Theme: Clinical Research Year: 2018
Injecting behaviour in people who inject drugs (PWID) is the main risk factor for hepatitis C
virus (HCV) infection. Psychosocial factors such as having a partner who injects drugs and
living with other drug users have been associated with increases in injecting risk behaviour.
This study aimed to investigate injecting behaviour changes during treatment for HCV
infection whilst exploring the role of psychosocial factors on patients’ injecting behaviour.
Eradicate-C was a single centred clinical trial (ISRCTN27564683) investigating the
effectiveness of HCV treatment among PWID between 2012 and 2016. A total of 94
participants completed up to 24 weeks of treatment, with social and behavioural measures
taken at different intervals throughout treatment. Data for 84 participants was analysed
retrospectively to explore mechanisms of potential behavioural changes which had occurred
Injecting frequency reduced significantly between baseline (week 1) and every 4-weekly
intervals until week 26. Not being on Opiate Substitution Therapy (OST) was associated with
a statistically significant decrease in injecting frequency, χ
(1)= 10.412, p= .001, as was
having a partner who also used drugs, in particular when that partner was also on treatment
for HCV infection, Z= -2.312, p=.021.
Treating a ‘chaotic’ population for HCV infection is not only possible, but also bears health
benefits beyond treatment of HCV alone. PWID not on OST benefited from HCV treatment
by also reducing their weekly injecting frequency. This suggests possible benefits of
therapeutic alliance for those not engaging with other health services. In addition, enrolling
couples on HCV treatment when partners are sero-concordant, has also shown enhanced
benefits for patients’ health, by reducing injecting behaviour frequency. A transformation of
individual motivation to relationship-focused motivation allows communal coping to impact
behaviour through outcome and couple efficacy. These findings have direct implications for
Disclosure of Interest Statement
AM, FS ad PD declare no conflict of interest. JFD has received honoraria for lectures and
research grants from Janssen-Cilag, Roche, Merck Sharp & Dohme, AbbVie, Bristol-Myers
Squibb and Gilead Sciences. The Eradicate-C trial was funded by Janssen-Cilag and the
Scottish Government; drug treatment was provided by Roche and Janssen-Cilag.