Cost-effectiveness of multi-component interventions to prevent delirium in older people admitted to medical wards

Abstract
Introduction: there is evidence to suggest that delirium incidence can be reduced in older people admitted to medical services using multi-component interventions that target delirium risk factors. The cost-effectiveness of this approach is uncertain. We therefore developed a novel cost-effectiveness model for delirium prevention. Method: we compared multi-component delirium prevention intervention with usual care using a model based on a decision tree analysis. The model was used to estimate the incremental net monetary benefit (INMB). The robustness of the cost-effectiveness result was explored using deterministic and probabilistic sensitivity analyses. Result: the multi-component prevention intervention was cost-effective when compared with usual care. It was associated with an INMB of £2,200 using a cost-effectiveness threshold of £20,000 per quality-adjusted life year (QALY). It remained cost-effective in the majority of the deterministic sensitivity analyses and was cost-effective in 96.8% of the simulations carried out in the probabilistic sensitivity analysis. Discussion: our analysis has shown convincingly that multi-component prevention interventions for delirium should be considered as a cost-effective health-care strategy for medically ill people admitted to hospital. It is an attractive intervention for health-care planners as they strive to reconfigure their services to better meet the needs of an ageing population.