Aims/hypothesis: Approximately 10% of total healthcare budgets worldwide are spent on treating diabetes and its complications, and budgets are increasing globally because of ageing populations and more expensive second-line medications. The aims of the study were to estimate the within-trial and lifetime cost-effectiveness of the weight management programme, which achieved 46% remissions of type 2 diabetes at year 1 and 36% at year 2 in the Diabetes Remission Clinical Trial (DiRECT).
Methods: Within-trial analysis assessed costs of the Counterweight-Plus intervention in DiRECT (including training, programme materials, practitioner appointments and low-energy diet), along with glucose-lowering and antihypertensive medications, and all routine healthcare contacts. Lifetime cost per quality-adjusted life-year (QALY) was estimated according to projected durations of remissions, assuming continued relapse rates as seen in year 2 of DiRECT and consequent life expectancy, quality of life and healthcare costs.
Results: Mean total 2 year healthcare costs for the intervention and control groups were £3036 and £2420, respectively: an incremental cost of £616 (95% CI -£45, £1269). Intervention costs (£1411; 95% CI £1308, £1511) were partially offset by lower other healthcare costs (£796; 95% CI £150, £1465), including reduced oral glucose-lowering medications by £231 (95% CI £148, £314). Net remission at 2 years was 32.3% (95% CI 23.5%, 40.3%), and cost per remission achieved was £1907 (lower 95% CI: intervention dominates; upper 95% CI: £4212). Over a lifetime horizon, the intervention was modelled to achieve a mean 0.06 (95% CI 0.04, 0.09) QALY gain for the DiRECT population and mean total lifetime cost savings per participant of £1337 (95% CI £674, £2081), with the intervention becoming cost-saving within 6 years.
Conclusions/interpretation: Incorporating the lifetime healthcare cost savings due to periods of remission from diabetes and its complications, the DiRECT intervention is predicted to be both more effective (QALY gain) and cost-saving in adults with type 2 diabetes compared with standard care. This conclusion appears robust to various less favourable model scenarios, providing strong evidence that resources could be shifted cost-effectively to support achieving remissions with the DiRECT intervention.
Trial registration: ISRCTN03267836 Graphical abstract.
Keywords: Caloric restriction; Cost benefit; Cost-effectiveness; Type 2 diabetes; Weight loss.