Chronic hepatitis C in Swedish subjects receiving opiate substitution therapy—Factors associated with advanced fibrosis

Abstract

Background: Opiate substitution therapy (OST) reduces the risk of death from directly drug-related causes in heroin users, allowing other chronic health problems to emerge. People who inject drugs (PWID) are exposed to hepatitis C virus (HCV), with an associated risk of chronic liver disease. We investigated HCV prevalence and liver-related morbidity in a cohort of OST recipients, and analyzed factors associated with significant hepatic fibrosis. Methods: All patients registered on 1 April 2008 in 4 clinics providing OST in the 3 largest cities in Sweden were eligible for inclusion. HCV viremic subjects were evaluated for fibrosis stage by liver biopsy, transient elastometry (TE), and/or a biochemical fibrosis index (Göteborg University Cirrhosis Index; GUCI). Factors associated with severity of fibrosis were determined by logistic regression analysis. Results: Out of 524 eligible patients, 277 consented to enrolment. Two hundred and thirty-six subjects (88%) were anti-HCV-positive, and 162 of these were viremic (69%). Significant liver fibrosis (defined as Ishak stages F3–F6, TE value ≥ 8.85 kPa, or GUCI > 0.33) was found in 69 out of 103 (67%) tested viremic patients, and was associated with alcohol intake (p = 0.03), higher body mass index (BMI; p = 0.04), and the presence of anti-HBc antibodies (indicating exposure to hepatitis B virus (HBV); p = 0.02). Conclusions: Significant liver fibrosis was detected in two-thirds of HCV viremic OST recipients in this cohort, and was associated with alcohol use, high BMI, and exposure to HBV. These findings indicate that the management of HCV and associated risk factors should be emphasized in Swedish OST programs.

Keywords::

• Opiate substitution therapy
• hepatitis C
• liver fibrosis
• risk factors

Acknowledgements

The authors would like to thank the following persons for their valuable contribution to the realization of this study: Ulla Åkerholm, Aida Pileram, Anna Vallgårda, Annkie Fridström, Katarina Rosén, Joachim von Wachenfeldt, Angelina Enqvist, Irina Komarova, Martin Kåberg, Olof Wisén (deceased), and Liz Jergle Almquist. We would also like to thank Anders Håkansson for constructive comments during the preparation of this manuscript and Jonas Björk for advice on the statistical analysis.

Declaration of interest: This study has received financial support from Schering-Plough/MSD and the Skåne Regional Council. None of the authors have any conflict of interest related to this work.