Upload
damien-shell
View
217
Download
3
Tags:
Embed Size (px)
Citation preview
Department ofSOCIAL MEDICINE
University ofBRISTOL
HEPATITIS C AND LIVER DISEASE PREVENTION
Dr. Natasha Martin, DPhil
Matthew Hickman, Daniela De Angelis, Peter Vickerman, Katy Turner, Vivian Hope, Norah Palmateer,
Michael Sweeting, Sharon Hutchinson, Noel Craine, Graham Foster, David Goldberg, Alec Miners
Department ofSOCIAL MEDICINE
University ofBRISTOL
PUBLIC HEALTH IMPORTANCE
In UK Liver disease is 5th commonest cause of death HCV/HBV 2nd most important cause liver
disease
Worldwide HCV infection causes ~1/4 liver disease (over
350,000 deaths per year)
Department ofSOCIAL MEDICINE
University ofBRISTOL
ESTIMATED NUMBER OF PEOPLE INFECTED WITH ANTI-HCV ANTIBODIES
Sweeting et al. Biostatistics 2008; De Angelis et al, Statistics in Meical Research 2009; Ross et al EJPH in press
Department ofSOCIAL MEDICINE
University ofBRISTOL
INTERVENTION EFFECTIVENESS
NSP is effective in reducing self-reported injecting risk behaviour
BUT on HCV transmission Insufficient review level evidence that NSP is effective Weak evidence that OST is effective No review level evidence for other interventions
Palmateer et al Addiction 2010 105: 844-59 (http://www.hepcscotland.co.uk/action-plan.html
Department ofSOCIAL MEDICINE
University ofBRISTOL
POOLING UK EVIDENCE ON INTERVENTION IMPACT
Judd et al. BMJ 2005. Craine et al. J Epi & Inf 2009; Hope JVH 2010; Turner Addiction in press
Site Year Design N HCV+ve Incidence Sero-conversions
Bristol 2006 RDS 299 59% 40 per 100py 14
Leeds 2008 RDS 302 60% 7.6 per 100py 2
Birmingham 2009 RDS 310 42% 5.2 per 100py 2
Glasgow 2008-09 C'sectional NSP 947 70% 10.0 per
100py 6
Wales 2004-06 Follow-up 406/700 26% 5.6 per 100 py 17
London 2001-02 Follow-up 282/428 43% 42 per 100py 49
Department ofSOCIAL MEDICINE
University ofBRISTOL
INTERVENTION EFFECT
Intervention coverage New HCV infection
Unadjusted OR 95% CI Adjusted
OR 95% CI
(a) OST On OST* 2.6% 0.36 0.19 – 0.70 0.41 0.21 – 0.82Not on OST 6.9%(b) NSP ** ≥ 100% coverage 3.8% 0.52 0.28 -0.99 0.48 0.25 – 0.93<100% coverage 7.0% (c) COMBINEDFull HR: OST and no injecting or ≥100% NSP 2.0% 0.19 0.08 – 0.47 0.21 0.08 – 0.52
≥100% NSP, No OST 5.3% 0.52 0.23 – 1.15 0.5 0.22 – 1.12<100% NSP, On OST 4.3% 0.41 0.15 – 1.12 0.48 0.17 – 1.33Minimal HR 9.8%
Adjusted for the following covariates: female gender (AOR 2.1); homeless in last year (2,9); injected crack in last month (1.9); duration injecting <2.5 years (1.0)
* Includes or ** Excludes 86 cases (involving 0 new HCV infections) who were on OST but reported no injections in the last month (cross-sectional studies) or last year (cohort studies).
Department ofSOCIAL MEDICINE
University ofBRISTOL
BUT WHAT ABOUT THE EFFECT ON HCV PREVALENCE?
HCV prevalence has decreased over time in some settings
But none have decreased HCV to low levels
Recent data from England/Wales suggests might be increasing
ENGLAND AND WALES DATA
Sweeting, M., et al., AJE 2009. 170: 352-60
Department ofSOCIAL MEDICINE
University ofBRISTOL
BRISTOL SURVEYS – 2006 : 2009
HCV Prevalence ~53% 2006 (n=299) ~57% 2009 (n=336)
Recent infections/incidence ~40% 2006 (15 Antibody-ve PCR+ve) <10% 2009 (3 Antibody-ve PCR+ve)
> 80% reduction in incidence
Department ofSOCIAL MEDICINE
University ofBRISTOL
CAN SCALING UP THE COVERAGE OF EXISTING INTERVENTIONS REDUCE HCV PREVALENCE?
Department ofSOCIAL MEDICINE
University ofBRISTOL
IMPACT OF CHANGING COVERAGE OF OST AND NSP FROM 50%: 0%, 60%, 70%, 80%
0%
10%
20%
30%
40%
50%
60%
70%
80%
Without 60% 70% 80% 60% 70% 80% 60% 70% 80%
NSP/OST 5 years 10 years 20 years
HC
V p
revale
nce
(baseli
ne w
as 4
0%
pre
vale
nce)
Effect of scaling up both OST and NSP to 60%, 70% and 80% coverage for different durations (baseline was 50% coverage)
Department ofSOCIAL MEDICINE
University ofBRISTOL
IMPLICATIONS
NSP and OST can reduce HCV incidence. And have averted infections BUT unclear whether further scaling up
feasible or could lead to substantial reductions in HCV prevalence
Other prevention options needed Could HCV treatment have an impact?
Department ofSOCIAL MEDICINE
University ofBRISTOL
HCV ANTIVIRAL TREATMENT: BARRIERS AMONG ACTIVE IDUS
Antiviral treatment effective (~60%) for curing HCV infection and approved for active injecting drug users (IDUs)
BUT few currently being treated (<1%) Perceived reluctance/concern over high rates of:
Non-completion/compliance Re-infection following treatment
Department ofSOCIAL MEDICINE
University ofBRISTOL
MATHEMATICAL MODEL
Non-responder infected IDUs
HCV chronically
infected IDUs
Uninfectedactive IDUs
Antiviral treatment
Allow for reinfection
Infection
Death or cessation from each state
New injectors
Outcome: Impact on
HCV prevalence
Martin et al. J Hepatology 2011; J Theoretical Biology 2011
Department ofSOCIAL MEDICINE
University ofBRISTOL
PROJECTIONS
Department ofSOCIAL MEDICINE
University ofBRISTOL
RELATIVE PREVALENCE REDUCTIONS AT 10 YEARS WITH VARYING TREATMENT RATES
‘Baseline’: untreated endemic chronic infection prevalence
Martin et al. J Hepatology 2011
Department ofSOCIAL MEDICINE
University ofBRISTOL
PREVALENCE REDUCTIONS AT 10 YEARS
Population of 3500 IDUs, 1400 chronic infections• 70 treated annually (20 per 1000 IDUs)
• 30% reduction by 2021 (40% 28%)• 140 treated annually (40 per 1000 IDUs)
• 58% reduction by 2021 (40% 17%)
Martin et al. J Hepatology 2011
Department ofSOCIAL MEDICINE
University ofBRISTOL
PROJECTIONS THROUGH TIME (5, 10, 20 YEARS) ANNUALLY TREATING 20 PER 1000 IDUS
Swift and substantial reductions at low prevalence Significant reductions even at high prevalence 3500 IDUs, 1400 infected (40% prevalence), 70 treated/yr
15% reduction in 5 years (4034%) 30% reduction in 10 years (4028%) Halved in 20 years (40 20%)
Martin et al. J Hepatology 2011
Department ofSOCIAL MEDICINE
University ofBRISTOL
INCREMENTAL COST PER QALY VS. NO TREATMENT: EQUAL EFFICACY (SVR) FOR EX- AND ACTIVE IDU
Treating IDUs may be highly cost effective – and more cost effective (at prevalences <60%) than treating ex/nonIDU Averts infections
Martin et al in preparation
Department ofSOCIAL MEDICINE
University ofBRISTOL
IMPLICATIONS
Department ofSOCIAL MEDICINE
University ofBRISTOL
SCALE-UP – FROM MODELLING TO REALITY – EMPIRICAL DATA NEEDED
Trouble with models Theoretical: projections not observations Need to introduce heterogeneity:
injecting risk/ HCV treatment uptake/ SVR Model combined effects of HCV Rx, OST & NSP
BUT models can raise hypotheses/ provide theoretical framework/ justification for future work
Now empirical evidence required
Department ofSOCIAL MEDICINE
University ofBRISTOL
SCALING UP HCV TREATMENT
What are the best models/ways of delivering HCV treatment to injectors in community? Start with OST population Peer projects/ support Treatment advocacy
Who is not worth starting treatment with i.e. compliance/SVR too low