Interventions for reducing hepatitis C infection in people who inject drugs

The
first global review to quantify the impact of needle syringe programmes (NSP)
and opioid substitution treatment (OST) in reducing the risk of becoming
infected with the hepatitis C virus is published in Cochrane Library Drug and Alcohol Review Group and the journal Addiction.
The study, has implications for millions of people who are ‘at risk’ from
infection.

Over
70 million people live with hepatitis C and there are three to four million
people newly infected each year. The main risk for becoming infected in
developing countries is associated with illicit drug use and sharing used
needles/syringes. In many countries, at least half the people who have
injected drugs such as heroin, cocaine or methamphetamine have hepatitis C.

While
it is known that the provision of sterile injecting equipment through NSPs or
providing OST such as methadone or buprenorphine reduces injecting risk
behaviour, and there is evidence also that OST and NSP reduces HIV
transmission. Until now, there has been insufficient evidence that OST
and NSP can also protect against HCV infection.

Researchers
from the University of Bristol, the London School of Hygiene & Tropical
Medicine, and other institutions around the world examined whether NSP and OST,
provided alone or together, are effective in reducing the chances of becoming
infected with hepatitis C in people who inject drugs.

The
team identified 28 research studies across Europe, Australia, North America and
China. On average across the studies, the rate of new hepatitis C infections
per year was 19.0 for every 100 people. Data from 11,070 people who inject
drugs who were not infected with hepatitis C at the start of the study were
combined in the analysis. Of the sample, 32 per cent were female, 50 per cent
injected opioids, 51 per cent injected daily, and 40 per cent had been
homeless.

There
was consistent and strong evidence that current use of OST (defined as use at
the time of survey or within the previous six months) reduces risk of hepatitis
C infection by 50 per cent and when combined with high coverage NSP reduces
risk by 74 per cent. However, there was more uncertainty on the
effectiveness of NSP alone. Studies in Europe which tended to measure
high coverage in terms of the people who receive 100 per cent sterile syringes
per injection showed more than 50 per cent reduction in HCV, but studies in
North America which often measured coverage in terms of frequency of NSP
attendance showed little effect. There were no randomised controlled
trials (RCT) of either OST or NSP on HCV.

Dr Lucy Platt, lead author and Associate Professor in Public Health
Epidemiology from the London School of Hygiene & Tropical Medicine, said:

“This is the first global
systematic review of quantitative studies on the effectiveness of OST and NSP
on reducing Hepatitis C. Our findings provide strong evidence that OST
especially in combination with high coverage of NSP can reduce HCV
transmission. Up to half of people who inject drugs have hepatitis C: there is
an urgent need to scale up these interventions to prevent on-going
transmission, unnecessary deaths and illness.”

Matthew Hickman, author and Professor in Public Health and
Epidemiology and Head of Population Health Sciences at the University of Bristol, added:

“Globally access to OST
and NSP is poor and in some countries (such as Russian Federation) OST is
unavailable. Our evidence underpins European and global recommendations
that OST and NSP should be expanded to prevent transmission of Hepatitis C.

“Policies
that make the cessation of injecting a requirement to qualify for OST and
prevent the distribution of needles/syringe while using OST need to be removed
to maximise reduction in HCV transmission. Scaling up OST and NSP is an
essential part of comprehensive strategies to prevent HCV transmission and
disease.

“It
is important also that the evidence base is strengthened. RCT are no longer
ethical – so better observational studies are needed with consistent measures
of NSP and OST as part of the scaling up of these interventions or PWID.”

The
study was funded by the National Institute for Health Research’s (NIHR)
Public Health Research Programme, the Health Protection Research Unit in
Evaluation of Interventions, and the European Commission Drug Prevention and
Information Programme (DIPP), Treatment as Prevention in Europe: Model
Projections.

Papers

‘Needle syringe programmes and opioid substitution therapy for preventing HCV transmission among people who inject drugs: findings from a Cochrane Review andmeta-analysis’ by Lucy Platt et al in Addiction
[open access]

‘Interventions for reducing hepatitis C infection in people who inject drugs’ by Lucy
Platt et al in Cochrane