There is a stark paucity of data published concerning reinfection rates post successful treatment for HCV in currently injecting drug users. The investigators research will focus in this important area and provide desperately needed evidence to increase confidence in treating this population who carry the burden of the disease. Treating larger numbers of individuals in this population will reduce the incidence of HCV in injecting drug users and therefore reduce the overall prevalence of the disease. This will reduce the current threat to public health that HCV produces.
DETAILS OF MD RESEARCH PROJECT
STUDY HYPOTHESIS:
HCV therapy in the currently injecting group is beneficial with reinfection rates and long term outcomes comparable to those who are not current injectors.
AIMS:
1. The main aim is to determine if patients who have been successfully treated for HCV and who are currently injecting drug users have comparable rates of reinfection to those who injected drugs in the past (at least 6 months ago).
2. A secondary aim is to determine if currently injecting drug users have comparable long term outcomes to those who injected drugs in the past (at least 6 months prior to treatment) in terms of liver fibrosis and progression.
OBJECTIVES:
1. To determine the rates of reinfection in an historical cohort of drug users with HCV who have been previously treated and achieved SVR compared to those who have injected drugs in the past (at least 6 months prior to treatment) and achieved SVR with treatment.
2. To determine long term outcomes in those who injected drugs at the time of treatment and compare this to past injecting drug users (those who injected drugs at least 6 months prior to treatment).
RESEARCH QUESTIONS:
1. Do current drug users have higher rates of reinfection than past drug users?
2. Is the rate of reinfection in drug users as a whole low?
3. Does progression of fibrosis continue following successful treatment for HCV?
4. How often do currently injecting drug users stop injecting during or after treatment for HCV?
5. How often do past drug users return to injecting drug use during or following treatment?
6. Does any rise in liver enzymes persist following successful treatment?
7. What are the most commonly used drugs for injection?
8. How often do currently injecting drug users share needles/equipment?
9. Do injecting drug users know that they can be reinfected following SVR?
10. What proportion of injecting drug users drink more than the recommended weekly allowance for alcohol?
11. What is the quality of life post SVR?
METHODOLOGY
STUDY DESIGN:
This is a prospective study looking at reinfection rates based on a historical cohort of intravenous drug users that have been previously treated and achieved an SVR.
PARTICIPANTS:
There is a HCV database set up at North Manchester Hospital of all patients started on treatment since 2004. The investigator will access this and create a separate database of those patients with injecting drug use at any time as their risk factor for acquisition of HCV. The investigator will then identify those who were injecting drugs in the 6 months prior to treatment including those who continued to inject during treatment. These will be the 'active' drug using group. The investigator will then identify the group of patients that stopped injecting drugs at least 6 months prior to commencing treatment. These will be the 'past' drug using group.
CONSENT:
The investigator will be responsible for obtaining informed consent from the participants. Two copies of the consent form will be obtained - one for the participants records and one for the study file. Prior to obtaining informed consent The investigator will highlight that if any information comes to light during the course of the study pertaining to a potential criminal activity The investigator will obliged to pass this information on to the relevant authorities.
DATA COLLECTION:
All potential participants will be sent written information detailing the study and inviting them to take part. This is to avoid any possible selection bias. The investigators aim to follow up this group for 2 years to collect data on outcomes including reinfection rates using annual HCV RNA (with subsequent genotyping if positive) and liver disease progression using standard liver function blood tests and a fibroscan (a non-invasive method to assess liver fibrosis and cirrhosis).
A questionnaire regarding drug use post treatment will be done detailing any high risk practises. They will also be questioned again about drug use on treatment in order to confirm which group they should be assigned to and to reduce the possibility of previous underreporting for fears of exclusion from the treatment programme initially. Alcohol history will also be assessed. Quality of life questionnaires validated for use in HCV will be used during follow up.
The investigator is aiming to recruit 45 participants in to each group. The participants will be asked to attend for 2 visits in total one year apart. One major limitation of this study is the frequency of sampling for HCV RNA. By doing this annually the investigators may miss those reinfections that the patient clears spontaneously. However, the investigator feels that it is those with persistent viraemia and therefore persistent reinfection that are important to quantify. This is because much of the physicians' reluctance to treat active drug users comes from the perception that reinfection will occur resulting in the need for further repeated courses of treatment. Whilst those transient reinfections that the investigators may miss are very important in terms of onwards transmission, they largely do not result in the need for further treatment.
DATA HANDLING:
All new data gathered will be included in a specially designed database which will be password protected and on a limited access drive on the NHS computer, following the principles set out in the data protection act. Identifiers will be kept to an absolute minimum. Data will be stored for 25 years before being destroyed.
COMMUNICATION OF RESULTS:
The investigator is aiming to distribute and communicate the results of this study at national and international conferences. The investigator is also aiming to publish a paper in a peer reviewed journal. The participants will be informed prior to consenting that they are entitled to access to the overall results.
