An economic evaluation of Catalonia’s Needle Exchange Programme (NEP). Cost-Benefit analysis

Background: The Needle Exchange Programme (NEP) is a strategy aimed primarily to reduce infections such as HIV and HCV and other harms among people who inject drugs. This work presents an economic evaluation of Catalonia’s NEP through a cost-benefit analysis from the perspective of the public administration. 
Methods: In the context of a cost-benefit analysis (CBA), all results were quantified in monetary units, allowing direct comparison between costs and benefits. The costs were calculated based on the costs of acquisition, distribution, incineration, and necessary human resources. The costs of injection materials acquisition and distribution, as well as waste management were determined based on government procurement contracts. The cost of human resources was calculated based on the hourly dedication and salaries of the professionals. Infections avoided was estimated through a survey to people who inject drugs on reduction of needle sharing and the benefits were calculated based on the consequent number of antiretroviral treatments saved. All data were extrapolated to a five-year time period.
Results: The total cost of the programme was estimated at €742,221.27 per year. To calculate the benefits, three possible scenarios were considered based on two different estimations on needle sharing and their average. The most conservative scenario, the one with the least impact on reducing needle sharing, showed an annual net benefit of €1,943,835.98 in the first year or €2.28 for each syringe dispensed.
Conclusions: A good description and assessment of the costs of the Catalonia’s programme was achieved. Limitations centred on not being able to calculate benefits other than savings in antiretroviral treatment. The most conservative scenario was chosen as the central scenario, as it had the most robust sharing rate. The most optimistic scenario was considered to assume an underestimated sharing rate.  However, there is sufficient evidence to affirm that the Needle Exchange Programme generates a positive net benefit from the point of view of public health and economics, and it is expected that the real benefit could be greater if the limitations of the study are overcome.