Cost-Effectiveness of Improving Hepatitis C Diagnosis and Treatment among People Who Inject Drugs in Türkiye

Objectives: This study aimed to develop a mathematical model of hepatitis C virus (HCV) transmission and disease progression among people who inject drugs (PWID) in Türkiye and to evaluate the cost-effectiveness of improving diagnosis and treatment over a 10-year time horizon. Materials and Methods: A dynamic compartmental model was developed to estimate annual HCV prevalence and HCV-related mortality under four diagnosis-and-treatment coverage scenarios ranging from no diagnosis-and-treatment to high diagnosis-and-treatment coverage. A Bernoulli transmission model was used to estimate the force of infection and incorporated into the compartmental framework. Economic outcomes, including testing and treatment costs, and health outcomes, including infections prevented and quality-adjusted life years (QALYs), were projected for each scenario between 2020 and 2029. Incremental cost-effectiveness ratios (ICERs) were estimated for increasing diagnosis- and-treatment rates. Results: Increasing diagnosis-and-treatment rates to 25%, 50%, and 75% compared with the no diagnosis-and-treatment scenario reduced cumulative HCV cases by 61%, 91%, and 98% over 10 years, respectively. HCV-related mortality decreased by 58%, 78%, and 86%, respectively. Increasing diagnosis-and-treatment coverage from 0% to 25% resulted in ICERs of $5,092 per infection prevented and $25,653 per QALY gained. Pairwise comparison of the 25% and 50% scenarios yielded ICERs of $880 per infection prevented and $4,715 per QALY gained. However, frontier analysis identified the medium strategy as dominated, as the high diagnosis-and-treatment strategy achieved greater health gains at a lower total cost and was therefore cost-saving. Conclusion: PWID represent a key population in HCV transmission dynamics. Improving diagnosis and treatment among PWID in Türkiye could be cost-effective, and potentially cost-saving, while also contributing substantially toward achieving World Health Organization HCV elimination targets.