Long-Term Cost-Effectiveness Modelling of Invasive Urodynamic Investigations in the Management of Women With Refractory Overactive Bladder Symptoms

OBJECTIVES: Overactive bladder (OAB) is a chronic condition that has significant impacts on health, wellbeing and societal costs. FUTURE, a pragmatic multicentre superiority randomised controlled trial, compared the effectiveness of urodynamics investigation (UDS) plus comprehensive clinical assessment (CCA) against CCA alone in the management of women with refractory OAB symptoms. Our aim was to use the results from FUTURE trial to estimate the long-term cost-effectiveness of UDS.

METHODS: A de novo model was developed using a hybrid model structure with a decision tree replicating short-term within trial results and Markov processes for long-term events. By maximising the use of trial data and adopting a simple model structure, only a small number of transition probabilities needed to be sourced externally. Analysis was conducted using a UK NHS perspective and probabilistic sensitivity analyses (PSA) were conducted to capture the uncertainty in the cost-effectiveness.

RESULTS: Our analysis shows that the UDS plus CCA is more costly and associated with fewer QALYs than CCA alone, resulting in UDS plus CCA being dominated, with only a 23.4% chance of being cost-effective. However, for a prespecified subgroup of those with urgency predominant mixed urinary incontinence (MUI), the incremental cost-effectiveness ratio for UDS is £26,462, with a probability of being cost-effective of 45.3%. of £20,000 per QALY gained, rising to 53.8% at £30,000 per QALY gained.

CONCLUSIONS: The long-term cost-effectiveness of urodynamics appears to be dependent on the patient group receiving the intervention, and there is substantial uncertainty due to lack of long-term data. An extended follow-up is underway and once the results of the follow-up are available, we recommend that an analysis should be undertaken by updating the parameters within our cost-effectiveness model and undertaking a value of information analysis.