Hepatitis C virus care cascade in persons experiencing homelessness in the United States in the era of direct-acting antiviral agents: A scoping review

Hepatitis C Cascades: Data to Inform Hepatitis C Elimination in the United States

The United States has a goal to eliminate hepatitis C as a public health threat by 2030. To accomplish this goal, hepatitis C virus (HCV) care cascades (hereinafter, HCV cascades) can be used to measure progress toward HCV elimination and identify disparities in HCV testing and care. In this topical review of HCV cascades, we describe common definitions of cascade steps, review the application of HCV cascades in health care and public health settings, and discuss the strengths and limitations of data sources used. We use examples from the Massachusetts Department of Public Health as a case study to illustrate how multiple data sources can be leveraged to produce HCV cascades for public health purposes. HCV cascades in health care settings provide actionable data to improve health care quality and delivery of services in a single health system. In public health settings at jurisdictional and national levels, HCV cascades describe HCV diagnosis and treatment for populations, which can be challenging in the absence of a single data source containing complete, comprehensive, and timely data representing all steps of a cascade. Use of multiple data sources and strategies to improve interoperability of health care and public health data systems can advance the use of HCV cascades and speed progress toward HCV elimination.

Falling treatment uptake in the hepatitis C care cascade is a growing threat to achieving elimination

Most high-income countries are not on track to achieve the World Health Organization hepatitis C elimination targets. As elimination programmes assess growing proportions of patients in community-based pathways, rates of treatment uptake may fall. We aimed to identify factors associated with DAA treatment uptake and measure changes in their prevalence over time. We performed a time-to-treatment analysis on 2728 patients approved for hepatitis C Direct-Acting Antiviral treatment in the North Central London region between January 2016 and October 2019. We investigated the association between treatment uptake and factors including assessment/treatment setting (hospital, drug service or prison), patient age, gender, injection drug use, harmful alcohol use, cirrhosis status and previous treatment. The likelihood of treatment uptake was reduced by three independent risk factors. These included assessment setting: prison-based or drug-service pathways (aHR 0.29 or 0.81 vs. hospital outpatient pathway, 95% CI 0.21-0.40 and 0.70-0.94 respectively, p < .001); being UK-born (aHR 0.89 vs. non-UK born, 0.82-0.98, p = .01); and history of harmful alcohol use (aHR 0.84 vs. no history, 0.72-0.99, p = .04). The average number of these risk factors for not starting treatment per patient increased over time (R2  = 0.66 p < .001). Independent of these, there was an additional 5% reduction in rate of treatment initiation in each successive year of the programme (aHR 0.95, 0.91-0.99, p = .02). In conclusion, disengagement from care before treatment uptake was found to be a growing threat to elimination. Despite provision of community-based test-to-cure pathways, there are persistent barriers to treatment uptake and these are increasing over time.

Results of a Model of Delivering Hepatitis C Care in a Homeless Metropolitan Population in England

INTRODUCTION

Given the hepatitis C virus (HCV) burden and despite curative treatments, more efforts focused on scaling-up testing and treatment in homeless populations are needed. This project aimed to implement education and flexible on-site HCV testing, treatment, and follow-up for a homeless population in south London and to evaluate engagement, therapy initiation, and cure rates.

METHODS

A mobile unit (van) for on-site HCV education, screening, treatment, and follow-up was placed on the street in a well-known homeless population areas from January 2018 to September 2021. Homeless was defined as living in temporary housing (hostel/hotel-based) or living on the street (street-based). Sociodemographic status, risk factors, comorbidities, concomitant medication, and data related with HCV treatment were recorded. Univariable and multivariable modeling were performed for treatment initiation and sustained virological response (SVR).

RESULTS

Nine hundred forty homeless people were identified and 99.3% participated. 56.2% were street-based, 243 (26%) tested positive for HCV antibody, and 162 (17.4%) were viremic. Those with detectable HCV RNA had significantly more frequent psychiatric disorders, active substance use disorders, were on opioid agonist treatment, had advanced fibrosis, and had lower rates of previous treatment in comparison with undetectable HCV RNA. Overall treatment initiation was 70.4% and SVR was 72.8%. In the multivariable analysis, being screened in temporary housing (odds ratio [OR] 3.166; P = 0.002) and having opioid agonist treatment (OR 3.137; P = 0.004) were positively associated with treatment initiation. HCV treatment adherence (OR 26.552; P < 0.001) was the only factor associated with achieving SVR.

DISCUSSION

Promoting education and having flexible and reflex mobile on-site testing and treatment for HCV in the homeless population improve engagement with the health care system, meaning higher rates of treatment initiation and SVR. However, street-based homeless population not linked with harm reduction services are less likely to initiate HCV treatment, highlighting an urgent need for a broad health inclusion system.