A retrospective audit with subsequent cost and environmental analysis of a denosumab self-injection program.

The Metabolic Bone Health Department, Cardiff and Vale University Health Board, serves a local population of approximately 445 000 people. A retrospective audit of attendance data regarding the denosumab treatment clinic (the traditional treatment pathway) and the denosumab Self-Injection Program (SIP) was conducted to determine whether the SIP is both cost-effective and environmentally beneficial, compared to the traditional treatment pathway. Cost analysis was then conducted by the Finance Department. The audit was conducted over 3 years following the implementation of the service development; 233 patients had enrolled in the program at the time of the audit and 69 had completed 3 years of self-injected treatment. A control group of 497 patients were identified by the service. This group remained on the historical pathway and had consistent attendance activity over the 3-yr period from 2017 to 2019. Pre- and post-period activity of all patients on the program was compared, together with the activity for the independent control group. The SIP resulted in a reduction in clinical contacts, with financial analysis showing a total opportunity cost saving per patient of £420 per annum. There were obvious benefits to the patient of a reduced number of visits to a clinical site, which also resulted in an estimated carbon footprint reduction of 59 kg CO