OBJECTIVES: Diabetes management guidelines recommend escalating treatment when a certain HbA1c threshold is reached. Thus, predicting in an accurate way the natural progression of HbAc1 and as such treatment duration is of key importance in diabetes models (shorter or longer use of expensive therapies). Recently, the UK Prospective Diabetes Study (UKPDS) investigators published progression equations for several risk factors including HbA1c (UKPDS90). The aim of this study was to assess the duration to treatment escalation applying the different HbA1c progression equations included in the IQVIA Core Diabetes Model v9.5Plus (CDM9.5Plus).

METHODS: In CDM9.5 two HbA1c progression equations were available in type 2 diabetes: the UKPDS68 equation and the Swedish National Diabetes Registry (SweNDR) equation. In CDM9.5Plus the UKPDS90 equations was added. A hypothetical diabetes population with an HbA1c of 8% was chosen. First year HbA1c decrease was assumed to be 1.5%. Then, the time to reach an HbA1c threshold of 7.5% was measured. This value was chosen as it is the threshold for treatment escalation used in many countries.

RESULTS: The time to reach the threshold of 7.5% was 4, 10 and 3 years for UKPDS68, SweNDR and UKPDS90 respectively. UKPDS68 and 90 are based on the same study population, only the time of follow up in UKPD90 was longer. The simulated time to escalation is comparable. However, the larger annual increase in HbA1c with UKPDS 90 is unexpected. Novel treatments classes like DPP4-inhibitors SGLT2-inhibitors and GLP-1 receptor agonists were not used in the UKPDS study, however used to a certain extent during the period the SweNDR progression equation was developed. Also, patients with diabetes are very well controlled in Sweden.

CONCLUSIONS: Annual HbA1c increase is highest with UKPDS90. This can influence outcomes in cost-effectiveness analyses. There is a need for progression equations that include newer treatment strategies.