Estimation of the future burden of disease of Hepatitis C in Greece and assessment of new therapies using mathematical modelling approaches

Doctoral Dissertation uoadl:2741792 492 Read counter

Unit:
Τομέας Δημόσιας Υγείας
Library of the School of Health Sciences
Deposit date:
2018-04-18
Year:
2018
Author:
Ilias Gountas
Dissertation committee:
Βασιλική-Αναστασία Σύψα, Επίκουρη Καθηγήτρια, Επιδημιολογίας και Προληπτικής Ιατρικής, Εργαστήριο Υγιεινής, Επιδημιολογίας και Ιατρικής Στατιστικής, Ιατρική Σχολή, ΕΚΠΑ

Γεώργιος Παπαθεοδωρίδης, Καθηγητής Παθολογίας-Γαστρεντερολογίας, Ιατρική Σχολή ΕΚΠΑ

Κυριάκος Σουλιώτης, Αναπληρωτής Καθηγητής Πολιτικής Υγείας, Σχολή Κοινωνικών Επιστημών Πανεπιστημίου Πελοποννήσου

Άγγελος Χατζάκης, Καθηγητής Επιδημιολογίας και Προληπτικής Ιατρικής, Εργαστήριο Υγιεινής, Επιδημιολογίας και Ιατρικής Στατιστικής, Ιατρική Σχολή, ΕΚΠΑ

Δημήτριος Παρασκευής, Επίκουρος Καθηγητής Επιδημιολογίας και Προληπτικής Ιατρικής, Εργαστήριο Υγιεινής, Επιδημιολογίας και Ιατρικής Στατιστικής, Ιατρική Σχολή, ΕΚΠΑ

Κλέα Κατσουγίαννη, Καθηγήτρια Επιδημιολογίας και Προληπτικής Ιατρικής, Εργαστήριο Υγιεινής, Επιδημιολογίας και Ιατρικής Στατιστικής, Ιατρική Σχολή, ΕΚΠΑ

Σπήλιος Μανωλακόπουλος, Αναπληρωτής Καθηγητής Παθολογίας-Γαστρεντερολογίας, Ιατρική Σχολή ΕΚΠΑ
Original Title:
Εκτίμηση του φορτίου της Ηπατίτιδας C στην Ελλάδα και αξιολόγηση της επίδρασης των θεραπειών με χρήση μαθηματικών μοντέλων
Languages:
Greek
Translated title:
Estimation of the future burden of disease of Hepatitis C in Greece and assessment of new therapies using mathematical modelling approaches
Summary:
Hepatitis C (HCV) infection is one of the major public health problems of our time. World Health Organization (WHO) targets the elimination of the disease by 2030 (80% reduction in incidence and 65% reduction in liver related mortality in 2030 compared to 2015). To achieve this goal, each country should implement appropriate health-care strategies depending on its epidemics. The aims of the present thesis are to investigate the effectiveness of prevention and treatment strategies leading to the elimination of HCV, both in the general population and among the population of people who inject drugs. An additional objective of the thesis is to identify whether the intervention leading to elimination of HCV is cost-effective or/and cost-saving in Greece.

The specificities of the disease, such as the often-unknown onset time or/and the heterogeneous transition time between the stages of the disease, favor the analysis using multi-state Markov models. In these model, patients pass through a series of stages, using appropriate annual rates or probabilities, until the occurrence of severe disease complications or death. The study of the effectiveness of various public health strategies-policies was implemented using a multi-state Markov model calibrated to appropriate epidemiological data from Greece.

According to the model, to reduce HCV incidence and liver-related mortality in Greece in the next years, integrated treatment, preventions and diagnosis strategies should be implemented. More specifically treatment coverage should be increased up to 4.700-7.000 treatments per year (about 90.000 cumulative number of treatments by 2030). To reach this target, given the low proportion of patients who are aware of their infection (25%), diagnosis rate should increase to 4800-6800 patients per year. The expansion of harm reduction interventions, without simultaneous increases in the treatment coverage, is not expected to have a significant impact on mortality and morbidity by 2030. The model did not project any significant reductions in the burden of the disease even if the new antiviral treatments are used, without increasing the treatment coverage (7.8% reduction in liver related deaths in 2030 compared to 2015). Under an intervention leading to elimination of HCV, the number of patients with compensated cirrhosis, HCC or liver related deaths in 2030 would be lower by 77%, 72%, and 65%, respectively, compared to 2015. The cost-effectiveness analysis of the strategy showed that the proposed HCV elimination strategy was highly cost-effective (8.200 euro per averted DALY). It is important that HCV elimination strategy is an upfront investment as a significant amount of money should be spent in the beginning in order to save money later.

In Greece, the most common route of transmission of HCV is through the use of intravenous drugs. Model projections showed that elimination of Hepatitis C among intravenous drug users in Athens is possible using combined prevention strategies, which included an increase both in treatment and harm reduction coverage. Using combined interventions, the benefit is maximized as harm reduction programs reduce the incidence while antiviral treatment reduces the prevalence and indirectly the incidence. To eliminate the disease by 2030, treatment coverage rates should increase to at least than 660 PWID/year (about 7800 (95% CrI: 7500-8100) treatments by 2030), with a simultaneous annual increase of 2% in harm reduction coverage.

We also estimated the minimum number of required therapies to eliminate the disease with or without the additional expansion of harm reduction coverage in different settings concerning HCV prevalence and risk behaviors of the population. Furthermore, we examined the sustainability of HCV elimination after 2030 if treatment is discontinued. Our results emphasize that the required treatments to achieve elimination strongly rely on baseline HCV prevalence as well as the risky behaviors (sharers/non-sharers). It is more difficult to eliminate the disease in a population where a small proportion of the population has a lot of unsafe injections, compared to a setting where a higher proportion of the population has fewer unsafe injections. We have also found that in settings with baseline CHC prevalence ≤45%, antiviral treatment and harm reduction of 70% could sufficiently prevented disease rebound after 2030 regardless of the structure of the epidemic. Under a high CHC prevalence setting, harm reduction is capable of preventing disease resurgence only under medium prevalence of risk behaviors. In settings where CHC prevalence and risk behaviors are both high, counseling interventions need to be implemented in addition to previous interventions, to prevent the disease from rebounding.

In conclusion, the elimination of Hepatitis C in Greece is feasible but requires significant improvements in diagnosis, treatment coverage in the general population, as well as an increase in the coverage of harm reduction programmes in PWID population.
Main subject category:
Health Sciences
Keywords:
Hepatitis C. Greece, Projections
Index:
No
Number of index pages:
0
Contains images:
Yes
Number of references:
164
Number of pages:
143
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