OBJECTIVES: Metabolic surgery is a clinically and cost-effective treatment option for patients with comorbid type 2 diabetes (T2D) and obesity, however affordability is an important issue for the healthcare system. The aim of this analysis was to estimate the incremental budget impact associated with the introduction of a metabolic surgery programme relative to best medical care (BMC) for the treatment of comorbid T2D and obesity.

METHODS: A probabilistic open-cohort Markov model was developed to estimate the incremental cost associated with a metabolic surgery programme compared with BMC over a five-year time horizon. The analysis was conducted from the perspective of the publicly-funded healthcare system. Inputs were derived from the literature or national data sources. An annual cohort size of 200 patients was assumed with reference to existing demand for bariatric surgery among patients with T2D in Ireland. Deterministic and probabilistic sensitivity analyses were carried out to investigate uncertainty.

RESULTS: The incremental five-year budget impact was estimated at €7.39 million (95% CI: 5.41 to 9.54). Increased spending related to metabolic surgery was offset by a 24% reduction in the cost of anti-hyperglycaemic medication for patients in the metabolic surgery cohort relative to the BMC cohort. There was considerable uncertainty associated with the cost of BMC due to the potential for confidential pricing agreements and ongoing changes in pharmacological management of T2D.

CONCLUSIONS: The annual direct cost of diabetes to the Irish healthcare system has been estimated to be €580 million, of which a considerable proportion is spent on the treatment of potentially preventable complications. In this population with high healthcare utilisation, the initial investment in a metabolic surgery programme could reduce healthcare costs in the longer-term by improving patient outcomes. Precise estimation of demand for metabolic surgery is challenging owing to the influence of patient and clinician acceptability on demand.