Long term public health benefits and cost-effectiveness of two experimental drug consumption rooms in France
People who inject drugs (PWID) experienced many health problems, including chronic viral infections (HIV and HCV), skin abscesses and drug overdoses. These events are associated with complications generating a heavy burden both in terms of public health and medical costs. In France, two drug consumption rooms (DCRs) were opened in Paris and Strasbourg in 2016. Using a model-based approach, we assessed their long-term health benefits and cost-effectiveness with the COSINUS-ECO survey.
We developed an individual-based model to simulate over lifetime two cohorts of PWID: i) exposed to the DCRs over the period 2016-2026 versus ii) not exposed (n=2,997 in Paris and 2,971 in Strasbourg). The model included the following events with their medical costs: HIV and HCV infections, skin abscesses and related infective endocarditis, drug overdoses and emergency rooms visits. For each cohort, we estimated i) the number of events and associated costs over 2016-2026, ii) the lifetime number of quality-adjusted life-years (QALYs) and costs, including implementation and running costs of DCRs. DCRs effectiveness at reducing the event risks and costs were assessed using COSINUS cohort data and financial reports, respectively. Other model parameters were obtained from the literature.
In the cohorts exposed to the DCRs, for the projected period 2016-2026, we found a substantial decrease in the number of skin abscesses and associated infective endocarditis (-77%), drug overdoses (-69%) and emergency rooms visits (-65%), but modest impact on HIV and HCV infections (-11% and -6%, respectively). This resulted in 5.7/5.0 million euros of medical costs saved in Paris/Strasbourg. Accounting for implementation and running costs of DCRs, the incremental cost-effectiveness ratios were 27,200 euros/QALY in Paris and 8,200 euros/QALY in Strasbourg.
Our findings show that DCRs are highly effective to prevent harms among PWID in France and even cost-effective. They support the extension of the intervention to other French cities.