OBJECTIVES

People with type 2 diabetes mellitus (T2DM) have an increased risk of cardiovascular disease and mortality. New classes of diabetes drugs, e.g. Sodium-Glucose Cotransporter 2 (SGLT-2) Inhibitors, have been shown to reduce the risk of heart failure, myocardial infarction, stroke and cardiovascular mortality. These cardioprotective effects are, however, not fully captured by the established risk equations from the United Kingdom Protective Diabetes Study (UKPDS) which are traditionally used in health-economic diabetes models. The study aim is to investigate the bias of ignoring these cardioprotective effects on simulated clinical and health-economic outcomes.

METHODS

The Swedish Institute of Health Economics (IHE) Diabetes Cohort model was used to evaluate an intervention with cardioprotective effects against a comparator representing current clinical practice. The model was populated with baseline characteristics based on a recent clinical trial of a SGLT-2 inhibitor along with cost and utilities from the UKPDS study. The intervention was simulated with and without cardioprotective effects.

RESULTS

The inclusion of cardioprotective effects increased the quality-adjusted life years (QALYs) by 0.295 while also increasing costs by £2,457, as a consequence of reduced incidence of complications and increased survival. The resulting incremental cost-effectiveness ratio (ICER) compared to current clinical practice decreased from £36,381 to £16,715 per QALY.

CONCLUSIONS

Health-economic modelling without explicitly accounting for cardioprotective effects substantially underestimates clinical and health-economic benefits of the new classes of diabetes drugs. The results illustrate that the inclusion of cardioprotective effects may have considerable impact on cost-effectiveness results as well as reimbursement decisions.