OBJECTIVES

The IQVIA Core Diabetes Model (CDM) contains several risk equations to predict cardiovascular events, including a set of individual end-point Framingham (EPF) equations estimating the incidence of coronary heart disease (CHD), stroke and congestive heart failure (CHF). In 2008, the same Framingham Heart Study investigators published a generalized algorithm to calculate a composite cardiovascular disease (CVD) risk. The updated CDM 9.5 version includes this general Framingham (GF) CVD equation. The current study compared the outcomes obtained with GF against EPF equations.

METHODS

Baseline characteristics and treatment effects from the observational EDGE study comparing metformin + vildagliptin (M+V) with metformin + sulphonylurea (M+S) were employed: mean age 57.8 years, diabetes duration 6 years, 54.8% male, HbA1c 8.2% and BMI 29kg/m²; HbA1c reductions were -0.99% and -1.19%, with changes of -0.3kg and -1.6kg in body weight for M+S and M+V, respectively. Basal insulin rescue therapy was applied to both arms when HbA1c surpassed 7.5%. A dynamic risk-factor-related weighting algorithm, based on UKPDS68, matched the composite CVD risk score from GF to the individual end-points of CDM. UK 2018 costs were applied; costs and health benefits were discounted at 3.5% per year.

RESULTS

Using GF, mean life expectancy (-0.4 years) and QALY (-0.3) decreased in both arms due to higher cumulative incidence of CVD (+10%) and consequent increase in CVD-related mortality (+6%). Repartition of events also changed, as incidence of CHF was reduced (-18%), while stroke (+17%) and MI (+12%) increased. Costs increased by 6%. However, impact on incremental cost-utility ratio (ICUR) was minor, decreasing from 10,288GBP/QALY in EPF to 10,133GBP/QALY in GF.

CONCLUSIONS

The use of GF along with a risk-factor weighting algorithm resulted in higher incidence of CVD, with a different distribution of events compared to applying the EPF equations. Despite important differences in total costs and disease incidence, the ICUR was maintained.