Low HCV-RNA prevalence and low anti HCV incidence in a large national sample of PWID in opioid substitution treatment in Germany: a prospective cohort study
Hepatitis C virus (HCV) infection is highly prevalent among patients in opioid substitution treatment (OST). National epidemiological data on the prevalence and incidence of HCV among patients receiving OST in Germany is lacking, but urgently needed to calculate the current and future burden of HCV infection in this high risk-group. The “Epidemiology of hepatitis C virus infection among people receiving opioid substitution treatment (ECHO)” study provides national and regional data on the HCV prevalence and incidence among patients in routine OST care in Germany.
ECHO is an observational, non-interventional, longitudinal study conducted between 2014 and 2017 among a large representative sample of OST patients in Germany. Baseline data was collected from routine clinical data as well as questionnaires administered to OST patients and OST physicians. For HCV status at baseline and prevalence calculations, we either used the most recent routine clinical data available or physicians performed HCV RNA and antibody testing. Patients that were anti-HCV negative at baseline were followed up after 12 months to calculate the HCV incidence in this group, as well as to identify factors associated with seroconversion. Anti-HCV and RNA prevalence rates, including 95% confidence intervals, were calculated based on data from all OST patients at baseline. The incidence of anti-HCV seroconversion was calculated using the subsample of patients who were HCV seronegative at baseline. We only included patients with recorded test dates to enable the calculation of person-time. Incidence rates per person-years were calculated by dividing the number of new cases by the total person-time (i.e. the time each person was observed, totalled for all persons).
Sixty-three OST units from 14 German Federal States provided clinical data of 2467 opioid substituted patients. Data on the hepatitis C status was available for 2245 patients. HCV-antibody and HCV-RNA prevalence was 57.8% and 27.6% respectively. Among the 625 antibody positive and RNA negative patients, 224 (35.8%) were previously treated for HCV infection. HCV-RNA prevalence rates were significantly higher among men (29.5%) than women (22.5%). Older patients and patients with an earlier onset of opioid dependence were significantly more likely to test positive for HCV-antibodies or HCV-RNA. The HCV incidence rate in our sample was 2.1 cases per 100-person years.
The low HCV-RNA prevalence and low HCV incidence rates indicate that OST is an effective setting in Germany for treating chronic HCV infections and for reducing new infections. The study underlines the need to expand the provision of OST in Germany and to increase the HCV treatment uptake rate among OST patients to reduce the HCV related morbidity and mortality in this high-risk population.