Abstract

Objective: To examine the performance of the UKPDS Risk Engine (version 3) and the Framingham risk equations (2008) in estimating cardiovascular disease (CVD) incidence in three populations: (i) individuals with known diabetes (DM); (ii) individuals with non-diabetic hyperglycaemia, HbA_1c≥6.0% (HG); (iii) individuals with HbA_1c<6.0% (normoglycaemia) (NG).

Research Design and Methods: Population-based prospective cohort (EPIC-Norfolk). Participants aged 40–79 years recruited from UK general practices attended a health examination (1993–1998) and were followed for CVD events/death until April 2007. CVD risk estimates were calculated for 10,137 individuals.

Results: Over 10.1 years there were 69 CVD events in the DM group (25.4%), 160 in the HG group (17.7%) and 732 in the NG group (8.2%). Estimated CVD 10-year risk in the DM group was 33% and 37% using the UKPDS and Framingham equations respectively. In the HG group, estimated CVD risk was 31% and 22% respectively, and for the NG group, 20% and 14% respectively. There were no significant differences in the ability of the risk equations to discriminate between individuals at different risk of CVD events in each sub-group; both equations over-estimated CVD risk. The Framingham equations performed better in HG and NG groups as they did not over-estimate risk as much as the UKPDS Risk Engine and they classified more participants correctly.

Conclusions: Both the UKPDS and Framingham risk equations were moderately effective at ranking individuals and are therefore suitable for resource prioritisation. However, both over-estimated true risk which is important when using scores to communicate prognostic information to individuals.