Prevalence and microelimination of Hepatitic C in intravenous drug users - improving linkage to care

Background: Around 80% of hepatitis C virus (HCV) infections in Europe are attributable to injecting drug use. Due to transmission via blood contact, people who inject drugs (PWID) have a 50 to 200 times higher risk of HCV infection compared to the general population. Since the introduction of direct antiviral agents (DAA) as interferon-free treatment options in 2014, low side-effect and efficient therapy options are available. Despite these excellent treatment prospects, some drug users are still unaware of their HCV status or are not treated despite a known HCV infection. This study aims to determine the prevalence of viral hepatitis C in a cohort of former or current intravenous drug users during inpatient treatment in the metropolitan region of Munich, to assess the knowledge of this high risk-population on HCV transmission and treatment and to improve linkage-to-care from in-hospital treatment to resident physicians.
Methods: We performed a prospective, non-interventional cross-sectional register study of inpatients in our toxicology ward between January 2022 and September 2023. Patients were eligible for inclusion if they reported a current or former intravenous drug use. Exclusion criteria were pregnancy or age <18 years. The HCV status was determined using HCV-RNA PCR and patients were asked to fill out a standardized questionnaire. In case of a positive PCR result patients were offered social counselling and a direct transferral to an infectious disease specialist and we performed a 6 and 12 month follow up interview to assess the therapy status. Statistical testing was performed on nominal variables using the Chi-square test (or Fisher exact test if the expected frequency of a cell was less than 5) and for ordinal variables using the Mann-Whitney U test.
Results: Between January 2022 and September 2023, 97 patients were included, of which 75 were included in the final analysis. The prevalence of HCV infection was 21.3%. Patients from the HCV-positive group stated significantly more frequently that they were aware of their current hepatitis C status than patients from the HCV-negative group (87.5% vs. 54.4%; p<0.001). Most patients correctly assessed their current hepatitis C status. The most important reasons given for not initiating treatment despite a known HCV Infection were lack of time and continued drug use. Regarding demographic data, substance use, substitution therapy, time spent in prison and unprotected sexual intercourse there was no significant difference between the HCV-negative and HCV-positive group. The follow-up interviews are ongoing and will be finished in September 2024.
Conclusion: Compared to the general population, the prevalence of HCV infections in our sample of i.v. drug users is significantly increased. Most of the infected persons are aware of their positive status, however no antiviral therapy has been administered, according to the patient mostly due to lack of time or continued drug use.