Food is Medicine for HIV: Improved health and hospitalizations in the Changing Health through Food Support (CHEFS-HIV) pragmatic randomized trial.

BACKGROUND: Policy support for "Food is Medicine"-medically tailored meals or groceries to improve health-is rapidly growing. No randomized trials have heretofore investigated the benefits of medically tailored food programs for people living with HIV (PLHIV). METHODS: The CHEFS-HIV pragmatic randomized trial included PLHIV who were clients of Project Open Hand (POH), a San Francisco-based nonprofit food organization. The intervention arm (n = 93) received comprehensive medically tailored meals, groceries, and nutritional education. Control participants (n = 98) received less intensive (POH "standard of care") food services. Health, nutrition, and behavioral outcomes were assessed at baseline and 6 months later. Primary outcomes measured were viral non-suppression and health related quality of life. Mixed models estimated treatment effects as differences-in-differences between arms. RESULTS: The intervention arm had lower odds of hospitalization (odds ratio [OR] = 0.11), food insecurity (OR = 0.23), depressive symptoms (OR = 0.32), antiretroviral therapy adherence <90% (OR = 0.18), and unprotected sex (OR = 0.18), and less fatty food consumption (ß= -0.170 servings/day) over 6 months, compared to the control arm. There was no difference between study arms in viral non-suppression and health-related quality of life over 6 months. CONCLUSIONS: A "Food-is-Medicine" intervention reduced hospitalizations and improved mental and physical health among PLHIV, despite no impact on viral suppression. CLINICAL TRIALS REGISTRATION: NCT03191253.

Lessons for expanding virtual mentoring in academic medical institutions: a qualitative study among senior mentors.

BACKGROUND: Virtual activities, hybrid work and virtual mentoring have become part of the ongoing milieu of academic medicine. As the shift to remote mentoring continues to evolve, it is now possible to adapt, refine, and improve tools to support thriving mentoring relationships that take place virtually. This study explores strategies for virtual mentoring as a cornerstone for effective training programs among senior mentors participating in an ongoing mentoring program. METHODS: We conducted a qualitative study among prior and current participants of an ongoing "Mentoring the Mentors" program about key strategies for optimizing virtual mentoring. Data were coded and analyzed following a thematic analysis approach. RESULTS: Respondents were mostly female (62%), white (58%), and associate (39%) or full professors (32%). We found that, with the expansion of hybrid and fully remote work, there are now fewer opportunities for informal but important chance meetings between mentors and mentees; however, virtual mentoring provides opportunities to compensate for reduced interactivity normally experienced in the workplace. The heightened need to plan and be more deliberate in the virtual sphere was woven throughout narratives and was the foundation of most recommendations. Specifically, a central obstacle for respondents was that spontaneous conversations were harder to initiate because virtual conversations are expected to have set agendas. CONCLUSIONS: Developing new ways to maintain meaningful interpersonal relationships in a virtual training environment, including opportunities for serendipitous and informal engagement, is critical to the success of virtual mentoring programs.

Cocaine Use is Associated With Increased LVMI in Unstably Housed Women With Polysubstance Use.

BACKGROUND: While substance use is known to influence cardiovascular health, most prior studies only consider one substance at a time. We examined associations between the concurrent use of multiple substances and left ventricular mass index (LVMI) in unhoused and unstably housed women. METHODS: Between 2016 and 2019, we conducted a cohort study of unstably housed women in which measurements included an interview, serum/urine collection, vital sign assessment, and a single transthoracic echocardiogram at baseline. We evaluated independent associations between 39 separate substances confirmed through toxicology and echocardiography-confirmed LVMI. RESULTS: The study included 194 participants with a median age of 53.5 years and a high proportion of women of color (72.6%). Toxicology-confirmed substance use included: 69.1% nicotine, 56.2% cocaine, 28.9% methamphetamines, 28.9% alcohol, 23.2% opioid analgesics, and 9.8% opioids with catecholaminergic effects. In adjusted analysis, cocaine was independently associated with higher LVMI (Adjusted linear effect: 18%; 95% CI 9.9, 26.6). Associations with other substances did not reach levels of significance and did not significantly interact with cocaine. CONCLUSION: In a population of vulnerable women where the use of multiple substances is common, cocaine stands out as having particularly detrimental influences on cardiac structure. Blood pressure did not attenuate the association appreciably, suggesting direct effects of cocaine on LVMI. Routinely evaluating stimulant use as a chronic risk factor during risk assessment and preventive clinical care planning may reduce end organ damage, particularly in highly vulnerable women.

HIV Treatment Outcomes in POP-UP: Drop-in HIV Primary Care Model for People Experiencing Homelessness.

BACKGROUND: People with HIV experiencing homelessness have low rates of viral suppression, driven by sociostructural barriers and traditional care system limitations. Informed by the capability-opportunity-motivation-behavior (COM-B) model and patient preference research, we developed POP-UP, an integrated drop-in (nonappointment-based) HIV clinic with wrap-around services for persons with housing instability and viral nonsuppression in San Francisco. METHODS: We report HIV viral suppression (VS; <200 copies/mL), care engagement, and mortality at 12 months postenrollment. We used logistic regression to determine participant characteristics associated with VS. RESULTS: We enrolled 112 patients with viral nonsuppression and housing instability: 52% experiencing street-homelessness, 100% with a substance use disorder, and 70% with mental health diagnoses. At 12 months postenrollment, 70% had ≥1 visit each 4-month period, although 59% had a 90-day care gap; 44% had VS, 24% had viral nonsuppression, 23% missing, and 9% died (6 overdose, 2 AIDS-associated, 2 other). No baseline characteristics were associated with VS. CONCLUSIONS: The POP-UP low-barrier HIV care model successfully reached and retained some of our clinic's highest-risk patients. It was associated with VS improvement from 0% at baseline to 44% at 12 months among people with housing instability. Care gaps and high mortality from overdose remain major challenges to achieving optimal HIV treatment outcomes in this population.

A Chronic Condition Disguised as an Acute Event: the Case for Re-thinking Stimulant Overdose Death.

Recent reports indicate that stimulant-related deaths are increasing dramatically. People who die from acute stimulant toxicity have high rates of pre-existing cardiovascular disease (CVD), much of which is undiagnosed. Moreover, people who use stimulants with CVD often remain asymptomatic until presenting to an emergency department with an acute event. Prior research shows that symptoms of stimulant toxicity may occur on a regular basis, and that people who die from stimulant toxicity are older than those who die of opioid toxicity. Taken collectively, the existing evidence suggests that death from acute stimulant toxicity is often an outcome of long-term, cumulative exposure leading to cardiovascular dysfunction rather than acute intoxication. Strategies tailored to the distinct etiology of stimulant overdose are needed. We propose a three-part approach including (1) implementing stimulant use interventions that promote not only abstinence, but also use reduction, (2) treating ongoing stimulant use as a chronic cardiovascular condition, and (3) making stimulant toxicity interventions relevant to the populations most affected, which includes people outside of the traditional health-care system. In short, to reduce stimulant-related fatality, we need to transform our approach in ways that are tailored to address its natural history.

Impact of multiple substance use on circulating ST2, a biomarker of adverse cardiac remodelling, in women.

CONTEXT: Cardiovascular disease (CVD) and heart failure (HF) are major causes of mortality in low-income populations and differ by sex. Risk assessment that incorporates cardiac biomarkers is common. However, research evaluating the utility of biomarkers rarely includes controlled substances, which may influence biomarker levels and thus influence CVD risk assessment. MATERIALS AND METHODS: We identified the effects of multiple substances on soluble "suppression of tumorigenicity 2" (sST2), a biomarker of adverse cardiac remodelling, in 245 low-income women. Adjusting for CVD risk factors, we examined associations between substance use and sST2 over six monthly visits. RESULTS: Median age was 53 years and 74% of participants were ethnic minority women. An sST2 level > 35 ng/mL (suggesting cardiac remodelling) during ≥1 study visit was observed in 44% of participants. In adjusted analysis, higher sST2 levels were significantly and positively associated with the presence of cocaine (Adjusted Linear Effect [ALE]:1.10; 95% CI:1.03-1.19), alcohol (ALE:1.10; 95% CI:1.04-1.17), heroin (ALE:1.25; 95% CI:1.10-1.43), and the interaction between heroin and fentanyl use. CONCLUSION: Results suggest that the use of multiple substances influences the level of sST2, a biomarker often used to evaluate cardiovascular risk. Incorporating substance use alongside cardiac biomarkers may improve CVD risk assessment in vulnerable women.

Emergency department visits and trends related to cocaine, psychostimulants, and opioids in the United States, 2008-2018.

BACKGROUND: Drug-related emergency department (ED) visits are escalating, especially for stimulant use (i.e., cocaine and psychostimulants such as methamphetamine). We sought to characterize rates, presentation, and management of ED visits related to cocaine and psychostimulant use, compared to opioid use, in the United States (US). METHODS: We used 2008-2018 National Hospital Ambulatory Medical Care Survey data to identify a nationally representative sample of ED visits related to cocaine and psychostimulant use, with opioids as the comparator. To make visits mutually exclusive for analysis, we excluded visits related to 2 or more of the three possible drug categories. We estimated annual rate trends using unadjusted Poisson regression; described demographics, presenting concerns, and management; and determined associations between drug-type and presenting concerns (categorized as psychiatric, neurologic, cardiopulmonary, and drug toxicity/withdrawal) using logistic regression, adjusting for age, sex, race/ethnicity, and homelessness. RESULTS: Cocaine-related ED visits did not significantly increase, while psychostimulant-related ED visits increased from 2008 to 2018 (2.2 visits per 10,000 population to 12.9 visits per 10,000 population; p < 0.001). Cocaine-related ED visits had higher usage of cardiac testing, while psychostimulant-related ED visits had higher usage of chemical restraints than opioid-related ED visits. Cocaine- and psychostimulant-related ED visits had greater odds of presenting with cardiopulmonary concerns (cocaine adjusted odds ratio [aOR] 2.95, 95% CI 1.70-5.13; psychostimulant aOR 2.46, 95% CI 1.42-4.26), while psychostimulant-related visits had greater odds of presenting with psychiatric concerns (aOR 2.69, 95% CI 1.83-3.95) and lower odds of presenting with drug toxicity/withdrawal concerns (aOR 0.47, 95%CI 0.30-0.73) compared to opioid-related ED visits. CONCLUSION: Presentations for stimulant-related ED visits differ from opioid-related ED visits: compared to opioids, ED presentations related to cocaine and psychostimulants are less often identified as related to drug toxicity/withdrawal and more often require interventions to address acute cardiopulmonary and psychiatric complications.

Coronavirus Disease 2019 (COVID-19) and HIV Spotlight the United States Imperative for Permanent Affordable Housing.

Job loss and evictions tied to the Coronavirus Disease 2019 (COVID-19) pandemic are expected to increase homelessness significantly in the coming months. Reciprocally, homelessness and the many vulnerabilities that inevitably accompany it are driving COVID-19 outbreaks in US shelters and other congregate living situations. Unless we intervene to address homelessness, these co-existing and synergistic situations will make the current public health crisis even worse. Preventing homelessness and providing permanent affordable housing has reduced the ravages of the HIV epidemic. We must take the lessons learned in 40 years of fighting HIV to respond effectively to the COVID-19 crisis. Housing is an investment that will curb the spread of COVID-19 and help protect all of us from future pandemics.

Cocaine Use and White Matter Hyperintensities in Homeless and Unstably Housed Women.

OBJECTIVES: Cocaine use has been linked to stroke in several studies. However, few studies have considered the influence of cocaine use on stroke mechanisms such as small vessel disease (SVD). We conducted a study to assess associations between the toxicology-confirmed use of multiple drugs, including cocaine, and a marker of SVD, white matter hyperintensities (WMH). MATERIALS AND METHODS: We conducted a nested case-control study (n = 30) within a larger cohort study (N = 245) of homeless and unstably housed women recruited from San Francisco community venues. Participants completed six monthly study visits consisting of an interview, blood draw, vital sign assessment and baseline brain MRI. We examined associations between toxicology-confirmed use of multiple substances, including cocaine, methamphetamine, heroin, alcohol and tobacco, and WMH identified on MRI. RESULTS: Mean study participant age was 53 years, 70% of participants were ethnic minority women and 86% had a history of cocaine use. Brain MRIs indicated the presence of WMH (i.e., Fazekas score>0) in 54% (18/30) of imaged participants. The odds of WMH were significantly higher in women who were toxicology-positive for cocaine (Odd Ratio=7.58, p=0.01), but not in women who were toxicology-positive for other drugs or had several other cerebrovascular risk factors. CONCLUSIONS: Over half of homeless and unstably housed women showed evidence of WMH. Cocaine use is highly prevalent and a significant correlate of WMH in this population, while several traditional CVD risk factors are not. Including cocaine use in cerebrovascular risk calculators may improve stroke risk prediction in high-risk populations and warrants further investigation.

Violence and Emergency Department Use among Community-Recruited Women Who Experience Homelessness and Housing Instability.

Women who experience housing instability are at high risk for violence and have disproportionately high rates of emergency department (ED) use. However, little has been done to characterize the violence they experience, or to understand how it may be related to ED use. We recruited homeless and unstably housed women from San Francisco shelters, free meal programs, and single room occupancy (SRO) hotels. We used generalized estimating equations to examine associations between violence and any ED use (i.e., an ED visit for any stated reason) every 6 months for 3 years. Among 300 participants, 44% were African-American, and the mean age was 48 years. The prevalence of violence experienced in the prior 6 months included psychological violence (87%), physical violence without a weapon (48%), physical violence with a weapon (18%), and sexual violence (18%). While most participants (85%) who experienced physical violence with a weapon or sexual violence in the prior 6 months had not visited an ED, these were the only two violence types significantly associated with ED use when all violence types were included in the same model (ORphysical/weapon = 1.83, 95% CI 1.02-3.28; ORsexual = 2.15, 95% CI 1.30-3.53). Only violence perpetrated by someone who was not a primary intimate partner was significantly associated with ED use when violence was categorized by perpetrator. The need to reduce violence in this population is urgent. In the context of health care delivery, policies to facilitate trauma-informed ED care and strategies that increase access to non-ED care, such as street-based medicine, could have substantial impact on the health of women who experience homelessness and housing instability.

Addressing overdose risk among unstably housed women in San Francisco, California: an examination of potential fentanyl contamination of multiple substances.

BACKGROUND: Numerous reports have led to concerns that fentanyl is added to many street drugs as an adulterant, including to stimulants like cocaine and methamphetamine, and could increase risks for negative health outcomes. METHODS: We collected information regarding recent substance use through self-report and urine toxicology (confirmed with mass spectrometry) once a month for up to 6 monthly study visits from a probability sample of 245 women in San Francisco with a history of housing instability (2016-2019). We compared the presence of fentanyl metabolites with (1) the presence of metabolites for other substances and (2) self-reported past week substance use. RESULTS: Out of 1050 study visits, fentanyl metabolites were detected 35 times (i.e., at 3% of all study visits and among 19/245, or 8% of all women). In most but not all (91%, or 32/35) of these detected cases, heroin or opioid medication use was self-reported. Among women who reported cocaine or methamphetamine use, but did not use heroin or opioid medication, fentanyl was detected in only 1 of 349 cases (0.3%). In adjusted logistic regression, the presence of fentanyl metabolites was independently associated with (1) presence of opiate, heroin, and benzodiazepine metabolites, and (2) self-reported past week use of heroin and opioid medications. Fentanyl metabolite detection was not independently associated with cocaine or methamphetamine use. CONCLUSIONS: The presence of fentanyl metabolites in this population was almost entirely among women who also reported using heroin or opioid pills. These data do not support the hypothesis that fentanyl is being routinely added to stimulants as an adulterant on a large scale in this region.

Condomless Sex and Psychiatric Comorbidity in the Context of Constrained Survival Choices: A Longitudinal Study Among Homeless and Unstably Housed Women.

We sought to identify the prevalence and independent correlates of condomless sex within a cohort of community-recruited homeless and unstably housed cisgender adult women who were followed biannually for 3 years (N = 143 HIV+ , N = 139 HIV-). Nearly half (44%) of participants reported condomless sex in the 6 months before baseline, which increased to 65% throughout the study period. After adjusting for having a primary partner, longitudinal odds of condomless sex among women with HIV were significantly higher among those reporting < daily use of alcohol or cannabis (AOR = 2.09, p =.002, and 1.88, p =.005, respectively) and PTSD (AOR = 1.66, p =.034). Among women without HIV, adjusted longitudinal odds of condomless sex were significantly higher for those reporting < daily methamphetamine use (AOR = 2.02, p =.012), panic attack (AOR = 1.74, p =.029), and homelessness (AOR = 1.67, p = .006). Associations were slightly attenuated when adjusting for sex exchange. Targeted HIV/STI programs for unstably housed women should address anxiety and trauma disorders, infrequent substance use, and housing challenges.

Housing First: Unsuppressed Viral Load Among Women Living with HIV in San Francisco.

While poverty is an established barrier to achieving success at each step of the HIV care continuum, less is known about specific aspects of poverty and how they overlap with behavior in exceptionally low-income individuals who live in well-resourced areas. We considered unsuppressed viral load over 3 years among women living with HIV in San Francisco who used homeless shelters, low-income hotels and free meal programs. One-hundred twenty study participants were followed; 60% had > 1 unsuppressed viral load and 19% were unsuppressed at every visit. Across six-month intervals, the odds of unsuppressed viral load were 11% higher for every 10 nights spent sleeping on the street [Adjusted Odds Ratio (AOR) 1.11, 95% CI 1.02-1.20]; 16% higher for every 10 nights spent sleeping in a shelter (AOR/10 nights 1.16, 95% CI 1.06-1.27); 4% higher for every 10 nights spent sleeping in a single-room occupancy hotel (AOR/10 nights 1.04, 95% CI 1.02-1.07); and over threefold higher among women who experienced any recent incarceration (AOR 3.56, 95% CI 1.84-6.86). Violence and recent use of outpatient health care did not significantly predict viral suppression in adjusted analysis. While strategies to promote retention in care are important for vulnerable persons living with HIV, they are insufficient to ensure sustained viral suppression in low-income women experiencing homelessness and incarceration. Results presented here in combination with prior research linking incarceration to homelessness among women indicate that tailored interventions, which not only consider but prioritize affordable housing, are critical to achieving sustained viral suppression in low-income women living with HIV.

Direct-acting antiviral treatment for HIV/HCV patients in safety net settings: patient and provider preferences.

HIV/HCV coinfected patients are a priority for direct acting antiretroviral (DAA) treatment, yet barriers to treating vulnerable patients persist. This study surveyed safety net clinic patients and providers to quantify their preferences for DAA treatment and prioritize modifiable barriers. Preferences were assessed using best-worst scaling. General linear mixed models were used to determine whether attributes differed in importance and whether patients and providers valued attributes differently. 158 HIV/HCV coinfected patients and 49 providers participated. Patients and providers had strong preferences for treatment within the medical homes where patients receive HIV care. Support such as reminders and advice numbers were also important, but were more important to providers than patients. Providers identified lack of insurance coverage for DAA as the most significant barrier. Providers rated HIV primary care providers as best suited to deliver DAA to HIV+ patients. Addressing structural barriers is essential for increasing DAA treatment in safety net settings.

HCV treatment barriers among HIV/HCV co-infected patients in the US: a qualitative study to understand low uptake among marginalized populations in the DAA era.

BACKGROUND: Well-tolerated, highly effective HCV treatment, known as direct-acting antivirals (DAAs), is now recommended for all people living with HCV, providing the tools for HCV elimination. We sought to understand treatment barriers among low-income HIV/HCV coinfected patients and providers with the goal of increasing uptake. METHODS: In 2014, we conducted 26 interviews with HIV/HCV co-infected patients and providers from a San Francisco clinic serving underinsured and publically-insured persons to explore barriers impacting treatment engagement and completion. Interview transcripts were coded, and a thematic analysis was conducted to identify emerging patterns. RESULTS: Conditions of poverty-specifically, meeting basic needs for food, shelter, and safety-undermined patient perceptions of self-efficacy to successfully complete HCV treatment programs. While patient participants expressed interest in HCV treatment, the perceived burden of taking daily medications without strong social support was an added challenge. This need for support contradicted provider assumptions that, due to the shorter-course regimens, support is unnecessary in the DAA era. CONCLUSIONS: Interferon-free treatments alone are not sufficient to overcome social-structural barriers to HCV treatment and care among low-income HIV/HCV co-infected patients. Support for patients with unmet social needs may facilitate treatment initiation and completion, particularly among those in challenging socioeconomic situations.

A Randomized Controlled Trial of a Text Messaging Intervention to Promote Virologic Suppression and Retention in Care in an Urban Safety-Net Human Immunodeficiency Virus Clinic: The Connect4Care Trial.

Background: Text messaging is a promising strategy to support human immunodeficiency virus (HIV) care engagement, but little is known about its efficacy in urban safety-net HIV clinics. Methods: We conducted a randomized controlled trial of a supportive and motivational text messaging intervention, Connect4Care (C4C), among viremic patients who had a history of poor retention or were new to the clinic. Participants were randomized (stratified by new or established HIV diagnosis status) to receive either of the following for 12 months: (1) thrice-weekly intervention messages, plus texted primary care appointment reminders and a monthly text message requesting confirmation of study participation or (2) texted reminders and monthly messages alone. Viral load was assessed at 6 and 12 months. The primary outcome was virologic suppression (<200 copies/mL) at 12 months, estimated via repeated-measures log-binomial regression, adjusted for new-diagnosis status. The secondary outcome was retention in clinic care. Results: Between August 2013 and November 2015, a total of 230 participants were randomized. Virologic suppression at 12 months was similar in intervention and control participants (48.8% vs 45.8%, respectively), yielding a rate ratio of 1.07 (95% confidence interval, .82-1.39). Suppression was higher in those with newly diagnosed infection (78.3% vs 45.3%). There were no intervention effects on the secondary outcome. Exploratory analyses suggested that patients with more responses to study text messages had better outcomes, regardless of arm. Conclusions: The C4C text messaging intervention did not significantly increase virologic suppression or retention in care. Response to text messages may be a useful way for providers to gauge risk for poor HIV outcomes. Clinical Trials Registration: NCT01917994.

Recent stimulant use and leukocyte gene expression in methamphetamine users with treated HIV infection.

Stimulant use may accelerate HIV disease progression through biological and behavioral pathways. However, scant research with treated HIV-positive persons has examined stimulant-associated alterations in pathophysiologic processes relevant to HIV pathogenesis. In a sample of 55 HIV-positive, methamphetamine-using sexual minority men with a viral load less than 200 copies/mL, we conducted RNA sequencing to examine patterns of leukocyte gene expression in participants who had a urine sample that was reactive for stimulants (n = 27) as compared to those who tested non-reactive (n = 28). Results indicated differential expression of 32 genes and perturbation of 168 pathways in recent stimulant users. We observed statistically significant differential expression of single genes previously associated with HIV latency, cell cycle regulation, and immune activation in recent stimulant users (false discovery rate p < 0.10). Pathway analyses indicated enrichment for genes associated with inflammation, innate immune activation, neuroendocrine hormone regulation, and neurotransmitter synthesis. Recent stimulant users displayed concurrent elevations in plasma levels of tumor necrosis factor - alpha (TNF-α) but not interleukin 6 (IL-6). Further research is needed to examine the bio-behavioral mechanisms whereby stimulant use may contribute to HIV persistence and disease progression.

Cigarette Smoking among Women Who Are Homeless or Unstably Housed: Examining the Role of Food Insecurity.

Smoking prevalence remains high among individuals who are homeless, partly due to stressors related to homelessness. Beyond housing insecurity, homelessness involves financial stresses and unmet subsistence needs. In particular, food insecurity contributes to negative health outcomes and other health risks. This study examined associations between food insecurity severity and smoking among homeless and marginally housed women in San Francisco, California. We used data from 247 women from a longitudinal cohort study. Generalized estimating equations were used to estimate longitudinal associations between study factors and smoking based on data from five biannual assessment points between 2009 and 2012. The longitudinal adjusted odds of smoking were higher among severely food insecure individuals compared to those who were not food insecure (AOR = 1.68, 95% CI [1.02, 2.78]), while associations with other study factors, including demographics, time, HIV status, mental health, and substance use (except marijuana use), did not reach levels of significance. Similar adjusted longitudinal results were observed when food insecurity was the dependent variable and smoking an independent variable, suggesting the possibility of a bidirectional association. Considering unmet needs, such as food and hunger, may improve comprehensive smoking cessation strategies targeting individuals for whom mainstream tobacco control efforts have not been effective. Similarly, offering improved access to smoking cessation resources should be considered in efforts to address food insecurity among individuals experiencing homelessness.

HCV screening in a cohort of HIV infected and uninfected homeless and marginally housed women in San Francisco, California.

BACKGROUND: Hepatitis C virus (HCV) screening has taken on new importance as a result of updated guidelines and new curative therapies. Relatively few studies have assessed HCV infection in homeless populations, and a minority include women. We assessed prevalence and correlates of HCV exposure in a cohort of homeless and unstably housed women in San Francisco, and estimated the proportion undiagnosed. METHODS: A probability sample of 246 women were recruited at free meal programs, homeless shelters, and low-cost single room occupancy hotels in San Francisco; women with HIV were oversampled. At baseline, anti-HCV status was assessed using an enzyme immunoassay, and results compared in both HIV-positive and negative women. Exposures were assessed by self-report. Logistic regression was used to assess factors independently associated th HCV exposure. RESULTS: Among 246 women 45.9% were anti-HCV positive, of whom 61.1% were HIV coinfected; 27.4% of positives reported no prior screening. Most (72%) women were in the 'baby-boomer' birth cohort; 19% reported recent injection drug use (IDU). Factors independently associated with anti-HCV positivity were: being born in 1965 or earlier (AOR) 3.94; 95%CI: 1.88, 8.26), IDU history (AOR 4.0; 95%CI: 1.68, 9.55), and number of psychiatric diagnoses (AOR 1.16; 95%CI: 1.08, 1.25). CONCLUSIONS: Results fill an important gap in information regarding HCV among homeless women, and confirm the need for enhanced screening in this population where a high proportion are baby-boomers and have a history of drug use and psychiatric problems. Due to their age and risk profile, there is a high probability that women in this study have been infected for decades, and thus have significant liver disease. The association with mental illness and HCV suggests that in addition increased screening, augmenting mental health care and support may enhance treatment success.