 y of AIDS diagnosis Homeless persons with AIDS who obtained supportive housing had significantly lower risk of death than did those who did not
Oppenheimer⁵⁰; Austin, TX	To examine the effect of demographics, stress, coping strategies, and clinical medical support on HIV progression	Prospective cohort study Convenience sample of patients visiting a publicly funded HIV/AIDS treatment clinic	Housing status: currently having a home: renting or owning a home or staying with family or friends; vs not having a home (homeless)	HIV clinical health	Homelessness significantly negatively correlated with CD4 count over 15 mo Homelessness the only significant predictor of decrease in CD4 over time among patients with inconsistent clinic visits
Walley et al.⁴⁵; Boston	To assess the impact of recent heavy alcohol use, heroin or cocaine use, and homelessness on short-term mortality in PWH with alcohol problems	Prospective cohort study Convenience sample recruited by multiple methods from service sites and community referral	Recent homelessness: ≥ 1 nights in an overnight shelter or on the street in the past 6 mo	HIV clinical health (mortality)	Over a 10-y period, recent homelessness significantly associated with increased risk of short-term mortality among PWH with current or past alcohol problems
Miller et al.⁸²; BC	To provide a profile of Aboriginal people initiating ART and their response to treatment	Retrospective cohort study Convenience sample identified through Medical records review of all patients initiating ART therapy through regional HIV treatment sites who completed a baseline survey	Unstable housing: living in a hotel, jail, boarding house, group home, on the street, or having no fixed address at time of ART initiation	HIV clinical health	PWH with unstable housing at baseline were less likely to achieve viral suppression
Riley et al.³⁴; San Francisco	To estimate mortality rates and examine the effect of sustained treatment exposure on survival rates of homeless or marginally housed PWH	Prospective cohort study Probability sampling from homeless shelters, free food programs, and SROs in 3 low-income neighborhoods	Currently homeless: spend most nights on the street or in a shelter; lifetime homeless experience: homeless > 1 y as an adult	HIV clinical health (mortality)	There were no differences in risk of death within 6 y between those who were homeless at baseline and the unstably housed; lifetime homeless experience was not associated with increased mortality risk Sustained ART treatment significantly reduced the risk of death regardless of recent or lifetime homeless experience
Lieb et al.⁹⁰; 4 Florida cities	To evaluate modifiable factors associated with HIV/AIDS mortality in a nonresearch setting	Case–control study Statewide HIV/AIDS reporting system and medical records used to identify all PWH treated at 4 health clinics who died during 1999, and control participants randomly selected from other PWH seen at the clinics	Housing status; medical record indicates homelessness on the basis of description of living situation during the 1-y period before last clinic visit	HIV clinical health (mortality)	Recent homelessness an independent predictor of mortality among PWH In multivariate model with treatment variables and behavioral factors related to treatment, homelessness increased risk of mortality almost 10-fold
Longitudinal design: other health outcomes
Rourke et al.⁵⁹; ON	To examine the relationship between material, meaningful, and spatial dimensions of housing and health-related quality of life among adult PWH	Prospective cohort study Stratified purposive recruitment through community-based AIDS service organizations, including efforts to locate and recruit PWH not in services	Homelessness: emergency shelter, living in a car, on the streets, or couch surfing; inadequate housing: motel, hotel, or boarding house	Other health outcomes: Physical and mental health functioning; quality of life	Baseline housing and neighborhood variables associated with physical and mental health quality of life Difficulty paying housing costs associated with worse mental health over time Satisfaction with housing associated with improved mental health score
Riley et al.⁵⁷; San Francisco	To identify and empirically rank factors that longitudinally affect the physical and mental health status of HIV-positive homeless and unstably housed women	Prospective cohort study Probability time and location sampling by a mobile outreach team at homeless shelters, free food programs, and low-income hotels	In prior 90 d: homeless: slept on the street or in shelter; unstably housed: slept in SRO hotel or other marginal housing; unmet subsistence needs: composite measure includes difficulty with a place to sleep	Other health outcomes: Physical and mental health functioning; gynecological symptoms	Homelessness significantly associated with worse mental health functioning Unmet subsistence needs had the strongest effect on mental health, gynecologic symptoms, and overall physical health functioning in adjusted models
Popovich et al.⁸⁸; Chicago	To assess population-level incidence of HIV+ patients with community-associated methicillin-resistant CA-MRSA	Case–control study Identification of cases and controls using electronic data from all patients receiving medical care in a multicenter regional safety net hospital and ambulatory care system	Alternative housing: Current residence in subsidized housing, shelters, or substance abuse centers	Other health outcomes: CA-MRSA	Residence in alternative housing (shelters) independently associated with increased risk of CA-MRSA among PWH
Chin et al.⁴⁷; New York City	To examine the impact of substance use status, ART treatment status, and housing stability on physical and mental health–related quality of life	Prospective cohort study Sequential enrollment of participants in social service intervention programs over a 5-y period	Unstably housed: homeless, living in a residential or SRO hotel, shelter, or emergency housing Stably housed: rent or own an apartment or home, live with family or friends, or reside in HIV housing	Other health outcomes: Physical and mental health functioning; quality of life	Consistently unstable housing or change from stable to unstable housing associated with lower quality of life scores Change in housing status from unstable to stable housing associated with improved physical and mental quality of life scores but not statistically significant in full adjusted models
Mrus et al.³⁹; Cincinnati, OH; Pittsburgh, PA; Washington, DC	To compare health-related quality of life and predictors of quality of life among PWH receiving care in VA settings and non-VA settings	Prospective cohort study Convenience sample of patients visiting HIV outpatient clinics at 4 sites in 3 cities	Unstable housing: self-report housing situation as “transient and live in shelter” or “homeless” among other housing options	Other health outcomes: Quality of life	Stable housing significantly associated with better self-reported health status at baseline and with indicators of better health quality of life in longitudinal analysis
Hall et al.⁵⁴; San Francisco	To investigate HCV prevalence, incidence, and treatment in an HIV-positive cohort of the urban poor	Prospective cohort study Probability sampling from homeless shelters, free food programs and SROs in 3 low-income neighborhoods	Recently homeless: spent a night on the street or in a shelter in the past 30 d; lifetime homeless experience: total time homeless > 1 y	Other health outcomes: HCV	Lifetime homeless experience significantly associated with baseline HCV-positive status Lifetime or recent homeless experience not associated with incident HCV infection during follow-up period
Longitudinal studies: HIV risk behaviors
Cox et al.⁶³; Canada	To examine the occurrence of drug use cessation and its correlates in a Canadian cohort of HIV–HCV coinfected drug users	Prospective cohort study Convenience sample of HIV–HCV coinfected IDUs or crack users, recruited from existing clinic populations	Unstable housing: not having a fixed address (a personal address where mail can be delivered)	Risk behaviors Drug use	Cessation of drug use was significantly more likely among participants with a fixed address
Krishnan et al.⁶¹; CT, GA, IL, MA, NY, OH, PA, RI, SC	To examine substance abuse outcomes among a large cohort of HIV-infected jail detainees after release	Pre–post intervention study Convenience sample of PWH from 10 prisons taking part in intervention to transition from the jail to postrelease services	Homeless: self-report being homeless or sleeping in a shelter or public space 30 d before incarceration; or 30 d before follow-up interview	Risk behaviors Drug use	PWH who were homeless 30 d before incarceration were significantly more likely to use cocaine after release than were participants housed before incarceration PWH homeless at 6-mo follow-up were significantly more likely to use cocaine and opioids than were those stably housed
Vijayaraghavanet al.⁶⁵; San Francisco	To examine rates of and factors associated with opioid analgesic misuse in a community-sampled cohort of indigent adult PWH	Prospective cohort study Probability sampling from homeless shelters, free food programs and SROs in 3 low-income neighborhoods	Currently homeless: sleeping on the street or in a shelter in the past 90 d	Risk behaviors Drug use	In multivariate analysis, current homelessness was associated with opioid misuse
Zelenev et al.⁸⁰; CT, GA, IL, MA, NY, OH, PA, SC, RI	To examine correlates of homelessness and housing transitions and effect of housing status on HIV treatment outcomes	Pre–post intervention study Convenience sample of PWH from 10 prisons taking part in intervention to transition from the jail setting to postrelease services	Homeless: self-report being homeless or sleeping in a shelter or public space 30 d before incarceration or 30 d before follow-up interview	Risk behaviors Drug use Other health Health QOL HIV clinical health	Homelessness after incarceration was associated with higher odds of heroin, cocaine, and alcohol use and higher drug use and alcohol severity Homelessness after incarceration was associated with higher odds of depression and psychiatric severity and lower odds of physical and mental health quality of life PWH homeless at baseline less likely to have HIV provider, be on ART, or be adherent; individuals who were homeless at 6-mo follow-up had lower probability of being viral suppressed
Shannon et al.⁷⁶; Vancouver	Longitudinal examination of the impact of severe food insecurity on sexual risk taking among HIV-positive IDUs both on and not on HAART	Prospective cohort study Convenience sample of PWH recruited through snowball sampling and extensive street outreach methods in the city’s DTES (the drug use and HIV epicenter)	Homeless: living primarily on the streets or staying in SROs	Risk behaviors Sex behavior	Homelessness was not a significant predictor of unprotected sex
Aidala et al.³⁵; New York City	To examine overtime patterns of sexual behavior and sexual risk among a large, representative cohort of HIV-positive adults	Prospective cohort study Multistage probability sampling using sequential enrollment or list-based systematic random sampling of clients from a stratified sample of medical and social service agencies	Homeless: sleeping on the street, drop-in center, or shelter, SRO, place not intended for sleeping Unstably housed: transitional housing, jail, treatment facility with no other place to live, temporarily doubled up in someone else’s home Own place and stably housed: permanent housing in an apartment, house, or congregate setting	Risk behaviors Sex behavior	Recent homelessness was associated with unprotected sex with HIV-negative or status unknown partner among men sexually active with women in unadjusted but not adjusted models Recent homelessness was associated with unprotected sex among sexually active women in both unadjusted and adjusted models Women who experienced recent homelessness were significantly more likely to exchange sex for money or drugs in both unadjusted and adjusted models
Aidala et al.³⁶; New York City	To examine sexual relationships and sexual behaviors among HIV-positive men sexually active with women and racial/ethnic differences in sexual behavior and sexual risk	Prospective cohort study Multistage probability sampling using sequential enrollment or list-based systematic random sampling of clients from a stratified sample of medical and social service agencies	Homeless: sleeping on the street, drop-in center or shelter, SRO, place not intended for sleeping Unstably housed: transitional housing, jail, halfway house, treatment facility, doubled up in someone else’s home; own place and stably housed: permanent housing in an apartment, house, or congregate setting	Risk behaviors Sex behavior	In analyses over time, recent homelessness was associated with unprotected sex with an HIV-negative or status unknown woman partner among the total sample and among the subsample of African American men
Aidala et al.³¹; 18 primarily urban US service areas	To examine HIV drug and sex risk behaviors among PWH with no or inadequate housing compared with PWH with stable housing; to examine change in risk behavior associated with change in housing status	Prospective cohort–pooled data from multisite intervention study Sequential enrollment at first visit for medical or social services during study period	Homeless: sleeping on the street, place not intended for sleeping, shelter, SRO; unstably housed: in a temporary housing, jail, drug treatment with no other address, doubled up with others; improved housing status: change from homeless to unstably housed or stably housed, or from unstably housed to stably housed; worse housing status: change from stably housed to unstably housed or homeless, or from unstably housed to homeless	Risk behaviors Drug and sex behavior	Recent drug use, needle use, or sex exchange at baseline higher among homeless and unstably housed PWH than among PWH with stable housing PWH whose housing status improved between baseline and follow-up significantly reduced drug use, needle use, needle sharing, and unprotected sex; PWH whose housing status worsened were more likely to engage in sex exchange In both cross-sectional and longitudinal analyses, homeless PWH had higher rates of risk behavior than did unstably housed PWH and both had higher rates of risk behaviors than did stably housed PWH
Palepu et al.³³; Boston	To examine the association of substance abuse treatment with sexual and drug use risk behaviors among PWH with a history of alcohol problems	Prospective cohort study Convenience sample of PWH screening positive for alcohol problems; recruited from primarily medical settings serving PWH including a respite care facility	Homeless: ≥ 1 nights on the street or in a shelter in the past 6 mo	Risk behaviors Drug and sex behavior	At baseline, homeless PWH with alcohol problems had higher drug risk scores than did those with no recent homeless experience; sexual risk scores were similar In overtime models, homeless status was associated with higher drug risk scores, regardless of receipt of alcohol or drug treatment

Note. ART = antiretroviral treatment; CA-MRSA = community-associated methicillin-resistant Staphylococcus aureus; DTES = Downtown Eastside; ED = emergency department; HAART = highly active ART; IDU = injection drug user; PWH = people with HIV or AIDS; QOL = quality of life; RCT = randomized controlled trial; SES = socioeconomic status; SRO = single-room occupancy; VA = Veterans Affairs.