Modelling the impact of a national scale-up of interventions on hepatitis C virus transmission among people who inject drugs in Scotland

H. Fraser, C. Mukandavire, N.K. Martin, D. Goldberg, N. Palmateer, A. Munro, A. Taylor, M. Hickman, S. Hutchinson, P. Vickerman

Research output: Contribution to journalArticle

14 Downloads (Pure)

Abstract

Background and Aims: To reduce hepatitis C virus (HCV) transmission among people who inject drugs (PWID), Scottish Government-funded national strategies, launched in 2008, promoted scaling-up opioid substitution therapy (OST) and needle and syringe provision (NSP), with some increases in HCV treatment. We test whether observed decreases in HCV incidence post-2008 can be attributed to this intervention scale-up.
Design: A dynamic HCV transmission model amongst PWID incorporating intervention scale-up and observed decreases in behavioural risk, calibrated to Scottish HCV prevalence and incidence data for 2008/09.
Setting: Scotland, UK
Participants: PWID
Measurements: Model projections from 2008-2015 were compared with data to test whether they were consistent with observed decreases in HCV incidence amongst PWID while incorporating the observed intervention scale-up, and to determine the impact of scaling-up interventions on incidence.
Findings: Without fitting to epidemiological data post-2008/09, the model incorporating observed intervention scale-up agreed with observed decreases in HCV incidence amongst PWID between 2008-2015, suggesting HCV incidence decreased by 61.3% (95% credibility interval 45.1-75.3%) from 14.2/100pyrs (9.0-20.7) to 5.5/100pyrs (2.9-9.2). On average, each model fit lay within 84% (10.1/12) of the confidence bounds for the 12 incidence data points which the model was compared against. We estimate that scale-up of interventions (OST+NSP+HCV treatment) and decreases in high-risk behaviour from 2008-2015 resulted in a 33.9% (23.8-44.6%) decrease in incidence, with the remainder (27.4% (17.6-37.0%)) explained by historical changes in OST+NSP coverage and risk pre-2008. Projections suggest scaling-up of all interventions post-2008 averted 1,492 (657-2,646) infections over 7-years, with 1,016 (308-1,996), 404 (150-836) and 72 (27-137) due to scale-up of OST+NSP, decreases in high-risk behaviour, and HCV treatment, respectively.
Conclusions: Most of the decline in hepatitis C virus (HCV) incidence in Scotland between 2008-2015 appears to be attributable to intervention scale-up (opioid substitution therapy and needle and syringe provision) due to government strategies on HCV and drugs.
Original languageEnglish
Pages (from-to)2118-2131
Number of pages14
JournalAddiction
Volume113
Issue number11
Early online date20 May 2018
DOIs
Publication statusPublished - Nov 2018

Fingerprint

Scotland
Hepacivirus
Opiate Substitution Treatment
Pharmaceutical Preparations
Syringes
Incidence
Needles
Risk-Taking
Federal Government
Therapeutics

Keywords

  • hepatitis C
  • virus transmission
  • injecting drug users
  • Scotland

Cite this

Fraser, H. ; Mukandavire, C. ; Martin, N.K. ; Goldberg, D. ; Palmateer, N. ; Munro, A. ; Taylor, A. ; Hickman, M. ; Hutchinson, S. ; Vickerman, P. / Modelling the impact of a national scale-up of interventions on hepatitis C virus transmission among people who inject drugs in Scotland. In: Addiction. 2018 ; Vol. 113, No. 11. pp. 2118-2131.
@article{32f2faf3b20943e9914f1ecd85272cdb,
title = "Modelling the impact of a national scale-up of interventions on hepatitis C virus transmission among people who inject drugs in Scotland",
abstract = "Background and Aims: To reduce hepatitis C virus (HCV) transmission among people who inject drugs (PWID), Scottish Government-funded national strategies, launched in 2008, promoted scaling-up opioid substitution therapy (OST) and needle and syringe provision (NSP), with some increases in HCV treatment. We test whether observed decreases in HCV incidence post-2008 can be attributed to this intervention scale-up.Design: A dynamic HCV transmission model amongst PWID incorporating intervention scale-up and observed decreases in behavioural risk, calibrated to Scottish HCV prevalence and incidence data for 2008/09. Setting: Scotland, UKParticipants: PWIDMeasurements: Model projections from 2008-2015 were compared with data to test whether they were consistent with observed decreases in HCV incidence amongst PWID while incorporating the observed intervention scale-up, and to determine the impact of scaling-up interventions on incidence. Findings: Without fitting to epidemiological data post-2008/09, the model incorporating observed intervention scale-up agreed with observed decreases in HCV incidence amongst PWID between 2008-2015, suggesting HCV incidence decreased by 61.3{\%} (95{\%} credibility interval 45.1-75.3{\%}) from 14.2/100pyrs (9.0-20.7) to 5.5/100pyrs (2.9-9.2). On average, each model fit lay within 84{\%} (10.1/12) of the confidence bounds for the 12 incidence data points which the model was compared against. We estimate that scale-up of interventions (OST+NSP+HCV treatment) and decreases in high-risk behaviour from 2008-2015 resulted in a 33.9{\%} (23.8-44.6{\%}) decrease in incidence, with the remainder (27.4{\%} (17.6-37.0{\%})) explained by historical changes in OST+NSP coverage and risk pre-2008. Projections suggest scaling-up of all interventions post-2008 averted 1,492 (657-2,646) infections over 7-years, with 1,016 (308-1,996), 404 (150-836) and 72 (27-137) due to scale-up of OST+NSP, decreases in high-risk behaviour, and HCV treatment, respectively. Conclusions: Most of the decline in hepatitis C virus (HCV) incidence in Scotland between 2008-2015 appears to be attributable to intervention scale-up (opioid substitution therapy and needle and syringe provision) due to government strategies on HCV and drugs.",
keywords = "hepatitis C, virus transmission , injecting drug users, Scotland",
author = "H. Fraser and C. Mukandavire and N.K. Martin and D. Goldberg and N. Palmateer and A. Munro and A. Taylor and M. Hickman and S. Hutchinson and P. Vickerman",
note = "Acceptance in SAN AAM: 12m embargo",
year = "2018",
month = "11",
doi = "10.1111/add.14267",
language = "English",
volume = "113",
pages = "2118--2131",
journal = "Addiction",
issn = "0965-2140",
publisher = "Wiley",
number = "11",

}

Modelling the impact of a national scale-up of interventions on hepatitis C virus transmission among people who inject drugs in Scotland. / Fraser, H.; Mukandavire, C.; Martin, N.K.; Goldberg, D.; Palmateer, N.; Munro, A.; Taylor, A.; Hickman, M.; Hutchinson, S.; Vickerman, P.

In: Addiction, Vol. 113, No. 11, 11.2018, p. 2118-2131.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Modelling the impact of a national scale-up of interventions on hepatitis C virus transmission among people who inject drugs in Scotland

AU - Fraser, H.

AU - Mukandavire, C.

AU - Martin, N.K.

AU - Goldberg, D.

AU - Palmateer, N.

AU - Munro, A.

AU - Taylor, A.

AU - Hickman, M.

AU - Hutchinson, S.

AU - Vickerman, P.

N1 - Acceptance in SAN AAM: 12m embargo

PY - 2018/11

Y1 - 2018/11

N2 - Background and Aims: To reduce hepatitis C virus (HCV) transmission among people who inject drugs (PWID), Scottish Government-funded national strategies, launched in 2008, promoted scaling-up opioid substitution therapy (OST) and needle and syringe provision (NSP), with some increases in HCV treatment. We test whether observed decreases in HCV incidence post-2008 can be attributed to this intervention scale-up.Design: A dynamic HCV transmission model amongst PWID incorporating intervention scale-up and observed decreases in behavioural risk, calibrated to Scottish HCV prevalence and incidence data for 2008/09. Setting: Scotland, UKParticipants: PWIDMeasurements: Model projections from 2008-2015 were compared with data to test whether they were consistent with observed decreases in HCV incidence amongst PWID while incorporating the observed intervention scale-up, and to determine the impact of scaling-up interventions on incidence. Findings: Without fitting to epidemiological data post-2008/09, the model incorporating observed intervention scale-up agreed with observed decreases in HCV incidence amongst PWID between 2008-2015, suggesting HCV incidence decreased by 61.3% (95% credibility interval 45.1-75.3%) from 14.2/100pyrs (9.0-20.7) to 5.5/100pyrs (2.9-9.2). On average, each model fit lay within 84% (10.1/12) of the confidence bounds for the 12 incidence data points which the model was compared against. We estimate that scale-up of interventions (OST+NSP+HCV treatment) and decreases in high-risk behaviour from 2008-2015 resulted in a 33.9% (23.8-44.6%) decrease in incidence, with the remainder (27.4% (17.6-37.0%)) explained by historical changes in OST+NSP coverage and risk pre-2008. Projections suggest scaling-up of all interventions post-2008 averted 1,492 (657-2,646) infections over 7-years, with 1,016 (308-1,996), 404 (150-836) and 72 (27-137) due to scale-up of OST+NSP, decreases in high-risk behaviour, and HCV treatment, respectively. Conclusions: Most of the decline in hepatitis C virus (HCV) incidence in Scotland between 2008-2015 appears to be attributable to intervention scale-up (opioid substitution therapy and needle and syringe provision) due to government strategies on HCV and drugs.

AB - Background and Aims: To reduce hepatitis C virus (HCV) transmission among people who inject drugs (PWID), Scottish Government-funded national strategies, launched in 2008, promoted scaling-up opioid substitution therapy (OST) and needle and syringe provision (NSP), with some increases in HCV treatment. We test whether observed decreases in HCV incidence post-2008 can be attributed to this intervention scale-up.Design: A dynamic HCV transmission model amongst PWID incorporating intervention scale-up and observed decreases in behavioural risk, calibrated to Scottish HCV prevalence and incidence data for 2008/09. Setting: Scotland, UKParticipants: PWIDMeasurements: Model projections from 2008-2015 were compared with data to test whether they were consistent with observed decreases in HCV incidence amongst PWID while incorporating the observed intervention scale-up, and to determine the impact of scaling-up interventions on incidence. Findings: Without fitting to epidemiological data post-2008/09, the model incorporating observed intervention scale-up agreed with observed decreases in HCV incidence amongst PWID between 2008-2015, suggesting HCV incidence decreased by 61.3% (95% credibility interval 45.1-75.3%) from 14.2/100pyrs (9.0-20.7) to 5.5/100pyrs (2.9-9.2). On average, each model fit lay within 84% (10.1/12) of the confidence bounds for the 12 incidence data points which the model was compared against. We estimate that scale-up of interventions (OST+NSP+HCV treatment) and decreases in high-risk behaviour from 2008-2015 resulted in a 33.9% (23.8-44.6%) decrease in incidence, with the remainder (27.4% (17.6-37.0%)) explained by historical changes in OST+NSP coverage and risk pre-2008. Projections suggest scaling-up of all interventions post-2008 averted 1,492 (657-2,646) infections over 7-years, with 1,016 (308-1,996), 404 (150-836) and 72 (27-137) due to scale-up of OST+NSP, decreases in high-risk behaviour, and HCV treatment, respectively. Conclusions: Most of the decline in hepatitis C virus (HCV) incidence in Scotland between 2008-2015 appears to be attributable to intervention scale-up (opioid substitution therapy and needle and syringe provision) due to government strategies on HCV and drugs.

KW - hepatitis C

KW - virus transmission

KW - injecting drug users

KW - Scotland

U2 - 10.1111/add.14267

DO - 10.1111/add.14267

M3 - Article

VL - 113

SP - 2118

EP - 2131

JO - Addiction

JF - Addiction

SN - 0965-2140

IS - 11

ER -